Hello, syzbot found the following issue on: HEAD commit: a41a877bc12d Merge branch 'for-next/fixes' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=13901aad080000 kernel config: https://syzkaller.appspot.com/x/.config?x=5cea15779c42821c dashboard link: https://syzkaller.appspot.com/bug?extid=8608bb4553edb8c78f41 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: arm64 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10d75e95080000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15440857080000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8608bb4553edb8c78f41@xxxxxxxxxxxxxxxxxxxxxxxxx BUG: Dentry 00000000133f9b6b{i=0,n=.reiserfs_priv} still in use (1) [unmount of squashfs loop0] ------------[ cut here ]------------ WARNING: CPU: 1 PID: 3045 at fs/dcache.c:1676 umount_check+0xc0/0xc8 fs/dcache.c:1667 Modules linked in: CPU: 1 PID: 3045 Comm: syz-executor425 Not tainted 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : umount_check+0xc0/0xc8 fs/dcache.c:1667 lr : umount_check+0xc0/0xc8 fs/dcache.c:1667 sp : ffff800012ac3bc0 x29: ffff800012ac3bc0 x28: ffff0000c7bb05f8 x27: ffff80000d4e1e20 x26: ffff0000c7bb04e0 x25: 0000000000000001 x24: ffff0000c7bb05f8 x23: ffff0000c7bb0090 x22: ffff0000c7b9d138 x21: ffff8000085edd40 x20: 0000000000000000 x19: ffff0000c7bb0000 x18: 00000000000000c0 x17: 657375206e69206c x16: ffff80000dbb8658 x15: ffff0000c378cf80 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c378cf80 x11: ff808000081c39dc x10: 0000000000000000 x9 : 3f5cf90385ca4900 x8 : 3f5cf90385ca4900 x7 : ffff800008197c8c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff0001fefddcd0 x1 : 0000000100000002 x0 : 0000000000000060 Call trace: umount_check+0xc0/0xc8 fs/dcache.c:1667 d_walk+0x13c/0x55c fs/dcache.c:1386 do_one_tree fs/dcache.c:1683 [inline] shrink_dcache_for_umount+0x60/0x140 fs/dcache.c:1699 generic_shutdown_super+0x30/0x190 fs/super.c:473 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xd4 fs/super.c:332 deactivate_super+0xb8/0xbc fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x208 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1d0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:625 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642 el0t_64_sync+0x18c/0x190 irq event stamp: 168478 hardirqs last enabled at (168477): [<ffff8000081c1c48>] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (168478): [<ffff80000bffe9cc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:395 softirqs last enabled at (168132): [<ffff80000801c1f4>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (168130): [<ffff80000801c1c0>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- BUG: Dentry 00000000133f9b6b{i=0,n=.reiserfs_priv} still in use (1) [unmount of squashfs loop0] ------------[ cut here ]------------ WARNING: CPU: 1 PID: 3045 at fs/dcache.c:1676 umount_check+0xc0/0xc8 fs/dcache.c:1667 Modules linked in: CPU: 1 PID: 3045 Comm: syz-executor425 Tainted: G W 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : umount_check+0xc0/0xc8 fs/dcache.c:1667 lr : umount_check+0xc0/0xc8 fs/dcache.c:1667 sp : ffff800012ac3bc0 x29: ffff800012ac3bc0 x28: ffff0000c7bb05f8 x27: ffff80000d4e1e20 x26: ffff0000c7bb04e0 x25: 0000000000000001 x24: ffff0000c7bb05f8 x23: ffff0000c7bb0090 x22: ffff0000c7b9d138 x21: ffff8000085edd40 x20: 0000000000000000 x19: ffff0000c7bb0000 x18: 00000000000000c0 x17: 657375206e69206c x16: ffff80000dbb8658 x15: ffff0000c378cf80 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c378cf80 x11: ff808000081c39dc x10: 0000000000000000 x9 : 3f5cf90385ca4900 x8 : 3f5cf90385ca4900 x7 : ffff800008197c8c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff0001fefddcd0 x1 : 0000000100000003 x0 : 0000000000000060 Call trace: umount_check+0xc0/0xc8 fs/dcache.c:1667 d_walk+0x13c/0x55c fs/dcache.c:1386 do_one_tree fs/dcache.c:1683 [inline] shrink_dcache_for_umount+0x60/0x140 fs/dcache.c:1699 generic_shutdown_super+0x30/0x190 fs/super.c:473 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xd4 fs/super.c:332 deactivate_super+0xb8/0xbc fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x208 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1d0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:625 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642 el0t_64_sync+0x18c/0x190 irq event stamp: 168928 hardirqs last enabled at (168927): [<ffff8000081c1c48>] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (168928): [<ffff80000bffe9cc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:395 softirqs last enabled at (168922): [<ffff8000080102e4>] _stext+0x2e4/0x37c softirqs last disabled at (168635): [<ffff800008104658>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] softirqs last disabled at (168635): [<ffff800008104658>] invoke_softirq+0x70/0xbc kernel/softirq.c:452 ---[ end trace 0000000000000000 ]--- VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds. Have a nice day... BUG: Dentry 000000005431b8af{i=0,n=.reiserfs_priv} still in use (1) [unmount of squashfs loop0] ------------[ cut here ]------------ WARNING: CPU: 0 PID: 3045 at fs/dcache.c:1676 umount_check+0xc0/0xc8 fs/dcache.c:1667 Modules linked in: CPU: 0 PID: 3045 Comm: syz-executor425 Tainted: G W 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : umount_check+0xc0/0xc8 fs/dcache.c:1667 lr : umount_check+0xc0/0xc8 fs/dcache.c:1667 sp : ffff800012ac3bc0 x29: ffff800012ac3bc0 x28: ffff0000c7b98250 x27: ffff80000d4e1e20 x26: ffff0000c7b98138 x25: 0000000000000001 x24: ffff0000c7b98250 x23: ffff0000cc849570 x22: ffff0000cc99d750 x21: ffff8000085edd40 x20: 0000000000000000 x19: ffff0000cc8494e0 x18: 0000000000000350 x17: 657375206e69206c x16: ffff80000dbb8658 x15: ffff0000c378cf80 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c378cf80 x11: ff808000081c39dc x10: 0000000000000000 x9 : 3f5cf90385ca4900 x8 : 3f5cf90385ca4900 x7 : ffff800008197c8c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff0001fefbecd0 x1 : 0000000100000002 x0 : 0000000000000060 Call trace: umount_check+0xc0/0xc8 fs/dcache.c:1667 d_walk+0x13c/0x55c fs/dcache.c:1386 do_one_tree fs/dcache.c:1683 [inline] shrink_dcache_for_umount+0x60/0x140 fs/dcache.c:1699 generic_shutdown_super+0x30/0x190 fs/super.c:473 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xd4 fs/super.c:332 deactivate_super+0xb8/0xbc fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x208 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1d0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:625 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642 el0t_64_sync+0x18c/0x190 irq event stamp: 257288 hardirqs last enabled at (257287): [<ffff8000081c1c48>] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (257288): [<ffff80000bffe9cc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:395 softirqs last enabled at (256910): [<ffff80000801c1f4>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (256908): [<ffff80000801c1c0>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds. Have a nice day... BUG: Dentry 000000005431b8af{i=0,n=.reiserfs_priv} still in use (1) [unmount of squashfs loop0] ------------[ cut here ]------------ WARNING: CPU: 1 PID: 3045 at fs/dcache.c:1676 umount_check+0xc0/0xc8 fs/dcache.c:1667 Modules linked in: CPU: 1 PID: 3045 Comm: syz-executor425 Tainted: G W 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : umount_check+0xc0/0xc8 fs/dcache.c:1667 lr : umount_check+0xc0/0xc8 fs/dcache.c:1667 sp : ffff800012ac3bc0 x29: ffff800012ac3bc0 x28: ffff0000c7b98250 x27: ffff80000d4e1e20 x26: ffff0000c7b98138 x25: 0000000000000001 x24: ffff0000c7b98250 x23: ffff0000cc849570 x22: ffff0000cc88d138 x21: ffff8000085edd40 x20: 0000000000000000 x19: ffff0000cc8494e0 x18: 00000000000002ea x17: 657375206e69206c x16: ffff80000dbb8658 x15: ffff0000c378cf80 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c378cf80 x11: ff808000081c39dc x10: 0000000000000000 x9 : 3f5cf90385ca4900 x8 : 3f5cf90385ca4900 x7 : ffff800008197c8c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff0001fefddcd0 x1 : 0000000100000002 x0 : 0000000000000060 Call trace: umount_check+0xc0/0xc8 fs/dcache.c:1667 d_walk+0x13c/0x55c fs/dcache.c:1386 do_one_tree fs/dcache.c:1683 [inline] shrink_dcache_for_umount+0x60/0x140 fs/dcache.c:1699 generic_shutdown_super+0x30/0x190 fs/super.c:473 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xd4 fs/super.c:332 deactivate_super+0xb8/0xbc fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x208 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1d0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:625 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642 el0t_64_sync+0x18c/0x190 irq event stamp: 283828 hardirqs last enabled at (283827): [<ffff8000081c1c48>] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (283828): [<ffff80000bffe9cc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:395 softirqs last enabled at (283438): [<ffff80000801c1f4>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (283436): [<ffff80000801c1c0>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds. Have a nice day... BUG: Dentry 000000005431b8af{i=0,n=.reiserfs_priv} still in use (1) [unmount of squashfs loop0] ------------[ cut here ]------------ WARNING: CPU: 1 PID: 3045 at fs/dcache.c:1676 umount_check+0xc0/0xc8 fs/dcache.c:1667 Modules linked in: CPU: 1 PID: 3045 Comm: syz-executor425 Tainted: G W 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : umount_check+0xc0/0xc8 fs/dcache.c:1667 lr : umount_check+0xc0/0xc8 fs/dcache.c:1667 sp : ffff800012ac3bc0 x29: ffff800012ac3bc0 x28: ffff0000c7b98250 x27: ffff80000d4e1e20 x26: ffff0000c7b98138 x25: 0000000000000001 x24: ffff0000c7b98250 x23: ffff0000cc849570 x22: ffff0000cc88dc30 x21: ffff8000085edd40 x20: 0000000000000000 x19: ffff0000cc8494e0 x18: 0000000000000109 x17: 657375206e69206c x16: ffff80000dbb8658 x15: ffff0000c378cf80 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c378cf80 x11: ff808000081c39dc x10: 0000000000000000 x9 : 3f5cf90385ca4900 x8 : 3f5cf90385ca4900 x7 : ffff800008197c8c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff0001fefddcd0 x1 : 0000000000000002 x0 : 0000000000000060 Call trace: umount_check+0xc0/0xc8 fs/dcache.c:1667 d_walk+0x13c/0x55c fs/dcache.c:1386 do_one_tree fs/dcache.c:1683 [inline] shrink_dcache_for_umount+0x60/0x140 fs/dcache.c:1699 generic_shutdown_super+0x30/0x190 fs/super.c:473 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xd4 fs/super.c:332 deactivate_super+0xb8/0xbc fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x208 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1d0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:625 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642 el0t_64_sync+0x18c/0x190 irq event stamp: 335826 hardirqs last enabled at (335825): [<ffff8000081c1c48>] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (335826): [<ffff80000bffe9cc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:395 softirqs last enabled at (335820): [<ffff8000080102e4>] _stext+0x2e4/0x37c softirqs last disabled at (335803): [<ffff800008104658>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] softirqs last disabled at (335803): [<ffff800008104658>] invoke_softirq+0x70/0xbc kernel/softirq.c:452 ---[ end trace 0000000000000000 ]--- VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds. Have a nice day... loop0: unable to read partition table loop0: partition table beyond EOD, truncated BUG: Dentry 00000000cd442007{i=0,n=.reiserfs_priv} still in use (1) [unmount of squashfs loop0] ------------[ cut here ]------------ WARNING: CPU: 1 PID: 3045 at fs/dcache.c:1676 umount_check+0xc0/0xc8 fs/dcache.c:1667 Modules linked in: CPU: 1 PID: 3045 Comm: syz-executor425 Tainted: G W 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : umount_check+0xc0/0xc8 fs/dcache.c:1667 lr : umount_check+0xc0/0xc8 fs/dcache.c:1667 sp : ffff800012ac3bc0 x29: ffff800012ac3bc0 x28: ffff0000cc88d5f8 x27: ffff80000d4e1e20 x26: ffff0000cc88d4e0 x25: 0000000000000001 x24: ffff0000cc88d5f8 x23: ffff0000cc88d438 x22: ffff0000ca0579c0 x21: ffff8000085edd40 x20: 0000000000000000 x19: ffff0000cc88d3a8 x18: 000000000000009d x17: 657375206e69206c x16: ffff80000dbb8658 x15: ffff0000c378cf80 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c378cf80 x11: ff808000081c39dc x10: 0000000000000000 x9 : 3f5cf90385ca4900 x8 : 3f5cf90385ca4900 x7 : ffff800008197c8c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff0001fefddcd0 x1 : 0000000100000002 x0 : 0000000000000060 Call trace: umount_check+0xc0/0xc8 fs/dcache.c:1667 d_walk+0x13c/0x55c fs/dcache.c:1386 do_one_tree fs/dcache.c:1683 [inline] shrink_dcache_for_umount+0x60/0x140 fs/dcache.c:1699 generic_shutdown_super+0x30/0x190 fs/super.c:473 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xd4 fs/super.c:332 deactivate_super+0xb8/0xbc fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x208 kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1d0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:625 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642 el0t_64_sync+0x18c/0x190 irq event stamp: 366714 hardirqs last enabled at (366713): [<ffff8000081c1c48>] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (366714): [<ffff80000bffe9cc>] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:395 softirqs last enabled at (366346): [<ffff80000801c1f4>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (366344): [<ffff80000801c1c0>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[ end trace 0000000000000000 ]--- VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds. Have a nice day... loop0: unable to read partition table loop0: partition table beyond EOD, truncated --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches
