forked from luck/tmp_suning_uos_patched
8a39e8c4d9
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:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.