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BUG: KCSAN: data-race in do_mpage_readpage / set_blocksize

write to 0xffff8881021210b6 of 1 bytes by task 20709 on cpu 1:
 set_blocksize+0x227/0x290 block/bdev.c:151
 sb_set_blocksize block/bdev.c:161 [inline]
 sb_min_blocksize+0x83/0x110 block/bdev.c:177
 isofs_fill_super+0x7d7/0x1840 fs/isofs/inode.c:658
 mount_bdev+0x1c4/0x260 fs/super.c:1391
 isofs_mount+0x31/0x40 fs/isofs/inode.c:1564
 legacy_get_tree+0x74/0xd0 fs/fs_context.c:611
 vfs_get_tree+0x51/0x190 fs/super.c:1519
 do_new_mount+0x203/0x660 fs/namespace.c:3335
 path_mount+0x496/0xb30 fs/namespace.c:3662
 do_mount fs/namespace.c:3675 [inline]
 __do_sys_mount fs/namespace.c:3884 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3861
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881021210b6 of 1 bytes by task 26186 on cpu 0:
 do_mpage_readpage+0x6c/0xdf0 fs/mpage.c:163
 mpage_readahead+0x1b2/0x2d0 fs/mpage.c:382
 blkdev_readahead+0x1c/0x20 block/fops.c:401
 read_pages+0xa6/0x560 mm/readahead.c:160
 page_cache_ra_unbounded+0x2a9/0x2e0 mm/readahead.c:269
 do_page_cache_ra mm/readahead.c:299 [inline]
 force_page_cache_ra mm/readahead.c:330 [inline]
 page_cache_sync_ra+0x251/0x2a0 mm/readahead.c:704
 page_cache_sync_readahead include/linux/pagemap.h:1213 [inline]
 filemap_get_pages+0x254/0xea0 mm/filemap.c:2563
 filemap_read+0x1fb/0x670 mm/filemap.c:2658
 blkdev_read_iter+0x217/0x2c0 block/fops.c:616
 call_read_iter include/linux/fs.h:1865 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3da/0x5c0 fs/read_write.c:470
 ksys_read+0xeb/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0c -> 0x0a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 26186 Comm: udevd Not tainted 6.4.0-syzkaller-12155-ga452483508d7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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I/O error, dev loop5, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2