On Thu 13-08-20 12:44:16, Michal Hocko wrote: > This smells like 3e38e0aaca9e ("mm: memcg: charge memcg percpu memory to > the parent cgroup"). This should be addressed by http://lkml.kernel.org/r/20200813152033.GA701678@xxxxxxxxxxx I haven't noticed this is panic_on_warn earlier. > On Thu 13-08-20 02:47:26, syzbot wrote: > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: dc06fe51 Merge tag 'rtc-5.9' of git://git.kernel.org/pub/s.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=12d34bd6900000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=9c89856ae5fc8b6 > > dashboard link: https://syzkaller.appspot.com/bug?extid=35d35ef677516d65bdda > > compiler: gcc (GCC) 10.1.0-syz 20200507 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+35d35ef677516d65bdda@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > mem auto-init: stack:off, heap alloc:on, heap free:off > > Memory: 6461180K/7863916K available (116743K kernel code, 17665K rwdata, 21624K rodata, 2792K init, 23940K bss, 1402480K reserved, 0K cma-reserved) > > Running RCU self tests > > rcu: Preemptible hierarchical RCU implementation. > > rcu: RCU lockdep checking is enabled. > > rcu: RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=2. > > rcu: RCU callback double-/use-after-free debug enabled. > > rcu: RCU debug extended QS entry/exit. > > All grace periods are expedited (rcu_expedited). > > Trampoline variant of Tasks RCU enabled. > > rcu: RCU calculated value of scheduler-enlistment delay is 10 jiffies. > > rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=2 > > NR_IRQS: 4352, nr_irqs: 440, preallocated irqs: 16 > > random: get_random_bytes called from boot_init_stack_canary arch/x86/include/asm/stackprotector.h:80 [inline] with crng_init=0 > > random: get_random_bytes called from start_kernel+0x23b/0x46a init/main.c:957 with crng_init=0 > > Console: colour VGA+ 80x25 > > printk: console [ttyS0] enabled > > printk: console [ttyS0] enabled > > printk: bootconsole [earlyser0] disabled > > printk: bootconsole [earlyser0] disabled > > Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar > > ... MAX_LOCKDEP_SUBCLASSES: 8 > > ... MAX_LOCK_DEPTH: 48 > > ... MAX_LOCKDEP_KEYS: 8192 > > ... CLASSHASH_SIZE: 4096 > > ... MAX_LOCKDEP_ENTRIES: 32768 > > ... MAX_LOCKDEP_CHAINS: 65536 > > ... CHAINHASH_SIZE: 32768 > > memory used by lock dependency info: 6301 kB > > memory used for stack traces: 4224 kB > > per task-struct memory footprint: 1920 bytes > > mempolicy: Enabling automatic NUMA balancing. Configure with numa_balancing= or the kernel.numa_balancing sysctl > > ACPI: Core revision 20200717 > > APIC: Switch to symmetric I/O mode setup > > x2apic enabled > > Switched APIC routing to physical x2apic. > > ..TIMER: vector=0x30 apic1=0 pin1=0 apic2=-1 pin2=-1 > > clocksource: tsc-early: mask: 0xffffffffffffffff max_cycles: 0x212735223b2, max_idle_ns: 440795277976 ns > > Calibrating delay loop (skipped) preset value.. 4600.00 BogoMIPS (lpj=23000000) > > pid_max: default: 32768 minimum: 301 > > LSM: Security Framework initializing > > LSM: security= is ignored because it is superseded by lsm= > > Yama: becoming mindful. > > TOMOYO Linux initialized > > AppArmor: AppArmor initialized > > LSM support for eBPF active > > Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes, vmalloc) > > Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes, vmalloc) > > Mount-cache hash table entries: 16384 (order: 5, 131072 bytes, vmalloc) > > Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes, vmalloc) > > ------------[ cut here ]------------ > > WARNING: CPU: 0 PID: 0 at mm/memcontrol.c:5226 memalloc_unuse_memcg include/linux/sched/mm.h:331 [inline] > > WARNING: CPU: 0 PID: 0 at mm/memcontrol.c:5226 mem_cgroup_css_alloc+0x535/0x1c30 mm/memcontrol.c:5285 > > Kernel panic - not syncing: panic_on_warn set ... > > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.8.0-syzkaller #0 > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > Call Trace: > > __dump_stack lib/dump_stack.c:77 [inline] > > dump_stack+0x18f/0x20d lib/dump_stack.c:118 > > panic+0x2e3/0x75c kernel/panic.c:231 > > __warn.cold+0x20/0x4a kernel/panic.c:600 > > report_bug+0x1bd/0x210 lib/bug.c:198 > > handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234 > > exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254 > > asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536 > > RIP: 0010:mem_cgroup_alloc mm/memcontrol.c:5226 [inline] > > RIP: 0010:mem_cgroup_css_alloc+0x535/0x1c30 mm/memcontrol.c:5284 > > Code: 01 00 48 8d bb 28 14 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 74 81 e8 e0 00 c2 f9 e9 77 ff ff ff <0f> 0b e9 21 fc ff ff 48 89 ef e8 bc 28 c7 f9 48 b8 00 00 00 00 00 > > RSP: 0000:ffffffff89a07e20 EFLAGS: 00010246 > > RAX: dffffc0000000000 RBX: ffffffff89a99dc0 RCX: 1ffff110152b2028 > > RDX: 1ffffffff135363d RSI: ffffffff83b0f2c2 RDI: ffffffff89a9b1e8 > > RBP: ffff8880a9590000 R08: 0000000000000001 R09: ffff88821b801aef > > R10: 0000000000000000 R11: ffffffff810000d4 R12: ffffffff8ab224b4 > > R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff8ab224d0 > > cgroup_init_subsys+0x215/0x4d7 kernel/cgroup/cgroup.c:5587 > > cgroup_init+0x359/0xa63 kernel/cgroup/cgroup.c:5713 > > start_kernel+0x426/0x46a init/main.c:1035 > > secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 > > Rebooting in 86400 seconds.. > > > > > > --- > > 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 syzkaller@xxxxxxxxxxxxxxxx. > > > > syzbot will keep track of this issue. See: > > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > -- > Michal Hocko > SUSE Labs -- Michal Hocko SUSE Labs