Hello, syzbot found the following issue on: HEAD commit: 7a396820222d Merge tag 'v6.8-rc-part2-smb-client' of git:/.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10c2406be80000 kernel config: https://syzkaller.appspot.com/x/.config?x=4059ab9bf06b6ceb dashboard link: https://syzkaller.appspot.com/bug?extid=2373f6be3e6de4f92562 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14669c6fe80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12d23ae3e80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/6bbe281de19f/disk-7a396820.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/aad457fc635f/vmlinux-7a396820.xz kernel image: https://storage.googleapis.com/syzbot-assets/b41601ff5beb/bzImage-7a396820.xz The issue was bisected to: commit 0d345996e4cb573f8cc81d49b3ee9a7fd2035bef Author: Pengfei Xu <pengfei.xu@xxxxxxxxx> Date: Mon Jul 31 03:04:18 2023 +0000 x86/kernel: increase kcov coverage under arch/x86/kernel folder bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1594cacfe80000 final oops: https://syzkaller.appspot.com/x/report.txt?x=1794cacfe80000 console output: https://syzkaller.appspot.com/x/log.txt?x=1394cacfe80000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2373f6be3e6de4f92562@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 0d345996e4cb ("x86/kernel: increase kcov coverage under arch/x86/kernel folder") INFO: task syz-executor208:5137 blocked for more than 143 seconds. Not tainted 6.7.0-syzkaller-12991-g7a396820222d #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor208 state:D stack:29312 pid:5137 tgid:5134 ppid:5112 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5400 [inline] __schedule+0xf12/0x5c00 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b9/0x9d0 kernel/locking/mutex.c:752 blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:406 sg_ioctl_common drivers/scsi/sg.c:1126 [inline] sg_ioctl+0x9ac/0x2760 drivers/scsi/sg.c:1160 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f61c0ac50d9 RSP: 002b:00007f61c0a60168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f61c0b4c3d8 RCX: 00007f61c0ac50d9 RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003 RBP: 00007f61c0b4c3d0 R08: 00007ffdb9ff9147 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f61c0b4c3dc R13: 000000000000006e R14: 00007ffdb9ff9060 R15: 00007ffdb9ff9148 </TASK> Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d1acba0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8d1acba0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8d1acba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by getty/4817: #0: ffff8880297d30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc6/0x1490 drivers/tty/n_tty.c:2201 3 locks held by syz-executor208/5136: 1 lock held by syz-executor208/5137: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:406 1 lock held by syz-executor208/5140: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:648 1 lock held by syz-executor208/5141: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:406 1 lock held by syz-executor208/5149: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:648 1 lock held by syz-executor208/5152: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:406 1 lock held by syz-executor208/5151: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:648 1 lock held by syz-executor208/5153: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:406 1 lock held by syz-executor208/5155: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_setup+0x33/0x60 kernel/trace/blktrace.c:648 1 lock held by syz-executor208/5156: #0: ffff88801e9032b0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_remove+0x1f/0x40 kernel/trace/blktrace.c:406 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.7.0-syzkaller-12991-g7a396820222d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 </TASK> Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5136 Comm: syz-executor208 Not tainted 6.7.0-syzkaller-12991-g7a396820222d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:write_comp_data+0x19/0x80 kernel/kcov.c:236 Code: 8b 80 f0 15 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 49 89 d2 49 89 f8 49 89 f1 65 48 8b 14 25 80 c2 03 00 65 8b 05 bf a6 7b 7e <a9> 00 01 ff 00 74 0f f6 c4 01 74 59 8b 82 fc 15 00 00 85 c0 74 4f RSP: 0018:ffffc900045e77e0 EFLAGS: 00000202 RAX: 0000000080000001 RBX: 0000000000000002 RCX: ffffffff813a4c8d RDX: ffff88806d973b80 RSI: 0000000000000003 RDI: 0000000000000001 RBP: ffffffff8ac9ccc0 R08: 0000000000000001 R09: 0000000000000003 R10: 0000000000000002 R11: 0000000000000002 R12: 0000000000000002 R13: 0000000000000001 R14: 0000000000000003 R15: 0000000000000002 FS: 00007f61c0a606c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e6254f9440 CR3: 000000006e15a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> __sanitizer_cov_trace_switch+0x54/0x90 kernel/kcov.c:341 unwind_next_frame+0x77d/0x2390 arch/x86/kernel/unwind_orc.c:581 __unwind_start+0x5a4/0x880 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xaf/0x170 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:129 __reset_page_owner+0x51/0x2e0 mm/page_owner.c:150 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x51f/0xb10 mm/page_alloc.c:2346 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2486 relay_destroy_buf+0x121/0x3e0 kernel/relay.c:201 relay_remove_buf kernel/relay.c:221 [inline] kref_put include/linux/kref.h:65 [inline] relay_close_buf+0x153/0x1b0 kernel/relay.c:430 relay_close kernel/relay.c:766 [inline] relay_close+0x3a8/0x5d0 kernel/relay.c:752 blk_trace_free+0x37/0x170 kernel/trace/blktrace.c:316 blk_trace_cleanup kernel/trace/blktrace.c:384 [inline] __blk_trace_remove+0x7f/0x130 kernel/trace/blktrace.c:397 blk_trace_remove+0x27/0x40 kernel/trace/blktrace.c:407 sg_ioctl_common drivers/scsi/sg.c:1126 [inline] sg_ioctl+0x9ac/0x2760 drivers/scsi/sg.c:1160 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f61c0ac50d9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f61c0a60168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f61c0b4c3d8 RCX: 00007f61c0ac50d9 RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003 RBP: 00007f61c0b4c3d0 R08: 00007ffdb9ff9147 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f61c0b4c3dc R13: 000000000000006e R14: 00007ffdb9ff9060 R15: 00007ffdb9ff9148 </TASK> INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.919 msecs --- 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. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
