__dump_stack+0x1d/0x30 lib/dump_stack.c:94 dump_stack_lvl+0xe8/0x140 lib/dump_stack.c:120 dump_stack+0x15/0x1b lib/dump_stack.c:129 fail_dump lib/fault-inject.c:73 [inline] should_fail_ex+0x265/0x280 lib/fault-inject.c:174 should_fail_alloc_page+0xf2/0x100 mm/fail_page_alloc.c:44 ================================================================== BUG: KCSAN: data-race in data_alloc / prb_reserve write to 0xffffffff86887990 of 8 bytes by task 37 on cpu 0: data_alloc+0x27d/0x2b0 kernel/printk/printk_ringbuffer.c:1096 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2475 __ext4_error+0x248/0x320 fs/ext4/super.c:813 ext4_release_dquot+0x2e7/0x460 fs/ext4/super.c:6967 quota_release_workfn+0x256/0x530 fs/quota/dquot.c:840 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3321 worker_thread+0x582/0x770 kernel/workqueue.c:3402 kthread+0x489/0x510 kernel/kthread.c:464 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read to 0xffffffff86887990 of 8 bytes by task 21465 on cpu 1: desc_read kernel/printk/printk_ringbuffer.c:482 [inline] desc_push_tail kernel/printk/printk_ringbuffer.c:778 [inline] desc_reserve kernel/printk/printk_ringbuffer.c:924 [inline] prb_reserve+0x221/0xaf0 kernel/printk/printk_ringbuffer.c:1619 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426 vprintk_default+0x26/0x30 kernel/printk/printk.c:2465 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2475 printk_stack_address arch/x86/kernel/dumpstack.c:70 [inline] show_trace_log_lvl+0x4e3/0x560 arch/x86/kernel/dumpstack.c:282 __dump_stack+0x1d/0x30 lib/dump_stack.c:94 dump_stack_lvl+0xe8/0x140 lib/dump_stack.c:120 dump_stack+0x15/0x1b lib/dump_stack.c:129 fail_dump lib/fault-inject.c:73 [inline] should_fail_ex+0x265/0x280 lib/fault-inject.c:174 should_fail_alloc_page+0xf2/0x100 mm/fail_page_alloc.c:44 prepare_alloc_pages mm/page_alloc.c:4745 [inline] __alloc_frozen_pages_noprof+0xff/0x360 mm/page_alloc.c:4959 alloc_pages_mpol+0xb3/0x250 mm/mempolicy.c:2301 folio_alloc_mpol_noprof mm/mempolicy.c:2320 [inline] vma_alloc_folio_noprof+0x1aa/0x300 mm/mempolicy.c:2355 folio_prealloc mm/memory.c:-1 [inline] alloc_anon_folio mm/memory.c:4943 [inline] do_anonymous_page mm/memory.c:5000 [inline] do_pte_missing mm/memory.c:4158 [inline] handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault mm/memory.c:6140 [inline] handle_mm_fault+0xe9f/0x2c00 mm/memory.c:6309 do_user_addr_fault+0x636/0x1090 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 value changed: 0x0000000000026c38 -> 0x00000000000e3b68 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 21465 Comm: syz.2.5710 Not tainted 6.15.0-syzkaller-10402-g4cb6c8af8591 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ================================================================== prepare_alloc_pages mm/page_alloc.c:4745 [inline] __alloc_frozen_pages_noprof+0xff/0x360 mm/page_alloc.c:4959 alloc_pages_mpol+0xb3/0x250 mm/mempolicy.c:2301 folio_alloc_mpol_noprof mm/mempolicy.c:2320 [inline] vma_alloc_folio_noprof+0x1aa/0x300 mm/mempolicy.c:2355 folio_prealloc mm/memory.c:-1 [inline] alloc_anon_folio mm/memory.c:4943 [inline] do_anonymous_page mm/memory.c:5000 [inline] do_pte_missing mm/memory.c:4158 [inline] handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault mm/memory.c:6140 [inline] handle_mm_fault+0xe9f/0x2c00 mm/memory.c:6309 do_user_addr_fault+0x636/0x1090 arch/x86/mm/fault.c:1336 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f6d9e66bf6b Code: c0 8b 87 c0 00 00 00 66 0f 6c c0 85 c0 0f 85 44 01 00 00 c7 87 c0 00 00 00 ff ff ff ff 48 8d 84 24 20 21 00 00 48 8d 7c 24 20 <0f> 29 44 24 40 49 89 e4 48 89 44 24 50 8b 43 74 48 89 9c 24 00 01 RSP: 002b:00007f6d9cd24e10 EFLAGS: 00010246 RAX: 00007f6d9cd26f30 RBX: 00007f6d9e8b3620 RCX: 0000000000000000 RDX: 00007f6d9cd26f78 RSI: 00007f6d9e71dbf8 RDI: 00007f6d9cd24e30 RBP: 0000000000000009 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 00007f6d9e8e5fa0 R15: 00007ffcb4cf6f68 Huh VM_FAULT_OOM leaked out to the #PF handler. Retrying PF