================================================================== BUG: KCSAN: data-race in shmem_add_to_page_cache / shmem_getpage_gfp read-write to 0xffff888150096bd0 of 8 bytes by task 10203 on cpu 1: shmem_add_to_page_cache+0x802/0x8f0 mm/shmem.c:745 shmem_getpage_gfp+0x7af/0x1750 mm/shmem.c:1939 shmem_fault+0xd2/0x350 mm/shmem.c:2116 __do_fault mm/memory.c:4165 [inline] do_read_fault mm/memory.c:4511 [inline] do_fault+0x500/0xb20 mm/memory.c:4640 handle_pte_fault mm/memory.c:4904 [inline] __handle_mm_fault mm/memory.c:5043 [inline] handle_mm_fault+0x889/0xa90 mm/memory.c:5141 faultin_page mm/gup.c:953 [inline] __get_user_pages+0x34a/0xbf0 mm/gup.c:1174 populate_vma_page_range mm/gup.c:1518 [inline] __mm_populate+0x26e/0x3a0 mm/gup.c:1631 mm_populate include/linux/mm.h:2706 [inline] vm_mmap_pgoff+0x160/0x1f0 mm/util.c:557 ksys_mmap_pgoff+0xc2/0x320 mm/mmap.c:1633 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 0xffff888150096bd0 of 8 bytes by task 10183 on cpu 0: shmem_recalc_inode mm/shmem.c:362 [inline] shmem_getpage_gfp+0xd8b/0x1750 mm/shmem.c:1949 shmem_fault+0xd2/0x350 mm/shmem.c:2116 __do_fault mm/memory.c:4165 [inline] do_read_fault mm/memory.c:4511 [inline] do_fault+0x500/0xb20 mm/memory.c:4640 handle_pte_fault mm/memory.c:4904 [inline] __handle_mm_fault mm/memory.c:5043 [inline] handle_mm_fault+0x889/0xa90 mm/memory.c:5141 do_user_addr_fault+0x4cd/0x940 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1484 [inline] exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1540 asm_exc_page_fault+0x22/0x30 fault_in_readable+0x115/0x1a0 fault_in_iov_iter_readable+0xd7/0x140 lib/iov_iter.c:458 generic_perform_write+0x116/0x3f0 mm/filemap.c:3769 ext4_buffered_write_iter+0x222/0x330 fs/ext4/file.c:270 ext4_file_write_iter+0x2e3/0x1210 call_write_iter include/linux/fs.h:2058 [inline] new_sync_write fs/read_write.c:504 [inline] vfs_write+0x71c/0x890 fs/read_write.c:591 ksys_write+0xe8/0x1a0 fs/read_write.c:644 __do_sys_write fs/read_write.c:656 [inline] __se_sys_write fs/read_write.c:653 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:653 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 value changed: 0x00000000000000e1 -> 0x00000000000000e2 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10183 Comm: syz-executor.4 Not tainted 5.19.0-rc7-syzkaller-00007-g353f7988dd84-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 ==================================================================