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BUG: KMSAN: uninit-value in zswap_is_page_same_filled mm/zswap.c:1452 [inline]
BUG: KMSAN: uninit-value in zswap_store+0x18e8/0x2ca0 mm/zswap.c:1528
 zswap_is_page_same_filled mm/zswap.c:1452 [inline]
 zswap_store+0x18e8/0x2ca0 mm/zswap.c:1528
 swap_writepage+0x126/0x4c0 mm/page_io.c:198
 shmem_writepage+0x1826/0x1f70 mm/shmem.c:1524
 pageout mm/vmscan.c:660 [inline]
 shrink_folio_list+0x4a55/0x7910 mm/vmscan.c:1323
 evict_folios+0x9d7f/0xcc20 mm/vmscan.c:4537
 try_to_shrink_lruvec+0x160e/0x1a50 mm/vmscan.c:4733
 shrink_one+0x66f/0xd40 mm/vmscan.c:4772
 shrink_many mm/vmscan.c:4835 [inline]
 lru_gen_shrink_node mm/vmscan.c:4935 [inline]
 shrink_node+0x4856/0x55f0 mm/vmscan.c:5894
 kswapd_shrink_node mm/vmscan.c:6704 [inline]
 balance_pgdat mm/vmscan.c:6895 [inline]
 kswapd+0x1eba/0x4460 mm/vmscan.c:7164
 kthread+0x3e2/0x540 kernel/kthread.c:388
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_page_from_iter_atomic+0x12b7/0x2b60 lib/iov_iter.c:481
 generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982
 shmem_file_write_iter+0x2bd/0x2f0 mm/shmem.c:2926
 do_iter_readv_writev+0x7e6/0x960
 vfs_iter_write+0x459/0xd00 fs/read_write.c:895
 lo_write_bvec drivers/block/loop.c:246 [inline]
 lo_write_simple drivers/block/loop.c:267 [inline]
 do_req_filebacked drivers/block/loop.c:491 [inline]
 loop_handle_cmd drivers/block/loop.c:1907 [inline]
 loop_process_work+0x1502/0x3440 drivers/block/loop.c:1942
 loop_workfn+0x48/0x60 drivers/block/loop.c:1966
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3335
 worker_thread+0xea5/0x1560 kernel/workqueue.c:3416
 kthread+0x3e2/0x540 kernel/kthread.c:388
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

Uninit was stored to memory at:
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:122 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_page_from_iter_atomic+0x12b7/0x2b60 lib/iov_iter.c:481
 generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982
 __generic_file_write_iter+0x20a/0x460 mm/filemap.c:4069
 exfat_file_write_iter+0x30b/0xa00 fs/exfat/file.c:589
 __kernel_write_iter+0x68b/0xc40 fs/read_write.c:523
 dump_emit_page fs/coredump.c:890 [inline]
 dump_user_range+0x8dc/0xee0 fs/coredump.c:951
 elf_core_dump+0x520f/0x59c0 fs/binfmt_elf.c:2077
 do_coredump+0x32d5/0x4920 fs/coredump.c:764
 get_signal+0x267e/0x2d00 kernel/signal.c:2896
 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
 do_syscall_64+0xe4/0x1f0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
 __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
 alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264
 alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335
 dump_user_range+0x4a/0xee0 fs/coredump.c:935
 elf_core_dump+0x520f/0x59c0 fs/binfmt_elf.c:2077
 do_coredump+0x32d5/0x4920 fs/coredump.c:764
 get_signal+0x267e/0x2d00 kernel/signal.c:2896
 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
 do_syscall_64+0xe4/0x1f0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

CPU: 0 PID: 79 Comm: kswapd0 Not tainted 6.8.0-syzkaller-13236-g5e74df2f8f15 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
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