[lkml]   [2020]   [Apr]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[tip: x86/urgent] objtool: Fix stack offset tracking for indirect CFAs
The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: d8dd25a461e4eec7190cb9d66616aceacc5110ad
Author: Josh Poimboeuf <>
AuthorDate: Sat, 25 Apr 2020 05:03:00 -05:00
Committer: Ingo Molnar <>
CommitterDate: Sat, 25 Apr 2020 12:22:27 +02:00

objtool: Fix stack offset tracking for indirect CFAs

When the current frame address (CFA) is stored on the stack (i.e.,
cfa->base == CFI_SP_INDIRECT), objtool neglects to adjust the stack
offset when there are subsequent pushes or pops. This results in bad
ORC data at the end of the ENTER_IRQ_STACK macro, when it puts the
previous stack pointer on the stack and does a subsequent push.

This fixes the following unwinder warning:

WARNING: can't dereference registers at 00000000f0a6bdba for ip interrupt_entry+0x9f/0xa0

Fixes: 627fce14809b ("objtool: Add ORC unwind table generation")
Reported-by: Vince Weaver <>
Reported-by: Dave Jones <>
Reported-by: Steven Rostedt <>
Reported-by: Vegard Nossum <>
Reported-by: Joe Mario <>
Reviewed-by: Miroslav Benes <>
Signed-off-by: Josh Poimboeuf <>
Signed-off-by: Ingo Molnar <>
Cc: Andy Lutomirski <>
Cc: Jann Horn <>
Cc: Peter Zijlstra <>
Cc: Thomas Gleixner <>
tools/objtool/check.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 4b170fd..e718464 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1449,7 +1449,7 @@ static int update_insn_state_regs(struct instruction *insn, struct insn_state *s
struct cfi_reg *cfa = &state->cfa;
struct stack_op *op = &insn->stack_op;

- if (cfa->base != CFI_SP)
+ if (cfa->base != CFI_SP && cfa->base != CFI_SP_INDIRECT)
return 0;

/* push */
 \ /
  Last update: 2020-04-26 08:49    [W:0.094 / U:1.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site