uftrace
uftrace copied to clipboard
namhyung
t168_lib_nested.py gets segfault in i386 build
The test t168_lib_nested.py shows segfault in i386 build.
$ ./configure --arch=i386
$ make -j
$ cd tests
$ ./runtest.py -vdp -O0 168
Start 1 tests with 1 worker
Test case pg
------------------------: O0
build command for library: gcc -o libabc_test_lib.so -fno-inline -fno-builtin -fno-ipa-cp -fno-omit-frame-pointer -D_FORTIFY_SOURCE=0 -m32 -shared -fPIC s-lib.c
build command for library: g++ -o libfoo.so -fno-inline -fno-builtin -fno-ipa-cp -fno-omit-frame-pointer -D_FORTIFY_SOURCE=0 -m32 -shared -fPIC s-libfoo.cpp
build command for executable: gcc -o t-nest-libcall -fno-inline -fno-builtin -fno-ipa-cp -fno-omit-frame-pointer -D_FORTIFY_SOURCE=0 -m32 -pg -O0 s-nest-libcall.c -Wl,-rpath,$ORIGIN -L. -labc_test_lib -lfoo
test command: /home/honggyu/work/uftrace/uftrace live --no-pager --no-event --libmcount-path=/home/honggyu/work/uftrace -D3 --nest-libcall t-nest-libcall
[allocate_shmem_buffer:36] sess_id = /uftrace-3d792d1aa9a08b10-9593-000
WARN: child terminated by signal: 11: Segmentation fault
WARN: cannot open record data: /tmp/uftrace-live-URNYsx: No data available
168 lib_nested : SG
The segfault shows at this location.
27│ static struct mcount_shmem_buffer *allocate_shmem_buffer(char *sess_id, size_t size,
28│ int tid, int idx)
29│ {
30│ int fd;
31│ int saved_errno = 0;
32│ struct mcount_shmem_buffer *buffer = NULL;
33│
34│ snprintf(sess_id, size, SHMEM_SESSION_FMT, mcount_session_name(), tid, idx);
35│
36├───────> fd = shm_open(sess_id, O_RDWR | O_CREAT | O_TRUNC, 0600);
37│ if (fd < 0) {
38│ saved_errno = errno;
39│ pr_dbg("failed to open shmem buffer: %s\n", sess_id);
40│ goto out;
41│ }
The backtrace is here.
(gdb) bt
#0 0xf7d756ab in shm_open (name=0xffffc341 "uftrace-3fc09aaa37d78589-9778-000", oflag=578, mode=384) at ../sysdeps/posix/shm_open.c:36
#1 0xf7fa1542 in allocate_shmem_buffer (sess_id=sess_id@entry=0xffffc340 "/uftrace-3fc09aaa37d78589-9778-000", tid=tid@entry=9778, idx=idx@entry=0, size=128) at /home/honggyu/work/uftrace/libmcount/record.c:37
#2 0xf7fa1ec6 in prepare_shmem_buffer (mtdp=0xf7a096f0) at /home/honggyu/work/uftrace/libmcount/record.c:80
#3 0xf7f999ce in mcount_prepare () at /home/honggyu/work/uftrace/libmcount/mcount.c:790
#4 0xf7f9dec5 in __plthook_entry (regs=0xffffc4d4, module_id=4160739728, child_idx=4, ret_addr=0xffffc4ec) at /home/honggyu/work/uftrace/libmcount/plthook.c:781
#5 plthook_entry (ret_addr=0xffffc4ec, child_idx=32, module_id=4160739728, regs=0xffffc4d4) at /home/honggyu/work/uftrace/libmcount/plthook.c:935
#6 0xf7fb6f66 in plt_hooker () at /home/honggyu/work/uftrace/arch/i386/plthook.S:30
The same segfault shows in test 192 as well for the same problem in --nest-libcall.
168 lib_nested : SG SG SG SG SG SG SG SG SG SG
192 lib_name : SG SG SG SG SG SG SG SG SG SG
From a quick glance, I cannot find what's wrong. The session id seems valid...
