[ Upstream commit 8a39e8c4d9baf65d88f66d49ac684df381e30055 ]
When compiling with DEBUG=1 on Fedora 32 I'm getting crash for 'perf
test signal':
Program received signal SIGSEGV, Segmentation fault.
0x0000000000c68548 in __test_function ()
(gdb) bt
#0 0x0000000000c68548 in __test_function ()
#1 0x00000000004d62e9 in test_function () at tests/bp_signal.c:61
#2 0x00000000004d689a in test__bp_signal (test=0xa8e280 <generic_ ...
#3 0x00000000004b7d49 in run_test (test=0xa8e280 <generic_tests+1 ...
#4 0x00000000004b7e7f in test_and_print (t=0xa8e280 <generic_test ...
#5 0x00000000004b8927 in __cmd_test (argc=1, argv=0x7fffffffdce0, ...
...
It's caused by the symbol __test_function being in the ".bss" section:
$ readelf -a ./perf | less
[Nr] Name Type Address Offset
Size EntSize Flags Link Info Align
...
[28] .bss NOBITS 0000000000c356a0 008346a0
00000000000511f8 0000000000000000 WA 0 0 32
$ nm perf | grep __test_function
0000000000c68548 B __test_function
I guess most of the time we're just lucky the inline asm ended up in the
".text" section, so making it specific explicit with push and pop
section clauses.
$ readelf -a ./perf | less
[Nr] Name Type Address Offset
Size EntSize Flags Link Info Align
...
[13] .text PROGBITS 0000000000431240 00031240
0000000000306faa 0000000000000000 AX 0 0 16
$ nm perf | grep __test_function
00000000004d62c8 T __test_function
Committer testing:
$ readelf -wi ~/bin/perf | grep producer -m1
<c> DW_AT_producer : (indirect string, offset: 0x254a): GNU C99 10.2.1 20200723 (Red Hat 10.2.1-1) -mtune=generic -march=x86-64 -ggdb3 -std=gnu99 -fno-omit-frame-pointer -funwind-tables -fstack-protector-all
^^^^^
^^^^^
^^^^^
$
Before:
$ perf test signal
20: Breakpoint overflow signal handler : FAILED!
$
After:
$ perf test signal
20: Breakpoint overflow signal handler : Ok
$
Fixes: 8fd34e1cce ("perf test: Improve bp_signal")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lore.kernel.org/lkml/20200911130005.1842138-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
c5dbe21652