Here's a retest using pre2935. The strace comes out pretty much identical: # ensc_use_expensive_tests="no" ensc_test_debug="no" srctestsuitedir=./src/testsuite libinternaltestsuitedir=./lib_internal/testsuite strace lib_internal/testsuite/sigbus execve("lib_internal/testsuite/sigbus", ["lib_internal/testsuite/sigbus"], [/* 30 vars */]) = 0 open("/dev/urandom", O_RDONLY) = 3 read(3, "`\213\344\0", 4) = 4 open("/tmp/sigbus.0r29e0", O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW, 0600) = 4 close(3) = 0 open("/dev/urandom", O_RDONLY) = 3 read(3, "\3750\223\276", 4) = 4 open("/tmp/sigbus.t7c69v", O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW, 0600) = 5 close(3) = 0 write(4, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 73728) = 73728 close(4) = 0 close(5) = 0 unlink("/tmp/sigbus.t7c69v") = 0 stat64("/tmp/sigbus.0r29e0", {st_mode=S_IFREG|0600, st_size=73728, ...}) = 0 open("/tmp/sigbus.0r29e0", O_RDONLY|O_NOCTTY|O_NONBLOCK|O_LARGEFILE|O_NOFOLLOW) = 3 open("/tmp/sigbus.t7c69v", O_RDWR|O_CREAT|O_EXCL|O_NOCTTY|O_LARGEFILE, 0200) = 4 fstat64(3, {st_mode=S_IFREG|0600, st_size=73728, ...}) = 0 rt_sigaction(SIGBUS, {0x85f8, [BUS], SA_NODEFER}, {SIG_DFL, [], 0}, 8) = 0 _llseek(3, 0, [73728], SEEK_END) = 0 ftruncate64(4, 316659348799488) = 0 rt_sigprocmask(SIG_BLOCK, NULL, [], 8) = 0 mmap2(NULL, 73728, PROT_READ, MAP_SHARED, 3, 0) = 0x400d3000 mmap2(NULL, 73728, PROT_WRITE, MAP_SHARED, 4, 0) = 0x401e3000 madvise(0x400d3000, 73728, MADV_SEQUENTIAL) = 0 madvise(0x401e3000, 73728, MADV_SEQUENTIAL) = 0 munmap(0x401e3000, 73728) = 0 munmap(0x400d3000, 73728) = 0 rt_sigaction(SIGBUS, {SIG_DFL, [BUS], SA_NODEFER}, {0x85f8, [BUS], SA_NODEFER}, 8) = 0 close(4) = 0 close(3) = 0 socketpair(PF_FILE, SOCK_STREAM, 0, [3, 4]) = 0 rt_sigaction(SIGCHLD, {SIG_IGN, [CHLD], SA_NODEFER}, {SIG_DFL, [], 0}, 8) = 0 fork() = 12885 unlink("/tmp/sigbus.t7c69v") = 0 open("/tmp/sigbus.0r29e0", O_RDONLY|O_NOCTTY|O_NONBLOCK|O_LARGEFILE|O_NOFOLLOW) = 5 open("/tmp/sigbus.t7c69v", O_RDWR|O_CREAT|O_EXCL|O_NOCTTY|O_LARGEFILE, 0200) = 6 fstat64(5, {st_mode=S_IFREG|0600, st_size=73728, ...}) = 0 rt_sigaction(SIGBUS, {0x85f8, [BUS], SA_NODEFER}, {SIG_DFL, [BUS], SA_NODEFER}, 8) = 0 _llseek(5, 0, [73728], SEEK_END) = 0 ftruncate64(6, 316659348799488) = 0 rt_sigprocmask(SIG_BLOCK, NULL, [], 8) = 0 mmap2(NULL, 73728, PROT_READ, MAP_SHARED, 5, 0) = 0x40069000 mmap2(NULL, 73728, PROT_WRITE, MAP_SHARED, 6, 0) = 0x400b5000 madvise(0x40069000, 73728, MADV_SEQUENTIAL) = 0 madvise(0x400b5000, 73728, MADV_SEQUENTIAL) = 0 send(4, ".", 1, 0) = 1 recv(4, ".", 1, 0) = 1 --- SIGBUS (Bus error) @ 0 (0) --- munmap(0x400b5000, 73728) = 0 munmap(0x40069000, 73728) = 0 rt_sigaction(SIGBUS, {SIG_DFL, [BUS], SA_NODEFER}, {0x85f8, [BUS], SA_NODEFER}, 8) = 0 close(6) = 0 close(5) = 0 fork() = 12886 unlink("/tmp/sigbus.t7c69v") = 0 open("/tmp/sigbus.0r29e0", O_RDONLY|O_NOCTTY|O_NONBLOCK|O_LARGEFILE|O_NOFOLLOW) = 5 open("/tmp/sigbus.t7c69v", O_RDWR|O_CREAT|O_EXCL|O_NOCTTY|O_LARGEFILE, 0200) = 6 fstat64(5, {st_mode=S_IFREG|0600, st_size=36864, ...}) = 0 rt_sigaction(SIGBUS, {0x85f8, [BUS], SA_NODEFER}, {SIG_DFL, [BUS], SA_NODEFER}, 8) = 0 _llseek(5, 0, [36864], SEEK_END) = 0 ftruncate64(6, 158329674399744) = 0 rt_sigprocmask(SIG_BLOCK, NULL, [BUS], 8) = 0 mmap2(NULL, 36864, PROT_READ, MAP_SHARED, 5, 0) = 0x40089000 mmap2(NULL, 36864, PROT_WRITE, MAP_SHARED, 6, 0) = 0x400f3000 madvise(0x40089000, 36864, MADV_SEQUENTIAL) = 0 madvise(0x400f3000, 36864, MADV_SEQUENTIAL) = 0 send(4, ".", 1, 0) = 1 recv(4, ".", 1, 0) = 1 --- SIGBUS (Bus error) @ 0 (0) --- +++ killed by SIGBUS +++ Bus error The backtrace looks the same, too: # gdb --quiet sigbus core.14491 Reading symbols from /usr/src/redhat/BUILD/util-vserver-0.30.216-pre2935/lib_internal/testsuite/sigbus...done. [New Thread 14491] Core was generated by `lib_internal/testsuite/sigbus'. Program terminated with signal 7, Bus error. #0 copyMem (in_fd=0, out_fd=0) at lib_internal/testsuite/../unify-copy.c:95 95 if (*src != 0) *dst = *src; (gdb) backtrace #0 copyMem (in_fd=0, out_fd=0) at lib_internal/testsuite/../unify-copy.c:95 #1 copyMMap (in_fd=0, out_fd=0) at lib_internal/testsuite/../unify-copy.c:146 #2 0x00008578 in copyReg (src=<value optimized out>, src_stat=<value optimized out>, dst=<value optimized out>) at lib_internal/testsuite/../unify-copy.c:186 #3 0x000086e4 in checkTrunc (src=0xbeae1618 "/tmp/sigbus.oejsqt", dst=0xbeae1604 "/tmp/sigbus.p1dovd", st=0xbeae1598, pos=9029) at lib_internal/testsuite/sigbus.c:76 #4 0x0000886c in main () at lib_internal/testsuite/sigbus.c:105 Looking at where the the *src and *dst come from in #0, it seems they are mmap-ed and madvised in in unify-copy.c:copyMMap() So I'm guessing that it could be related to a bug in one of those libc functions. Does anyone agree/disagree on this? Gordan