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RDX: 0000000020000000 RSI: 00000000c0184900 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f72b39b86d4
R13: 00000000004c0aa9 R14: 00000000004d2be8 R15: 00000000ffffffff
==================================================================
BUG: KMSAN: uninit-value in shrink_node+0x9d8/0x2140 mm/vmscan.c:2742
CPU: 0 PID: 10271 Comm: rs:main Q:Reg Not tainted 5.1.0-rc2+ #21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x131/0x2a0 mm/kmsan/kmsan.c:624
 __msan_warning+0x7a/0xf0 mm/kmsan/kmsan_instr.c:310
 shrink_node+0x9d8/0x2140 mm/vmscan.c:2742
 shrink_zones mm/vmscan.c:2953 [inline]
 do_try_to_free_pages+0x55e/0x20b0 mm/vmscan.c:3015
 try_to_free_pages+0xc58/0x1720 mm/vmscan.c:3231
 __perform_reclaim mm/page_alloc.c:4004 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4026 [inline]
 __alloc_pages_slowpath mm/page_alloc.c:4419 [inline]
 __alloc_pages_nodemask+0x2ff8/0x5e90 mm/page_alloc.c:4633
 alloc_pages_current+0x6a4/0x9c0 mm/mempolicy.c:2106
 alloc_pages include/linux/gfp.h:511 [inline]
 __page_cache_alloc+0x95/0x320 mm/filemap.c:948
 pagecache_get_page+0x4e5/0x14e0 mm/filemap.c:1644
 grab_cache_page_write_begin+0x100/0x180 mm/filemap.c:3252
 ext4_da_write_begin+0xb1e/0x17d0 fs/ext4/inode.c:3071
 generic_perform_write+0x412/0x990 mm/filemap.c:3302
 __generic_file_write_iter+0x422/0xa30 mm/filemap.c:3431
 ext4_file_write_iter+0x18ad/0x2130 fs/ext4/file.c:266
 call_write_iter include/linux/fs.h:1863 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x99f/0xc30 fs/read_write.c:487
 vfs_write+0x481/0x920 fs/read_write.c:549
 ksys_write fs/read_write.c:598 [inline]
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write+0x17a/0x370 fs/read_write.c:607
 __x64_sys_write+0x4a/0x70 fs/read_write.c:607
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x7f4f6e48419d
Code: d1 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 be fa ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 07 fb ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f4f6ca24f90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007f4f6e48419d
RDX: 0000000000000400 RSI: 0000000000842a90 RDI: 0000000000000005
RBP: 0000000000842a90 R08: 0000000000842e35 R09: 00007f4f6de01887
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f4f6ca25410 R14: 000000000087d160 R15: 0000000000842890

Local variable description: ----b@generic_make_request_checks
Variable was created at:
 generic_make_request_checks+0xbe/0x2b10 block/blk-core.c:875
 generic_make_request+0x257/0x19f0 block/blk-core.c:1032
==================================================================