loop1: detected capacity change from 0 to 2048
==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237d266e8 of 1 bytes by task 12888 on cpu 1:
 folio_batch_add include/linux/folio_batch.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xaa/0x1f0 mm/swap.c:517
 shmem_alloc_and_add_folio mm/shmem.c:2034 [inline]
 shmem_get_folio_gfp+0x7b0/0xd60 mm/shmem.c:2564
 shmem_get_folio mm/shmem.c:2670 [inline]
 shmem_write_begin+0xfc/0x1f0 mm/shmem.c:3303
 generic_perform_write+0x183/0x490 mm/filemap.c:4325
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3478
 __kernel_write_iter+0x319/0x590 fs/read_write.c:621
 dump_emit_page fs/coredump.c:1304 [inline]
 dump_user_range+0xa73/0xd00 fs/coredump.c:1378
 elf_core_dump+0x21a2/0x2330 fs/binfmt_elf.c:2109
 coredump_write+0xacc/0xdd0 fs/coredump.c:1053
 do_coredump fs/coredump.c:1132 [inline]
 vfs_coredump+0x26dd/0x31e0 fs/coredump.c:1206
 get_signal+0xd5c/0xf20 kernel/signal.c:3022
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:98 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:252 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:323 [inline]
 irqentry_exit+0x145/0x5d0 kernel/entry/common.c:162
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

read to 0xffff888237d266e8 of 1 bytes by task 12892 on cpu 0:
 folio_batch_count include/linux/folio_batch.h:56 [inline]
 cpu_needs_drain mm/swap.c:786 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:883
 lru_add_drain_all+0x10/0x20 mm/swap.c:899
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 bdev_disk_changed+0xe7/0xe00 block/partitions/core.c:659
 loop_reread_partitions drivers/block/loop.c:447 [inline]
 loop_set_status+0x5db/0x6a0 drivers/block/loop.c:1276
 loop_set_status64 drivers/block/loop.c:1372 [inline]
 lo_ioctl+0x671/0x13a0 drivers/block/loop.c:1558
 blkdev_ioctl+0x387/0x460 block/ioctl.c:797
 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/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0c -> 0x0f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 12892 Comm: syz.1.4426 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
==================================================================
Alternate GPT is invalid, using primary GPT.
 loop1: p1 p2 p3