syzbot

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BUG: KCSAN: data-race in do_mpage_readpage / set_blocksize

write to 0xffff888101ba5496 of 1 bytes by task 20746 on cpu 1:
 set_blocksize+0x20a/0x270 block/bdev.c:152
 sb_set_blocksize block/bdev.c:162 [inline]
 sb_min_blocksize+0x92/0x110 block/bdev.c:178
 __ext4_fill_super fs/ext4/super.c:4420 [inline]
 ext4_fill_super+0x1fc/0x3a80 fs/ext4/super.c:5599
 get_tree_bdev+0x2b4/0x3b0 fs/super.c:1292
 vfs_get_tree+0x49/0x190 fs/super.c:1497
 do_new_mount+0x200/0x650 fs/namespace.c:3040
 path_mount+0x4b1/0xb60 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888101ba5496 of 1 bytes by task 25615 on cpu 0:
 do_mpage_readpage+0x6c/0xf20 fs/mpage.c:135
 mpage_readahead+0x18b/0x3f0 fs/mpage.c:356
 blkdev_readahead+0x18/0x20 block/fops.c:382
 read_pages+0xa0/0x7c0 mm/readahead.c:158
 page_cache_ra_unbounded+0x2a8/0x2e0 mm/readahead.c:262
 do_page_cache_ra mm/readahead.c:292 [inline]
 force_page_cache_ra+0x1c6/0x200 mm/readahead.c:323
 page_cache_sync_ra+0xc8/0xf0 mm/readahead.c:692
 page_cache_sync_readahead include/linux/pagemap.h:1185 [inline]
 filemap_get_pages mm/filemap.c:2592 [inline]
 filemap_read+0x3e5/0x1400 mm/filemap.c:2679
 blkdev_read_iter+0x2c6/0x370 block/fops.c:596
 call_read_iter include/linux/fs.h:2046 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 vfs_read+0x5a5/0x6a0 fs/read_write.c:482
 ksys_read+0xe8/0x1a0 fs/read_write.c:620
 __do_sys_read fs/read_write.c:630 [inline]
 __se_sys_read fs/read_write.c:628 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:628
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0c -> 0x0a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25615 Comm: udevd Not tainted 5.18.0-syzkaller-00511-g140e40e39a29-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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