INFO: task syz.3.689:8018 blocked for more than 143 seconds. Not tainted 6.11.0-rc1-syzkaller-00272-g17712b7ea075 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.689 state:D stack:25584 pid:8018 tgid:8011 ppid:5222 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __ww_mutex_lock+0xec2/0x2790 kernel/locking/mutex.c:759 ww_mutex_lock+0x40/0x1f0 kernel/locking/mutex.c:876 drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 drm_mode_getcrtc+0x152/0x770 drivers/gpu/drm/drm_crtc.c:544 drm_ioctl_kernel+0x33a/0x440 drivers/gpu/drm/drm_ioctl.c:745 drm_ioctl+0x611/0xad0 drivers/gpu/drm/drm_ioctl.c:842 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f292cf779f9 RSP: 002b:00007f292dd05048 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f292d106208 RCX: 00007f292cf779f9 RDX: 00000000200003c0 RSI: 00000000c06864a1 RDI: 0000000000000006 RBP: 00007f292cfe58ee R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f292d106208 R15: 00007ffe8ac76108 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e7377e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e7377e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7377e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6620 3 locks held by kworker/u8:6/1104: 2 locks held by getty/4969: #0: ffff88802b77b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 4 locks held by syz.2.556/7458: 1 lock held by syz.3.689/8018: #0: ffff8880204b10b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 1 lock held by syz.1.790/8405: #0: ffff8880204b10b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 5 locks held by syz.1.1054/9385: 1 lock held by syz.1.1054/9389: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc1-syzkaller-00272-g17712b7ea075 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 4660 Comm: klogd Not tainted 6.11.0-rc1-syzkaller-00272-g17712b7ea075 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:find_stack lib/stackdepot.c:553 [inline] RIP: 0010:stack_depot_save_flags+0x1ac/0x830 lib/stackdepot.c:618 Code: 4c 89 cd e8 e6 a5 c6 ff 49 89 e9 8b 6c 24 04 48 89 da 4c 8b 44 24 08 45 85 e4 75 68 4d 8b 3f 49 39 d7 74 5d 45 39 77 10 75 f2 <45> 39 4f 14 75 ec 31 c0 49 8b 0c c0 49 3b 4c c7 20 75 df 48 ff c0 RSP: 0018:ffffc900031c7470 EFLAGS: 00000246 RAX: ffff88823ac00000 RBX: 0000000000d98447 RCX: 0000000000368bc0 RDX: ffff88823af68bc0 RSI: 0000000000000003 RDI: 0000000055ff7eca RBP: 0000000000000001 R08: ffffc900031c74d0 R09: 000000000000000c R10: dffffc0000000000 R11: fffffbfff1fed02e R12: 00000000000000f0 R13: 000000000000000c R14: 00000000c6e368bc R15: ffff88802f3717b0 FS: 00007f9ad503a380(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000201f8000 CR3: 00000000296c6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x51/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:664 alloc_skb include/linux/skbuff.h:1320 [inline] alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6526 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815 unix_dgram_sendmsg+0x6d3/0x1f80 net/unix/af_unix.c:2030 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2212 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9ad519c9b5 Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fff89595f18 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f9ad519c9b5 RDX: 0000000000000050 RSI: 0000556314c49230 RDI: 0000000000000003 RBP: 0000556314c42910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007f9ad532a212 R14: 00007fff89596018 R15: 0000000000000000