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 3511 on cpu 0:
 i_size_write include/linux/fs.h:907 [inline]
 set_capacity block/genhd.c:62 [inline]
 set_capacity_and_notify+0x9d/0x1d0 block/genhd.c:77
 loop_set_size drivers/block/loop.c:231 [inline]
 loop_configure+0xd53/0xf50 drivers/block/loop.c:1054
 lo_ioctl+0x633/0x1280
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:588
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888100405418 of 8 bytes by task 3449 on cpu 1:
 i_size_read include/linux/fs.h:885 [inline]
 do_page_cache_ra mm/readahead.c:255 [inline]
 force_page_cache_ra+0x170/0x220 mm/readahead.c:300
 force_page_cache_readahead mm/internal.h:92 [inline]
 generic_fadvise+0x2e0/0x430 mm/fadvise.c:107
 vfs_fadvise mm/fadvise.c:186 [inline]
 ksys_fadvise64_64 mm/fadvise.c:200 [inline]
 __do_sys_fadvise64 mm/fadvise.c:215 [inline]
 __se_sys_fadvise64 mm/fadvise.c:213 [inline]
 __x64_sys_fadvise64+0xc5/0x100 mm/fadvise.c:213
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000000 -> 0x0000000000018400

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3449 Comm: syz-executor.4 Not tainted 5.17.0-rc2-syzkaller-00353-g90c9e950c0de-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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