diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2019-05-07 23:25:54 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2019-06-25 10:23:47 +0200 |
| commit | 3c88c692c28746473791276f8b42d2c989d6cbe6 (patch) | |
| tree | 51cb03ef4cbb611f42ea43c8737be894991b656b /arch/x86/kernel/time.c | |
| parent | ea1ed38dba64b64a245ab8ca1406269d17b99485 (diff) | |
x86/stackframe/32: Provide consistent pt_regs
Currently pt_regs on x86_32 has an oddity in that kernel regs
(!user_mode(regs)) are short two entries (esp/ss). This means that any
code trying to use them (typically: regs->sp) needs to jump through
some unfortunate hoops.
Change the entry code to fix this up and create a full pt_regs frame.
This then simplifies various trampolines in ftrace and kprobes, the
stack unwinder, ptrace, kdump and kgdb.
Much thanks to Josh for help with the cleanups!
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/time.c')
| -rw-r--r-- | arch/x86/kernel/time.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c index 0e14f6c0d35e..2acbab329754 100644 --- a/arch/x86/kernel/time.c +++ b/arch/x86/kernel/time.c @@ -37,8 +37,7 @@ unsigned long profile_pc(struct pt_regs *regs) #ifdef CONFIG_FRAME_POINTER return *(unsigned long *)(regs->bp + sizeof(long)); #else - unsigned long *sp = - (unsigned long *)kernel_stack_pointer(regs); + unsigned long *sp = (unsigned long *)regs->sp; /* * Return address is either directly at stack pointer * or above a saved flags. Eflags has bits 22-31 zero, |