syzbot

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BUG: KCSAN: data-race in force_page_cache_ra / set_capacity_and_notify

write to 0xffff888100405418 of 8 bytes by task 15237 on cpu 1:
 i_size_write include/linux/fs.h:878 [inline]
 set_capacity block/genhd.c:63 [inline]
 set_capacity_and_notify+0x9d/0x1d0 block/genhd.c:78
 loop_set_size+0x2e/0x70 drivers/block/loop.c:233
 loop_configure+0xb66/0xc90 drivers/block/loop.c:1059
 lo_ioctl+0x617/0x11b0
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:588
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856
 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 0xffff888100405418 of 8 bytes by task 15221 on cpu 0:
 i_size_read include/linux/fs.h:856 [inline]
 do_page_cache_ra mm/readahead.c:278 [inline]
 force_page_cache_ra+0x150/0x200 mm/readahead.c:322
 force_page_cache_readahead mm/internal.h:89 [inline]
 generic_fadvise+0x2c8/0x3f0 mm/fadvise.c:107
 vfs_fadvise mm/fadvise.c:185 [inline]
 ksys_fadvise64_64 mm/fadvise.c:199 [inline]
 __do_sys_fadvise64 mm/fadvise.c:214 [inline]
 __se_sys_fadvise64 mm/fadvise.c:212 [inline]
 __x64_sys_fadvise64+0xc5/0x100 mm/fadvise.c:212
 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: 0x0000000000000000 -> 0x0000000008100000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15221 Comm: syz-executor.3 Not tainted 5.18.0-rc3-syzkaller-00250-g42740a2ff5d3-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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