bisecting cause commit starting from e49d033bddf5b565044e2abe4241353959bc9120 building syzkaller on 6a81331a1d4c744da9204d02ec88d558f7eea9c9 testing commit e49d033bddf5b565044e2abe4241353959bc9120 with gcc (GCC) 10.2.1 20210217 kernel signature: 10932bbbc052d4c5eaa99806ce942fd286d4d135ea5cbc01a02e2f852e122fe4 run #0: crashed: INFO: task hung in io_ring_exit_work run #1: crashed: INFO: task hung in io_ring_exit_work run #2: crashed: INFO: task hung in io_ring_exit_work run #3: crashed: INFO: task hung in io_ring_exit_work run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK reproducer seems to be flaky testing release v5.11 testing commit f40ddce88593482919761f74910f42f4b84c004b with gcc (GCC) 10.2.1 20210217 kernel signature: e99cd9f143ce9d9fcac692e506c1f42fd7bad007e669bcc2d658384620d3ab58 run #0: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "/tmp/syz-executor730100903" "root@10.128.1.5:./syz-executor730100903"]: exit status 1 Connection timed out during banner exchange Connection to 10.128.1.5 port 22 timed out lost connection run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK # git bisect start e49d033bddf5b565044e2abe4241353959bc9120 f40ddce88593482919761f74910f42f4b84c004b Bisecting: 6137 revisions left to test after this (roughly 13 steps) [d99676af540c2dc829999928fb81c58c80a1dce4] Merge tag 'drm-next-2021-02-19' of git://anongit.freedesktop.org/drm/drm testing commit d99676af540c2dc829999928fb81c58c80a1dce4 with gcc (GCC) 10.2.1 20210217 kernel signature: 5ad479128f117a1d38bc7ee59edcdb592a5fda3fb52cbc77b71fa4437ceb8a6d run #0: crashed: WARNING in kvm_wait run #1: crashed: WARNING in kvm_wait run #2: crashed: WARNING in kvm_wait run #3: crashed: WARNING in kvm_wait run #4: crashed: WARNING in kvm_wait run #5: crashed: WARNING in kvm_wait run #6: crashed: WARNING in kvm_wait run #7: crashed: WARNING in kvm_wait run #8: crashed: WARNING in kvm_wait run #9: crashed: WARNING in kvm_wait run #10: crashed: WARNING in kvm_wait run #11: crashed: WARNING in kvm_wait run #12: crashed: WARNING in kvm_wait run #13: crashed: WARNING in kvm_wait run #14: crashed: WARNING in kvm_wait run #15: OK run #16: OK run #17: OK run #18: boot failed: WARNING in kvm_wait run #19: boot failed: WARNING in kvm_wait # git bisect bad d99676af540c2dc829999928fb81c58c80a1dce4 Bisecting: 3717 revisions left to test after this (roughly 12 steps) [f9d58de23152f2c16f326d7e014cfa2933b00304] Merge tag 'affs-for-5.12-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux testing commit f9d58de23152f2c16f326d7e014cfa2933b00304 with gcc (GCC) 10.2.1 20210217 kernel signature: 0e15079a3ab74417003eea81f14abff1aea815e5e366ab0cff272ccab2f025d2 all runs: OK # git bisect good f9d58de23152f2c16f326d7e014cfa2933b00304 Bisecting: 1854 revisions left to test after this (roughly 11 steps) [de1617578849acab8e16c9ffdce39b91fb50639d] Merge tag 'media/v5.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media testing commit de1617578849acab8e16c9ffdce39b91fb50639d with gcc (GCC) 10.2.1 20210217 kernel signature: 7e28e05eb4da68a9f518c2e311ced71a9dc6276ac4662a3b4b036b603ea6bbcd run #0: crashed: WARNING in kvm_wait run #1: crashed: WARNING in kvm_wait run #2: crashed: WARNING in kvm_wait run #3: crashed: WARNING in kvm_wait run #4: crashed: WARNING in kvm_wait run #5: crashed: WARNING in kvm_wait run #6: crashed: WARNING in kvm_wait run #7: crashed: WARNING in kvm_wait run #8: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "/tmp/syz-executor032245463" "root@10.128.10.12:./syz-executor032245463"]: exit status 1 ssh: connect to host 10.128.10.12 port 22: Connection timed out lost connection run #9: crashed: WARNING in kvm_wait run #10: crashed: WARNING in kvm_wait run #11: crashed: WARNING in kvm_wait run #12: crashed: WARNING in kvm_wait run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK # git bisect bad de1617578849acab8e16c9ffdce39b91fb50639d Bisecting: 929 revisions left to test after this (roughly 10 steps) [4a037ad5d115b2cc79a5071a7854475f365476fa] Merge tag 'for-linus-5.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip testing commit 4a037ad5d115b2cc79a5071a7854475f365476fa with gcc (GCC) 10.2.1 20210217 kernel signature: 004ba018d015baabd4e7208e2297f7528a5d4a346a8f96386c9b2e5d310cecf1 run #0: crashed: WARNING in kvm_wait run #1: crashed: WARNING in kvm_wait run #2: crashed: WARNING in kvm_wait run #3: crashed: WARNING in kvm_wait run #4: crashed: WARNING in kvm_wait run #5: crashed: WARNING in kvm_wait run #6: crashed: WARNING in kvm_wait run #7: crashed: WARNING in kvm_wait run #8: crashed: WARNING in kvm_wait run #9: crashed: WARNING in kvm_wait run #10: crashed: WARNING in kvm_wait run #11: crashed: WARNING in kvm_wait run #12: crashed: WARNING in kvm_wait run #13: crashed: WARNING in kvm_wait run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: boot failed: WARNING in kvm_wait # git bisect bad 4a037ad5d115b2cc79a5071a7854475f365476fa Bisecting: 451 revisions left to test after this (roughly 9 steps) [582cd91f69de8e44857cb610ebca661dac8656b7] Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block testing commit 582cd91f69de8e44857cb610ebca661dac8656b7 with gcc (GCC) 10.2.1 20210217 kernel signature: 98a7c4f543254251b4d086d0bfa838a217fd1758106acf0ea8f5cb17b266d9ab all runs: OK # git bisect good 582cd91f69de8e44857cb610ebca661dac8656b7 Bisecting: 247 revisions left to test after this (roughly 8 steps) [3f6ec19f2d05d800bbc42d95dece433da7697864] Merge tag 'timers-core-2021-02-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip testing commit 3f6ec19f2d05d800bbc42d95dece433da7697864 with gcc (GCC) 10.2.1 20210217 kernel signature: d9614fad6721e2744d1d2770f3507629fe789ed04a0c63a63802af7053dd7748 all runs: OK # git bisect good 3f6ec19f2d05d800bbc42d95dece433da7697864 Bisecting: 125 revisions left to test after this (roughly 7 steps) [85e853c5ec8486117182baab10c98b321daa6d47] Merge branch 'for-mingo-rcu' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu testing commit 85e853c5ec8486117182baab10c98b321daa6d47 with gcc (GCC) 10.2.1 20210217 kernel signature: 7bb2e20bda296641b115400b91f5f7d4a40b610d89203492e82477b640bd46dd run #0: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "/tmp/syz-executor845492516" "root@10.128.10.11:./syz-executor845492516"]: exit status 1 Connection timed out during banner exchange Connection to 10.128.10.11 port 22 timed out lost connection run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK # git bisect good 85e853c5ec8486117182baab10c98b321daa6d47 Bisecting: 73 revisions left to test after this (roughly 6 steps) [c5e6fc08feb2b88dc5dac2f3c817e1c2a4cafda4] sched,x86: Allow !PREEMPT_DYNAMIC testing commit c5e6fc08feb2b88dc5dac2f3c817e1c2a4cafda4 with gcc (GCC) 10.2.1 20210217 kernel signature: 1d397b076fdaf75e4844e82e6b33e79d600dbd4869a469d9dca29f8b8229a7f0 run #0: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "/tmp/syz-executor439984569" "root@10.128.1.63:./syz-executor439984569"]: exit status 1 Connection timed out during banner exchange Connection to 10.128.1.63 port 22 timed out lost connection run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK # git bisect good c5e6fc08feb2b88dc5dac2f3c817e1c2a4cafda4 Bisecting: 33 revisions left to test after this (roughly 5 steps) [9eef02334505411667a7b51a8f349f8c6c4f3b66] Merge tag 'locking-core-2021-02-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip testing commit 9eef02334505411667a7b51a8f349f8c6c4f3b66 with gcc (GCC) 10.2.1 20210217 kernel signature: 946c21ddd5e21761c7bbe8f3f5f788bf15847c180f169c6fed8935dd9f699537 run #0: crashed: WARNING in kvm_wait run #1: crashed: WARNING in kvm_wait run #2: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "/tmp/syz-executor917889834" "root@10.128.1.121:./syz-executor917889834"]: exit status 1 Connection timed out during banner exchange Connection to 10.128.1.121 port 22 timed out lost connection run #3: crashed: WARNING in kvm_wait run #4: crashed: WARNING in kvm_wait run #5: crashed: WARNING in kvm_wait run #6: crashed: WARNING in kvm_wait run #7: crashed: WARNING in kvm_wait run #8: crashed: WARNING in kvm_wait run #9: crashed: WARNING in kvm_wait run #10: crashed: WARNING in kvm_wait run #11: crashed: WARNING in kvm_wait run #12: crashed: WARNING in kvm_wait run #13: crashed: WARNING in kvm_wait run #14: crashed: WARNING in kvm_wait run #15: crashed: WARNING in kvm_wait run #16: crashed: WARNING in kvm_wait run #17: OK run #18: OK run #19: boot failed: WARNING in kvm_wait # git bisect bad 9eef02334505411667a7b51a8f349f8c6c4f3b66 Bisecting: 19 revisions left to test after this (roughly 4 steps) [62137364e3e8afcc745846c5c67cacf943149073] Merge branch 'linus' into locking/core, to pick up upstream fixes testing commit 62137364e3e8afcc745846c5c67cacf943149073 with gcc (GCC) 10.2.1 20210217 kernel signature: dd66e5e6f419a6c0e47632da6e52772605bf95682fd106eabfa38602abf67e5a run #0: crashed: WARNING in kvm_wait run #1: crashed: WARNING in kvm_wait run #2: crashed: WARNING in kvm_wait run #3: crashed: WARNING in kvm_wait run #4: crashed: WARNING in kvm_wait run #5: crashed: WARNING in kvm_wait run #6: crashed: WARNING in kvm_wait run #7: crashed: WARNING in kvm_wait run #8: crashed: WARNING in kvm_wait run #9: crashed: WARNING in kvm_wait run #10: crashed: WARNING in kvm_wait run #11: crashed: WARNING in kvm_wait run #12: crashed: WARNING in kvm_wait run #13: crashed: WARNING in kvm_wait run #14: OK run #15: OK run #16: OK run #17: OK run #18: boot failed: WARNING in kvm_wait run #19: boot failed: WARNING in kvm_wait # git bisect bad 62137364e3e8afcc745846c5c67cacf943149073 Bisecting: 9 revisions left to test after this (roughly 3 steps) [997acaf6b4b59c6a9c259740312a69ea549cc684] lockdep: report broken irq restoration testing commit 997acaf6b4b59c6a9c259740312a69ea549cc684 with gcc (GCC) 10.2.1 20210217 kernel signature: 8ef728c50e58e18ab476595de69411c38a65aeb9076e859a67a7be5e88f6cf4f run #0: crashed: WARNING in kvm_wait run #1: crashed: WARNING in kvm_wait run #2: crashed: WARNING in kvm_wait run #3: crashed: WARNING in kvm_wait run #4: crashed: WARNING in kvm_wait run #5: crashed: WARNING in kvm_wait run #6: crashed: WARNING in kvm_wait run #7: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "/tmp/syz-executor599400291" "root@10.128.1.15:./syz-executor599400291"]: exit status 1 ssh: connect to host 10.128.1.15 port 22: Connection timed out lost connection run #8: crashed: WARNING in kvm_wait run #9: crashed: WARNING in kvm_wait run #10: crashed: WARNING in kvm_wait run #11: crashed: WARNING in kvm_wait run #12: crashed: WARNING in kvm_wait run #13: crashed: WARNING in kvm_wait run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: boot failed: WARNING in kvm_wait # git bisect bad 997acaf6b4b59c6a9c259740312a69ea549cc684 Bisecting: 4 revisions left to test after this (roughly 2 steps) [175b1a60e8805617d74aefe17ce0d3a32eceb55c] locking/lockdep: Clean up check_redundant() a bit testing commit 175b1a60e8805617d74aefe17ce0d3a32eceb55c with gcc (GCC) 10.2.1 20210217 kernel signature: 5bc32e5270ebcfa2da76f60758a0f1155c8c51bde2b7d64935ef0765cdbcf66a all runs: OK # git bisect good 175b1a60e8805617d74aefe17ce0d3a32eceb55c Bisecting: 2 revisions left to test after this (roughly 1 step) [7e923e6a3ceb877497dd9ee70d71fa33b94f332b] locking/selftests: Add local_lock inversion tests testing commit 7e923e6a3ceb877497dd9ee70d71fa33b94f332b with gcc (GCC) 10.2.1 20210217 kernel signature: 79e68a82e05d1c272b4ead924b35db0ce607c910a4d972eed30e02224f73c93a run #0: crashed: WARNING: ODEBUG bug in netdev_run_todo run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK run #10: OK run #11: OK run #12: OK run #13: OK run #14: OK run #15: OK run #16: OK run #17: OK run #18: OK run #19: OK # git bisect bad 7e923e6a3ceb877497dd9ee70d71fa33b94f332b Bisecting: 0 revisions left to test after this (roughly 0 steps) [5f2962401c6e195222f320d12b3a55377b2d4653] locking/lockdep: Exclude local_lock_t from IRQ inversions testing commit 5f2962401c6e195222f320d12b3a55377b2d4653 with gcc (GCC) 10.2.1 20210217 kernel signature: 79e68a82e05d1c272b4ead924b35db0ce607c910a4d972eed30e02224f73c93a all runs: OK # git bisect good 5f2962401c6e195222f320d12b3a55377b2d4653 7e923e6a3ceb877497dd9ee70d71fa33b94f332b is the first bad commit commit 7e923e6a3ceb877497dd9ee70d71fa33b94f332b Author: Peter Zijlstra Date: Wed Dec 9 16:06:06 2020 +0100 locking/selftests: Add local_lock inversion tests Test the local_lock_t inversion scenarios. Signed-off-by: Peter Zijlstra (Intel) lib/locking-selftest.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) culprit signature: 79e68a82e05d1c272b4ead924b35db0ce607c910a4d972eed30e02224f73c93a parent signature: 79e68a82e05d1c272b4ead924b35db0ce607c910a4d972eed30e02224f73c93a Reproducer flagged being flaky revisions tested: 16, total time: 4h33m21.574816212s (build: 1h46m47.827611754s, test: 2h44m7.21659322s) first bad commit: 7e923e6a3ceb877497dd9ee70d71fa33b94f332b locking/selftests: Add local_lock inversion tests recipients (to): ["linux-kernel@vger.kernel.org" "mingo@redhat.com" "peterz@infradead.org" "peterz@infradead.org" "will@kernel.org"] recipients (cc): [] crash: WARNING: ODEBUG bug in netdev_run_todo bond0 (unregistering): (slave bond_slave_0): Releasing backup interface bond0 (unregistering): Released all slaves ------------[ cut here ]------------ ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 kernel/workqueue.c:1601 WARNING: CPU: 0 PID: 23313 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Modules linked in: CPU: 0 PID: 23313 Comm: kworker/u4:43 Not tainted 5.11.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd 60 cc dd 88 4c 89 ee 48 c7 c7 60 c0 dd 88 e8 f7 74 7d 04 <0f> 0b 83 05 a5 98 bc 08 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffc90012cef888 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff88ddbc40 RDI: fffff5200259df03 RBP: 0000000000000001 R08: 0000000000000001 R09: ffff8880b9e30827 R10: ffffed10173c6104 R11: 0000000000000001 R12: ffffffff888cd280 R13: ffffffff88ddc6a0 R14: ffffffff81593cb0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000002273f000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:987 [inline] debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1018 slab_free_hook mm/slub.c:1539 [inline] slab_free_freelist_hook+0x107/0x150 mm/slub.c:1580 slab_free mm/slub.c:3142 [inline] kfree+0xdb/0x3b0 mm/slub.c:4124 device_release+0x93/0x200 drivers/base/core.c:1962 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x139/0x410 lib/kobject.c:753 netdev_run_todo+0x810/0xcd0 net/core/dev.c:10350 default_device_exit_batch+0x2ae/0x370 net/core/dev.c:11203 cleanup_net+0x423/0x990 net/core/net_namespace.c:604 process_one_work+0x84c/0x13b0 kernel/workqueue.c:2275 worker_thread+0x598/0xf80 kernel/workqueue.c:2421 kthread+0x36f/0x450 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296