syzbot

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BUG: KCSAN: data-race in mem_cgroup_protected / mem_cgroup_protected

write to 0xffff8880a7abd138 of 8 bytes by task 21722 on cpu 0:
 mem_cgroup_protected+0x236/0x2a0 mm/memcontrol.c:6438
 shrink_node+0x21e/0xb30 mm/vmscan.c:2775
 shrink_zones mm/vmscan.c:3025 [inline]
 do_try_to_free_pages+0x242/0x940 mm/vmscan.c:3083
 try_to_free_pages+0x1ed/0x4a0 mm/vmscan.c:3296
 __perform_reclaim mm/page_alloc.c:4121 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4142 [inline]
 __alloc_pages_slowpath+0x45c/0xee0 mm/page_alloc.c:4559
 __alloc_pages_nodemask+0x2c8/0x310 mm/page_alloc.c:4773
 alloc_pages_current+0xd1/0x170 mm/mempolicy.c:2188
 alloc_pages include/linux/gfp.h:532 [inline]
 __vmalloc_area_node mm/vmalloc.c:2432 [inline]
 __vmalloc_node_range+0x2d7/0x4c0 mm/vmalloc.c:2496
 vmalloc_user+0x65/0x80 mm/vmalloc.c:2626
 vb2_vmalloc_alloc+0xb1/0x1a0 drivers/media/common/videobuf2/videobuf2-vmalloc.c:48
 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:215 [inline]
 __vb2_queue_alloc+0x385/0x870 drivers/media/common/videobuf2/videobuf2-core.c:370
 vb2_core_create_bufs+0x205/0x5b0 drivers/media/common/videobuf2/videobuf2-core.c:849
 vb2_create_bufs+0x2d0/0x3e0 drivers/media/common/videobuf2/videobuf2-v4l2.c:742
 vb2_ioctl_create_bufs+0x27c/0x2f0 drivers/media/common/videobuf2/videobuf2-v4l2.c:947
 v4l_create_bufs drivers/media/v4l2-core/v4l2-ioctl.c:2007 [inline]
 v4l_create_bufs+0xa9/0x110 drivers/media/v4l2-core/v4l2-ioctl.c:1994
 __video_do_ioctl+0x3e1/0x720 drivers/media/v4l2-core/v4l2-ioctl.c:2910
 video_usercopy+0x418/0xa40 drivers/media/v4l2-core/v4l2-ioctl.c:3092
 video_ioctl2+0x36/0x49 drivers/media/v4l2-core/v4l2-ioctl.c:3136
 v4l2_ioctl+0xe1/0x110 drivers/media/v4l2-core/v4l2-dev.c:360
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696
 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:718
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880a7abd138 of 8 bytes by task 8093 on cpu 1:
 mem_cgroup_protected+0x236/0x2a0 mm/memcontrol.c:6438
 shrink_node+0x21e/0xb30 mm/vmscan.c:2775
 shrink_zones mm/vmscan.c:3025 [inline]
 do_try_to_free_pages+0x242/0x940 mm/vmscan.c:3083
 try_to_free_pages+0x1ed/0x4a0 mm/vmscan.c:3296
 __perform_reclaim mm/page_alloc.c:4121 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4142 [inline]
 __alloc_pages_slowpath+0x45c/0xee0 mm/page_alloc.c:4559
 __alloc_pages_nodemask+0x2c8/0x310 mm/page_alloc.c:4773
 alloc_pages_current+0xd1/0x170 mm/mempolicy.c:2188
 alloc_pages include/linux/gfp.h:532 [inline]
 __page_cache_alloc mm/filemap.c:981 [inline]
 __page_cache_alloc+0x183/0x1a0 mm/filemap.c:966
 __do_page_cache_readahead+0x13e/0x390 mm/readahead.c:196
 ra_submit mm/internal.h:62 [inline]
 do_sync_mmap_readahead mm/filemap.c:2443 [inline]
 filemap_fault+0xdad/0xf90 mm/filemap.c:2529
 ext4_filemap_fault+0x59/0x72 fs/ext4/inode.c:6292
 __do_fault+0xae/0x1f0 mm/memory.c:3092
 do_read_fault mm/memory.c:3489 [inline]
 do_fault mm/memory.c:3618 [inline]
 handle_pte_fault mm/memory.c:3849 [inline]
 __handle_mm_fault+0x1f90/0x2c70 mm/memory.c:3973
 handle_mm_fault+0x21b/0x530 mm/memory.c:4010
 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
 __do_page_fault+0x3fb/0x9e0 arch/x86/mm/fault.c:1506
 do_page_fault+0x54/0x233 arch/x86/mm/fault.c:1530
 page_fault+0x34/0x40 arch/x86/entry/entry_64.S:1202

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8093 Comm: syz-fuzzer Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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