loop3: detected capacity change from 0 to 2048
ext4: Unknown parameter 'va'
==================================================================
BUG: KCSAN: data-race in shmem_add_to_page_cache / shmem_get_folio_gfp

read-write to 0xffff888108a15860 of 8 bytes by task 22558 on cpu 0:
 shmem_add_to_page_cache+0x40a/0x510 mm/shmem.c:742
 shmem_get_folio_gfp+0x923/0x1200 mm/shmem.c:1978
 shmem_fault+0xe5/0x3d0 mm/shmem.c:2163
 __do_fault mm/memory.c:4176 [inline]
 do_read_fault mm/memory.c:4530 [inline]
 do_fault mm/memory.c:4659 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x12f4/0x2c60 mm/memory.c:5243
 faultin_page mm/gup.c:969 [inline]
 __get_user_pages+0x363/0xc30 mm/gup.c:1191
 populate_vma_page_range mm/gup.c:1587 [inline]
 __mm_populate+0x23d/0x370 mm/gup.c:1696
 mm_populate include/linux/mm.h:3176 [inline]
 __do_sys_remap_file_pages mm/mmap.c:2908 [inline]
 __se_sys_remap_file_pages+0x43a/0x570 mm/mmap.c:2834
 __x64_sys_remap_file_pages+0x67/0x80 mm/mmap.c:2834
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888108a15860 of 8 bytes by task 22532 on cpu 1:
 shmem_recalc_inode mm/shmem.c:360 [inline]
 shmem_get_folio_gfp+0xe1e/0x1200 mm/shmem.c:1988
 shmem_fault+0xe5/0x3d0 mm/shmem.c:2163
 __do_fault mm/memory.c:4176 [inline]
 do_read_fault mm/memory.c:4530 [inline]
 do_fault mm/memory.c:4659 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x12f4/0x2c60 mm/memory.c:5243
 do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x67e/0x780 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
 fault_in_readable+0xf8/0x1b0
 fault_in_iov_iter_readable+0x82/0x180 lib/iov_iter.c:216
 generic_perform_write+0x106/0x3d0 mm/filemap.c:3936
 ext4_buffered_write_iter+0x240/0x3e0 fs/ext4/file.c:300
 ext4_file_write_iter+0xdd/0x10f0
 call_write_iter include/linux/fs.h:1872 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x4ab/0x7d0 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000000000a1 -> 0x00000000000000a2

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22532 Comm: syz-executor.3 Not tainted 6.4.0-syzkaller-01371-g04fc8904d5d1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
==================================================================