syzbot

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BUG: KCSAN: data-race in __loop_clr_fd / handle_mm_fault

write to 0xffff888106b42460 of 4 bytes by task 27322 on cpu 1:
 mapping_set_gfp_mask include/linux/pagemap.h:290 [inline]
 __loop_clr_fd+0x214/0x3c0 drivers/block/loop.c:1168
 loop_clr_fd drivers/block/loop.c:1257 [inline]
 lo_ioctl+0xd8c/0x1290 drivers/block/loop.c:1563
 blkdev_ioctl+0x215/0x440 block/ioctl.c:616
 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+0x63/0xcd

read to 0xffff888106b42460 of 4 bytes by task 3116 on cpu 0:
 mapping_gfp_mask include/linux/pagemap.h:274 [inline]
 __get_fault_gfp_mask mm/memory.c:2920 [inline]
 __handle_mm_fault mm/memory.c:4990 [inline]
 handle_mm_fault+0x2a6/0xb20 mm/memory.c:5219
 do_user_addr_fault+0x4a1/0x980 arch/x86/mm/fault.c:1428
 handle_page_fault arch/x86/mm/fault.c:1519 [inline]
 exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1575
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570

value changed: 0x00100c0a -> 0x00100cca

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3116 Comm: syz-executor.5 Not tainted 6.2.0-rc5-syzkaller-00108-g83abd4d4c4be-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
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