The following commit was bisected 2 times in a row to be the trigger(*) of the given back trace. The core dump happens at a 32 bit user mode linux image (stable Gentoo) fuzzy tested with trinity. It crashed often if 3 NFS shares heavily used by trinity were tried to be remounted. BAD commit Sun Sep 29 07:34:02 CEST 2013 ======================================================================= 275bb307865a316cef390e01e6ab5e21e97023a2 is the first bad commit commit 275bb307865a316cef390e01e6ab5e21e97023a2 Author: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> Date: Wed May 29 13:11:28 2013 -0400 NFSv4: Move dentry instantiation into the NFSv4-specific atomic open code Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> :040000 040000 075a18b71db9f50ad71f4637315f7f9c7cc19545 9bead78040810cb77ced8c134a8315e2e90eb237 M fs bisect run success back trace : tfoerste@n22 ~ $ cat /mnt/ramdisk/bt.v3.10-rc1-24-g275bb30 [New LWP 5953] [New LWP 5962] Core was generated by `/home/tfoerste/devel/linux/linux earlyprintk ubda=/home/tfoerste/virtual/uml/tr'. Program terminated with signal 6, Aborted. #0 0xb77dd424 in __kernel_vsyscall () #0 0xb77dd424 in __kernel_vsyscall () #1 0x0839bc45 in kill () #2 0x0807155d in uml_abort () at arch/um/os-Linux/util.c:93 #3 0x08071845 in os_dump_core () at arch/um/os-Linux/util.c:138 #4 0x08061197 in panic_exit (self=0x8599518 <panic_exit_notifier>, unused1=0, unused2=0x85ced60 <buf.12233>) at arch/um/kernel/um_arch.c:240 #5 0x0809dac8 in notifier_call_chain (nl=0x0, val=0, v=0x85ced60 <buf.12233>, nr_to_call=-2, nr_calls=0x0) at kernel/notifier.c:93 #6 0x0809dc13 in __atomic_notifier_call_chain (nr_calls=<optimized out>, nr_to_call=<optimized out>, v=<optimized out>, val=<optimized out>, nh=<optimized out>) at kernel/notifier.c:182 #7 atomic_notifier_call_chain (nh=0x85ced44 <panic_notifier_list>, val=0, v=0x85ced60 <buf.12233>) at kernel/notifier.c:191 #8 0x083f8fc8 in panic (fmt=0x0) at kernel/panic.c:127 #9 0x0810fee2 in shrink_dcache_for_umount_subtree (dentry=0x47bd7840) at fs/dcache.c:928 #10 0x08110628 in shrink_dcache_for_umount (sb=0x47eeef50) at fs/dcache.c:989 #11 0x080fed47 in generic_shutdown_super (sb=0x47eeef50) at fs/super.c:409 #12 0x080ffad5 in kill_anon_super (sb=0x0) at fs/super.c:880 #13 0x081cdea8 in nfs_kill_super (s=0x0) at fs/nfs/super.c:2563 #14 0x080fec0a in deactivate_locked_super (s=0x47eeef50) at fs/super.c:299 #15 0x080feca1 in deactivate_super (s=0x47eeef50) at fs/super.c:324 #16 0x0811686c in mntfree (mnt=<optimized out>) at fs/namespace.c:891 #17 mntput_no_expire (mnt=0x0) at fs/namespace.c:929 #18 0x08117d55 in SYSC_umount (flags=<optimized out>, name=<optimized out>) at fs/namespace.c:1335 #19 SyS_umount (name=134634000, flags=1) at fs/namespace.c:1305 #20 0x080616d2 in handle_syscall (r=0x4653f7d4) at arch/um/kernel/skas/syscall.c:35 #21 0x08073b1d in handle_trap (local_using_sysemu=<optimized out>, regs=<optimized out>, pid=<optimized out>) at arch/um/os-Linux/skas/process.c:198 #22 userspace (regs=0x4653f7d4) at arch/um/os-Linux/skas/process.c:431 #23 0x0805e44c in fork_handler () at arch/um/kernel/process.c:160 #24 0x00000000 in ?? () (*) due to the erratic nature of the issue the used test case is not 100% reproducible. Therefore although bisected 2 times in a row there's a chance that this commit is rather the upper limit instead of the 1st bad commit -- MfG/Sincerely Toralf Förster pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html