=====================================================
BUG: KMSAN: uninit-value in arch_atomic_fetch_add arch/x86/include/asm/atomic.h:184 [inline]
BUG: KMSAN: uninit-value in atomic_fetch_add_relaxed include/asm-generic/atomic-instrumented.h:143 [inline]
BUG: KMSAN: uninit-value in __refcount_add include/linux/refcount.h:193 [inline]
BUG: KMSAN: uninit-value in __refcount_inc include/linux/refcount.h:250 [inline]
BUG: KMSAN: uninit-value in refcount_inc include/linux/refcount.h:267 [inline]
BUG: KMSAN: uninit-value in get_task_struct include/linux/sched/task.h:104 [inline]
BUG: KMSAN: uninit-value in rwsem_mark_wake+0xb25/0xd60 kernel/locking/rwsem.c:513
 arch_atomic_fetch_add arch/x86/include/asm/atomic.h:184 [inline]
 atomic_fetch_add_relaxed include/asm-generic/atomic-instrumented.h:143 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_task_struct include/linux/sched/task.h:104 [inline]
 rwsem_mark_wake+0xb25/0xd60 kernel/locking/rwsem.c:513
 rwsem_wake kernel/locking/rwsem.c:1176 [inline]
 __up_write kernel/locking/rwsem.c:1322 [inline]
 up_write+0x1b0/0x220 kernel/locking/rwsem.c:1459
 anon_vma_unlock_write include/linux/rmap.h:125 [inline]
 split_huge_page_to_list+0x1e03/0x2110 mm/huge_memory.c:2781
 shrink_page_list+0x2c7c/0x7af0 mm/vmscan.c:1475
 shrink_inactive_list+0xb33/0x17a0 mm/vmscan.c:2145
 shrink_list mm/vmscan.c:2367 [inline]
 shrink_lruvec+0x7a8/0x1610 mm/vmscan.c:2662
 shrink_node_memcgs+0x5d3/0xc70 mm/vmscan.c:2850
 shrink_node+0x1995/0x34a0 mm/vmscan.c:2967
 kswapd_shrink_node mm/vmscan.c:3710 [inline]
 balance_pgdat+0x1401/0x2520 mm/vmscan.c:3868
 kswapd+0x515/0x8b0 mm/vmscan.c:4125
 kthread+0x4f9/0x610 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Local variable ----pmde.sroa.0@page_vma_mapped_walk created at:
 page_vma_mapped_walk+0xd6/0x36c0 mm/page_vma_mapped.c:161
 page_referenced_one+0x771/0xda0 mm/rmap.c:782
=====================================================
Kernel panic - not syncing: panic_on_kmsan set ...
CPU: 1 PID: 2016 Comm: kswapd0 Tainted: G    B             5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x25a/0x2f6 lib/dump_stack.c:120
 panic+0x4c7/0xe98 kernel/panic.c:231
 kmsan_report+0x2ee/0x300 mm/kmsan/report.c:179
 __msan_warning+0xd7/0x150 mm/kmsan/instrumentation.c:208
 arch_atomic_fetch_add arch/x86/include/asm/atomic.h:184 [inline]
 atomic_fetch_add_relaxed include/asm-generic/atomic-instrumented.h:143 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_task_struct include/linux/sched/task.h:104 [inline]
 rwsem_mark_wake+0xb25/0xd60 kernel/locking/rwsem.c:513
 rwsem_wake kernel/locking/rwsem.c:1176 [inline]
 __up_write kernel/locking/rwsem.c:1322 [inline]
 up_write+0x1b0/0x220 kernel/locking/rwsem.c:1459
 anon_vma_unlock_write include/linux/rmap.h:125 [inline]
 split_huge_page_to_list+0x1e03/0x2110 mm/huge_memory.c:2781
 shrink_page_list+0x2c7c/0x7af0 mm/vmscan.c:1475
 shrink_inactive_list+0xb33/0x17a0 mm/vmscan.c:2145
 shrink_list mm/vmscan.c:2367 [inline]
 shrink_lruvec+0x7a8/0x1610 mm/vmscan.c:2662
 shrink_node_memcgs+0x5d3/0xc70 mm/vmscan.c:2850
 shrink_node+0x1995/0x34a0 mm/vmscan.c:2967
 kswapd_shrink_node mm/vmscan.c:3710 [inline]
 balance_pgdat+0x1401/0x2520 mm/vmscan.c:3868
 kswapd+0x515/0x8b0 mm/vmscan.c:4125
 kthread+0x4f9/0x610 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Kernel Offset: disabled
Rebooting in 86400 seconds..