public-mirrors/linux
1
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-05-24 10:39:52 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions
linux/arch/powerpc/include/asm/livepatch.h

32 lines
814 B
C
Raw Normal View History

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details [based] [from] [clk] [highbank] [c] you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 355 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-19 15:51:43 +02:00
/* SPDX-License-Identifier: GPL-2.0-or-later */
powerpc/livepatch: Add livepatch header Add the powerpc specific livepatch definitions. In particular we provide a non-default implementation of klp_get_ftrace_location(). This is required because the location of the mcount call is not constant when using -mprofile-kernel (which we always do for live patching). Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-24 22:04:03 +11:00
/*
* livepatch.h - powerpc-specific Kernel Live Patching Core
*
* Copyright (C) 2015-2016, SUSE, IBM Corp.
*/
#ifndef _ASM_POWERPC_LIVEPATCH_H
#define _ASM_POWERPC_LIVEPATCH_H
#include <linux/module.h>
#include <linux/ftrace.h>
powerpc: Activate CONFIG_THREAD_INFO_IN_TASK This patch activates CONFIG_THREAD_INFO_IN_TASK which moves the thread_info into task_struct. Moving thread_info into task_struct has the following advantages: - It protects thread_info from corruption in the case of stack overflows. - Its address is harder to determine if stack addresses are leaked, making a number of attacks more difficult. This has the following consequences: - thread_info is now located at the beginning of task_struct. - The 'cpu' field is now in task_struct, and only exists when CONFIG_SMP is active. - thread_info doesn't have anymore the 'task' field. This patch: - Removes all recopy of thread_info struct when the stack changes. - Changes the CURRENT_THREAD_INFO() macro to point to current. - Selects CONFIG_THREAD_INFO_IN_TASK. - Modifies raw_smp_processor_id() to get ->cpu from current without including linux/sched.h to avoid circular inclusion and without including asm/asm-offsets.h to avoid symbol names duplication between ASM constants and C constants. - Modifies klp_init_thread_info() to take a task_struct pointer argument. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add task_stack.h to livepatch.h to fix build fails] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-31 10:08:58 +00:00
#include <linux/sched/task_stack.h>
powerpc/livepatch: Add livepatch header Add the powerpc specific livepatch definitions. In particular we provide a non-default implementation of klp_get_ftrace_location(). This is required because the location of the mcount call is not constant when using -mprofile-kernel (which we always do for live patching). Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-24 22:04:03 +11:00
#ifdef CONFIG_LIVEPATCH
livepatch: Use the default ftrace_ops instead of REGS when ARGS is available When CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS is available, the ftrace call will be able to set the ip of the calling function. This will improve the performance of live kernel patching where it does not need all the regs to be stored just to change the instruction pointer. If all archs that support live kernel patching also support HAVE_DYNAMIC_FTRACE_WITH_ARGS, then the architecture specific function klp_arch_set_pc() could be made generic. It is possible that an arch can support HAVE_DYNAMIC_FTRACE_WITH_ARGS but not HAVE_DYNAMIC_FTRACE_WITH_REGS and then have access to live patching. Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: live-patching@vger.kernel.org Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-28 17:15:27 -04:00
static inline void klp_arch_set_pc(struct ftrace_regs *fregs, unsigned long ip)
powerpc/livepatch: Add livepatch header Add the powerpc specific livepatch definitions. In particular we provide a non-default implementation of klp_get_ftrace_location(). This is required because the location of the mcount call is not constant when using -mprofile-kernel (which we always do for live patching). Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-24 22:04:03 +11:00
{
powerpc/ftrace: Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS. It accelerates the call of livepatching. Also note that powerpc being the last one to convert to CONFIG_DYNAMIC_FTRACE_WITH_ARGS, it will now be possible to remove klp_arch_set_pc() on all architectures. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/5831f711a778fcd6eb51eb5898f1faae4378b35b.1640017960.git.christophe.leroy@csgroup.eu
2021-12-20 16:38:28 +00:00
ftrace_instruction_pointer_set(fregs, ip);
powerpc/livepatch: Add livepatch header Add the powerpc specific livepatch definitions. In particular we provide a non-default implementation of klp_get_ftrace_location(). This is required because the location of the mcount call is not constant when using -mprofile-kernel (which we always do for live patching). Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-24 22:04:03 +11:00
}
powerpc: restore removed #endif Fixes: 7001052160d1 ("Merge tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Brown-paper-bag-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-28 08:55:39 +11:00
#endif /* CONFIG_LIVEPATCH */
powerpc/livepatch: Add livepatch header Add the powerpc specific livepatch definitions. In particular we provide a non-default implementation of klp_get_ftrace_location(). This is required because the location of the mcount call is not constant when using -mprofile-kernel (which we always do for live patching). Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-24 22:04:03 +11:00
powerpc/ftrace: Add support for livepatch to PPC32 PPC64 needs some special logic to properly set up the TOC. See commit 85baa095497f ("powerpc/livepatch: Add live patching support on ppc64le") for details. PPC32 doesn't have TOC so it doesn't need that logic, so adding LIVEPATCH support is straight forward. Add CONFIG_LIVEPATCH_64 and move livepatch stack logic into that item. Livepatch sample modules all work. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/63cb094125b6a6038c65eeac2abaabbabe63addd.1640017960.git.christophe.leroy@csgroup.eu
2021-12-20 16:38:12 +00:00
#ifdef CONFIG_LIVEPATCH_64
powerpc: Activate CONFIG_THREAD_INFO_IN_TASK This patch activates CONFIG_THREAD_INFO_IN_TASK which moves the thread_info into task_struct. Moving thread_info into task_struct has the following advantages: - It protects thread_info from corruption in the case of stack overflows. - Its address is harder to determine if stack addresses are leaked, making a number of attacks more difficult. This has the following consequences: - thread_info is now located at the beginning of task_struct. - The 'cpu' field is now in task_struct, and only exists when CONFIG_SMP is active. - thread_info doesn't have anymore the 'task' field. This patch: - Removes all recopy of thread_info struct when the stack changes. - Changes the CURRENT_THREAD_INFO() macro to point to current. - Selects CONFIG_THREAD_INFO_IN_TASK. - Modifies raw_smp_processor_id() to get ->cpu from current without including linux/sched.h to avoid circular inclusion and without including asm/asm-offsets.h to avoid symbol names duplication between ASM constants and C constants. - Modifies klp_init_thread_info() to take a task_struct pointer argument. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add task_stack.h to livepatch.h to fix build fails] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-31 10:08:58 +00:00
static inline void klp_init_thread_info(struct task_struct *p)
powerpc/livepatch: Add livepatch stack to struct thread_info In order to support live patching we need to maintain an alternate stack of TOC & LR values. We use the base of the stack for this, and store the "live patch stack pointer" in struct thread_info. Unlike the other fields of thread_info, we can not statically initialise that value, so it must be done at run time. This patch just adds the code to support that, it is not enabled until the next patch which actually adds live patch support. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Balbir Singh <bsingharora@gmail.com>
2016-03-24 22:04:04 +11:00
{
/* + 1 to account for STACK_END_MAGIC */
powerpc: Activate CONFIG_THREAD_INFO_IN_TASK This patch activates CONFIG_THREAD_INFO_IN_TASK which moves the thread_info into task_struct. Moving thread_info into task_struct has the following advantages: - It protects thread_info from corruption in the case of stack overflows. - Its address is harder to determine if stack addresses are leaked, making a number of attacks more difficult. This has the following consequences: - thread_info is now located at the beginning of task_struct. - The 'cpu' field is now in task_struct, and only exists when CONFIG_SMP is active. - thread_info doesn't have anymore the 'task' field. This patch: - Removes all recopy of thread_info struct when the stack changes. - Changes the CURRENT_THREAD_INFO() macro to point to current. - Selects CONFIG_THREAD_INFO_IN_TASK. - Modifies raw_smp_processor_id() to get ->cpu from current without including linux/sched.h to avoid circular inclusion and without including asm/asm-offsets.h to avoid symbol names duplication between ASM constants and C constants. - Modifies klp_init_thread_info() to take a task_struct pointer argument. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add task_stack.h to livepatch.h to fix build fails] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-31 10:08:58 +00:00
task_thread_info(p)->livepatch_sp = end_of_stack(p) + 1;
powerpc/livepatch: Add livepatch stack to struct thread_info In order to support live patching we need to maintain an alternate stack of TOC & LR values. We use the base of the stack for this, and store the "live patch stack pointer" in struct thread_info. Unlike the other fields of thread_info, we can not statically initialise that value, so it must be done at run time. This patch just adds the code to support that, it is not enabled until the next patch which actually adds live patch support. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Balbir Singh <bsingharora@gmail.com>
2016-03-24 22:04:04 +11:00
}
#else
powerpc: Activate CONFIG_THREAD_INFO_IN_TASK This patch activates CONFIG_THREAD_INFO_IN_TASK which moves the thread_info into task_struct. Moving thread_info into task_struct has the following advantages: - It protects thread_info from corruption in the case of stack overflows. - Its address is harder to determine if stack addresses are leaked, making a number of attacks more difficult. This has the following consequences: - thread_info is now located at the beginning of task_struct. - The 'cpu' field is now in task_struct, and only exists when CONFIG_SMP is active. - thread_info doesn't have anymore the 'task' field. This patch: - Removes all recopy of thread_info struct when the stack changes. - Changes the CURRENT_THREAD_INFO() macro to point to current. - Selects CONFIG_THREAD_INFO_IN_TASK. - Modifies raw_smp_processor_id() to get ->cpu from current without including linux/sched.h to avoid circular inclusion and without including asm/asm-offsets.h to avoid symbol names duplication between ASM constants and C constants. - Modifies klp_init_thread_info() to take a task_struct pointer argument. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Add task_stack.h to livepatch.h to fix build fails] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-31 10:08:58 +00:00
static inline void klp_init_thread_info(struct task_struct *p) { }
powerpc/ftrace: Add support for livepatch to PPC32 PPC64 needs some special logic to properly set up the TOC. See commit 85baa095497f ("powerpc/livepatch: Add live patching support on ppc64le") for details. PPC32 doesn't have TOC so it doesn't need that logic, so adding LIVEPATCH support is straight forward. Add CONFIG_LIVEPATCH_64 and move livepatch stack logic into that item. Livepatch sample modules all work. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/63cb094125b6a6038c65eeac2abaabbabe63addd.1640017960.git.christophe.leroy@csgroup.eu
2021-12-20 16:38:12 +00:00
#endif
powerpc/livepatch: Add livepatch header Add the powerpc specific livepatch definitions. In particular we provide a non-default implementation of klp_get_ftrace_location(). This is required because the location of the mcount call is not constant when using -mprofile-kernel (which we always do for live patching). Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-24 22:04:03 +11:00
#endif /* _ASM_POWERPC_LIVEPATCH_H */
Reference in a new issue Copy permalink