mirror of
https://github.com/torvalds/linux.git
synced 2024-12-12 06:02:38 +00:00
sched/x86: Fix thread_saved_pc()
thread_saved_pc() was using a completely bogus method to get the return address. Since switch_to() was previously inlined, there was no sane way to know where on the stack the return address was stored. Now with the frame of a sleeping thread well defined, this can be implemented correctly. Signed-off-by: Brian Gerst <brgerst@gmail.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1471106302-10159-7-git-send-email-brgerst@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
parent
616d24835e
commit
ffcb043ba5
@ -721,8 +721,6 @@ static inline void spin_lock_prefetch(const void *x)
|
||||
.addr_limit = KERNEL_DS, \
|
||||
}
|
||||
|
||||
extern unsigned long thread_saved_pc(struct task_struct *tsk);
|
||||
|
||||
/*
|
||||
* TOP_OF_KERNEL_STACK_PADDING reserves 8 bytes on top of the ring0 stack.
|
||||
* This is necessary to guarantee that the entire "struct pt_regs"
|
||||
@ -773,17 +771,13 @@ extern unsigned long thread_saved_pc(struct task_struct *tsk);
|
||||
.addr_limit = KERNEL_DS, \
|
||||
}
|
||||
|
||||
/*
|
||||
* Return saved PC of a blocked thread.
|
||||
* What is this good for? it will be always the scheduler or ret_from_fork.
|
||||
*/
|
||||
#define thread_saved_pc(t) READ_ONCE_NOCHECK(*(unsigned long *)((t)->thread.sp - 8))
|
||||
|
||||
#define task_pt_regs(tsk) ((struct pt_regs *)(tsk)->thread.sp0 - 1)
|
||||
extern unsigned long KSTK_ESP(struct task_struct *task);
|
||||
|
||||
#endif /* CONFIG_X86_64 */
|
||||
|
||||
extern unsigned long thread_saved_pc(struct task_struct *tsk);
|
||||
|
||||
extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
|
||||
unsigned long new_sp);
|
||||
|
||||
|
@ -513,6 +513,17 @@ unsigned long arch_randomize_brk(struct mm_struct *mm)
|
||||
return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
|
||||
}
|
||||
|
||||
/*
|
||||
* Return saved PC of a blocked thread.
|
||||
* What is this good for? it will be always the scheduler or ret_from_fork.
|
||||
*/
|
||||
unsigned long thread_saved_pc(struct task_struct *tsk)
|
||||
{
|
||||
struct inactive_task_frame *frame =
|
||||
(struct inactive_task_frame *) READ_ONCE(tsk->thread.sp);
|
||||
return READ_ONCE_NOCHECK(frame->ret_addr);
|
||||
}
|
||||
|
||||
/*
|
||||
* Called from fs/proc with a reference on @p to find the function
|
||||
* which called into schedule(). This needs to be done carefully
|
||||
|
@ -55,14 +55,6 @@
|
||||
#include <asm/switch_to.h>
|
||||
#include <asm/vm86.h>
|
||||
|
||||
/*
|
||||
* Return saved PC of a blocked thread.
|
||||
*/
|
||||
unsigned long thread_saved_pc(struct task_struct *tsk)
|
||||
{
|
||||
return ((unsigned long *)tsk->thread.sp)[3];
|
||||
}
|
||||
|
||||
void __show_regs(struct pt_regs *regs, int all)
|
||||
{
|
||||
unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
|
||||
|
Loading…
Reference in New Issue
Block a user