Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/arch commit 544262583b0bd09ccd7d003ebe6dfe15e2f8cf5a Author: Peter Zijlstra <peterz(a)infradead.org&gt; AuthorDate: Mon Jul 13 12:55:58 2015 +0200 Commit: Peter Zijlstra <peterz(a)infradead.org&gt; CommitDate: Mon Jul 13 12:57:32 2015 +0200 atomic: Add simple atomic_t tests Add a few atomic_t tests, gets some compile coverage for the new operations. Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org&gt; +------------------------------------------+------------+------------+------------+ | | 12db72464b | 544262583b | 90ce597ebb | +------------------------------------------+------------+------------+------------+ | boot_successes | 67 | 0 | 0 | | boot_failures | 0 | 3 | 39 | | kernel_BUG_at_lib/atomic64_test.c | 0 | 3 | 39 | | invalid_opcode | 0 | 3 | 39 | | EIP_is_at_test_atomic64 | 0 | 3 | 39 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 3 | 39 | | backtrace:test_atomics | 0 | 3 | 39 | | backtrace:kernel_init_freeable | 0 | 3 | 39 | +------------------------------------------+------------+------------+------------+ [ 0.466903] devtmpfs: initialized [ 0.470773] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 6370867519511994 ns [ 0.473592] ------------[ cut here ]------------ [ 0.474838] kernel BUG at lib/atomic64_test.c:74! [ 0.476351] invalid opcode: 0000 [#1] DEBUG_PAGEALLOC [ 0.477813] Modules linked in: [ 0.478845] CPU: 0 PID: 1 Comm: swapper Not tainted 4.2.0-rc1-00061-g5442625 #121 [ 0.480944] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 0.483505] task: d08a0000 ti: d089c000 task.ti: d089c000 [ 0.484925] EIP: 0060:[<c19cecce>] EFLAGS: 00010286 CPU: 0 [ 0.486514] EIP is at test_atomic64+0x261/0x686 [ 0.487944] EAX: 00001001 EBX: c001d00d ECX: d089def0 EDX: aaa31337 [ 0.489647] ESI: d089def0 EDI: aaa31337 EBP: d089df08 ESP: d089def0 [ 0.491379] DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068 [ 0.492949] CR0: 8005003b CR2: ffffffff CR3: 01a37000 CR4: 000006f0 [ 0.494644] Stack: [ 0.495604] 00001001 aaa31337 d089df20 c19cf0f3 d08e5780 d089df1c d089df20 c19cf1c6 [ 0.498780] d1141ca0 00000000 c19cf1c6 20020110 d089df88 c1000522 c19af460 d089df70 [ 0.501960] c104753b 00000000 00000207 00000000 00010001 00000208 c191031c c19af460 [ 0.505024] Call Trace: [ 0.506019] [<c19cf0f3>] ? test_atomic64+0x686/0x686 [ 0.507298] [<c19cf1c6>] test_atomics+0xd3/0x104 [ 0.508260] [<c19cf1c6>] ? test_atomics+0xd3/0x104 [ 0.509242] [<c1000522>] do_one_initcall+0x178/0x18b [ 0.510247] [<c19af460>] ? do_early_param+0x73/0x73 [ 0.511239] [<c104753b>] ? parse_args+0x281/0x38b [ 0.512204] [<c19af460>] ? do_early_param+0x73/0x73 [ 0.513192] [<c1055cc6>] ? up_write+0x16/0x2a [ 0.514113] [<c19afc13>] kernel_init_freeable+0xf2/0x174 [ 0.515161] [<c19afc13>] ? kernel_init_freeable+0xf2/0x174 [ 0.516203] [<c15b61ef>] kernel_init+0x8/0xb0 [ 0.517134] [<c15bfce0>] ret_from_kernel_thread+0x20/0x30 [ 0.518184] [<c15b61e7>] ? rest_init+0x10e/0x10e [ 0.519140] Code: 37 13 a3 aa bb 0d d0 01 c0 e8 ef 2f 81 ff 81 65 e8 01 35 50 21 89 f1 e8 d1 2f 81 ff 81 fa 10 01 02 20 75 07 3d 01 10 00 00 74 02 <0f> 0b b9 37 13 a3 aa bb 0d d0 01 c0 e8 c1 2f 81 ff b8 22 22 22 [ 0.526381] EIP: [<c19cecce>] test_atomic64+0x261/0x686 SS:ESP 0068:d089def0 [ 0.527750] ---[ end trace ede0349e1a41d457 ]--- [ 0.528705] Kernel panic - not syncing: Fatal exception git bisect start 90ce597ebb6e92cc2d9695306fe141a45869464e abf9b5f800eb13e53543ff284177efb538dc68fd -- git bisect bad 469978279a282167615298f696da95ea7ca1be2e # 20:36 0- 3 Merge branch 'locking/core' git bisect bad f4b31f57ea4ac794e19499b0673b31f18a2cf342 # 20:48 0- 2 Merge branch 'locking/arch' git bisect good c3f6c60f34ac5ec3ae590c39d549774f3833b327 # 20:59 22+ 0 parisc: Provide atomic_{or,xor,and} git bisect good adc3b759a265a995243110d0e57a53c80f306725 # 21:07 22+ 0 frv: Rewrite atomic implementation git bisect good 41931052ec21f1a957257ba12fbcf457102f0259 # 21:16 22+ 0 atomic: Provide atomic_{or,xor,and} git bisect good 12db72464b0932998b35e5f15ac3a140fe969983 # 21:36 22+ 0 atomic: Replace atomic_{set,clear}_mask() usage git bisect bad 544262583b0bd09ccd7d003ebe6dfe15e2f8cf5a # 21:36 0- 2 atomic: Add simple atomic_t tests # first bad commit: [544262583b0bd09ccd7d003ebe6dfe15e2f8cf5a] atomic: Add simple atomic_t tests git bisect good 12db72464b0932998b35e5f15ac3a140fe969983 # 21:38 63+ 0 atomic: Replace atomic_{set,clear}_mask() usage # extra tests with DEBUG_INFO git bisect bad 544262583b0bd09ccd7d003ebe6dfe15e2f8cf5a # 21:48 0- 33 atomic: Add simple atomic_t tests # extra tests on HEAD of peterz-queue/master git bisect bad 90ce597ebb6e92cc2d9695306fe141a45869464e # 21:48 0- 17 Merge branch 'perf/core' # extra tests on tree/branch peterz-queue/locking/arch git bisect good d3b731eb1c8f4db32a3810b8c62d484b8e61b9f7 # 22:42 66+ 0 atomic: Add simple atomic_t tests # extra tests with first bad commit reverted git bisect good 1583b7d4aabce15a5c1a2f003fff78030d2a0cf5 # 23:11 66+ 2 Revert "atomic: Add simple atomic_t tests" # extra tests on tree/branch linus/master git bisect good bc0195aad0daa2ad5b0d76cce22b167bc3435590 # 00:12 66+ 9 Linux 4.2-rc2 # extra tests on tree/branch next/master git bisect good 2eb62d762a2112579f259903e62ba18d16c51f66 # 00:16 66+ 2 Add linux-next specific files for 20150713 This script may reproduce the error. ---------------------------------------------------------------------------- #!/bin/bash kernel=$1 kvm=( qemu-system-x86_64 -enable-kvm -cpu kvm64 -kernel $kernel -m 300 -smp 2 -device e1000,netdev=net0 -netdev user,id=net0 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -serial stdio -display none -monitor null ) append=( hung_task_panic=1 earlyprintk=ttyS0,115200 systemd.log_level=err debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw drbd.minor_count=8 ) "${kvm[@]}" --append "${append[*]}" ---------------------------------------------------------------------------- --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation