syzbot

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BUG: KCSAN: data-race in __filemap_remove_folio / folio_mapping

write to 0xffffea0004159f18 of 8 bytes by task 4190 on cpu 0:
 page_cache_delete mm/filemap.c:152 [inline]
 __filemap_remove_folio+0x1ac/0x2c0 mm/filemap.c:232
 filemap_remove_folio+0x6c/0x1f0 mm/filemap.c:264
 read_pages+0x293/0x540 mm/readahead.c:173
 page_cache_ra_unbounded+0x2a4/0x2e0 mm/readahead.c:269
 do_page_cache_ra mm/readahead.c:299 [inline]
 page_cache_ra_order mm/readahead.c:539 [inline]
 ondemand_readahead+0x549/0x6c0 mm/readahead.c:661
 page_cache_sync_ra+0xe0/0xf0 mm/readahead.c:688
 page_cache_sync_readahead include/linux/pagemap.h:1300 [inline]
 filemap_get_pages+0x252/0xfb0 mm/filemap.c:2505
 filemap_splice_read+0x360/0x920 mm/filemap.c:2870
 ext4_file_splice_read+0x95/0xc0 fs/ext4/file.c:158
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3b9/0x970 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0x2c67/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:41
 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+0x77/0x7f

read to 0xffffea0004159f18 of 8 bytes by task 4210 on cpu 1:
 folio_mapping+0x96/0x110 mm/util.c:799
 folio_evictable mm/internal.h:256 [inline]
 lru_add_fn+0x8d/0x430 mm/swap.c:197
 folio_batch_move_lru+0x20c/0x2c0 mm/swap.c:233
 lru_add_drain_cpu+0x77/0x260 mm/swap.c:667
 lru_add_drain+0x26/0x80 mm/swap.c:767
 free_pages_and_swap_cache+0x69/0x400 mm/swap_state.c:317
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:366 [inline]
 tlb_flush_mmu+0x2cf/0x440 mm/mmu_gather.c:373
 tlb_finish_mmu+0x8c/0x100 mm/mmu_gather.c:465
 exit_mmap+0x2cd/0x6f0 mm/mmap.c:3280
 __mmput+0x28/0x1c0 kernel/fork.c:1346
 mmput+0x4c/0x60 kernel/fork.c:1368
 exit_mm+0xe4/0x190 kernel/exit.c:569
 do_exit+0x57e/0x1740 kernel/exit.c:865
 do_group_exit+0x142/0x150 kernel/exit.c:1027
 __do_sys_exit_group kernel/exit.c:1038 [inline]
 __se_sys_exit_group kernel/exit.c:1036 [inline]
 __x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1036
 x64_sys_call+0x27c1/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:232
 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+0x77/0x7f

value changed: 0xffff8881007f6bb0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4210 Comm: syz-executor.1 Not tainted 6.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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