syzbot

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BUG: KCSAN: data-race in __iomap_dio_rw / xas_set_mark

write to 0xffff88810af11ccc of 4 bytes by task 22756 on cpu 0:
 xa_mark_set lib/xarray.c:69 [inline]
 xas_set_mark+0x11e/0x130 lib/xarray.c:894
 tag_pages_for_writeback+0x9d/0x290 mm/page-writeback.c:2350
 ext4_do_writepages+0x689/0x1e70 fs/ext4/inode.c:2813
 ext4_writepages+0x11b/0x240 fs/ext4/inode.c:2965
 do_writepages+0x1db/0x350 mm/page-writeback.c:2581
 filemap_fdatawrite_wbc+0xd6/0xf0 mm/filemap.c:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0xde/0x1f0 mm/filemap.c:674
 __iomap_dio_rw+0x5dc/0x1000 fs/iomap/direct-io.c:572
 iomap_dio_rw+0x3c/0x80 fs/iomap/direct-io.c:689
 ext4_dio_read_iter fs/ext4/file.c:94 [inline]
 ext4_file_read_iter+0x20c/0x280 fs/ext4/file.c:145
 call_read_iter include/linux/fs.h:2180 [inline]
 generic_file_splice_read+0xde/0x2b0 fs/splice.c:309
 do_splice_to fs/splice.c:793 [inline]
 splice_direct_to_actor+0x26c/0x620 fs/splice.c:865
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 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+0x63/0xcd

read to 0xffff88810af11ccc of 4 bytes by task 22765 on cpu 1:
 xa_marked include/linux/xarray.h:420 [inline]
 mapping_tagged include/linux/fs.h:461 [inline]
 filemap_range_needs_writeback include/linux/pagemap.h:1139 [inline]
 __iomap_dio_rw+0x4f3/0x1000 fs/iomap/direct-io.c:527
 iomap_dio_rw+0x3c/0x80 fs/iomap/direct-io.c:689
 ext4_dio_read_iter fs/ext4/file.c:94 [inline]
 ext4_file_read_iter+0x20c/0x280 fs/ext4/file.c:145
 call_read_iter include/linux/fs.h:2180 [inline]
 io_iter_do_read io_uring/rw.c:643 [inline]
 io_read+0x2e3/0xcc0 io_uring/rw.c:766
 io_issue_sqe+0x33f/0x890 io_uring/io_uring.c:1847
 io_queue_sqe io_uring/io_uring.c:2019 [inline]
 io_submit_sqe+0x3b1/0xa50 io_uring/io_uring.c:2277
 io_submit_sqes+0x274/0x550 io_uring/io_uring.c:2388
 __do_sys_io_uring_enter io_uring/io_uring.c:3333 [inline]
 __se_sys_io_uring_enter+0x1ef/0xc40 io_uring/io_uring.c:3265
 __x64_sys_io_uring_enter+0x74/0x80 io_uring/io_uring.c:3265
 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+0x63/0xcd

value changed: 0x08000021 -> 0x10000021

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22765 Comm: syz-executor.0 Not tainted 6.2.0-rc1-syzkaller-00043-g2258c2dc850b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
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