66 lines
2.4 KiB
Diff
66 lines
2.4 KiB
Diff
|
From 93cd670426aaf4951bceb8f24f0ce63c24e16f5d Mon Sep 17 00:00:00 2001
|
||
|
|
From: Tao Liu <ltao@redhat.com>
|
||
|
|
Date: Wed, 16 Nov 2022 20:09:22 +0800
|
||
|
|
Subject: [PATCH 19/28] x86_64: Correct the identifier when locating the call
|
||
|
|
instruction
|
||
|
|
|
||
|
|
The previous implementation to locate the call instruction is
|
||
|
|
to strstr "call", then check whether the previous char is ' '
|
||
|
|
or '\t'. The implementation is problematic. For example it
|
||
|
|
cannot resolve the following disassembly string:
|
||
|
|
|
||
|
|
"0xffffffffc0995378 <nfs41_callback_svc+344>:\tcall 0xffffffff8ecfa4c0 <schedule>\n"
|
||
|
|
|
||
|
|
strstr will locate the "_call" and char check fails,
|
||
|
|
as a result, extract_hex fails to get the calling address.
|
||
|
|
|
||
|
|
NOTE: the issue is more likely to be reproduced when patch[1] applied.
|
||
|
|
Because without patch[1], the disassembly string will be as follows,
|
||
|
|
so the issue is no longer reproducible.
|
||
|
|
|
||
|
|
"0xffffffffc0995378:\tcall 0xffffffff8ecfa4c0 <schedule>\n"
|
||
|
|
|
||
|
|
Before the patch:
|
||
|
|
crash> bt 1472
|
||
|
|
PID: 1472 TASK: ffff8c121fa72f70 CPU: 18 COMMAND: "nfsv4.1-svc"
|
||
|
|
#0 [ffff8c16231a3db8] __schedule at ffffffff8ecf9ef3
|
||
|
|
#1 [ffff8c16231a3e40] schedule at ffffffff8ecfa4e9
|
||
|
|
|
||
|
|
After the patch:
|
||
|
|
crash> bt 1472
|
||
|
|
PID: 1472 TASK: ffff8c121fa72f70 CPU: 18 COMMAND: "nfsv4.1-svc"
|
||
|
|
#0 [ffff8c16231a3db8] __schedule at ffffffff8ecf9ef3
|
||
|
|
#1 [ffff8c16231a3e40] schedule at ffffffff8ecfa4e9
|
||
|
|
#2 [ffff8c16231a3e50] nfs41_callback_svc at ffffffffc099537d [nfsv4]
|
||
|
|
#3 [ffff8c16231a3ec8] kthread at ffffffff8e6b966f
|
||
|
|
#4 [ffff8c16231a3f50] ret_from_fork at ffffffff8ed07898
|
||
|
|
|
||
|
|
This patch fix the issue by strstr "\tcall" and " call", to
|
||
|
|
locate the correct call instruction.
|
||
|
|
|
||
|
|
[1]: https://listman.redhat.com/archives/crash-utility/2022-August/010085.html
|
||
|
|
|
||
|
|
Signed-off-by: Tao Liu <ltao@redhat.com>
|
||
|
|
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
|
||
|
|
---
|
||
|
|
x86_64.c | 3 +--
|
||
|
|
1 file changed, 1 insertion(+), 2 deletions(-)
|
||
|
|
|
||
|
|
diff --git a/x86_64.c b/x86_64.c
|
||
|
|
index b2a536e4b19c..292c240e887e 100644
|
||
|
|
--- a/x86_64.c
|
||
|
|
+++ b/x86_64.c
|
||
|
|
@@ -4429,8 +4429,7 @@ x86_64_function_called_by(ulong rip)
|
||
|
|
if (gdb_pass_through(buf, pc->tmpfile2, GNU_RETURN_ON_ERROR)) {
|
||
|
|
rewind(pc->tmpfile2);
|
||
|
|
while (fgets(buf, BUFSIZE, pc->tmpfile2)) {
|
||
|
|
- if ((p1 = strstr(buf, "callq")) &&
|
||
|
|
- whitespace(*(p1-1))) {
|
||
|
|
+ if ((p1 = strstr(buf, " callq")) || (p1 = strstr(buf, "\tcallq"))) {
|
||
|
|
if (extract_hex(p1, &value, NULLCHAR, TRUE))
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
--
|
||
|
|
2.37.1
|
||
|
|
|