[moderation] [mm?] KCSAN: data-race in compact_zone / compact_zone (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3b47bc037bd4 Merge tag 'pinctrl-v6.7-2' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1424fcb4e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=585869067cd7ce59
dashboard link: https://syzkaller.appspot.com/bug?extid=81e9a7260235b6971461
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/231e21487056/disk-3b47bc03.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/eae871bb6b73/vmlinux-3b47bc03.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0c20f8f08d47/bzImage-3b47bc03.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+81e9a7...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in compact_zone / compact_zone

write to 0xffff88823fffad90 of 8 bytes by task 6291 on cpu 0:
update_cached_migrate mm/compaction.c:473 [inline]
isolate_migratepages mm/compaction.c:2047 [inline]
compact_zone+0x1100/0x2720 mm/compaction.c:2508
compact_zone_order mm/compaction.c:2668 [inline]
try_to_compact_pages+0x39b/0x930 mm/compaction.c:2729
__alloc_pages_direct_compact+0x75/0x1f0 mm/page_alloc.c:3525
__alloc_pages_slowpath+0x232/0xd90 mm/page_alloc.c:4119
__alloc_pages+0x25d/0x340 mm/page_alloc.c:4581
alloc_pages_mpol+0xb1/0x1d0 mm/mempolicy.c:2133
alloc_pages+0xe0/0x100 mm/mempolicy.c:2204
__get_free_pages+0xc/0x30 mm/page_alloc.c:4615
io_mem_alloc io_uring/io_uring.c:2783 [inline]
io_allocate_scq_urings+0x119/0x360 io_uring/io_uring.c:3813
io_uring_create+0x537/0x920 io_uring/io_uring.c:4015
io_uring_setup io_uring/io_uring.c:4127 [inline]
__do_sys_io_uring_setup io_uring/io_uring.c:4154 [inline]
__se_sys_io_uring_setup+0x1ce/0x1e0 io_uring/io_uring.c:4148
__x64_sys_io_uring_setup+0x31/0x40 io_uring/io_uring.c:4148
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff88823fffad90 of 8 bytes by task 6292 on cpu 1:
update_cached_migrate mm/compaction.c:472 [inline]
isolate_migratepages mm/compaction.c:2047 [inline]
compact_zone+0x10db/0x2720 mm/compaction.c:2508
compact_zone_order mm/compaction.c:2668 [inline]
try_to_compact_pages+0x39b/0x930 mm/compaction.c:2729
__alloc_pages_direct_compact+0x75/0x1f0 mm/page_alloc.c:3525
__alloc_pages_slowpath+0x578/0xd90 mm/page_alloc.c:4202
__alloc_pages+0x25d/0x340 mm/page_alloc.c:4581
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
__kmalloc_large_node+0x80/0x120 mm/slab_common.c:1148
__do_kmalloc_node mm/slab_common.c:995 [inline]
__kmalloc_node+0xcc/0x1a0 mm/slab_common.c:1014
kmalloc_node include/linux/slab.h:620 [inline]
kvmalloc_node+0x72/0x160 mm/util.c:617
kvmalloc include/linux/slab.h:738 [inline]
kvmalloc_array include/linux/slab.h:756 [inline]
kvcalloc include/linux/slab.h:761 [inline]
cake_init+0x20e/0x5b0 net/sched/sch_cake.c:2738
qdisc_create+0x6b7/0xac0 net/sched/sch_api.c:1326
tc_modify_qdisc+0x653/0x1040 net/sched/sch_api.c:1747
rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6558
netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2545
rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6576
netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
netlink_unicast+0x589/0x650 net/netlink/af_netlink.c:1368
netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1910
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
____sys_sendmsg+0x37c/0x4d0 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmsg+0x1e9/0x270 net/socket.c:2667
__do_sys_sendmsg net/socket.c:2676 [inline]
__se_sys_sendmsg net/socket.c:2674 [inline]
__x64_sys_sendmsg+0x46/0x50 net/socket.c:2674
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000121200 -> 0x0000000000122600

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6292 Comm: syz-executor.3 Not tainted 6.7.0-rc3-syzkaller-00033-g3b47bc037bd4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.