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BUG: KMSAN: uninit-value in zswap_is_page_same_filled mm/zswap.c:1179 [inline]
BUG: KMSAN: uninit-value in zswap_store+0x1438/0x32b0 mm/zswap.c:1271
 zswap_is_page_same_filled mm/zswap.c:1179 [inline]
 zswap_store+0x1438/0x32b0 mm/zswap.c:1271
 swap_writepage+0x122/0x340 mm/page_io.c:198
 shmem_writepage+0x1720/0x1e70 mm/shmem.c:1517
 pageout mm/vmscan.c:654 [inline]
 shrink_folio_list+0x508f/0x7760 mm/vmscan.c:1315
 evict_folios+0x9bb1/0xbaa0 mm/vmscan.c:4504
 try_to_shrink_lruvec+0x15ac/0x1b20 mm/vmscan.c:4709
 shrink_one+0x66e/0xd70 mm/vmscan.c:4748
 shrink_many mm/vmscan.c:4813 [inline]
 lru_gen_shrink_node mm/vmscan.c:4928 [inline]
 shrink_node+0x4bed/0x5890 mm/vmscan.c:5868
 kswapd_shrink_node mm/vmscan.c:6673 [inline]
 balance_pgdat mm/vmscan.c:6863 [inline]
 kswapd+0x1df1/0x4260 mm/vmscan.c:7123
 kthread+0x3ed/0x540 kernel/kthread.c:388
 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

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:268 [inline]
 copy_page_from_iter_atomic+0x12f1/0x2b70 lib/iov_iter.c:500
 generic_perform_write+0x4ae/0xc40 mm/filemap.c:3935
 shmem_file_write_iter+0x2b5/0x2e0 mm/shmem.c:2895
 vfs_iter_write+0x878/0x1100 fs/read_write.c:895
 lo_write_bvec drivers/block/loop.c:248 [inline]
 lo_write_simple drivers/block/loop.c:269 [inline]
 do_req_filebacked drivers/block/loop.c:493 [inline]
 loop_handle_cmd drivers/block/loop.c:1913 [inline]
 loop_process_work+0x142e/0x32e0 drivers/block/loop.c:1948
 loop_rootcg_workfn+0x2b/0x30 drivers/block/loop.c:1979
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x104e/0x1e70 kernel/workqueue.c:2706
 worker_thread+0xf45/0x1490 kernel/workqueue.c:2787
 kthread+0x3ed/0x540 kernel/kthread.c:388
 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Uninit was created at:
 __alloc_pages+0x9a4/0xe00 mm/page_alloc.c:4591
 alloc_pages_mpol+0x62b/0x9d0 mm/mempolicy.c:2133
 alloc_pages mm/mempolicy.c:2204 [inline]
 folio_alloc+0x1da/0x380 mm/mempolicy.c:2211
 filemap_alloc_folio+0xa5/0x430 mm/filemap.c:974
 __filemap_get_folio+0xa5a/0x1760 mm/filemap.c:1918
 grow_dev_page fs/buffer.c:1041 [inline]
 grow_buffers fs/buffer.c:1106 [inline]
 __getblk_slow fs/buffer.c:1133 [inline]
 bdev_getblk+0x3e5/0x1790 fs/buffer.c:1429
 __getblk include/linux/buffer_head.h:358 [inline]
 sb_getblk include/linux/buffer_head.h:364 [inline]
 ext4_getblk+0x3da/0xdf0 fs/ext4/inode.c:841
 ext4_xattr_inode_write fs/ext4/xattr.c:1421 [inline]
 ext4_xattr_inode_lookup_create fs/ext4/xattr.c:1594 [inline]
 ext4_xattr_set_entry+0x5485/0x64e0 fs/ext4/xattr.c:1719
 ext4_xattr_block_set+0xb94/0x51a0 fs/ext4/xattr.c:2039
 ext4_xattr_set_handle+0x1729/0x20e0 fs/ext4/xattr.c:2456
 ext4_xattr_set+0x2ea/0x540 fs/ext4/xattr.c:2558
 ext4_xattr_security_set+0x51/0x60 fs/ext4/xattr_security.c:31
 __vfs_setxattr+0x7aa/0x8b0 fs/xattr.c:201
 __vfs_setxattr_noperm+0x24f/0xa30 fs/xattr.c:235
 __vfs_setxattr_locked+0x441/0x480 fs/xattr.c:296
 vfs_setxattr+0x294/0x650 fs/xattr.c:322
 do_setxattr fs/xattr.c:630 [inline]
 setxattr+0x45f/0x540 fs/xattr.c:653
 path_setxattr+0x1f5/0x3c0 fs/xattr.c:672
 __do_sys_setxattr fs/xattr.c:688 [inline]
 __se_sys_setxattr fs/xattr.c:684 [inline]
 __x64_sys_setxattr+0xf7/0x180 fs/xattr.c:684
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x6d/0x140 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 0 PID: 77 Comm: kswapd0 Not tainted 6.7.0-syzkaller-00562-g9f8413c4a66f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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