loop0: detected capacity change from 0 to 2048
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BUG: KCSAN: data-race in __filemap_add_folio / filemap_write_and_wait_range

read-write to 0xffff8881004c0bb0 of 8 bytes by task 3257 on cpu 1:
 __filemap_add_folio+0x5b5/0x7f0 mm/filemap.c:928
 filemap_add_folio+0x9f/0x1b0 mm/filemap.c:969
 page_cache_ra_unbounded+0x1c1/0x350 mm/readahead.c:275
 do_page_cache_ra mm/readahead.c:327 [inline]
 force_page_cache_ra mm/readahead.c:356 [inline]
 page_cache_sync_ra+0x252/0x680 mm/readahead.c:575
 filemap_get_pages+0x2ba/0x11b0 mm/filemap.c:2590
 filemap_read+0x231/0x8d0 mm/filemap.c:2701
 blkdev_read_iter+0x227/0x2d0 block/fops.c:796
 new_sync_read fs/read_write.c:489 [inline]
 vfs_read+0x5e6/0x710 fs/read_write.c:570
 ksys_read+0xeb/0x1b0 fs/read_write.c:713
 __do_sys_read fs/read_write.c:722 [inline]
 __se_sys_read fs/read_write.c:720 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:720
 x64_sys_call+0x2a3b/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881004c0bb0 of 8 bytes by task 5282 on cpu 0:
 mapping_needs_writeback mm/filemap.c:641 [inline]
 filemap_write_and_wait_range+0x5c/0x370 mm/filemap.c:690
 filemap_write_and_wait include/linux/pagemap.h:68 [inline]
 sync_blockdev block/bdev.c:222 [inline]
 set_blocksize+0x1d3/0x270 block/bdev.c:172
 sb_set_blocksize+0x7e/0x100 block/bdev.c:186
 ext4_load_super fs/ext4/super.c:5112 [inline]
 __ext4_fill_super fs/ext4/super.c:5264 [inline]
 ext4_fill_super+0x1345/0x3580 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x2b4/0x330 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5758
 vfs_get_tree+0x56/0x1e0 fs/super.c:1759
 do_new_mount+0x246/0x6b0 fs/namespace.c:3878
 path_mount+0x49b/0xb30 fs/namespace.c:4205
 do_mount fs/namespace.c:4218 [inline]
 __do_sys_mount fs/namespace.c:4429 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4406
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4406
 x64_sys_call+0xd11/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000001 -> 0x0000000000000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5282 Comm: syz.0.628 Not tainted 6.14.0-syzkaller-12886-ga1b5bd45d4ee #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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