BUG: KCSAN: data-race in blkdev_llseek / set_capacity_and_notify write to 0xffff8881027a1460 of 8 bytes by task 7267 on cpu 1: i_size_write include/linux/fs.h:871 [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:237 loop_configure+0xb1b/0xc20 drivers/block/loop.c:1095 lo_ioctl+0x641/0x1290 blkdev_ioctl+0x20e/0x440 block/ioctl.c:614 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+0x46/0xb0 read to 0xffff8881027a1460 of 8 bytes by task 31315 on cpu 0: i_size_read include/linux/fs.h:849 [inline] blkdev_llseek+0x4c/0x80 block/fops.c:434 vfs_llseek fs/read_write.c:300 [inline] ksys_lseek fs/read_write.c:313 [inline] __do_sys_lseek fs/read_write.c:324 [inline] __se_sys_lseek fs/read_write.c:322 [inline] __x64_sys_lseek+0xf0/0x150 fs/read_write.c:322 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+0x46/0xb0 value changed: 0x0000000000000000 -> 0x0000000008100000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 31315 Comm: udevd Not tainted 5.19.0-rc3-syzkaller-00048-gde5c208d533a-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== blk_print_req_error: 25 callbacks suppressed I/O error, dev loop1, sector 264064 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0 I/O error, dev loop1, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0