[tip: core/kprobes] x86/alternatives: Update int3_emulate_push() comment

tip-bot2 for Peter Zijlstra
2019-11-15T09:43:49Z

The following commit has been merged into the core/kprobes branch of tip:

Commit-ID: 8959eb6ef5b86512452ef3bad167511dace61d84
Gitweb: https://git.kernel.org/tip/8959eb6ef5b86512452ef3bad167511dace61d84
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Tue, 03 Sep 2019 13:43:24 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Fri, 15 Nov 2019 09:07:41 +01:00

x86/alternatives: Update int3_emulate_push() comment

Update the comment now that we've merged x86_32 support.

Tested-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111132457.588386013@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/text-patching.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h
index 23c626a..ea91049 100644
--- a/arch/x86/include/asm/text-patching.h
+++ b/arch/x86/include/asm/text-patching.h
@@ -85,6 +85,9 @@ static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val)
* stack where the break point happened, and the saving of
* pt_regs. We can extend the original stack because of
* this gap. See the idtentry macro's create_gap option.
+ *
+ * Similarly entry_32.S will have a gap on the stack for (any) hardware
+ * exception and pt_regs; see FIXUP_FRAME.
*/
regs->sp -= sizeof(unsigned long);
*(unsigned long *)regs->sp = val;