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EXT4-fs (loop7): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
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BUG: KCSAN: data-race in do_sync_mmap_readahead / do_sync_mmap_readahead

write to 0xffff88811b1c0c90 of 8 bytes by task 15564 on cpu 1:
 do_sync_mmap_readahead+0x2d8/0x350 mm/filemap.c:-1
 filemap_fault+0x362/0xbb0 mm/filemap.c:3549
 __do_fault+0xbc/0x200 mm/memory.c:5323
 do_read_fault mm/memory.c:5758 [inline]
 do_fault mm/memory.c:5892 [inline]
 do_pte_missing mm/memory.c:4404 [inline]
 handle_pte_fault mm/memory.c:6276 [inline]
 __handle_mm_fault mm/memory.c:6414 [inline]
 handle_mm_fault+0x11d7/0x3030 mm/memory.c:6583
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1023/0x1ea0 mm/gup.c:1428
 __get_user_pages_locked mm/gup.c:1692 [inline]
 __gup_longterm_locked+0xbad/0xe30 mm/gup.c:2476
 pin_user_pages_remote+0x7e/0xb0 mm/gup.c:3363
 process_vm_rw_single_vec mm/process_vm_access.c:106 [inline]
 process_vm_rw_core mm/process_vm_access.c:216 [inline]
 process_vm_rw+0x49b/0x9c0 mm/process_vm_access.c:284
 __do_sys_process_vm_readv mm/process_vm_access.c:296 [inline]
 __se_sys_process_vm_readv mm/process_vm_access.c:292 [inline]
 __x64_sys_process_vm_readv+0x78/0x90 mm/process_vm_access.c:292
 x64_sys_call+0x148a/0x3000 arch/x86/include/generated/asm/syscalls_64.h:311
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88811b1c0c90 of 8 bytes by task 15531 on cpu 0:
 do_sync_mmap_readahead+0x2d8/0x350 mm/filemap.c:-1
 filemap_fault+0x362/0xbb0 mm/filemap.c:3549
 __do_fault+0xbc/0x200 mm/memory.c:5323
 do_read_fault mm/memory.c:5758 [inline]
 do_fault mm/memory.c:5892 [inline]
 do_pte_missing mm/memory.c:4404 [inline]
 handle_pte_fault mm/memory.c:6276 [inline]
 __handle_mm_fault mm/memory.c:6414 [inline]
 handle_mm_fault+0x11d7/0x3030 mm/memory.c:6583
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1023/0x1ea0 mm/gup.c:1428
 populate_vma_page_range mm/gup.c:1860 [inline]
 __mm_populate+0x242/0x390 mm/gup.c:1963
 mm_populate include/linux/mm.h:3705 [inline]
 vm_mmap_pgoff+0x23b/0x2d0 mm/util.c:586
 ksys_mmap_pgoff+0x267/0x310 mm/mmap.c:604
 x64_sys_call+0x16bb/0x3000 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000000001d -> 0x0000000000000075

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 15531 Comm: syz.7.3423 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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