syzbot

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BUG: KCSAN: data-race in compact_zone / isolate_migratepages_block

write to 0xffff88823fffab90 of 8 bytes by task 11951 on cpu 1:
 update_cached_migrate mm/compaction.c:504 [inline]
 isolate_migratepages_block+0x24a5/0x2740 mm/compaction.c:1358
 isolate_migratepages mm/compaction.c:2194 [inline]
 compact_zone+0x1e1e/0x2930 mm/compaction.c:2641
 compact_zone_order mm/compaction.c:2806 [inline]
 try_to_compact_pages+0x388/0x920 mm/compaction.c:2862
 __alloc_pages_direct_compact+0x6f/0x1e0 mm/page_alloc.c:3655
 __alloc_pages_slowpath+0x567/0xd70 mm/page_alloc.c:4333
 __alloc_pages_noprof+0x26d/0x360 mm/page_alloc.c:4713
 alloc_pages_mpol_noprof+0xb1/0x1e0 mm/mempolicy.c:2263
 alloc_pages_noprof+0xe1/0x100 mm/mempolicy.c:2343
 io_mem_alloc_compound io_uring/memmap.c:28 [inline]
 io_pages_map+0xbe/0x4e0 io_uring/memmap.c:72
 io_allocate_scq_urings+0x10d/0x300 io_uring/io_uring.c:3313
 io_uring_create+0x51f/0x920 io_uring/io_uring.c:3496
 io_uring_setup io_uring/io_uring.c:3609 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:3636 [inline]
 __se_sys_io_uring_setup+0x1d2/0x1e0 io_uring/io_uring.c:3630
 __x64_sys_io_uring_setup+0x31/0x40 io_uring/io_uring.c:3630
 x64_sys_call+0x1f7e/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88823fffab90 of 8 bytes by task 11941 on cpu 0:
 compact_zone+0x2393/0x2930 mm/compaction.c:2650
 compact_zone_order mm/compaction.c:2806 [inline]
 try_to_compact_pages+0x388/0x920 mm/compaction.c:2862
 __alloc_pages_direct_compact+0x6f/0x1e0 mm/page_alloc.c:3655
 __alloc_pages_slowpath+0x236/0xd70 mm/page_alloc.c:4250
 __alloc_pages_noprof+0x26d/0x360 mm/page_alloc.c:4713
 alloc_pages_mpol_noprof+0xb1/0x1e0 mm/mempolicy.c:2263
 alloc_pages_noprof+0xe1/0x100 mm/mempolicy.c:2343
 io_mem_alloc_compound io_uring/memmap.c:28 [inline]
 io_pages_map+0xbe/0x4e0 io_uring/memmap.c:72
 io_allocate_scq_urings+0x283/0x300 io_uring/io_uring.c:3338
 io_uring_create+0x51f/0x920 io_uring/io_uring.c:3496
 io_uring_setup io_uring/io_uring.c:3609 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:3636 [inline]
 __se_sys_io_uring_setup+0x1d2/0x1e0 io_uring/io_uring.c:3630
 __x64_sys_io_uring_setup+0x31/0x40 io_uring/io_uring.c:3630
 x64_sys_call+0x1f7e/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000169000 -> 0x0000000000169a00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 11941 Comm: syz.0.2406 Not tainted 6.11.0-rc3-syzkaller-00060-gd07b43284ab3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
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