Re: [moderation/CI] Re: mm/memcontrol: introduce per-tier memory accounting and control

#syz upstream

On Tue, Aug 18, 2026 at 5:46 AM syzbot ci
<[email protected]> wrote:
>
> syzbot ci has tested the following series
>
> [v1] mm/memcontrol: introduce per-tier memory accounting and control
> https://lore.kernel.org/all/[email protected]
> * [RFC PATCH 1/8] mm/memory-tiers: add node_to_tier_id and tier_id_to_nodemask
> * [RFC PATCH 2/8] mm/vmscan: add try_to_free_mem_cgroup_pages_nodemask
> * [RFC PATCH 3/8] mm/memcontrol: add per-tier page counter infrastructure and lifecycle
> * [RFC PATCH 4/8] mm/memcontrol: add per-tier charge and uncharge
> * [RFC PATCH 5/8] mm/memcontrol: add per-cpu stock for tier charge/uncharge
> * [RFC PATCH 6/8] mm/memcontrol: add memory.tier control file
> * [RFC PATCH 7/8] mm/memcontrol: auto-derive tier high/max from memory.high/max
> * [RFC PATCH 8/8] cgroup: add memory_tiered_limits cgroup mount option
>
> and found the following issue:
> WARNING in uncharge_folio
>
> Full report is available here:
> https://ci.syzbot.org/series/9db711d8-d389-45d1-b245-7e8b316a8432
>
> ***
>
> WARNING in uncharge_folio
>
> tree:      torvalds
> URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
> base:      dcacab904fe78d60840ba947a104993ee9ded887
> arch:      amd64
> compiler:  Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
> config:    https://ci.syzbot.org/builds/bf213e6f-1b40-41fa-a938-385807688eec/config
>
> ------------[ cut here ]------------
> debug_locks && !(rcu_read_lock_held() || lock_is_held(&(&cgroup_mutex)->dep_map))
> WARNING: ./include/linux/memcontrol.h:391 at uncharge_folio+0x459/0x5b0, CPU#1: udevd/5681
> Modules linked in:
> CPU: 1 UID: 0 PID: 5681 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> RIP: 0010:uncharge_folio+0x459/0x5b0
> Code: c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8b 3c 24 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d e9 88 79 00 00 90 <0f> 0b 90 e9 c9 fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 49 fc
> RSP: 0018:ffffc90004ff7210 EFLAGS: 00010246
> RAX: 0000000000000000 RBX: ffffc90004ff72a0 RCX: 0000000080000001
> RDX: 0000000000000000 RSI: ffffffff8e4a6d0d RDI: ffffffff8c4bb280
> RBP: ffffc90004ff72a8 R08: ffffea0006e7a7c7 R09: 1ffffd4000dcf4f8
> R10: dffffc0000000000 R11: fffff94000dcf4f9 R12: ffffea0006e7a7f8
> R13: 1ffffd4000dcf4f8 R14: 0000000000000001 R15: ffffea0006e7a7c0
> FS:  00007f1ec7ce0c80(0000) GS:ffff8882a8f6a000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f0cdf670000 CR3: 000000017358a000 CR4: 00000000000006f0
> Call Trace:
>  <TASK>
>  __mem_cgroup_uncharge_folios+0xfd/0x1d0
>  folio_batch_move_lru+0x86f/0xa60
>  lru_add_drain_cpu+0xbc/0x750
>  lru_add_drain+0x121/0x3e0
>  __folio_batch_release+0x48/0x90
>  shmem_undo_range+0x4e6/0x15d0
>  shmem_evict_inode+0x280/0xa80
>  evict+0x624/0xb50
>  dentry_kill+0x1b9/0x880
>  finish_dput+0x1a/0x260
>  filename_renameat2+0x61b/0x9a0
>  __se_sys_rename+0x55/0x2c0
>  do_syscall_64+0x174/0x580
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f1ec789a93b
> Code: 48 8b 15 f0 64 15 00 83 c8 ff 64 83 3a 15 75 0e 48 8b 7c 24 08 e8 d5 d4 07 00 f7 d8 19 c0 48 83 c4 18 c3 b8 52 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 be 64 15 00 f7 d8 64 89 02 48 83
> RSP: 002b:00007ffcb336cd08 EFLAGS: 00000202 ORIG_RAX: 0000000000000052
> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1ec789a93b
> RDX: 0000558c622ea032 RSI: 00007ffcb336cd28 RDI: 00007ffcb336d128
> RBP: 000055893abc0910 R08: 0000000000000006 R09: f80f8ce6f311cb22
> R10: 00000000000001b6 R11: 0000000000000202 R12: 000055893aba2730
> R13: 00007ffcb336cd28 R14: 00007ffcb336d128 R15: 0000558926efb160
>  </TASK>
>
>
> ***
>
> If these findings have caused you to resend the series or submit a
> separate fix, please add the following tag to your commit message:
>   Tested-by: [email protected]
>
> ---
> This report is generated by a bot. It may contain errors.
> syzbot ci engineers can be reached at [email protected].
>
> To test a fix for this bug, please reply with `#syz test`
> (on a separate line) and attach the patch to the email.
>
> Notes:
> - The patch will be applied on top of the tested series (as an
>   incremental fix).
> - To test a new version of the whole series, please send it directly
>   to [email protected].
> - Arguments like custom git repos and branches are not supported.
>
> The email will later be sent to:
> [[email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected]]
>
> If the report looks fine to you, reply with:
> #syz upstream
>
> If the report is a false positive, reply with
> #syz invalid
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-upstream-moderation" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> To view this discussion visit https://groups.google.com/d/msgid/syzkaller-upstream-moderation/6a83d5a2.4d75e56a.c9a88.0009.GAE%40google.com.