Date: Mon, 09 Mar 2015 14:00:04 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-threads@FreeBSD.org Subject: [Bug 198452] libthr/rtld deadlock Message-ID: <bug-198452-16@https.bugs.freebsd.org/bugzilla/>
next in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=198452 Bug ID: 198452 Summary: libthr/rtld deadlock Product: Base System Version: 11.0-CURRENT Hardware: amd64 OS: Any Status: New Severity: Affects Only Me Priority: --- Component: threads Assignee: freebsd-threads@FreeBSD.org Reporter: dpejesh@yahoo.com I've run into what appears to be a deadlock with the following code when linked against libthr. Prior to base r245630 this worked as intended. Reverting base r245630 and base r249425 in HEAD appears to fix it. #include <dlfcn.h> #include <link.h> int32_t callback(struct dl_phdr_info *info, size_t size, void *data) { dlopen(info->dlpi_name, RTLD_LAZY); return 0; } int main() { dl_iterate_phdr(callback, 0); return 0; } When linked with libthr the program deadlocks on the call to dlopen(). clang -g -lthr -o main main.c The backtrace I'm seeing is: (gdb) bt #0 0x0000000800833ddc in _umtx_op_err () from /lib/libthr.so.3 #1 0x000000080082a29f in __thr_rwlock_wrlock (rwlock=0x800a42900, tsp=<optimized out>) at /usr/src/lib/libthr/thread/thr_umtx.c:296 #2 0x00000008008317f3 in _thr_rwlock_wrlock (rwlock=<optimized out>, tsp=<optimized out>) at /usr/src/lib/libthr/thread/thr_umtx.h:204 #3 _thr_rtld_wlock_acquire (lock=0x800a42900) at /usr/src/lib/libthr/thread/thr_rtld.c:141 #4 0x000000080060b5c2 in wlock_acquire (lock=0x80081f8a0 <rtld_locks>, lockstate=0x7fffffffe058) at /usr/src/libexec/rtld-elf/rtld_lock.c:213 #5 0x000000080060905f in dlopen_object () from /libexec/ld-elf.so.1 #6 0x00000008006060a3 in rtld_dlopen (name=0x7fffffffefcc "/root/deadlock/main", fd=-1, mode=<optimized out>) at /usr/src/libexec/rtld-elf/rtld.c:2955 #7 0x000000000040081f in callback (info=0x7fffffffeb08, size=64, data=0x0) at main.c:7 #8 0x0000000800606eeb in dl_iterate_phdr (callback=0x4007e0 <callback>, param=0x0) at /usr/src/libexec/rtld-elf/rtld.c:3416 #9 0x0000000000400858 in main () at main.c:12 -- You are receiving this mail because: You are the assignee for the bug.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-198452-16>