Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://github.com/fbq/linux.git per-ns-rename_lock commit 6155a1dcc08052d83f56edfe201e7c0b5b918dd4 Author: Boqun Feng <boqun.feng(a)gmail.com&gt; AuthorDate: Fri May 29 18:20:41 2015 +0800 Commit: Boqun Feng <boqun.feng(a)gmail.com&gt; CommitDate: Fri May 29 18:20:41 2015 +0800 vfs: use per-namespace rename_lock Signed-off-by: Boqun Feng <boqun.feng(a)gmail.com&gt; +------------------------------------------+------------+------------+------------+ | | b853a16176 | 6155a1dcc0 | 6155a1dcc0 | +------------------------------------------+------------+------------+------------+ | boot_successes | 60 | 0 | 0 | | boot_failures | 0 | 12 | 12 | | BUG:unable_to_handle_kernel | 0 | 12 | 12 | | Oops | 0 | 12 | 12 | | EIP_is_at_d_lookup | 0 | 12 | 12 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 12 | 12 | | backtrace:cryptomgr_test | 0 | 12 | 12 | +------------------------------------------+------------+------------+------------+ [ 7.313134] apm: BIOS version 1.2 Flags 0x03 (Driver version 1.16ac) [ 7.320482] apm: overridden by ACPI. [ 7.320482] apm: overridden by ACPI. [ 7.327879] BUG: unable to handle kernel [ 7.327879] BUG: unable to handle kernel NULL pointer dereferenceNULL pointer dereference at 0000000c at 0000000c [ 7.334886] IP: [ 7.334886] IP: [<c4b1d33b>] d_lookup+0x3a/0x130 [<c4b1d33b>] d_lookup+0x3a/0x130 [ 7.336214] *pdpt = 0000000000000000 [ 7.336214] *pdpt = 0000000000000000 *pde = f000ff53f000ff53 *pde = f000ff53f000ff53 [ 7.336214] Oops: 0000 [#1] [ 7.336214] Oops: 0000 [#1] [ 7.336214] CPU: 0 PID: 18 Comm: cryptomgr_test Not tainted 4.1.0-rc3-00132-g6155a1d #216 [ 7.336214] CPU: 0 PID: 18 Comm: cryptomgr_test Not tainted 4.1.0-rc3-00132-g6155a1d #216 [ 7.336214] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 7.336214] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 7.336214] task: cb5d7000 ti: d0734000 task.ti: d0734000 [ 7.336214] task: cb5d7000 ti: d0734000 task.ti: d0734000 [ 7.336214] EIP: 0060:[<c4b1d33b>] EFLAGS: 00010246 CPU: 0 [ 7.336214] EIP: 0060:[<c4b1d33b>] EFLAGS: 00010246 CPU: 0 [ 7.336214] EIP is at d_lookup+0x3a/0x130 [ 7.336214] EIP is at d_lookup+0x3a/0x130 [ 7.336214] EAX: 00000000 EBX: d0735e00 ECX: 00000000 EDX: 00000000 [ 7.336214] EAX: 00000000 EBX: d0735e00 ECX: 00000000 EDX: 00000000 [ 7.336214] ESI: d0735e7c EDI: cb5d7000 EBP: d0735e34 ESP: d0735e18 [ 7.336214] ESI: d0735e7c EDI: cb5d7000 EBP: d0735e34 ESP: d0735e18 [ 7.336214] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 [ 7.336214] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 [ 7.336214] CR0: 8005003b CR2: 0000000c CR3: 05b96000 CR4: 000006b0 [ 7.336214] CR0: 8005003b CR2: 0000000c CR3: 05b96000 CR4: 000006b0 [ 7.336214] Stack: [ 7.336214] Stack: [ 7.336214] cb5d7000 [ 7.336214] cb5d7000 d0735e7c d0735e7c c0102768 c0102768 00000002 00000002 d0735e8b d0735e8b d0735e7c d0735e7c c0102768 c0102768 d0735e4c d0735e4c [ 7.336214] c4b1d489 [ 7.336214] c4b1d489 d0735dd4 d0735dd4 d0735e8b d0735e8b c0102610 c0102610 00000012 00000012 d0735ea4 d0735ea4 c4b44ea3 c4b44ea3 d0735e8b d0735e8b [ 7.336214] 0000000d [ 7.336214] 0000000d c5745c73 c5745c73 00000012 00000012 00000000 00000000 cc7b4980 cc7b4980 cc7b4980 cc7b4980 cc7b499c cc7b499c 00000012 00000012 [ 7.336214] Call Trace: [ 7.336214] Call Trace: [ 7.336214] [<c4b1d489>] d_hash_and_lookup+0x58/0x5e [ 7.336214] [<c4b1d489>] d_hash_and_lookup+0x58/0x5e [ 7.336214] [<c4b44ea3>] proc_flush_task+0x85/0x151 [ 7.336214] [<c4b44ea3>] proc_flush_task+0x85/0x151 [ 7.336214] [<c4a43f9a>] release_task+0x5f/0x417 [ 7.336214] [<c4a43f9a>] release_task+0x5f/0x417 [ 7.336214] [<c4a67b03>] ? lock_release_holdtime+0xa9/0xb4 [ 7.336214] [<c4a67b03>] ? lock_release_holdtime+0xa9/0xb4 [ 7.336214] [<c4a45802>] ? do_exit+0x42c/0x91a [ 7.336214] [<c4a45802>] ? do_exit+0x42c/0x91a [ 7.336214] [<c4a6cb74>] ? do_raw_write_unlock+0x74/0x96 [ 7.336214] [<c4a6cb74>] ? do_raw_write_unlock+0x74/0x96 [ 7.336214] [<c4a45c07>] do_exit+0x831/0x91a [ 7.336214] [<c4a45c07>] do_exit+0x831/0x91a [ 7.336214] [<c4bea0e0>] ? cryptomgr_notify+0x370/0x370 [ 7.336214] [<c4bea0e0>] ? cryptomgr_notify+0x370/0x370 [ 7.336214] [<c4bea100>] cryptomgr_test+0x20/0x20 [ 7.336214] [<c4bea100>] cryptomgr_test+0x20/0x20 [ 7.336214] [<c4a598ee>] kthread+0xbe/0xc3 [ 7.336214] [<c4a598ee>] kthread+0xbe/0xc3 [ 7.336214] [<c4a6274b>] ? local_clock+0x12/0x1c [ 7.336214] [<c4a6274b>] ? local_clock+0x12/0x1c [ 7.336214] [<c4a664d3>] ? complete+0x17/0x3a [ 7.336214] [<c4a664d3>] ? complete+0x17/0x3a [ 7.336214] [<c5376380>] ret_from_kernel_thread+0x20/0x30 [ 7.336214] [<c5376380>] ret_from_kernel_thread+0x20/0x30 [ 7.336214] [<c4a59830>] ? __kthread_parkme+0x80/0x80 [ 7.336214] [<c4a59830>] ? __kthread_parkme+0x80/0x80 [ 7.336214] Code: [ 7.336214] Code: 3d 3d b0 b0 10 10 82 82 c5 c5 89 89 45 45 ec ec 89 89 55 55 e8 e8 a1 a1 b0 b0 10 10 82 82 c5 c5 89 89 45 45 e4 e4 8b 8b 45 45 e4 e4 83 83 3d 3d 94 94 5f 5f 82 82 c5 c5 00 00 8b 8b 80 80 38 38 03 03 00 00 00 00 0f 0f 94 94 c3 c3 31 31 c9 c9 0f 0f b6 b6 d3 d3 <8b> <8b> 70 70 0c 0c b8 b8 64 64 2a 2a a8 a8 c5 c5 e8 e8 9a 9a f4 f4 f8 f8 ff ff 84 84 db db 74 74 02 02 0f 0f 0b 0b 9c 9c 58 58 [ 7.336214] EIP: [<c4b1d33b>] [ 7.336214] EIP: [<c4b1d33b>] d_lookup+0x3a/0x130d_lookup+0x3a/0x130 SS:ESP 0068:d0735e18 SS:ESP 0068:d0735e18 [ 7.336214] CR2: 000000000000000c [ 7.336214] CR2: 000000000000000c [ 7.336214] ---[ end trace be9151c7869d7a03 ]--- [ 7.336214] ---[ end trace be9151c7869d7a03 ]--- git bisect start 6155a1dcc08052d83f56edfe201e7c0b5b918dd4 b853a16176cf3e02c57e215743015614152c2428 -- # first bad commit: [6155a1dcc08052d83f56edfe201e7c0b5b918dd4] vfs: use per-namespace rename_lock git bisect good b853a16176cf3e02c57e215743015614152c2428 # 19:58 60+ 0 turn user_{path_at,path,lpath,path_dir}() into static inlines # extra tests with DEBUG_INFO # extra tests on HEAD of fbq/per-ns-rename_lock git bisect bad 6155a1dcc08052d83f56edfe201e7c0b5b918dd4 # 20:02 0- 12 vfs: use per-namespace rename_lock # extra tests on tree/branch fbq/per-ns-rename_lock git bisect bad 6155a1dcc08052d83f56edfe201e7c0b5b918dd4 # 20:02 0- 12 vfs: use per-namespace rename_lock # extra tests with first bad commit reverted # extra tests on tree/branch linus/master git bisect good ace6a22a9fbcdba0ccf190f97b82a79ef2f44aeb # 20:09 60+ 0 Merge tag 'xtensa-20150526' of git://github.com/czankel/xtensa-linux # extra tests on tree/branch next/master git bisect good 5d925a7641c8066290ee58eaf4f651a1ea7d9c82 # 20:21 60+ 0 Add linux-next specific files for 20150528 This script may reproduce the error. ---------------------------------------------------------------------------- #!/bin/bash kernel=$1 initrd=quantal-core-i386.cgz wget --no-clobber https://github.com/fengguang/reproduce-kernel-bug/raw/master/initrd/$initrd kvm=( qemu-system-x86_64 -enable-kvm -cpu kvm64 -kernel $kernel -initrd $initrd -m 300 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -serial stdio -display none -monitor null ) append=( hung_task_panic=1 earlyprintk=ttyS0,115200 systemd.log_level=err debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw drbd.minor_count=8 ) "${kvm[@]}" --append "${append[*]}" ---------------------------------------------------------------------------- Thanks, Fengguang