path: root/arch/x86/entry/entry_64.S
diff options
authorJosh Poimboeuf <jpoimboe@redhat.com>2018-05-18 08:47:12 +0200
committerIngo Molnar <mingo@kernel.org>2018-06-21 16:34:56 +0200
commitd31a580266eeb1f355df90fde8a71f480e30ad70 (patch)
treecd4bbc37279a4f72257c8338c4051a441239d570 /arch/x86/entry/entry_64.S
parent0c414367c04eeb00c3ebfee0b74c9e7f3b95fd62 (diff)
x86/unwind/orc: Detect the end of the stack
The existing UNWIND_HINT_EMPTY annotations happen to be good indicators of where entry code calls into C code for the first time. So also use them to mark the end of the stack for the ORC unwinder. Use that information to set unwind->error if the ORC unwinder doesn't unwind all the way to the end. This will be needed for enabling HAVE_RELIABLE_STACKTRACE for the ORC unwinder so we can use it with the livepatch consistency model. Thanks to Jiri Slaby for teaching the ORCs about the unwind hints. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> 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: https://lkml.kernel.org/lkml/20180518064713.26440-5-jslaby@suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/entry/entry_64.S')
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 73a522d53b53..c6f3677e6105 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -408,6 +408,7 @@ ENTRY(ret_from_fork)
/* kernel thread */
movq %r12, %rdi