EXT4-fs (loop4): failed to open journal device unknown-block(0,0) -ENXIO ================================================================== BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru read-write to 0xffff888237c26528 of 1 bytes by task 3591 on cpu 0: folio_batch_add include/linux/folio_batch.h:77 [inline] __folio_batch_add_and_move mm/swap.c:229 [inline] folio_add_lru+0xa4/0x250 mm/swap.c:562 shmem_alloc_and_add_folio mm/shmem.c:2008 [inline] shmem_get_folio_gfp+0x7cc/0xd90 mm/shmem.c:2502 shmem_fault+0xf6/0x250 mm/shmem.c:2703 __do_fault mm/memory.c:5425 [inline] do_read_fault mm/memory.c:5860 [inline] do_fault mm/memory.c:5994 [inline] do_pte_missing mm/memory.c:4566 [inline] handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0x167a/0x2da0 mm/memory.c:6686 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x129c/0x1f10 mm/gup.c:1428 populate_vma_page_range mm/gup.c:1860 [inline] __mm_populate+0x242/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:4171 [inline] vm_mmap_pgoff+0x23b/0x2d0 mm/util.c:586 ksys_mmap_pgoff+0xc1/0x310 mm/mmap.c:606 x64_sys_call+0x14df/0x3020 arch/x86/include/generated/asm/syscalls_64.h:10 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff888237c26528 of 1 bytes by task 3584 on cpu 1: folio_batch_count include/linux/folio_batch.h:56 [inline] cpu_needs_drain mm/swap.c:831 [inline] __lru_add_drain_all+0x17e/0x450 mm/swap.c:928 lru_add_drain_all+0x10/0x20 mm/swap.c:944 invalidate_bdev+0x47/0x70 block/bdev.c:101 __ext4_fill_super fs/ext4/super.c:5803 [inline] ext4_fill_super+0x2c8c/0x3760 fs/ext4/super.c:5828 get_tree_bdev_flags+0x291/0x300 fs/super.c:1634 get_tree_bdev+0x1f/0x30 fs/super.c:1657 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5860 vfs_get_tree+0x57/0x1d0 fs/super.c:1694 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3765 [inline] do_new_mount+0x288/0x8d0 fs/namespace.c:3841 path_mount+0x4ad/0xb90 fs/namespace.c:4161 do_mount fs/namespace.c:4174 [inline] __do_sys_mount fs/namespace.c:4390 [inline] __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4367 __x64_sys_mount+0x67/0x80 fs/namespace.c:4367 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+0x136/0x3c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x17 -> 0x18 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 3584 Comm: syz.4.20 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 ==================================================================