================================================================== BUG: KCSAN: data-race in compaction_alloc / compaction_alloc write to 0xffff88813fffbc08 of 8 bytes by task 7337 on cpu 0: update_pageblock_skip mm/compaction.c:459 [inline] isolate_freepages mm/compaction.c:1574 [inline] compaction_alloc+0x1399/0x1670 mm/compaction.c:1627 unmap_and_move+0x113/0x690 mm/migrate.c:1196 migrate_pages+0x2f7/0xfb0 mm/migrate.c:1472 compact_zone+0x1617/0x1e60 mm/compaction.c:2365 compact_node+0xe4/0x1e0 mm/compaction.c:2641 compact_nodes mm/compaction.c:2657 [inline] sysctl_compaction_handler+0x47/0x90 mm/compaction.c:2678 proc_sys_call_handler+0x3dd/0x530 fs/proc/proc_sysctl.c:591 proc_sys_write+0x1e/0x30 fs/proc/proc_sysctl.c:617 call_write_iter include/linux/fs.h:1977 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x6f9/0x7e0 fs/read_write.c:605 ksys_write+0xce/0x180 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:667 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88813fffbc08 of 8 bytes by task 7340 on cpu 1: update_pageblock_skip mm/compaction.c:458 [inline] isolate_freepages mm/compaction.c:1574 [inline] compaction_alloc+0x1375/0x1670 mm/compaction.c:1627 unmap_and_move+0x113/0x690 mm/migrate.c:1196 migrate_pages+0x2f7/0xfb0 mm/migrate.c:1472 compact_zone+0x1617/0x1e60 mm/compaction.c:2365 compact_node+0xe4/0x1e0 mm/compaction.c:2641 compact_nodes mm/compaction.c:2657 [inline] sysctl_compaction_handler+0x47/0x90 mm/compaction.c:2678 proc_sys_call_handler+0x3dd/0x530 fs/proc/proc_sysctl.c:591 proc_sys_write+0x1e/0x30 fs/proc/proc_sysctl.c:617 call_write_iter include/linux/fs.h:1977 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x6f9/0x7e0 fs/read_write.c:605 ksys_write+0xce/0x180 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:667 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7340 Comm: syz-executor.4 Tainted: G W 5.12.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================