EXT4-fs (loop1): error count since last fsck: 1 ================================================================== BUG: KCSAN: data-race in _prb_read_valid / prb_reserve write to 0xffffffff86ccccd8 of 8 bytes by task 10196 on cpu 0: prb_reserve+0x73e/0xad0 kernel/printk/printk_ringbuffer.c:-1 vprintk_store+0x54a/0x910 kernel/printk/printk.c:2354 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 seq_buf_do_printk+0x113/0x1a0 lib/seq_buf.c:126 mem_cgroup_print_oom_meminfo+0x17d/0x260 mm/memcontrol.c:1829 dump_header+0xa2/0x240 mm/oom_kill.c:466 oom_kill_process+0x295/0x350 mm/oom_kill.c:1031 out_of_memory+0x97d/0xb80 mm/oom_kill.c:1169 mem_cgroup_out_of_memory mm/memcontrol.c:1907 [inline] mem_cgroup_oom mm/memcontrol.c:1930 [inline] try_charge_memcg+0x62f/0xa10 mm/memcontrol.c:2672 obj_cgroup_charge_pages mm/memcontrol.c:3072 [inline] __memcg_kmem_charge_page+0x1ce/0x3d0 mm/memcontrol.c:3116 __alloc_frozen_pages_noprof+0x18a/0x350 mm/page_alloc.c:5238 alloc_pages_mpol+0xb3/0x260 mm/mempolicy.c:2490 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline] alloc_pages_noprof+0x8f/0x140 mm/mempolicy.c:2581 vm_area_alloc_pages mm/vmalloc.c:3728 [inline] __vmalloc_area_node mm/vmalloc.c:3878 [inline] __vmalloc_node_range_noprof+0xaed/0x11c0 mm/vmalloc.c:4064 __kvmalloc_node_noprof+0x3d4/0x640 mm/slub.c:6861 futex_hash_allocate+0x190/0x9a0 kernel/futex/core.c:1815 futex_hash_prctl+0xd8/0xf0 kernel/futex/core.c:1961 __do_sys_prctl kernel/sys.c:2885 [inline] __se_sys_prctl+0x4f4/0x1400 kernel/sys.c:2534 __x64_sys_prctl+0x67/0x80 kernel/sys.c:2534 x64_sys_call+0x2533/0x3020 arch/x86/include/generated/asm/syscalls_64.h:158 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffffffff86ccccd8 of 8 bytes by interrupt on cpu 1: desc_read kernel/printk/printk_ringbuffer.c:500 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1934 [inline] prb_read kernel/printk/printk_ringbuffer.c:1982 [inline] _prb_read_valid+0x1be/0x950 kernel/printk/printk_ringbuffer.c:2173 desc_update_last_finalized+0x8f/0x170 kernel/printk/printk_ringbuffer.c:1573 prb_final_commit+0x111/0x150 kernel/printk/printk_ringbuffer.c:1842 vprintk_store+0x88b/0x910 kernel/printk/printk.c:2381 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 __ext4_msg+0x1aa/0x1c0 fs/ext4/super.c:1001 print_daily_error_info+0x7a/0x300 fs/ext4/super.c:3694 call_timer_fn+0x3b/0x240 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x415/0x5f0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0x31/0x70 kernel/time/timer.c:2405 handle_softirqs+0xb9/0x280 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 console_trylock_spinning kernel/printk/printk.c:-1 [inline] vprintk_emit+0x3d3/0x600 kernel/printk/printk.c:2478 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 __ext4_msg+0x1aa/0x1c0 fs/ext4/super.c:1001 ext4_handle_error+0x50a/0x550 fs/ext4/super.c:741 __ext4_error_inode+0x1bb/0x3c0 fs/ext4/super.c:871 ext4_free_branches+0x3ce/0x410 fs/ext4/indirect.c:1020 ext4_ind_truncate+0x782/0x840 fs/ext4/indirect.c:1201 ext4_truncate+0x66c/0xa10 fs/ext4/inode.c:4669 ext4_process_orphan+0x110/0x1c0 fs/ext4/orphan.c:337 ext4_orphan_cleanup+0x69c/0x9f0 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5701 [inline] ext4_fill_super+0x3408/0x37c0 fs/ext4/super.c:5824 get_tree_bdev_flags+0x291/0x300 fs/super.c:1694 get_tree_bdev+0x1f/0x30 fs/super.c:1717 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5856 vfs_get_tree+0x57/0x1d0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3758 [inline] do_new_mount+0x288/0x8d0 fs/namespace.c:3834 path_mount+0x4d0/0xbc0 fs/namespace.c:4154 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4360 __x64_sys_mount+0x67/0x80 fs/namespace.c:4360 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000000 -> 0x0000000000006a47 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 10233 Comm: syz.1.8603 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 ================================================================== EXT4-fs (loop1): initial error at time 2000000009: ext4_free_branches:1023: inode 16 EXT4-fs (loop1): last error at time 2000000009: ext4_free_branches:1023: inode 16 EXT4-fs (loop8): error count since last fsck: 1 EXT4-fs (loop8): initial error at time 2000000009: __ext4_get_inode_loc:4885 EXT4-fs (loop8): last error at time 2000000009: __ext4_get_inode_loc:4885