diff options
| author | Kees Cook <keescook@chromium.org> | 2022-02-19 17:26:00 -0800 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2022-02-25 18:21:23 -0800 |
| commit | 92652cf986441b18282db6e5bd82afc74e8ed5e9 (patch) | |
| tree | 7d2cab1235f3216501ef6a499575872083bab455 /arch | |
| parent | 2792d84e6da5e0fd7d3b22fd70bc69b7ee263609 (diff) | |
xtensa: Implement "current_stack_pointer"
To follow the existing per-arch conventions replace open-coded uses
of asm "sp" as "current_stack_pointer". This will let it be used in
non-arch places (like HARDENED_USERCOPY).
Cc: Chris Zankel <chris@zankel.net>
Cc: Marc Zyngier <maz@kernel.org>
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Link: https://lore.kernel.org/lkml/CAMo8BfJFJE-n3=AF+pb9_6oF3gzxX7a+7aBrASHjjNX5byqDqw@mail.gmail.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/xtensa/Kconfig | 1 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/current.h | 2 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/stacktrace.h | 8 | ||||
| -rw-r--r-- | arch/xtensa/kernel/irq.c | 3 |
4 files changed, 8 insertions, 6 deletions
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 8ac599aa6d99..887432327613 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -3,6 +3,7 @@ config XTENSA def_bool y select ARCH_32BIT_OFF_T select ARCH_HAS_BINFMT_FLAT if !MMU + select ARCH_HAS_CURRENT_STACK_POINTER select ARCH_HAS_DMA_PREP_COHERENT if MMU select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU diff --git a/arch/xtensa/include/asm/current.h b/arch/xtensa/include/asm/current.h index 5d98a7ad4251..08010dbf5e09 100644 --- a/arch/xtensa/include/asm/current.h +++ b/arch/xtensa/include/asm/current.h @@ -26,6 +26,8 @@ static inline struct task_struct *get_current(void) #define current get_current() +register unsigned long current_stack_pointer __asm__("a1"); + #else #define GET_CURRENT(reg,sp) \ diff --git a/arch/xtensa/include/asm/stacktrace.h b/arch/xtensa/include/asm/stacktrace.h index fe06e8ed162b..a85e785a6288 100644 --- a/arch/xtensa/include/asm/stacktrace.h +++ b/arch/xtensa/include/asm/stacktrace.h @@ -19,14 +19,14 @@ struct stackframe { static __always_inline unsigned long *stack_pointer(struct task_struct *task) { - unsigned long *sp; + unsigned long sp; if (!task || task == current) - __asm__ __volatile__ ("mov %0, a1\n" : "=a"(sp)); + sp = current_stack_pointer; else - sp = (unsigned long *)task->thread.sp; + sp = task->thread.sp; - return sp; + return (unsigned long *)sp; } void walk_stackframe(unsigned long *sp, diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c index 15051a8a1539..529fe9245821 100644 --- a/arch/xtensa/kernel/irq.c +++ b/arch/xtensa/kernel/irq.c @@ -36,9 +36,8 @@ asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs) #ifdef CONFIG_DEBUG_STACKOVERFLOW /* Debugging check for stack overflow: is there less than 1KB free? */ { - unsigned long sp; + unsigned long sp = current_stack_pointer; - __asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp)); sp &= THREAD_SIZE - 1; if (unlikely(sp < (sizeof(thread_info) + 1024))) |