WARNING in max_vclocks_store

Status: upstream: reported on 2026/08/17 09:49
Reported-by: syzbot+9627ddf28c97f755f41d@syzkaller.appspotmail.com
First crash: 20d, last: 20d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in max_vclocks_store mm net -1 syz, C 3 372d 608d 29/29 fixed on 2025/10/29 21:02

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5883 at mm/page_alloc.c:4477 __alloc_pages+0x2e4/0x460 mm/page_alloc.c:4477
Modules linked in:
CPU: 0 PID: 5883 Comm: syz.0.9 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__alloc_pages+0x2e4/0x460 mm/page_alloc.c:4477
Code: 0c 25 28 00 00 00 48 3b 8c 24 a0 00 00 00 0f 85 9f 00 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 c6 05 88 0c a3 0c 01 <0f> 0b eb a4 a9 00 00 08 00 8b 74 24 0c 75 3e 44 89 f1 81 e1 7f ff
RSP: 0018:ffffc9000485fa20 EFLAGS: 00010246
RAX: ffffc9000485fa00 RBX: 1ffff9200090bf48 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000485fa88
RBP: ffffc9000485fb20 R08: ffffc9000485fa87 R09: 0000000000000000
R10: ffffc9000485fa60 R11: fffff5200090bf51 R12: 000000000000000b
R13: 0000000000000000 R14: 0000000000040dc0 R15: dffffc0000000000
FS:  00007f5ba457f6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c37d025 CR3: 000000002e6d1000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 alloc_pages_node include/linux/gfp.h:260 [inline]
 __kmalloc_large_node+0x8c/0x1f0 mm/slab_common.c:1148
 __do_kmalloc_node mm/slab_common.c:995 [inline]
 __kmalloc+0x114/0x240 mm/slab_common.c:1020
 kmalloc_array include/linux/slab.h:637 [inline]
 kcalloc include/linux/slab.h:668 [inline]
 max_vclocks_store+0x226/0x3f0 drivers/ptp/ptp_sysfs.c:297
 kernfs_fop_write_iter+0x3a4/0x520 fs/kernfs/file.c:352
 call_write_iter include/linux/fs.h:2018 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x474/0x9a0 fs/read_write.c:584
 ksys_write+0x151/0x260 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5ba379e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5ba457f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f5ba3a25fa0 RCX: 00007f5ba379e0d9
RDX: 0000000000000008 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007f5ba3835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ba3a26038 R14: 00007f5ba3a25fa0 R15: 00007ffeae4f3e28
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/17 09:51 linux-6.6.y d27334b2888c 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in max_vclocks_store
2026/08/17 09:48 linux-6.6.y d27334b2888c 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in max_vclocks_store
* Struck through repros no longer work on HEAD.