KCSAN: data-race in shrink_node / shrink

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in shrink_node / shrink_node mm				2	1626d	1630d	0/26	closed as invalid on 2019/11/19 15:04
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BUG: KCSAN: data-race in shrink_node / shrink_node

write to 0xffff88823fffd3e0 of 4 bytes by task 22797 on cpu 1:
 shrink_node+0x1148/0x1190 mm/vmscan.c:3337
 shrink_zones+0x2c7/0x5b0 mm/vmscan.c:3485
 do_try_to_free_pages+0x193/0x6c0 mm/vmscan.c:3541
 try_to_free_pages+0x3a5/0x8b0 mm/vmscan.c:3776
 __perform_reclaim mm/page_alloc.c:4588 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4609 [inline]
 __alloc_pages_slowpath+0x595/0xa60 mm/page_alloc.c:5007
 __alloc_pages+0x255/0x330 mm/page_alloc.c:5382
 alloc_pages_vma+0x5ee/0x770 mm/mempolicy.c:2152
 wp_page_copy+0x154/0x10e0 mm/memory.c:2989
 do_wp_page+0x4fb/0xa80
 handle_pte_fault mm/memory.c:4569 [inline]
 __handle_mm_fault mm/memory.c:4686 [inline]
 handle_mm_fault+0x975/0x1590 mm/memory.c:4784
 do_user_addr_fault+0x609/0xbe0 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x1e/0x30

write to 0xffff88823fffd3e0 of 4 bytes by task 22771 on cpu 0:
 shrink_node+0x1148/0x1190 mm/vmscan.c:3337
 shrink_zones+0x2c7/0x5b0 mm/vmscan.c:3485
 do_try_to_free_pages+0x193/0x6c0 mm/vmscan.c:3541
 try_to_free_pages+0x3a5/0x8b0 mm/vmscan.c:3776
 __perform_reclaim mm/page_alloc.c:4588 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4609 [inline]
 __alloc_pages_slowpath+0x595/0xa60 mm/page_alloc.c:5007
 __alloc_pages+0x255/0x330 mm/page_alloc.c:5382
 alloc_page_interleave+0x1e/0x120 mm/mempolicy.c:2036
 alloc_pages+0x281/0x3d0 mm/mempolicy.c:2186
 relay_alloc_buf kernel/relay.c:124 [inline]
 relay_create_buf kernel/relay.c:165 [inline]
 relay_open_buf+0x20c/0x830 kernel/relay.c:387
 relay_open+0x25b/0x570 kernel/relay.c:520
 do_blk_trace_setup+0x2fa/0x4f0 kernel/trace/blktrace.c:549
 __blk_trace_setup kernel/trace/blktrace.c:589 [inline]
 blk_trace_setup+0x9b/0x120 kernel/trace/blktrace.c:607
 sg_ioctl_common drivers/scsi/sg.c:1123 [inline]
 sg_ioctl+0xa4a/0x18e0 drivers/scsi/sg.c:1165
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000010 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 22771 Comm: syz-executor.4 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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