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authorWolfram Sang <wsa@kernel.org>2020-07-31 15:54:27 +0200
committerWolfram Sang <wsa@kernel.org>2020-07-31 15:54:27 +0200
commit073d398dc4841f62488ac6060ffeb9dfce6e0a98 (patch)
tree2ae9d508d0cd27f02584b9befb063dda5cb11a0b /arch/x86/kernel/unwind_orc.c
parentafca861bc6a3141c858d08279eb9afca76584fa6 (diff)
parent92ed301919932f777713b9172e525674157e983d (diff)
Merge tag 'v5.8-rc7' into i2c/for-5.9
Diffstat (limited to 'arch/x86/kernel/unwind_orc.c')
-rw-r--r--arch/x86/kernel/unwind_orc.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 7f969b2d240f..ec88bbe08a32 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -440,8 +440,11 @@ bool unwind_next_frame(struct unwind_state *state)
/*
* Find the orc_entry associated with the text address.
*
- * Decrement call return addresses by one so they work for sibling
- * calls and calls to noreturn functions.
+ * For a call frame (as opposed to a signal frame), state->ip points to
+ * the instruction after the call. That instruction's stack layout
+ * could be different from the call instruction's layout, for example
+ * if the call was to a noreturn function. So get the ORC data for the
+ * call instruction itself.
*/
orc = orc_find(state->signal ? state->ip : state->ip - 1);
if (!orc) {
@@ -662,6 +665,7 @@ void __unwind_start(struct unwind_state *state, struct task_struct *task,
state->sp = task->thread.sp;
state->bp = READ_ONCE_NOCHECK(frame->bp);
state->ip = READ_ONCE_NOCHECK(frame->ret_addr);
+ state->signal = (void *)state->ip == ret_from_fork;
}
if (get_stack_info((unsigned long *)state->sp, state->task,