Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master commit 29dee3c03abce04cd527878ef5f9e5f91b7b83f4 Author: Peter Zijlstra <peterz(a)infradead.org&gt; AuthorDate: Fri Feb 10 16:27:52 2017 +0100 Commit: Ingo Molnar <mingo(a)kernel.org&gt; CommitDate: Fri Feb 24 09:02:10 2017 +0100 locking/refcounts: Out-of-line everything Linus asked to please make this real C code. And since size then isn't an issue what so ever anymore, remove the debug knob and make all WARN()s unconditional. Suggested-by: Linus Torvalds <torvalds(a)linux-foundation.org&gt; Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org&gt; Cc: Peter Zijlstra <peterz(a)infradead.org&gt; Cc: Thomas Gleixner <tglx(a)linutronix.de&gt; Cc: dwindsor(a)gmail.com Cc: elena.reshetova(a)intel.com Cc: gregkh(a)linuxfoundation.org Cc: ishkamiel(a)gmail.com Cc: keescook(a)chromium.org Signed-off-by: Ingo Molnar <mingo(a)kernel.org&gt; 2bfe01eff4 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6 29dee3c03a locking/refcounts: Out-of-line everything +--------------------------------------------------+------------+------------+ | | 2bfe01eff4 | 29dee3c03a | +--------------------------------------------------+------------+------------+ | boot_successes | 7 | 0 | | boot_failures | 65 | 22 | | Kernel_panic-not_syncing:Fatal_exception | 65 | 21 | | WARNING:at_lib/kobject.c:#kobject_add_internal | 4 | 3 | | WARNING:at_lib/refcount.c:#refcount_inc | 0 | 19 | | WARNING:at_lib/refcount.c:#refcount_sub_and_test | 0 | 21 | +--------------------------------------------------+------------+------------+ [ 4.372151] sd 0:0:0:0: [sda] Write Protect is off [ 4.373531] sd 0:0:0:0: [sda] Mode Sense: 73 00 10 08 [ 4.434620] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA [ 4.447772] kobject (ffff88001c041f10): tried to init an initialized object, something is seriously wrong. [ 4.453395] CPU: 0 PID: 5 Comm: kworker/u2:0 Not tainted 4.10.0-01216-g29dee3c #2 [ 4.455534] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 4.458252] Workqueue: events_unbound async_run_entry_fn [ 4.459708] Call Trace: [ 4.460611] dump_stack+0x19/0x27 [ 4.461652] kobject_init+0xda/0xf0 [ 4.462731] blk_mq_register_dev+0x31/0x150 [ 4.463990] blk_register_queue+0x205/0x250 [ 4.465217] device_add_disk+0x1ab/0x710 [ 4.466384] sd_probe_async+0x11c/0x1e0 [ 4.467544] async_run_entry_fn+0xbd/0x220 [ 4.468760] process_one_work+0x4a7/0x990 [ 4.469938] ? process_one_work+0x348/0x990 [ 4.471168] worker_thread+0x342/0x8a0 [ 4.472300] ? process_one_work+0x990/0x990 [ 4.473540] kthread+0x188/0x190 [ 4.474557] ? kthread_create_on_node+0x40/0x40 [ 4.475850] ret_from_fork+0x31/0x40 [ 4.476978] kobject (ffff88001fcc02f0): tried to init an initialized object, something is seriously wrong. [ 4.479543] CPU: 0 PID: 5 Comm: kworker/u2:0 Not tainted 4.10.0-01216-g29dee3c #2 [ 4.481747] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 4.484356] Workqueue: events_unbound async_run_entry_fn [ 4.485755] Call Trace: [ 4.486580] dump_stack+0x19/0x27 [ 4.487585] kobject_init+0xda/0xf0 [ 4.488619] blk_mq_register_dev+0x4b/0x150 [ 4.489795] blk_register_queue+0x205/0x250 [ 4.490996] device_add_disk+0x1ab/0x710 [ 4.492123] sd_probe_async+0x11c/0x1e0 [ 4.493220] async_run_entry_fn+0xbd/0x220 [ 4.507429] process_one_work+0x4a7/0x990 [ 4.508581] ? process_one_work+0x348/0x990 [ 4.509752] worker_thread+0x342/0x8a0 [ 4.510852] ? process_one_work+0x990/0x990 [ 4.512038] kthread+0x188/0x190 [ 4.513009] ? kthread_create_on_node+0x40/0x40 [ 4.514283] ret_from_fork+0x31/0x40 [ 4.515422] ------------[ cut here ]------------ [ 4.516711] WARNING: CPU: 0 PID: 5 at lib/refcount.c:114 refcount_inc+0x65/0x70 [ 4.519092] refcount_t: increment on 0; use-after-free. [ 4.533534] Modules linked in: [ 4.534491] CPU: 0 PID: 5 Comm: kworker/u2:0 Not tainted 4.10.0-01216-g29dee3c #2 [ 4.536516] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 4.539115] Workqueue: events_unbound async_run_entry_fn [ 4.540523] Call Trace: [ 4.541349] dump_stack+0x19/0x27 [ 4.542347] __warn+0x150/0x170 [ 4.543312] warn_slowpath_fmt+0x4f/0x60 [ 4.544446] refcount_inc+0x65/0x70 [ 4.545486] kobject_get+0x4f/0x80 [ 4.559552] kobject_add_internal+0x6b/0x610 [ 4.560758] ? kfree_const+0x32/0x40 [ 4.561797] kobject_add_varg+0x45/0x60 [ 4.562897] kobject_add+0x77/0xa0 [ 4.563939] ? kobject_add+0x77/0xa0 [ 4.564986] blk_mq_register_hctx+0xc2/0xf0 [ 4.566170] blk_mq_register_dev+0xd8/0x150 [ 4.567362] blk_register_queue+0x205/0x250 [ 4.568526] device_add_disk+0x1ab/0x710 [ 4.569674] sd_probe_async+0x11c/0x1e0 [ 4.570849] async_run_entry_fn+0xbd/0x220 [ 4.572054] process_one_work+0x4a7/0x990 [ 4.573232] ? process_one_work+0x348/0x990 [ 4.574466] worker_thread+0x342/0x8a0 [ 4.575603] ? process_one_work+0x990/0x990 [ 4.576834] kthread+0x188/0x190 [ 4.577853] ? kthread_create_on_node+0x40/0x40 [ 4.579161] ret_from_fork+0x31/0x40 [ 4.580283] ---[ end trace 0433d9822ada324f ]--- [ 4.608948] sd 0:0:0:0: [sda] Attached SCSI disk git bisect start 0ac0099811fe1f36bf658b5f22f6cc3765c4563f c470abd4fde40ea6a0846a2beab642a578c0b8cd -- git bisect bad ea07c4bdbbbbf5ca77b3708123b3d1a9fb779c5d # 12:53 0- 2 Merge 'linux-platform-drivers-x86/testing' into devel-spot-201702260153 git bisect good c7db7d7086d06a6e7c4023c3e872b3a74191c96a # 02:09 24+ 26 Merge 'linux-review/Calin-Cruceru/ASoC-samsung-Remove-extra-blank-lines/20170225-201202' into devel-spot-201702260153 git bisect good cab29724c612cf5a5cf57fa00a420ef38836c17e # 02:27 24+ 25 Merge 'linux-review/Mihai-Burduselu/soc-blackfin-remove-out-of-memory-message/20170225-190702' into devel-spot-201702260153 git bisect good 94f0b014f854b8b4f80ce80e5fb2d15d5d8f337b # 15:38 24+ 25 Merge 'linux-review/Codrut-Grosu/ASoC-txx9-Added-requiered-spaces/20170225-181829' into devel-spot-201702260153 git bisect bad e46a787651fd8c9e24ce9a32f1a173b30682a73d # 15:57 0- 1 Merge 'tip/master' into devel-spot-201702260153 git bisect good 09c386ed86cb224159ccb9f738d1d6a5c73aafce # 16:59 23+ 23 Merge 'linux-review/Alexandru-Jercaianu/Staging-bcm2835-audio-Removed-redundant-check/20170225-182640' into devel-spot-201702260153 git bisect bad cc57e44c9e069da993cd18914e644983dc627188 # 17:18 0- 5 Merge branch 'locking/urgent' git bisect good 1db159781cc7df093085ccaddc022beaaa9dd990 # 17:36 22+ 25 Merge branch 'core/urgent' git bisect bad 318b1dedcd39012624f466d281627553e9fa2570 # 17:50 0- 9 locking/refcounts: Add missing kernel.h header to have UINT_MAX defined git bisect bad 29dee3c03abce04cd527878ef5f9e5f91b7b83f4 # 18:11 0- 5 locking/refcounts: Out-of-line everything # first bad commit: [29dee3c03abce04cd527878ef5f9e5f91b7b83f4] locking/refcounts: Out-of-line everything git bisect good 2bfe01eff4307409b95859e860261d0907149b61 # 18:53 67+ 65 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6 # extra tests with CONFIG_DEBUG_INFO_REDUCED git bisect bad 29dee3c03abce04cd527878ef5f9e5f91b7b83f4 # 19:23 0- 5 locking/refcounts: Out-of-line everything # extra tests on HEAD of linux-devel/devel-spot-201702260153 git bisect bad 0ac0099811fe1f36bf658b5f22f6cc3765c4563f # 19:23 0- 25 0day head guard for 'devel-spot-201702260153' # extra tests on tree/branch linux-next/master git bisect bad ed7b11e565c736828f0b793f596a4ca20efee747 # 19:40 0- 9 Add linux-next specific files for 20170227 # extra tests with first bad commit reverted git bisect good a7801a101e4d5c1e03c0ad46efb78fc8ab3e6779 # 22:12 66+ 62 Revert "locking/refcounts: Out-of-line everything" --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation