================================================================== BUG: KCSAN: data-race in ondemand_readahead / ondemand_readahead write to 0xffff88812ba6a384 of 4 bytes by task 14664 on cpu 0: ondemand_readahead+0x308/0x670 mm/readahead.c:645 page_cache_async_ra+0x94/0xa0 mm/readahead.c:715 do_async_mmap_readahead mm/filemap.c:3181 [inline] filemap_fault+0x3da/0xc30 mm/filemap.c:3235 __do_fault+0xb2/0x1f0 mm/memory.c:4396 do_shared_fault mm/memory.c:4818 [inline] do_fault mm/memory.c:4892 [inline] do_pte_missing mm/memory.c:3745 [inline] handle_pte_fault mm/memory.c:5164 [inline] __handle_mm_fault mm/memory.c:5305 [inline] handle_mm_fault+0xb9a/0x27c0 mm/memory.c:5470 do_user_addr_fault arch/x86/mm/fault.c:1355 [inline] handle_page_fault arch/x86/mm/fault.c:1498 [inline] exc_page_fault+0x401/0x6d0 arch/x86/mm/fault.c:1554 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 write to 0xffff88812ba6a384 of 4 bytes by task 14676 on cpu 1: ondemand_readahead+0x350/0x670 page_cache_async_ra+0x94/0xa0 mm/readahead.c:715 do_async_mmap_readahead mm/filemap.c:3181 [inline] filemap_fault+0x3da/0xc30 mm/filemap.c:3235 __do_fault+0xb2/0x1f0 mm/memory.c:4396 do_read_fault mm/memory.c:4758 [inline] do_fault mm/memory.c:4888 [inline] do_pte_missing mm/memory.c:3745 [inline] handle_pte_fault mm/memory.c:5164 [inline] __handle_mm_fault mm/memory.c:5305 [inline] handle_mm_fault+0xd5f/0x27c0 mm/memory.c:5470 do_user_addr_fault arch/x86/mm/fault.c:1406 [inline] handle_page_fault arch/x86/mm/fault.c:1498 [inline] exc_page_fault+0x2f9/0x6d0 arch/x86/mm/fault.c:1554 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 rep_movs_alternative+0x30/0x70 arch/x86/lib/copy_user_64.S:50 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:127 [inline] _copy_from_user+0x80/0xd0 lib/usercopy.c:23 copy_from_user include/linux/uaccess.h:183 [inline] copy_msghdr_from_user+0x54/0x2a0 net/socket.c:2514 recvmsg_copy_msghdr net/socket.c:2769 [inline] ___sys_recvmsg net/socket.c:2841 [inline] do_recvmmsg+0x290/0x720 net/socket.c:2939 __sys_recvmmsg net/socket.c:3018 [inline] __do_sys_recvmmsg net/socket.c:3041 [inline] __se_sys_recvmmsg net/socket.c:3034 [inline] __x64_sys_recvmmsg+0xe2/0x160 net/socket.c:3034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b value changed: 0x00000020 -> 0x00000010 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 14676 Comm: syz-executor.2 Not tainted 6.8.0-rc7-syzkaller-00051-g67be068d31d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 ==================================================================