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linux/arch/parisc/include/asm/vdso.h

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parisc: Add vDSO support Add minimal vDSO support, which provides the signal trampoline helpers, but none of the userspace syscall helpers like time wrappers. The big benefit of this vDSO implementation is, that we now don't need an executeable stack any longer. PA-RISC is one of the last architectures where an executeable stack was needed in oder to implement the signal trampolines by putting assembly instructions on the stack which then gets executed. Instead the kernel will provide the relevant code in the vDSO page and only put the pointers to the signal information on the stack. By dropping the need for executable stacks we avoid running into issues with applications which want non executable stacks for security reasons. Additionally, alternative stacks on memory areas without exec permissions are supported too. This code is based on an initial implementation by Randolph Chung from 2006: https://lore.kernel.org/linux-parisc/4544A34A.6080700@tausq.org/ I did the porting and lifted the code to current code base. Dave fixed the unwind code so that gdb and glibc are able to backtrace through the code. An additional patch to gdb will be pushed upstream by Dave. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Dave Anglin <dave.anglin@bell.net> Cc: Randolph Chung <randolph@tausq.org> Signed-off-by: Helge Deller <deller@gmx.de>
2021-12-08 11:06:52 +01:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __PARISC_VDSO_H__
#define __PARISC_VDSO_H__
parisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize on the __ASSEMBLER__ macro that is provided by the compilers now. This is mostly a completely mechanical patch (done with a simple "sed -i" statement), except for some manual tweaks in the files arch/parisc/include/asm/smp.h, arch/parisc/include/asm/signal.h, arch/parisc/include/asm/thread_info.h and arch/parisc/include/asm/vdso.h that had the macro spelled in a wrong way. Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Helge Deller <deller@gmx.de>
2025-03-14 08:09:56 +01:00
#ifndef __ASSEMBLER__
parisc: Add vDSO support Add minimal vDSO support, which provides the signal trampoline helpers, but none of the userspace syscall helpers like time wrappers. The big benefit of this vDSO implementation is, that we now don't need an executeable stack any longer. PA-RISC is one of the last architectures where an executeable stack was needed in oder to implement the signal trampolines by putting assembly instructions on the stack which then gets executed. Instead the kernel will provide the relevant code in the vDSO page and only put the pointers to the signal information on the stack. By dropping the need for executable stacks we avoid running into issues with applications which want non executable stacks for security reasons. Additionally, alternative stacks on memory areas without exec permissions are supported too. This code is based on an initial implementation by Randolph Chung from 2006: https://lore.kernel.org/linux-parisc/4544A34A.6080700@tausq.org/ I did the porting and lifted the code to current code base. Dave fixed the unwind code so that gdb and glibc are able to backtrace through the code. An additional patch to gdb will be pushed upstream by Dave. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Dave Anglin <dave.anglin@bell.net> Cc: Randolph Chung <randolph@tausq.org> Signed-off-by: Helge Deller <deller@gmx.de>
2021-12-08 11:06:52 +01:00
#ifdef CONFIG_64BIT
#include <generated/vdso64-offsets.h>
#endif
#include <generated/vdso32-offsets.h>
#define VDSO64_SYMBOL(tsk, name) ((tsk)->mm->context.vdso_base + (vdso64_offset_##name))
#define VDSO32_SYMBOL(tsk, name) ((tsk)->mm->context.vdso_base + (vdso32_offset_##name))
parisc: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-uapi headers While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize on the __ASSEMBLER__ macro that is provided by the compilers now. This is mostly a completely mechanical patch (done with a simple "sed -i" statement), except for some manual tweaks in the files arch/parisc/include/asm/smp.h, arch/parisc/include/asm/signal.h, arch/parisc/include/asm/thread_info.h and arch/parisc/include/asm/vdso.h that had the macro spelled in a wrong way. Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: linux-parisc@vger.kernel.org Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Helge Deller <deller@gmx.de>
2025-03-14 08:09:56 +01:00
#endif /* __ASSEMBLER__ */
parisc: Add vDSO support Add minimal vDSO support, which provides the signal trampoline helpers, but none of the userspace syscall helpers like time wrappers. The big benefit of this vDSO implementation is, that we now don't need an executeable stack any longer. PA-RISC is one of the last architectures where an executeable stack was needed in oder to implement the signal trampolines by putting assembly instructions on the stack which then gets executed. Instead the kernel will provide the relevant code in the vDSO page and only put the pointers to the signal information on the stack. By dropping the need for executable stacks we avoid running into issues with applications which want non executable stacks for security reasons. Additionally, alternative stacks on memory areas without exec permissions are supported too. This code is based on an initial implementation by Randolph Chung from 2006: https://lore.kernel.org/linux-parisc/4544A34A.6080700@tausq.org/ I did the porting and lifted the code to current code base. Dave fixed the unwind code so that gdb and glibc are able to backtrace through the code. An additional patch to gdb will be pushed upstream by Dave. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Dave Anglin <dave.anglin@bell.net> Cc: Randolph Chung <randolph@tausq.org> Signed-off-by: Helge Deller <deller@gmx.de>
2021-12-08 11:06:52 +01:00
/* Default link addresses for the vDSOs */
#define VDSO_LBASE 0
parisc: Add 32-bit gettimeofday() and clock_gettime() vDSO functions Add vDSO implementations for gettimeofday(), clock_gettime() and clock_gettime64() kernel syscalls. Currently those functions are implemented as pure syscall wrappers. Signed-off-by: Helge Deller <deller@gmx.de>
2024-06-19 01:42:28 +02:00
#define VDSO_VERSION_STRING LINUX_6.11
parisc: Add vDSO support Add minimal vDSO support, which provides the signal trampoline helpers, but none of the userspace syscall helpers like time wrappers. The big benefit of this vDSO implementation is, that we now don't need an executeable stack any longer. PA-RISC is one of the last architectures where an executeable stack was needed in oder to implement the signal trampolines by putting assembly instructions on the stack which then gets executed. Instead the kernel will provide the relevant code in the vDSO page and only put the pointers to the signal information on the stack. By dropping the need for executable stacks we avoid running into issues with applications which want non executable stacks for security reasons. Additionally, alternative stacks on memory areas without exec permissions are supported too. This code is based on an initial implementation by Randolph Chung from 2006: https://lore.kernel.org/linux-parisc/4544A34A.6080700@tausq.org/ I did the porting and lifted the code to current code base. Dave fixed the unwind code so that gdb and glibc are able to backtrace through the code. An additional patch to gdb will be pushed upstream by Dave. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Dave Anglin <dave.anglin@bell.net> Cc: Randolph Chung <randolph@tausq.org> Signed-off-by: Helge Deller <deller@gmx.de>
2021-12-08 11:06:52 +01:00
#endif /* __PARISC_VDSO_H__ */
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