rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=6b8c/1/0x4000000000000000 softirq=24750/24756 fqs=7 rcu: (detected by 0, t=10505 jiffies, g=21437, q=1072 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7975 Comm: syz.7.528 Not tainted 6.13.0-rc3-syzkaller-00193-ge9b8ffafd20a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:rcu_is_watching+0x0/0xb0 kernel/rcu/tree.c:733 Code: c7 60 d2 93 8e e8 70 a1 75 03 eb cd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 57 41 56 53 65 ff 05 e8 c6 7e 7e e8 7b a8 43 0a 89 RSP: 0018:ffffc90000a18d38 EFLAGS: 00000002 RAX: 0000000000010000 RBX: 0000000000000001 RCX: ffffffff818cda50 RDX: ffff8880307bbc00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000a18ea0 R08: ffffffff818cda76 R09: 1ffffffff2032fae R10: dffffc0000000000 R11: fffffbfff2032faf R12: 1ffff110170e593b R13: 0000000000000001 R14: ffff888012331340 R15: 0000000000000001 FS: 00007fb5d25f66c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa25e5a8fe4 CR3: 000000007f6c2000 CR4: 0000000000350ef0 Call Trace: trace_hrtimer_expire_exit include/trace/events/timer.h:306 [inline] __run_hrtimer kernel/time/hrtimer.c:1742 [inline] __hrtimer_run_queues+0x630/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0x996/0xeb0 Code: 48 21 c3 0f 85 16 02 00 00 e8 f6 ad 20 00 4c 8b 7c 24 10 4d 85 f6 75 07 e8 e7 ad 20 00 eb 06 e8 e0 ad 20 00 fb 48 8b 5c 24 18 <48> 8b 44 24 30 42 80 3c 28 00 74 08 48 89 df e8 a6 0e 87 00 4c 8b RSP: 0018:ffffc9000bb26d20 EFLAGS: 00000246 RAX: ffffffff817ec610 RBX: ffffffff8f175018 RCX: 0000000000080000 RDX: ffffc90004b19000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000bb26ed0 R08: ffffffff817ec5e7 R09: 1ffffffff2854910 R10: dffffc0000000000 R11: fffffbfff2854911 R12: ffffffff8f174fc0 R13: dffffc0000000000 R14: 0000000000000200 R15: ffffc9000bb26f20 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 _printk+0xd5/0x120 kernel/printk/printk.c:2457 set_capacity_and_notify+0x1ae/0x240 block/genhd.c:86 loop_set_size+0x44/0xb0 drivers/block/loop.c:232 loop_configure+0x9ec/0xeb0 drivers/block/loop.c:1101 lo_ioctl+0x846/0x1f50 blkdev_ioctl+0x57f/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf7/0x170 fs/ioctl.c:892 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: 0033:0x7fb5d478592b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fb5d25f5dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fb5d478592b RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000009756 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fb5d25f5ef0 R14: 00007fb5d25f5eb0 R15: 00007fb5ca000000 rcu: rcu_preempt kthread starved for 10470 jiffies! g21437 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:26264 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 8004 Comm: syz.4.539 Not tainted 6.13.0-rc3-syzkaller-00193-ge9b8ffafd20a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f8/0x2c60 kernel/smp.c:884 Code: 89 e6 83 e6 01 31 ff e8 56 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 e5 0b 00 eb 38 f3 90 42 0f b6 04 23 <84> c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 e4 0b 00 eb e4 44 RSP: 0018:ffffc9000bb17720 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff110170e88e9 RCX: 0000000000080000 RDX: ffffc9000d993000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000bb17908 R08: ffffffff81938eda R09: 1ffffffff2854925 R10: dffffc0000000000 R11: fffffbfff2854926 R12: dffffc0000000000 R13: ffff8880b8744748 R14: ffff8880b863fac0 R15: 0000000000000001 FS: 00007fd687ff96c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd687168800 CR3: 0000000028296000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 kill_bdev block/bdev.c:90 [inline] set_blocksize+0x2e2/0x360 block/bdev.c:173 sb_set_blocksize+0x47/0xf0 block/bdev.c:182 ext4_load_super fs/ext4/super.c:5107 [inline] __ext4_fill_super fs/ext4/super.c:5259 [inline] ext4_fill_super+0x12f0/0x6e60 fs/ext4/super.c:5733 get_tree_bdev_flags+0x48e/0x5c0 fs/super.c:1636 vfs_get_tree+0x92/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 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: 0033:0x7fd6871874ca Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd687ff8e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fd687ff8ef0 RCX: 00007fd6871874ca RDX: 0000000020000040 RSI: 0000000020000500 RDI: 00007fd687ff8eb0 RBP: 0000000020000040 R08: 00007fd687ff8ef0 R09: 0000000002000000 R10: 0000000002000000 R11: 0000000000000246 R12: 0000000020000500 R13: 00007fd687ff8eb0 R14: 00000000000004a6 R15: 000000000000002c watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz.4.539:8004] Modules linked in: irq event stamp: 960832 hardirqs last enabled at (960831): [] irqentry_exit+0x63/0x90 kernel/entry/common.c:357 hardirqs last disabled at (960832): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049 softirqs last enabled at (960826): [] __do_softirq kernel/softirq.c:595 [inline] softirqs last enabled at (960826): [] invoke_softirq kernel/softirq.c:435 [inline] softirqs last enabled at (960826): [] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 softirqs last disabled at (960779): [] __do_softirq kernel/softirq.c:595 [inline] softirqs last disabled at (960779): [] invoke_softirq kernel/softirq.c:435 [inline] softirqs last disabled at (960779): [] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 CPU: 0 UID: 0 PID: 8004 Comm: syz.4.539 Not tainted 6.13.0-rc3-syzkaller-00193-ge9b8ffafd20a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 56 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 01 e5 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 e5 e4 RSP: 0018:ffffc9000bb17720 EFLAGS: 00000246 RAX: ffffffff81938f0b RBX: 1ffff110170e88e9 RCX: 0000000000080000 RDX: ffffc9000d993000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000bb17908 R08: ffffffff81938eda R09: 1ffffffff2854925 R10: dffffc0000000000 R11: fffffbfff2854926 R12: dffffc0000000000 R13: ffff8880b8744748 R14: ffff8880b863fac0 R15: 0000000000000001 FS: 00007fd687ff96c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd687168800 CR3: 0000000028296000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 kill_bdev block/bdev.c:90 [inline] set_blocksize+0x2e2/0x360 block/bdev.c:173 sb_set_blocksize+0x47/0xf0 block/bdev.c:182 ext4_load_super fs/ext4/super.c:5107 [inline] __ext4_fill_super fs/ext4/super.c:5259 [inline] ext4_fill_super+0x12f0/0x6e60 fs/ext4/super.c:5733 get_tree_bdev_flags+0x48e/0x5c0 fs/super.c:1636 vfs_get_tree+0x92/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 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: 0033:0x7fd6871874ca Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd687ff8e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fd687ff8ef0 RCX: 00007fd6871874ca RDX: 0000000020000040 RSI: 0000000020000500 RDI: 00007fd687ff8eb0 RBP: 0000000020000040 R08: 00007fd687ff8ef0 R09: 0000000002000000 R10: 0000000002000000 R11: 0000000000000246 R12: 0000000020000500 R13: 00007fd687ff8eb0 R14: 00000000000004a6 R15: 000000000000002c Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7975 Comm: syz.7.528 Not tainted 6.13.0-rc3-syzkaller-00193-ge9b8ffafd20a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_preemption_disabled+0x27/0x120 lib/smp_processor_id.c:16 Code: 90 90 90 41 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 1d 1c 1e 3b 74 65 8b 05 11 1e 3b 74 ff ff ff 7f 74 26 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 0f RSP: 0018:ffffc90000a18c18 EFLAGS: 00000086 RAX: 0000000000010002 RBX: 0000000000000001 RCX: ffff8880307bbc00 RDX: ffff8880307bbc00 RSI: ffffffff8c5faec0 RDI: ffffffff8c5fae80 RBP: 0000000000000001 R08: ffffffff89cda602 R09: 1ffffffff2854910 R10: dffffc0000000000 R11: fffffbfff2854911 R12: dffffc0000000000 R13: ffff88807ed11c08 R14: ffff88807ed11c00 R15: ffff888012331360 FS: 00007fb5d25f66c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa25e5a8fe4 CR3: 000000007f6c2000 CR4: 0000000000350ef0 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:737 rcu_read_lock include/linux/rcupdate.h:850 [inline] advance_sched+0xa3b/0xca0 net/sched/sch_taprio.c:985 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x59d/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0x996/0xeb0 Code: 48 21 c3 0f 85 16 02 00 00 e8 f6 ad 20 00 4c 8b 7c 24 10 4d 85 f6 75 07 e8 e7 ad 20 00 eb 06 e8 e0 ad 20 00 fb 48 8b 5c 24 18 <48> 8b 44 24 30 42 80 3c 28 00 74 08 48 89 df e8 a6 0e 87 00 4c 8b RSP: 0018:ffffc9000bb26d20 EFLAGS: 00000246 RAX: ffffffff817ec610 RBX: ffffffff8f175018 RCX: 0000000000080000 RDX: ffffc90004b19000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc9000bb26ed0 R08: ffffffff817ec5e7 R09: 1ffffffff2854910 R10: dffffc0000000000 R11: fffffbfff2854911 R12: ffffffff8f174fc0 R13: dffffc0000000000 R14: 0000000000000200 R15: ffffc9000bb26f20 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 _printk+0xd5/0x120 kernel/printk/printk.c:2457 set_capacity_and_notify+0x1ae/0x240 block/genhd.c:86 loop_set_size+0x44/0xb0 drivers/block/loop.c:232 loop_configure+0x9ec/0xeb0 drivers/block/loop.c:1101 lo_ioctl+0x846/0x1f50 blkdev_ioctl+0x57f/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf7/0x170 fs/ioctl.c:892 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: 0033:0x7fb5d478592b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fb5d25f5dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fb5d478592b RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000009756 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fb5d25f5ef0 R14: 00007fb5d25f5eb0 R15: 00007fb5ca000000