syzbot

loop3: p3 start 11362048 is beyond EOD, truncated
==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237d26668 of 1 bytes by task 21917 on cpu 1:
 folio_batch_add include/linux/pagevec.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa4/0x1e0 mm/swap.c:511
 shmem_alloc_and_add_folio mm/shmem.c:2031 [inline]
 shmem_get_folio_gfp+0x7b0/0xd60 mm/shmem.c:2567
 shmem_fault+0xf6/0x250 mm/shmem.c:2768
 __do_fault+0xbc/0x200 mm/memory.c:5364
 do_read_fault mm/memory.c:5799 [inline]
 do_fault mm/memory.c:5933 [inline]
 do_pte_missing mm/memory.c:4477 [inline]
 handle_pte_fault mm/memory.c:6317 [inline]
 __handle_mm_fault mm/memory.c:6455 [inline]
 handle_mm_fault+0x11d7/0x3020 mm/memory.c:6624
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1023/0x1ea0 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:3899 [inline]
 vm_mmap_pgoff+0x23b/0x2d0 mm/util.c:586
 ksys_mmap_pgoff+0xc1/0x310 mm/mmap.c:605
 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+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d26668 of 1 bytes by task 3000 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:877
 lru_add_drain_all+0x10/0x20 mm/swap.c:893
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 bdev_disk_changed+0xeb/0xd40 block/partitions/core.c:658
 blkdev_get_whole+0x1f5/0x2d0 block/bdev.c:764
 bdev_open+0x280/0x7e0 block/bdev.c:973
 bdev_file_open_by_dev+0x1e6/0x250 block/bdev.c:1075
 disk_scan_partitions+0x148/0x1b0 block/genhd.c:387
 blkdev_common_ioctl+0x1236/0x20b0 block/ioctl.c:719
 blkdev_ioctl+0x31f/0x460 block/ioctl.c:798
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x1563/0x3020 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x13 -> 0x14

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3000 Comm: udevd Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================
 loop3: p3 p4 < >
loop3: p3 start 11362048 is beyond EOD, truncated
 loop3: p3 p4 < >
loop3: p3 start 11362048 is beyond EOD, truncated