Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master commit 4a9d4b024a3102fc083c925c242d98ac27b1c5f6 Author: Al Viro AuthorDate: Sun Jun 24 09:56:45 2012 +0400 Commit: Al Viro CommitDate: Sun Jul 22 23:57:58 2012 +0400 switch fput to task_work_add ... and schedule_work() for interrupt/kernel_thread callers (and yes, now it *is* OK to call from interrupt). We are guaranteed that __fput() will be done before we return to userland (or exit). Note that for fput() from a kernel thread we get an async behaviour; it's almost always OK, but sometimes you might need to have __fput() completed before you do anything else. There are two mechanisms for that - a general barrier (flush_delayed_fput()) and explicit __fput_sync(). Both should be used with care (as was the case for fput() from kernel threads all along). See comments in fs/file_table.c for details. Signed-off-by: Al Viro +-------------------------------------------------------+------------+------------+---------------+ | | a2d4c71d15 | 4a9d4b024a | next-20140725 | +-------------------------------------------------------+------------+------------+---------------+ | boot_successes | 900 | 189 | 14 | | boot_failures | 0 | 111 | 7 | | BUG:Bad_page_state_in_process | 0 | 1 | | | general_protection_fault | 0 | 2 | 2 | | RIP:slob_alloc | 0 | 1 | | | Kernel_panic-not_syncing:Fatal_exception | 0 | 15 | 6 | | backtrace:cryptomgr_test | 0 | 2 | 3 | | backtrace:kmem_cache_alloc_node | 0 | 1 | | | backtrace:__delayacct_tsk_init | 0 | 1 | | | backtrace:do_fork | 0 | 1 | | | BUG:kernel_boot_hang | 0 | 85 | | | BUG:spinlock_bad_magic_on_CPU | 0 | 2 | | | BUG:unable_to_handle_kernel_NULL_pointer_dereference | 0 | 3 | 1 | | Oops | 0 | 23 | 5 | | RIP:dcache_readdir | 0 | 1 | | | RIP:kobject_get_path | 0 | 1 | | | backtrace:acpi_bus_register_driver | 0 | 1 | | | backtrace:acpi_button_init | 0 | 1 | | | RIP:__d_lookup | 0 | 1 | | | BUG:unable_to_handle_kernel_paging_request | 0 | 20 | 6 | | RIP:slob_page_alloc | 0 | 8 | 2 | | backtrace:subsys_system_register | 0 | 9 | | | backtrace:init_clocksource_sysfs | 0 | 9 | | | RIP:kzfree | 0 | 10 | 2 | | Kernel_panic-not_syncing:Fatal_exception_in_interrupt | 0 | 10 | 1 | | backtrace:run_ksoftirqd | 0 | 10 | | | RIP:set_slob | 0 | 2 | | | RIP:do_raw_spin_lock | 0 | 1 | | | backtrace:async_schedule | 0 | 1 | | | backtrace:acpi_battery_init | 0 | 1 | | | RIP:__d_lookup_rcu | 0 | 0 | 1 | | backtrace:vfs_stat | 0 | 0 | 1 | | backtrace:SyS_newstat | 0 | 0 | 1 | | RIP:no_context | 0 | 0 | 1 | | RIP:crypto_ahash_setkey | 0 | 0 | 1 | +-------------------------------------------------------+------------+------------+---------------+ [ 0.491632] microcode: CPU0 sig=0x306c1, pf=0x1, revision=0x1 [ 0.492419] microcode: Microcode Update Driver: v2.00 , Peter Oruba [ 0.495181] alg: No test for __gcm-aes-aesni (__driver-gcm-aes-aesni) [ 0.496687] BUG: unable to handle kernel paging request at ffff8800122a0ad0 [ 0.496916] IP: [] slob_page_alloc+0x3c/0x1dc [ 0.496916] PGD 15a0063 PUD 15a4063 PMD 13cd5067 PTE 122a0160 [ 0.496916] Oops: 0000 [#1] DEBUG_PAGEALLOC [ 0.496916] CPU 0 [ 0.496916] Modules linked in: [ 0.496916] [ 0.496916] Pid: 1, comm: swapper Not tainted 3.5.0-rc6-00262-g4a9d4b0 #7 Bochs Bochs [ 0.496916] RIP: 0010:[] [] slob_page_alloc+0x3c/0x1dc [ 0.496916] RSP: 0018:ffff880012823bd8 EFLAGS: 00010002 [ 0.496916] RAX: ffff8800122a0ad0 RBX: ffff88001229df88 RCX: 0000000000000038 [ 0.496916] RDX: 0000000000000008 RSI: 0000000000000070 RDI: ffff88001229df88 [ 0.496916] RBP: ffff880012823c20 R08: ffff88001229dbc8 R09: ffffffff815c3410 [ 0.496916] R10: 0000000000000007 R11: 0000000000000008 R12: ffff8800132ce740 [ 0.496916] R13: 0000000000000000 R14: 0000000000000008 R15: ffff8800122a0ad0 [ 0.496916] FS: 0000000000000000(0000) GS:ffffffff815b0000(0000) knlGS:0000000000000000 [ 0.496916] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 0.496916] CR2: ffff8800122a0ad0 CR3: 000000000159f000 CR4: 00000000000406f0 [ 0.496916] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 0.496916] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 0.496916] Process swapper (pid: 1, threadinfo ffff880012822000, task ffff88001280e810) [ 0.496916] Stack: [ 0.496916] 0000000000000007 0000003800000008 fffffffffffffff8 0000000000000038 [ 0.496916] ffffffff815c3410 0000000000000070 ffff8800132ce740 0000000000000008 [ 0.496916] 0000000000000038 ffff880012823c80 ffffffff810b8c42 0000000000000297 [ 0.496916] Call Trace: [ 0.496916] [] slob_alloc.isra.15+0x8b/0x208 [ 0.496916] [] kmem_cache_alloc_node+0x28/0x5f [ 0.496916] [] ? kstrdup+0x28/0x41 [ 0.496916] [] sysfs_new_dirent+0x51/0x101 [ 0.496916] [] create_dir+0x33/0xa9 [ 0.496916] [] sysfs_create_dir+0x95/0xb3 [ 0.496916] [] kobject_add_internal+0xca/0x1c1 [ 0.496916] [] ? kobject_set_name+0x38/0x3a [ 0.496916] [] kset_register+0x20/0x3e [ 0.496916] [] kset_create_and_add+0x63/0x7d [ 0.496916] [] __bus_register+0x102/0x27b [ 0.496916] [] ? clocksource_done_booting+0x5a/0x5a [ 0.496916] [] subsys_system_register+0x1d/0xc1 [ 0.496916] [] ? clocksource_done_booting+0x5a/0x5a [ 0.496916] [] init_clocksource_sysfs+0x12/0x52 [ 0.496916] [] do_one_initcall+0x78/0x131 [ 0.496916] [] kernel_init+0x14a/0x1c2 [ 0.496916] [] ? do_early_param+0x8a/0x8a [ 0.496916] [] kernel_thread_helper+0x4/0x10 [ 0.496916] [] ? start_kernel+0x40a/0x40a [ 0.496916] [] ? gs_change+0x13/0x13 [ 0.496916] Code: 41 54 49 89 fc 53 31 db 48 83 ec 20 48 89 45 d0 48 d1 6d d0 48 63 c2 8b 4d d0 4c 8b 7f 20 4c 8d 50 ff 48 f7 d8 31 ff 48 89 45 c8 <66> 45 8b 37 b8 01 00 00 00 66 45 85 f6 44 0f 4e f0 85 d2 74 11 [ 0.496916] RIP [] slob_page_alloc+0x3c/0x1dc [ 0.496916] RSP [ 0.496916] CR2: ffff8800122a0ad0 [ 0.496916] ---[ end trace 4eaa2a86a8e2da22 ]--- [ 0.496916] Kernel panic - not syncing: Fatal exception git bisect start v3.6 v3.5 -- git bisect bad 1dd8372d350583b0acc8d7cfd7a1dee05e1942dc # 00:14 10- 12 MAINTAINERS: update address for Dan Williams git bisect bad a410963ba4c0c768302f0298e258b1ee940e8316 # 00:19 169- 7 Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux git bisect bad e8ff13b0bf88b5e696323a1eec877783d965b3c6 # 00:25 59- 24 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid git bisect bad e66d637134b7045ea6f14bdd416cd3695f73ed42 # 00:28 7- 13 Merge tag 'dma' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc git bisect good 7cd58b0a3b33ca9e1f1dd15b30c708ef77ba6d3e # 00:44 300+ 13 Merge tag 'regmap-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap git bisect bad a66d2c8f7ec1284206ca7c14569e2a607583f1e3 # 00:54 218- 7 Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs git bisect good 7100e505b76b4e2efd88b2459d1a932214e29f8a # 01:11 300+ 0 Merge tag 'pm-for-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm git bisect good 5b160bd426946c85f32b15e5d34d62d2618a5a87 # 01:19 300+ 0 Merge branch 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip git bisect good a6be1fcbc57f95bb47ef3c8e4ee3d83731b8f21e # 01:31 300+ 0 Merge tag 'mmc-merge-for-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc git bisect good 79714f72d3b964611997de512cb29198c9f2dbbb # 01:43 300+ 0 get rid of kern_path_parent() git bisect bad 715189d836ab276b3d0fc114681f12b423686ffa # 01:52 67- 2 hfs: push lock_super down git bisect good 0bdaea9017b9d2b9996e153a71ee03555969b80e # 02:12 300+ 1 VFS: Split inode_permission() git bisect bad 4a9d4b024a3102fc083c925c242d98ac27b1c5f6 # 02:20 43- 35 switch fput to task_work_add git bisect good 158e1645e07f3e9f7e4962d7a0997f5c3b98311b # 02:35 300+ 74 trim task_work: get rid of hlist git bisect good ed3e694d78cc75fa79bf29698631b146fd27aa35 # 02:47 300+ 0 move exit_task_work() past exit_files() et.al. git bisect good a2d4c71d1559426155e5da8db3265bfa0d8d398d # 02:57 300+ 0 deal with task_work callbacks adding more work # first bad commit: [4a9d4b024a3102fc083c925c242d98ac27b1c5f6] switch fput to task_work_add git bisect good a2d4c71d1559426155e5da8db3265bfa0d8d398d # 03:04 900+ 0 deal with task_work callbacks adding more work git bisect bad 5a7439efd1c5c416f768fc550048ca130cf4bf99 # 03:04 0- 7 Add linux-next specific files for 20140725 git bisect bad 9c5502189fa00ad623aed7ff006d5c2a16b121c0 # 03:11 12- 18 Merge tag 'sound-3.16-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound git bisect bad 5a7439efd1c5c416f768fc550048ca130cf4bf99 # 03:11 0- 7 Add linux-next specific files for 20140725 This script may reproduce the error. ---------------------------------------------------------------------------- #!/bin/bash kernel=$1 initrd=yocto-minimal-x86_64.cgz wget --no-clobber https://github.com/fengguang/reproduce-kernel-bug/blob/master/initrd/$initrd kvm=( qemu-system-x86_64 -enable-kvm -cpu Haswell,+smep,+smap -kernel $kernel -initrd $initrd -m 320 -smp 1 -net nic,vlan=1,model=e1000 -net user,vlan=1 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -serial stdio -display none -monitor null ) append=( hung_task_panic=1 earlyprintk=ttyS0,115200 debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=10 softlockup_panic=1 nmi_watchdog=panic prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal root=/dev/ram0 rw drbd.minor_count=8 ) "${kvm[@]}" --append "${append[*]}" ---------------------------------------------------------------------------- Thanks, Fengguang _______________________________________________ LKP mailing list LKP(a)linux.intel.com