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Diffstat (limited to 'arch/x86/include/asm/switch_to.h')
-rw-r--r--arch/x86/include/asm/switch_to.h23
1 files changed, 0 insertions, 23 deletions
diff --git a/arch/x86/include/asm/switch_to.h b/arch/x86/include/asm/switch_to.h
index 0e059b73437b..9f69cc497f4b 100644
--- a/arch/x86/include/asm/switch_to.h
+++ b/arch/x86/include/asm/switch_to.h
@@ -12,27 +12,6 @@ struct task_struct *__switch_to_asm(struct task_struct *prev,
__visible struct task_struct *__switch_to(struct task_struct *prev,
struct task_struct *next);
-/* This runs runs on the previous thread's stack. */
-static inline void prepare_switch_to(struct task_struct *next)
-{
-#ifdef CONFIG_VMAP_STACK
- /*
- * If we switch to a stack that has a top-level paging entry
- * that is not present in the current mm, the resulting #PF will
- * will be promoted to a double-fault and we'll panic. Probe
- * the new stack now so that vmalloc_fault can fix up the page
- * tables if needed. This can only happen if we use a stack
- * in vmap space.
- *
- * We assume that the stack is aligned so that it never spans
- * more than one top-level paging entry.
- *
- * To minimize cache pollution, just follow the stack pointer.
- */
- READ_ONCE(*(unsigned char *)next->thread.sp);
-#endif
-}
-
asmlinkage void ret_from_fork(void);
/*
@@ -67,8 +46,6 @@ struct fork_frame {
#define switch_to(prev, next, last) \
do { \
- prepare_switch_to(next); \
- \
((last) = __switch_to_asm((prev), (next))); \
} while (0)