Package: xvfb Version: 2:1.20.1-2 Severity: important X-Debbugs-Cc: debian-m...@lists.debian.org User: debian-m...@lists.debian.org Usertags: mips
My recent gtk+3.0 upload to experimental failed many of its build-time tests on mips. The tests could not connect to the Xvfb server run by the upstream build system, which later crashed with a segmentation fault. https://buildd.debian.org/status/fetch.php?pkg=gtk%2B3.0&arch=mips&ver=3.24.1-1&stamp=1537406479&file=log I can reproduce this reliably on the mips porterbox, minkus, by running Xvfb in a schroot with the options shown below. Core was generated by `Xvfb -ac -noreset -screen 0 1024x768x16 :1 -nolisten tcp -auth /dev/null'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x77a7c3f8 in ?? () from /usr/lib/mips-linux-gnu/libunwind.so.8 (gdb) bt #0 0x77a7c3f8 in ?? () from /usr/lib/mips-linux-gnu/libunwind.so.8 #1 0x77a7c99c in _ULmips_is_signal_frame () from /usr/lib/mips-linux-gnu/libunwind.so.8 #2 0x77a7cbb0 in _ULmips_handle_signal_frame () from /usr/lib/mips-linux-gnu/libunwind.so.8 #3 0x77a7d01c in _ULmips_step () from /usr/lib/mips-linux-gnu/libunwind.so.8 #4 0x55eaaff0 in xorg_backtrace () at ../../../../os/backtrace.c:72 #5 0x55eb0444 in OsSigHandler (signo=11, sip=0x7fd51fc8, unused=<optimized out>) at ../../../../os/osinit.c:135 #6 <signal handler called> #7 0x77a7c3f8 in ?? () from /usr/lib/mips-linux-gnu/libunwind.so.8 #8 0x77a7c99c in _ULmips_is_signal_frame () from /usr/lib/mips-linux-gnu/libunwind.so.8 #9 0x77a7cbb0 in _ULmips_handle_signal_frame () from /usr/lib/mips-linux-gnu/libunwind.so.8 #10 0x77a7d01c in _ULmips_step () from /usr/lib/mips-linux-gnu/libunwind.so.8 #11 0x77a7a8f8 in unw_backtrace () from /usr/lib/mips-linux-gnu/libunwind.so.8 #12 0x55eb06b0 in OsInit () at ../../../../os/osinit.c:217 #13 0x55e4d708 in dix_main (argc=11, argv=0x7fd639e4, envp=<optimized out>) at ../../../../dix/main.c:154 #14 0x7759ccf8 in __libc_start_main () from /lib/mips-linux-gnu/libc.so.6 #15 0x55d28e34 in __start () Backtrace stopped: frame did not save the PC Line 217 is this backtrace() call: #ifdef HAVE_BACKTRACE /* * initialize the backtracer, since the ctor calls dlopen(), which * calls malloc(), which isn't signal-safe. */ do { void *array; backtrace(&array, 1); <--- here } while (0); #endif so this might really be a libunwind bug (please reassign if you think so). libunwind8:mips 1.2.1-8 was installed. I thought this might be hardware-specific, but according to machines.cgi, mips-sil-01 (where gtk+3.0 failed) and mips-manda-01 (where a libepoxy build with the same xvfb and libunwind8 versions, also using Xvfb for tests, succeeded) are matching hardware, a Rhino Labs UTM8. minkus, the porterbox where I reproduced this, is apparently an EdgeRouter Pro. Xvfb is used in many packages' build-time tests, which for most maintainers are the only evidence we have that our packages are at all functional on mips, so it might be a good idea to work around this in Xvfb by disabling backtrace support and/or libunwind on mips. smcv
