public-mirrors/linux
1
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-08-05 16:54:27 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions
linux/arch/s390/include/asm/lowcore.h

256 lines
7.2 KiB
C
Raw Permalink Normal View History

License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 15:07:57 +01:00
/* SPDX-License-Identifier: GPL-2.0 */
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
/*
s390/comments: unify copyright messages and remove file names Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00
* Copyright IBM Corp. 1999, 2012
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
* Author(s): Hartmut Penner <hp@de.ibm.com>,
* Martin Schwidefsky <schwidefsky@de.ibm.com>,
* Denis Joseph Barrow,
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
*/
#ifndef _ASM_S390_LOWCORE_H
#define _ASM_S390_LOWCORE_H
#include <linux/types.h>
s390/lowcore: Convert relocated lowcore alternative to machine feature Convert the explicit relocated lowcore alternative type to a more generic machine feature. This only reduces the number of alternative types, but has no impact on code generation. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-07 15:48:57 +01:00
#include <asm/machine.h>
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
#include <asm/ptrace.h>
s390/ctlreg: add struct ctlreg Add struct ctlreg to enforce strict type checking / usage for control register functions. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-09-11 21:40:04 +02:00
#include <asm/ctlreg.h>
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
#include <asm/cpu.h>
s390/kdump: add support for vector extension With this patch for kdump the s390 vector registers are stored into the prepared save areas in the old kernel and into the REGSET_VX_LOW and REGSET_VX_HIGH ELF notes for /proc/vmcore in the new kernel. The NT_S390_VXRS_LOW note contains the lower halves of the first 16 vector registers 0-15. The higher halves are stored in the floating point register ELF note. The NT_S390_VXRS_HIGH contains the full vector registers 16-31. The kernel provides a save area for storing vector register in case of machine checks. A pointer to this save are is stored in the CPU lowcore at offset 0x11b0. This save area is also used to save the registers for kdump. In case of a dumped crashed kdump those areas are used to extract the registers of the production system. The vector registers for remote CPUs are stored using the "store additional status at address" SIGP. For the dump CPU the vector registers are stored with the VSTM instruction. With this patch also zfcpdump stores the vector registers. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-06 17:57:43 +02:00
#include <asm/types.h>
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
#include <asm/alternative.h>
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
#define LC_ORDER 1
#define LC_PAGES 2
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
#define LOWCORE_ALT_ADDRESS _AC(0x70000, UL)
s390: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembler code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This is bad since macros starting with two underscores are names that are reserved by the C language. It can also be very confusing for the developers when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's now standardize on the __ASSEMBLER__ macro that is provided by the compilers. This is a completely mechanical patch (done with a simple "sed -i" statement), with some manual fixups done later while rebasing the patch. Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20250611140046.137739-3-thuth@redhat.com Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-11 16:00:46 +02:00
#ifndef __ASSEMBLER__
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
s390/traps: add struct to access transactional diagnostic block gcc-11 warns: arch/s390/kernel/traps.c: In function __do_pgm_check: arch/s390/kernel/traps.c:319:17: warning: memcpy reading 256 bytes from a region of size 0 [-Wstringop-overread] 319 | memcpy(&current->thread.trap_tdb, &S390_lowcore.pgm_tdb, 256); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by adding a struct pgm_tdb to struct lowcore and copy that. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-05 22:01:16 +02:00
struct pgm_tdb {
u64 data[32];
};
s390: rename struct _lowcore to struct lowcore Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-31 10:29:00 +01:00
struct lowcore {
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
__u8 pad_0x0000[0x0014-0x0000]; /* 0x0000 */
__u32 ipl_parmblock_ptr; /* 0x0014 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u8 pad_0x0018[0x0080-0x0018]; /* 0x0018 */
__u32 ext_params; /* 0x0080 */
s390/irq: add union/struct to access external interrupt parameters gcc-11 warns: arch/s390/kernel/irq.c: In function do_ext_irq: arch/s390/kernel/irq.c:175:9: warning: memcpy reading 4 bytes from a region of size 0 [-Wstringop-overread] 175 | memcpy(&regs->int_code, &S390_lowcore.ext_cpu_addr, 4); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by adding a struct for int_code to struct lowcore. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-05 22:01:11 +02:00
union {
struct {
__u16 ext_cpu_addr; /* 0x0084 */
__u16 ext_int_code; /* 0x0086 */
s390/lowcore: remove superfluous __packed annotations Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-01 10:59:09 +02:00
};
s390/irq: add union/struct to access external interrupt parameters gcc-11 warns: arch/s390/kernel/irq.c: In function do_ext_irq: arch/s390/kernel/irq.c:175:9: warning: memcpy reading 4 bytes from a region of size 0 [-Wstringop-overread] 175 | memcpy(&regs->int_code, &S390_lowcore.ext_cpu_addr, 4); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by adding a struct for int_code to struct lowcore. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-05 22:01:11 +02:00
__u32 ext_int_code_addr;
s390/lowcore: remove superfluous __packed annotations Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-01 10:59:09 +02:00
};
s390/entry: use assignment to read intcode / asm to copy gprs arch/s390/kernel/syscall.c: In function __do_syscall: arch/s390/kernel/syscall.c:147:9: warning: memcpy reading 64 bytes from a region of size 0 [-Wstringop-overread] 147 | memcpy(&regs->gprs[8], S390_lowcore.save_area_sync, 8 * sizeof(unsigned long)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/s390/kernel/syscall.c:148:9: warning: memcpy reading 4 bytes from a region of size 0 [-Wstringop-overread] 148 | memcpy(&regs->int_code, &S390_lowcore.svc_ilc, sizeof(regs->int_code)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by moving the gprs restore from C to assembly, and use a assignment for int_code instead of memcpy. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-05 22:01:09 +02:00
__u32 svc_int_code; /* 0x0088 */
s390/traps: get rid of magic cast for program interruption code Add a proper union in lowcore to reflect architecture and get rid of a "magic" cast in order to read the full program interruption code. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-03-06 11:15:27 +01:00
union {
struct {
__u16 pgm_ilc; /* 0x008c */
__u16 pgm_code; /* 0x008e */
};
__u32 pgm_int_code;
};
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u32 data_exc_code; /* 0x0090 */
__u16 mon_class_num; /* 0x0094 */
s390/traps: get rid of magic cast for per code Add a proper union in lowcore to reflect architecture and get rid of a "magic" cast in order to read the full per code. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-03-06 10:59:05 +01:00
union {
struct {
__u8 per_code; /* 0x0096 */
__u8 per_atmid; /* 0x0097 */
};
__u16 per_code_combined;
};
[S390] More cleanup for struct _lowcore Remove cpu_id from lowcore and replace addr_t with __u64. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-05-17 10:00:00 +02:00
__u64 per_address; /* 0x0098 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u8 exc_access_id; /* 0x00a0 */
__u8 per_access_id; /* 0x00a1 */
__u8 op_access_id; /* 0x00a2 */
s390: fix name of lowcore field at offset 0xa3 According to the Principles of Operation, at offset 0xA3 in the lowcore we have the "Architectural-Mode identification", not an "access identification". Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-02-10 10:55:37 +01:00
__u8 ar_mode_id; /* 0x00a3 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u8 pad_0x00a4[0x00a8-0x00a4]; /* 0x00a4 */
[S390] More cleanup for struct _lowcore Remove cpu_id from lowcore and replace addr_t with __u64. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-05-17 10:00:00 +02:00
__u64 trans_exc_code; /* 0x00a8 */
__u64 monitor_code; /* 0x00b0 */
s390: use struct tpi_info in lowcore.h Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-10 21:10:18 +02:00
union {
struct {
__u16 subchannel_id; /* 0x00b8 */
__u16 subchannel_nr; /* 0x00ba */
__u32 io_int_parm; /* 0x00bc */
__u32 io_int_word; /* 0x00c0 */
};
struct tpi_info tpi_info; /* 0x00b8 */
};
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u8 pad_0x00c4[0x00c8-0x00c4]; /* 0x00c4 */
__u32 stfl_fac_list; /* 0x00c8 */
__u8 pad_0x00cc[0x00e8-0x00cc]; /* 0x00cc */
s390/nmi: change type of mcck_interruption_code lowcore field For some unknown reason the mcck_interruption_code field is defined as array of two 32 bit values. Given that this actually is a 64 bit field according to the architecture, change the type to u64. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-06 14:45:35 +02:00
__u64 mcck_interruption_code; /* 0x00e8 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u8 pad_0x00f0[0x00f4-0x00f0]; /* 0x00f0 */
__u32 external_damage_code; /* 0x00f4 */
[S390] More cleanup for struct _lowcore Remove cpu_id from lowcore and replace addr_t with __u64. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-05-17 10:00:00 +02:00
__u64 failing_storage_address; /* 0x00f8 */
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
__u8 pad_0x0100[0x0110-0x0100]; /* 0x0100 */
s390: rename last_break to pgm_last_break With the upcoming BEAR enhancements last_break isn't really unique, so rename it to pgm_last_break. This way it should be more obvious that this is the last_break value that is written by the hardware when a program check occurs. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-10-01 17:08:09 +02:00
__u64 pgm_last_break; /* 0x0110 */
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
__u8 pad_0x0118[0x0120-0x0118]; /* 0x0118 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
psw_t restart_old_psw; /* 0x0120 */
psw_t external_old_psw; /* 0x0130 */
psw_t svc_old_psw; /* 0x0140 */
psw_t program_old_psw; /* 0x0150 */
psw_t mcck_old_psw; /* 0x0160 */
psw_t io_old_psw; /* 0x0170 */
__u8 pad_0x0180[0x01a0-0x0180]; /* 0x0180 */
psw_t restart_psw; /* 0x01a0 */
psw_t external_new_psw; /* 0x01b0 */
psw_t svc_new_psw; /* 0x01c0 */
psw_t program_new_psw; /* 0x01d0 */
psw_t mcck_new_psw; /* 0x01e0 */
psw_t io_new_psw; /* 0x01f0 */
[S390] entry[64].S improvements Another round of cleanup for entry[64].S, in particular the program check handler looks more reasonable now. The code size for the 31 bit kernel has been reduced by 616 byte and by 528 byte for the 64 bit version. Even better the code is a bit faster as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-27 11:27:15 +01:00
/* Save areas. */
s390/entry: Unify save_area_sync and save_area_async In the past two save areas existed because interrupt handlers and system call / program check handlers where entered with interrupts enabled. To prevent a handler from overwriting the save areas from the previous handler, interrupts used the async save area, while system call and program check handler used the sync save area. Since the removal of critical section cleanup from entry.S, handlers are entered with interrupts disabled. When the interrupts are re-enabled, the save area is no longer need. Therefore merge both save areas into one. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-08-28 13:50:04 +02:00
__u64 save_area[8]; /* 0x0200 */
__u8 pad_0x0240[0x0280-0x0240]; /* 0x0240 */
[S390] entry[64].S improvements Another round of cleanup for entry[64].S, in particular the program check handler looks more reasonable now. The code size for the 31 bit kernel has been reduced by 616 byte and by 528 byte for the 64 bit version. Even better the code is a bit faster as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-27 11:27:15 +01:00
__u64 save_area_restart[1]; /* 0x0280 */
s390: split TIF bits into CIF, PIF and TIF bits The oi and ni instructions used in entry[64].S to set and clear bits in the thread-flags are not guaranteed to be atomic in regard to other CPUs. Split the TIF bits into CPU, pt_regs and thread-info specific bits. Updates on the TIF bits are done with atomic instructions, updates on CPU and pt_regs bits are done with non-atomic instructions. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-04-15 12:55:07 +02:00
s390: Move CIF flags to struct pcpu To allow testing flags for offline CPUs, move the CIF flags to struct pcpu. To avoid having to calculate the array index for each access, add a pointer to the pcpu member for the current cpu to lowcore. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-16 09:26:15 +02:00
__u64 pcpu; /* 0x0288 */
[S390] entry[64].S improvements Another round of cleanup for entry[64].S, in particular the program check handler looks more reasonable now. The code size for the 31 bit kernel has been reduced by 616 byte and by 528 byte for the 64 bit version. Even better the code is a bit faster as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-27 11:27:15 +01:00
/* Return psws. */
psw_t return_psw; /* 0x0290 */
psw_t return_mcck_psw; /* 0x02a0 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
s390: add support for BEAR enhancement facility The Breaking-Event-Address-Register (BEAR) stores the address of the last breaking event instruction. Breaking events are usually instructions that change the program flow - for example branches, and instructions that modify the address in the PSW like lpswe. This is useful for debugging wild branches, because one could easily figure out where the wild branch was originating from. What is problematic is that lpswe is considered a breaking event, and therefore overwrites BEAR on kernel exit. The BEAR enhancement facility adds new instructions that allow to save/restore BEAR and also an lpswey instruction that doesn't cause a breaking event. So we can save BEAR on kernel entry and restore it on exit to user space. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-04-07 09:20:17 +02:00
__u64 last_break; /* 0x02b0 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
/* CPU accounting and timing values. */
s390: add support for BEAR enhancement facility The Breaking-Event-Address-Register (BEAR) stores the address of the last breaking event instruction. Breaking events are usually instructions that change the program flow - for example branches, and instructions that modify the address in the PSW like lpswe. This is useful for debugging wild branches, because one could easily figure out where the wild branch was originating from. What is problematic is that lpswe is considered a breaking event, and therefore overwrites BEAR on kernel exit. The BEAR enhancement facility adds new instructions that allow to save/restore BEAR and also an lpswey instruction that doesn't cause a breaking event. So we can save BEAR on kernel entry and restore it on exit to user space. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-04-07 09:20:17 +02:00
__u64 sys_enter_timer; /* 0x02b8 */
[S390] entry[64].S improvements Another round of cleanup for entry[64].S, in particular the program check handler looks more reasonable now. The code size for the 31 bit kernel has been reduced by 616 byte and by 528 byte for the 64 bit version. Even better the code is a bit faster as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-12-27 11:27:15 +01:00
__u64 mcck_enter_timer; /* 0x02c0 */
__u64 exit_timer; /* 0x02c8 */
__u64 user_timer; /* 0x02d0 */
sched/cputime, s390: Implement delayed accounting of system time The account_system_time() function is called with a cputime that occurred while running in the kernel. The function detects which context the CPU is currently running in and accounts the time to the correct bucket. This forces the arch code to account the cputime for hardirq and softirq immediately. Such accounting function can be costly and perform unwelcome divisions and multiplications, among others. The arch code can delay the accounting for system time. For s390 the accounting is done once per timer tick and for each task switch. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> [ Rebase against latest linus tree and move account_system_index_scaled(). ] Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1483636310-6557-10-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-05 18:11:49 +01:00
__u64 guest_timer; /* 0x02d8 */
__u64 system_timer; /* 0x02e0 */
__u64 hardirq_timer; /* 0x02e8 */
__u64 softirq_timer; /* 0x02f0 */
__u64 steal_timer; /* 0x02f8 */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u64 avg_steal_timer; /* 0x0300 */
__u64 last_update_timer; /* 0x0308 */
__u64 last_update_clock; /* 0x0310 */
s390/entry: remove mcck clock In the past machine checks where accounted as irq time. With the conversion to generic entry, it was decided to account machine checks to the current context. The stckf at the beginning of the machine check handler and the lowcore member is no longer required, therefore remove it. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-06-29 08:59:43 +02:00
__u64 int_clock; /* 0x0318 */
__u8 pad_0x0320[0x0328-0x0320]; /* 0x0320 */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u64 clock_comparator; /* 0x0328 */
s390/time: Convert MACHINE_HAS_SCC to machine_has_scc() Use static branch(es) to implement and use machine_has_scc() instead of a runtime check via MACHINE_HAS_SCC. This comes with a cleanup of early time initialization: the initial tod_clock_base value is now passed via the bootdata mechanism, instead of using absolute lowcore as transport vehicle from the decompressor to the kernel. Also the early tod clock initialization is moved to the decompressor which allows to use a static branch with machine_has_scc() within the kernel. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-07 15:48:59 +01:00
__u8 pad_0x0330[0x0340-0x0330]; /* 0x0330 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
/* Current process. */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u64 current_task; /* 0x0340 */
__u64 kernel_stack; /* 0x0348 */
[S390] rework smp code Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11 11:59:26 -04:00
s390: add support for virtually mapped kernel stacks With virtually mapped kernel stacks the kernel stack overflow detection is now fault based, every stack has a guard page in the vmalloc space. The panic_stack is renamed to nodat_stack and is used for all function that need to run without DAT, e.g. memcpy_real or do_start_kdump. The main effect is a reduction in the kernel image size as with vmap stacks the old style overflow checking that adds two instructions per function is not needed anymore. Result from bloat-o-meter: add/remove: 20/1 grow/shrink: 13/26854 up/down: 2198/-216240 (-214042) In regard to performance the micro-benchmark for fork has a hit of a few microseconds, allocating 4 pages in vmalloc space is more expensive compare to an order-2 page allocation. But with real workload I could not find a noticeable difference. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-09-12 16:37:33 +02:00
/* Interrupt, DAT-off and restartstack. */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u64 async_stack; /* 0x0350 */
__u64 nodat_stack; /* 0x0358 */
__u64 restart_stack; /* 0x0360 */
s390: add stack for machine check handler The previous code used the normal kernel stack for machine checks. This is problematic when a machine check interrupts a system call or interrupt handler right at the beginning where registers are set up. Assume system_call is interrupted at the first instruction and a machine check is triggered. The machine check handler is called, checks the PSW to see whether it is coming from user space, notices that it is already in kernel mode but %r15 still contains the user space stack. This would lead to a kernel crash. There are basically two ways of fixing that: Either using the 'critical cleanup' approach which compares the address in the PSW to see whether it is already at a point where the stack has been set up, or use an extra stack for the machine check handler. For simplicity, we will go with the second approach and allocate an extra stack. This adds some memory overhead for large systems, but usually large system have plenty of memory so this isn't really a concern. But it keeps the mchk stack setup simple and less error prone. Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Cc: <stable@kernel.org> # v5.8+ Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-03 09:02:51 +01:00
__u64 mcck_stack; /* 0x0368 */
[S390] rework smp code Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11 11:59:26 -04:00
/* Restart function and parameter. */
s390: add stack for machine check handler The previous code used the normal kernel stack for machine checks. This is problematic when a machine check interrupts a system call or interrupt handler right at the beginning where registers are set up. Assume system_call is interrupted at the first instruction and a machine check is triggered. The machine check handler is called, checks the PSW to see whether it is coming from user space, notices that it is already in kernel mode but %r15 still contains the user space stack. This would lead to a kernel crash. There are basically two ways of fixing that: Either using the 'critical cleanup' approach which compares the address in the PSW to see whether it is already at a point where the stack has been set up, or use an extra stack for the machine check handler. For simplicity, we will go with the second approach and allocate an extra stack. This adds some memory overhead for large systems, but usually large system have plenty of memory so this isn't really a concern. But it keeps the mchk stack setup simple and less error prone. Fixes: 0b0ed657fe00 ("s390: remove critical section cleanup from entry.S") Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Cc: <stable@kernel.org> # v5.8+ Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-02-03 09:02:51 +01:00
__u64 restart_fn; /* 0x0370 */
__u64 restart_data; /* 0x0378 */
s390/smp: enable DAT before CPU restart callback is called The restart interrupt is triggered whenever a secondary CPU is brought online, a remote function call dispatched from another CPU or a manual PSW restart is initiated and causes the system to kdump. The handling routine is always called with DAT turned off. It then initializes the stack frame and invokes a callback. The existing callbacks handle DAT as follows: * __do_restart() and __machine_kexec() turn in on upon entry; * __ipl_run(), __reipl_run() and __dump_run() do not turn it right away, but all of them call diag308() - which turns DAT on, but only if kasan is enabled; In addition to the described complexity all callbacks (and the functions they call) should avoid kasan instrumentation while DAT is off. This update enables DAT in the assembler restart handler and relieves any callbacks (which are mostly C functions) from dealing with DAT altogether. There are four types of CPU restart that initialize control registers in different ways: 1. Start of secondary CPU on boot - control registers are inherited from the IPL CPU; 2. Restart of online CPU - control registers of the CPU being restarted are kept; 3. Hotplug of offline CPU - control registers are inherited from the starting CPU; 4. Start of offline CPU triggered by manual PSW restart - the control registers are read from the absolute lowcore and contain the boot time IPL CPU values updated with all follow-up calls of smp_ctl_set_bit() and smp_ctl_clear_bit() routines; In first three cases contents of the control registers is the most recent. In the latter case control registers are good enough to facilitate successful completion of kdump operation. Suggested-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-24 15:30:21 +02:00
__u32 restart_source; /* 0x0380 */
__u32 restart_flags; /* 0x0384 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
/* Address space pointer. */
s390/ctlreg: add struct ctlreg Add struct ctlreg to enforce strict type checking / usage for control register functions. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-09-11 21:40:04 +02:00
struct ctlreg kernel_asce; /* 0x0388 */
struct ctlreg user_asce; /* 0x0390 */
s390/cpumf: rework program parameter setting to detect guest samples The program parameter can be used to mark hardware samples with some token. Previously, it was used to mark guest samples only. Improve the program parameter doubleword by combining two parts, the leftmost LPP part and the rightmost PID part. Set the PID part for processes by using the task PID. To distinguish host and guest samples for the kernel (PID part is zero), the guest must always set the program paramater to a non-zero value. Use the leftmost bit in the LPP part of the program parameter to be able to detect guest kernel samples. [brueckner@linux.vnet.ibm.com]: Split __LC_CURRENT and introduced __LC_LPP. Corrected __LC_CURRENT users and adjusted assembler parts. And updated the commit message accordingly. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-06 18:06:15 +02:00
/*
* The lpp and current_pid fields form a
* 64-bit value that is set as program
* parameter with the LPP instruction.
*/
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u32 lpp; /* 0x0398 */
__u32 current_pid; /* 0x039c */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
/* SMP info area */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u32 cpu_nr; /* 0x03a0 */
__u32 softirq_pending; /* 0x03a4 */
s390: fix clang -Wpointer-sign warnigns in boot code The arch/s390/boot directory is built with its own set of compiler options that does not include -Wno-pointer-sign like the rest of the kernel does, this causes a lot of harmless but correct warnings when building with clang. For the atomics, we can add type casts to avoid the warnings, for everything else the easiest way is to slightly adapt the types to be more consistent. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-15 10:35:54 +02:00
__s32 preempt_count; /* 0x03a8 */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u32 spinlock_lockval; /* 0x03ac */
__u32 spinlock_index; /* 0x03b0 */
s390/fpu: make kernel fpu context preemptible Make the kernel fpu context preemptible. Add another fpu structure to the thread_struct, and use it to save and restore the kernel fpu context if its task uses fpu registers when it is preempted. Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-03 11:45:12 +01:00
__u8 pad_0x03b4[0x03b8-0x03b4]; /* 0x03b4 */
s390/vtime: steal time exponential moving average To be able to judge the current overcommitment ratio for a CPU add a lowcore field with the exponential moving average of the steal time. The average is updated every tick. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-06 13:31:21 +02:00
__u64 percpu_offset; /* 0x03b8 */
s390/lowcore: Remove unused machine_flags The machine_flags member in struct lowcore is not used anymore. Remove it. Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-20 14:49:09 +01:00
__u8 pad_0x03c0[0x0400-0x03c0]; /* 0x03c0 */
s390: introduce execute-trampolines for branches Add CONFIG_EXPOLINE to enable the use of the new -mindirect-branch= and -mfunction_return= compiler options to create a kernel fortified against the specte v2 attack. With CONFIG_EXPOLINE=y all indirect branches will be issued with an execute type instruction. For z10 or newer the EXRL instruction will be used, for older machines the EX instruction. The typical indirect call basr %r14,%r1 is replaced with a PC relative call to a new thunk brasl %r14,__s390x_indirect_jump_r1 The thunk contains the EXRL/EX instruction to the indirect branch __s390x_indirect_jump_r1: exrl 0,0f j . 0: br %r1 The detour via the execute type instruction has a performance impact. To get rid of the detour the new kernel parameter "nospectre_v2" and "spectre_v2=[on,off,auto]" can be used. If the parameter is specified the kernel and module code will be patched at runtime. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-01-26 12:46:47 +01:00
s390: raise minimum supported machine generation to z10 Machine generations up to z9 (released in May 2006) have been officially out of service for several years now (z9 end of service - January 31, 2019). No distributions build kernels supporting those old machine generations anymore, except Debian, which seems to pick the oldest supported generation. The team supporting Debian on s390 has been notified about the change. Raising minimum supported machine generation to z10 helps to reduce maintenance cost and effectively remove code, which is not getting enough testing coverage due to lack of older hardware and distributions support. Besides that this unblocks some optimization opportunities and allows to use wider instruction set in asm files for future features implementation. Due to this change spectre mitigation and usercopy implementations could be drastically simplified and many newer instructions could be converted from ".insn" encoding to instruction names. Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-02-24 22:43:31 +01:00
__u32 return_lpswe; /* 0x0400 */
__u32 return_mcck_lpswe; /* 0x0404 */
__u8 pad_0x040a[0x0e00-0x0408]; /* 0x0408 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
/*
* 0xe00 contains the address of the IPL Parameter Information
* block. Dump tools need IPIB for IPL after dump.
* Note: do not change the position of any fields in 0x0e00-0x0f00
*/
__u64 ipib; /* 0x0e00 */
__u32 ipib_checksum; /* 0x0e08 */
s390/smp: make absolute lowcore / cpu restart parameter accesses more robust Setting the cpu restart parameters is done in three different fashions: - directly setting the four parameters individually - copying the four parameters with memcpy (using 4 * sizeof(long)) - copying the four parameters using a private structure In addition code in entry*.S relies on a certain order of the restart members of struct _lowcore. Make all of this more robust to future changes by adding a mem_absolute_assign(dest, val) define, which assigns val to dest using absolute addressing mode. Also the load multiple instructions in entry*.S have been split into separate load instruction so the order of the struct _lowcore members doesn't matter anymore. In addition move the prototypes of memcpy_real/absolute from uaccess.h to processor.h. These memcpy* variants are not related to uaccess at all. string.h doesn't seem to match as well, so lets use processor.h. Also replace the eight byte array in struct _lowcore which represents a misaliged u64 with a u64. The compiler will always create code that handles the misaligned u64 correctly. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-06-05 09:59:52 +02:00
__u64 vmcore_info; /* 0x0e0c */
[S390] kernel: Add OS info memory interface In order to allow kdump based stand-alone dump, some information has to be passed from the old kernel to the new dump kernel. This is done via a the struct "os_info" that contains the following fields: * crashkernel base and size * reipl block * vmcoreinfo * init function A pointer to os_info is stored at a well known storage location and the whole structure as well as all fields are secured with checksums. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-03-11 11:59:34 -04:00
__u8 pad_0x0e14[0x0e18-0x0e14]; /* 0x0e14 */
__u64 os_info; /* 0x0e18 */
s390/facilities: move stfl information from lowcore to global data With gcc-11, there are a lot of warnings because the facility functions are accessing lowcore through a null pointer. Fix this by moving the facility arrays away from lowcore. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-05 22:01:10 +02:00
__u8 pad_0x0e20[0x11b0-0x0e20]; /* 0x0e20 */
s390: add support for vector extension The vector extension introduces 32 128-bit vector registers and a set of instruction to operate on the vector registers. The kernel can control the use of vector registers for the problem state program with a bit in control register 0. Once enabled for a process the kernel needs to retain the content of the vector registers on context switch. The signal frame is extended to include the vector registers. Two new register sets NT_S390_VXRS_LOW and NT_S390_VXRS_HIGH are added to the regset interface for the debugger and core dumps. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-06 17:53:53 +02:00
s390: add a system call for guarded storage This adds a new system call to enable the use of guarded storage for user space processes. The system call takes two arguments, a command and pointer to a guarded storage control block: s390_guarded_storage(int command, struct gs_cb *gs_cb); The second argument is relevant only for the GS_SET_BC_CB command. The commands in detail: 0 - GS_ENABLE Enable the guarded storage facility for the current task. The initial content of the guarded storage control block will be all zeros. After the enablement the user space code can use load-guarded-storage-controls instruction (LGSC) to load an arbitrary control block. While a task is enabled the kernel will save and restore the current content of the guarded storage registers on context switch. 1 - GS_DISABLE Disables the use of the guarded storage facility for the current task. The kernel will cease to save and restore the content of the guarded storage registers, the task specific content of these registers is lost. 2 - GS_SET_BC_CB Set a broadcast guarded storage control block. This is called per thread and stores a specific guarded storage control block in the task struct of the current task. This control block will be used for the broadcast event GS_BROADCAST. 3 - GS_CLEAR_BC_CB Clears the broadcast guarded storage control block. The guarded- storage control block is removed from the task struct that was established by GS_SET_BC_CB. 4 - GS_BROADCAST Sends a broadcast to all thread siblings of the current task. Every sibling that has established a broadcast guarded storage control block will load this control block and will be enabled for guarded storage. The broadcast guarded storage control block is used up, a second broadcast without a refresh of the stored control block with GS_SET_BC_CB will not have any effect. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-26 14:10:34 +01:00
/* Pointer to the machine check extended save area */
__u64 mcesad; /* 0x11b0 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
/* 64 bit extparam used for pfault/diag 250: defined by architecture */
__u64 ext_params2; /* 0x11B8 */
__u8 pad_0x11c0[0x1200-0x11C0]; /* 0x11C0 */
/* CPU register save area: defined by architecture */
__u64 floating_pt_save_area[16]; /* 0x1200 */
__u64 gpregs_save_area[16]; /* 0x1280 */
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
psw_t psw_save_area; /* 0x1300 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u8 pad_0x1310[0x1318-0x1310]; /* 0x1310 */
__u32 prefixreg_save_area; /* 0x1318 */
__u32 fpt_creg_save_area; /* 0x131c */
__u8 pad_0x1320[0x1324-0x1320]; /* 0x1320 */
__u32 tod_progreg_save_area; /* 0x1324 */
__u32 cpu_timer_save_area[2]; /* 0x1328 */
__u32 clock_comp_save_area[2]; /* 0x1330 */
s390: add support for BEAR enhancement facility The Breaking-Event-Address-Register (BEAR) stores the address of the last breaking event instruction. Breaking events are usually instructions that change the program flow - for example branches, and instructions that modify the address in the PSW like lpswe. This is useful for debugging wild branches, because one could easily figure out where the wild branch was originating from. What is problematic is that lpswe is considered a breaking event, and therefore overwrites BEAR on kernel exit. The BEAR enhancement facility adds new instructions that allow to save/restore BEAR and also an lpswey instruction that doesn't cause a breaking event. So we can save BEAR on kernel entry and restore it on exit to user space. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-04-07 09:20:17 +02:00
__u64 last_break_save_area; /* 0x1338 */
[S390] cleanup lowcore.h The lowcore.h header has quite a lot of whitespace damage and a rather wild collection of entries. Remove all that whitespace and tidy up the order of the lowcore fields. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:44 +01:00
__u32 access_regs_save_area[16]; /* 0x1340 */
s390/ctlreg: add struct ctlreg Add struct ctlreg to enforce strict type checking / usage for control register functions. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-09-11 21:40:04 +02:00
struct ctlreg cregs_save_area[16]; /* 0x1380 */
s390/pai: add support for cryptography counters PMU device driver perf_pai_crypto supports Processor Activity Instrumentation (PAI), available with IBM z16: - maps a full page to lowcore address 0x1500. - uses CR0 bit 13 to turn PAI crypto counting on and off. - creates a sample with raw data on each context switch out when at context switch some mapped counters have a value of nonzero. This device driver only supports CPU wide context, no task context is allowed. Support for counting: - one or more counters can be specified using perf stat -e pai_crypto/xxx/ where xxx stands for the counter event name. Multiple invocation of this command is possible. The counter names are listed in /sys/devices/pai_crypto/events directory. - one special counters can be specified using perf stat -e pai_crypto/CRYPTO_ALL/ which returns the sum of all incremented crypto counters. - one event pai_crypto/CRYPTO_ALL/ is reserved for sampling. No multiple invocations are possible. The event collects data at context switch out and saves them in the ring buffer. Add qpaci assembly instruction to query supported memory mapped crypto counters. It returns the number of counters (no holes allowed in that range). The PAI crypto counter events are system wide and can not be executed in parallel. Therefore some restrictions documented in function paicrypt_busy apply. In particular event CRYPTO_ALL for sampling must run exclusive. Only counting events can run in parallel. PAI crypto counter events can not be created when a CPU hot plug add is processed. This means a CPU hot plug add does not get the necessary PAI event to record PAI cryptography counter increments on the newly added CPU. CPU hot plug remove removes the event and terminates the counting of PAI counters immediately. Co-developed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Link: https://lore.kernel.org/r/20220504062351.2954280-3-tmricht@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2022-05-04 08:23:51 +02:00
__u8 pad_0x1400[0x1500-0x1400]; /* 0x1400 */
/* Cryptography-counter designation */
__u64 ccd; /* 0x1500 */
s390/pai: Add support for PAI Extension 1 NNPA counters PMU device driver perf_paiext supports Processor Activity Instrumentation Extension (PAIE1), available with IBM z16: - maps a 512 byte block to lowcore address 0x1508 called PAIE1 control block. - maps a 1024 byte block at PAIE1 control block entry with index 2. - uses control register bit 14 to enable PAIE1 control block lookup. - turn PAIE1 nnpa counting on and off by setting bit 63 in PAIE1 control block entry with index 2. - creates a sample with raw data on each context switch out when at context switch some mapped counters have a value of nonzero. This device driver only supports CPU wide context, no task context is allowed. Support for counting: - one or more counters can be specified using perf stat -e pai_ext/xxx/ where xxx stands for the counter event name. Multiple invocation of this command is possible. The counter names are listed in /sys/devices/pai_ext/events directory. - one special counters can be specified using perf stat -e pai_ext/NNPA_ALL/ which returns the sum of all incremented nnpa counters. - multiple counting events can run in parallel. Support for Sampling: - one event pai_ext/NNPA_ALL/ is reserved for sampling. The event collects data at context switch out and saves them in the ring buffer. - no multiple invocations are possible. The PAIE1 nnpa counter events are system wide. No task context is supported. Therefore some restrictions documented in function paiext_busy() apply. Extend qpaci assembly instruction to query supported memory mapped nnpa counters. It returns the number of counters (no holes allowed in that range). PAIE1 nnpa counter events can not be created when a CPU hot plug add is processed. This means a CPU hot plug add does not get the necessary PAIE1 event to record PAIE1 nnpa counter increments on the newly added CPU. CPU hot plug remove removes the event and terminates the counting of PAIE1 counters immediately. Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Reviewed-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-06-30 11:53:48 +02:00
/* AI-extension counter designation */
__u64 aicd; /* 0x1508 */
__u8 pad_0x1510[0x1800-0x1510]; /* 0x1510 */
s390: add support for transactional memory Allow user-space processes to use transactional execution (TX). If the TX facility is available user space programs can use transactions for fine-grained serialization based on the data objects that are referenced during a transaction. This is useful for lockless data structures and speculative compiler optimizations. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-07-31 11:03:04 +02:00
/* Transaction abort diagnostic block */
s390/traps: add struct to access transactional diagnostic block gcc-11 warns: arch/s390/kernel/traps.c: In function __do_pgm_check: arch/s390/kernel/traps.c:319:17: warning: memcpy reading 256 bytes from a region of size 0 [-Wstringop-overread] 319 | memcpy(&current->thread.trap_tdb, &S390_lowcore.pgm_tdb, 256); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by adding a struct pgm_tdb to struct lowcore and copy that. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-05-05 22:01:16 +02:00
struct pgm_tdb pgm_tdb; /* 0x1800 */
s390: add a system call for guarded storage This adds a new system call to enable the use of guarded storage for user space processes. The system call takes two arguments, a command and pointer to a guarded storage control block: s390_guarded_storage(int command, struct gs_cb *gs_cb); The second argument is relevant only for the GS_SET_BC_CB command. The commands in detail: 0 - GS_ENABLE Enable the guarded storage facility for the current task. The initial content of the guarded storage control block will be all zeros. After the enablement the user space code can use load-guarded-storage-controls instruction (LGSC) to load an arbitrary control block. While a task is enabled the kernel will save and restore the current content of the guarded storage registers on context switch. 1 - GS_DISABLE Disables the use of the guarded storage facility for the current task. The kernel will cease to save and restore the content of the guarded storage registers, the task specific content of these registers is lost. 2 - GS_SET_BC_CB Set a broadcast guarded storage control block. This is called per thread and stores a specific guarded storage control block in the task struct of the current task. This control block will be used for the broadcast event GS_BROADCAST. 3 - GS_CLEAR_BC_CB Clears the broadcast guarded storage control block. The guarded- storage control block is removed from the task struct that was established by GS_SET_BC_CB. 4 - GS_BROADCAST Sends a broadcast to all thread siblings of the current task. Every sibling that has established a broadcast guarded storage control block will load this control block and will be enabled for guarded storage. The broadcast guarded storage control block is used up, a second broadcast without a refresh of the stored control block with GS_SET_BC_CB will not have any effect. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-26 14:10:34 +01:00
__u8 pad_0x1900[0x2000-0x1900]; /* 0x1900 */
s390: align struct lowcore to double page size Aligning struct lowcore to double page size allows to get rid of this gcc warning: In file included from ./arch/s390/include/asm/setup.h:56, from ./arch/s390/include/asm/page.h:36, from ./arch/s390/include/asm/user.h:11, from ./include/linux/user.h:1, from ./include/linux/elfcore.h:5, from ./include/linux/crash_core.h:6, from ./include/linux/kexec.h:18, from arch/s390/purgatory/purgatory.c:10: ./arch/s390/include/asm/lowcore.h:189:1: warning: alignment 1 of 'struct lowcore' is less than 8 [-Wpacked-not-aligned] } __packed; Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-28 13:12:27 +02:00
} __packed __aligned(8192);
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
s390: Add get_lowcore() function Add a get_lowcore() function which returns the address of lowcore (currently always NULL). This function will be used as a replacement of the S390_lowcore macro. Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-06-10 13:45:24 +02:00
static __always_inline struct lowcore *get_lowcore(void)
{
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
struct lowcore *lc;
if (__is_defined(__DECOMPRESSOR))
return NULL;
s390/lowcore: Use inline qualifier for get_lowcore() inline assembly Use asm_inline to let the compiler know that the get_lowcore() inline assembly has the smallest possible size. The ALTERNATIVE construct is used to generate a single instruction, however the macro expands to multiple lines. GCC uses the number of lines of an inline assembly to count the number of instructions within an inline assembly, which then has an effect on inlining decisions. In order to avoid incorrect assumptions use asm_inline. The result is that more functions are inlined, which results in a small growth of the kernel image: add/remove: 59/480 grow/shrink: 854/647 up/down: 168780/-162394 (6386) Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-10 10:33:38 +01:00
asm_inline(
s390/lowcore: Use lghi instead llilh to clear register lghi is the fastest way to clear a register. Use that intead of llilh. Suggested-by: Juergen Christ <jchrist@linux.ibm.com> Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-10 10:33:43 +01:00
ALTERNATIVE(" lghi %[lc],0",
s390/lowcore: Use inline qualifier for get_lowcore() inline assembly Use asm_inline to let the compiler know that the get_lowcore() inline assembly has the smallest possible size. The ALTERNATIVE construct is used to generate a single instruction, however the macro expands to multiple lines. GCC uses the number of lines of an inline assembly to count the number of instructions within an inline assembly, which then has an effect on inlining decisions. In order to avoid incorrect assumptions use asm_inline. The result is that more functions are inlined, which results in a small growth of the kernel image: add/remove: 59/480 grow/shrink: 854/647 up/down: 168780/-162394 (6386) Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-10 10:33:38 +01:00
" llilh %[lc],%[alt]",
ALT_FEATURE(MFEATURE_LOWCORE))
: [lc] "=d" (lc)
: [alt] "i" (LOWCORE_ALT_ADDRESS >> 16));
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
return lc;
s390: Add get_lowcore() function Add a get_lowcore() function which returns the address of lowcore (currently always NULL). This function will be used as a replacement of the S390_lowcore macro. Acked-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-06-10 13:45:24 +02:00
}
s390: rename struct _lowcore to struct lowcore Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-12-31 10:29:00 +01:00
extern struct lowcore *lowcore_ptr[];
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
[PATCH] s390: "extern inline" -> "static inline" "extern inline" -> "static inline" Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-08 21:34:42 -08:00
static inline void set_prefix(__u32 address)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
{
s390: correct some inline assembly constraints Inline assembly code changed in this patch should really use "Q" constraint "Memory reference without index register and with short displacement". The kernel does not compile with kasan support enabled otherwise (due to stack instrumentation). Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-11-13 16:37:33 +01:00
asm volatile("spx %0" : : "Q" (address) : "memory");
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 15:20:36 -07:00
}
s390: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembler code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This is bad since macros starting with two underscores are names that are reserved by the C language. It can also be very confusing for the developers when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's now standardize on the __ASSEMBLER__ macro that is provided by the compilers. This is a completely mechanical patch (done with a simple "sed -i" statement), with some manual fixups done later while rebasing the patch. Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20250611140046.137739-3-thuth@redhat.com Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-11 16:00:46 +02:00
#else /* __ASSEMBLER__ */
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
.macro GET_LC reg
s390/lowcore: Use lghi instead llilh to clear register lghi is the fastest way to clear a register. Use that intead of llilh. Suggested-by: Juergen Christ <jchrist@linux.ibm.com> Reviewed-by: Juergen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-10 10:33:43 +01:00
ALTERNATIVE "lghi \reg,0", \
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
__stringify(llilh \reg, LOWCORE_ALT_ADDRESS >> 16), \
s390/lowcore: Convert relocated lowcore alternative to machine feature Convert the explicit relocated lowcore alternative type to a more generic machine feature. This only reduces the number of alternative types, but has no impact on code generation. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-07 15:48:57 +01:00
ALT_FEATURE(MFEATURE_LOWCORE)
s390: Add infrastructure to patch lowcore accesses The s390 architecture defines two special per-CPU data pages called the "prefix area". In s390-linux terminology this is usually called "lowcore". This memory area contains system configuration data like old/new PSW's for system call/interrupt/machine check handlers and lots of other data. It is normally mapped to logical address 0. This area can only be accessed when in supervisor mode. This means that kernel code can dereference NULL pointers, because accesses to address 0 are allowed. Parts of lowcore can be write protected, but read accesses and write accesses outside of the write protected areas are not caught. To remove this limitation for debugging and testing, remap lowcore to another address and define a function get_lowcore() which simply returns the address where lowcore is mapped at. This would normally introduce a pointer dereference (=memory read). As lowcore is used for several very often used variables, add code to patch this function during runtime, so we avoid the memory reads. For C code get_lowcore() has to be used, for assembly code it is the GET_LC macro. When using this macro/function a reference is added to alternative patching. All these locations will be patched to the actual lowcore location when the kernel is booted or a module is loaded. To make debugging/bisecting problems easier, this patch adds all the infrastructure but the lowcore address is still hardwired to 0. This way the code can be converted on a per function basis, and the functionality is enabled in a patch after all the functions have been converted. Note that this requires at least z16 because the old lpsw instruction only allowed a 12 bit displacement. z16 introduced lpswey which allows 20 bits (signed), so the lowcore can effectively be mapped from address 0 - 0x7e000. To use 0x7e000 as address, a 6 byte lgfi instruction would have to be used in the alternative. To save two bytes, llilh can be used, but this only allows to set bits 16-31 of the address. In order to use the llilh instruction, use 0x70000 as alternative lowcore address. This is still large enough to catch NULL pointer dereferences into large arrays. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:14 +02:00
.endm
s390/entry: Make pgm_check_handler() ready for lowcore relocation In preparation of having lowcore at different address than zero, add the base register to all lowcore accesses in pgm_check_handler(). Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:20 +02:00
.macro STMG_LC start, end, savearea
ALTERNATIVE "stmg \start, \end, \savearea", \
__stringify(stmg \start, \end, LOWCORE_ALT_ADDRESS + \savearea), \
s390/lowcore: Convert relocated lowcore alternative to machine feature Convert the explicit relocated lowcore alternative type to a more generic machine feature. This only reduces the number of alternative types, but has no impact on code generation. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-07 15:48:57 +01:00
ALT_FEATURE(MFEATURE_LOWCORE)
s390/entry: Make pgm_check_handler() ready for lowcore relocation In preparation of having lowcore at different address than zero, add the base register to all lowcore accesses in pgm_check_handler(). Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2024-07-22 15:41:20 +02:00
.endm
s390: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembler code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This is bad since macros starting with two underscores are names that are reserved by the C language. It can also be very confusing for the developers when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's now standardize on the __ASSEMBLER__ macro that is provided by the compilers. This is a completely mechanical patch (done with a simple "sed -i" statement), with some manual fixups done later while rebasing the patch. Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20250611140046.137739-3-thuth@redhat.com Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-11 16:00:46 +02:00
#endif /* __ASSEMBLER__ */
[S390] Cleanup struct _lowcore usage and defines. Use asm offsets to make sure the offset defines to struct _lowcore and its layout don't get out of sync. Also add a BUILD_BUG_ON() which checks that the size of the structure is sane. And while being at it change those sites which use odd casts to access the current lowcore. These should use S390_lowcore instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:43 +01:00
#endif /* _ASM_S390_LOWCORE_H */
Reference in a new issue Copy permalink