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[209.132.180.67]) by mx.google.com with ESMTP id r13si178085otq.279.2020.03.03.17.03.44; Tue, 03 Mar 2020 17:03:57 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387432AbgCDBD2 (ORCPT + 99 others); Tue, 3 Mar 2020 20:03:28 -0500 Received: from hua.moonlit-rail.com ([45.79.167.250]:39914 "EHLO hua.moonlit-rail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387411AbgCDBD1 (ORCPT ); Tue, 3 Mar 2020 20:03:27 -0500 Received: from 209-6-248-230.s2276.c3-0.wrx-ubr1.sbo-wrx.ma.cable.rcncustomer.com ([209.6.248.230] helo=boston.moonlit-rail.com) by hua.moonlit-rail.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1j9IRZ-0005Dy-Rb for linux-kernel@vger.kernel.org; Tue, 03 Mar 2020 20:03:25 -0500 Received: from springdale.moonlit-rail.com ([192.168.71.35]) by boston.moonlit-rail.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1j9IRZ-0008St-EJ for linux-kernel@vger.kernel.org; Tue, 03 Mar 2020 20:03:25 -0500 Subject: Re: Linux 5.5.7 To: Linux Kernel References: <20200301093749.GA1013956@kroah.com> From: Kris Karas Message-ID: <6d4f9ac8-a478-2ae4-0fe3-5d074d267148@moonlit-rail.com> Date: Tue, 3 Mar 2020 20:03:25 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200301093749.GA1013956@kroah.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Greg KH wrote: > I'm announcing the release of the 5.5.7 kernel. > All users of the 5.5 kernel series must upgrade. This one gave me an OOPS on boot, necessitating an Alt-SysRq-E to get in and save at least a portion of it to disk.? There are actually several OOPSen in the dmesg output I'll append, only common theme I can see being buggery within an IRQ handler. Not seeing any similar reports as a reply to the 5.5.7 announcement, I was all set to bisect.? But reproducing this is elusive; I've only got one hit thus far, on the second of 8 or so boots.? (Hardware is a very stable Ryzen 2700 machine with ECC memory.)? Thus, this could have been introduced in 5.5.6 or even earlier. In any case, I have seen a few patches recently mentioning NMI/IRQ work; perhaps one of those patch authors will recognize the stack traces and offer a clue. Best, Kris Karas BUG: kernel NULL pointer dereference, address: 00000000000000e8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 7f6a50067 P4D 7f6a50067 PUD 7f6a51067 PMD 0 Oops: 0000 [#1] SMP CPU: 3 PID: 516 Comm: pidof Not tainted 5.5.7 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X470 Taichi, BIOS P3.50 07/18/2019 RIP: 0010:cap_capable+0x13/0x70 Code: bf f4 ff ff ff 66 90 e9 01 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 4c 8b 87 88 00 00 00 4c 39 c6 74 39 45 8b 88 e8 00 00 00 <44> 39 8e e8 00 00 00 7e 18 48 8b 86 e0 00 00 00 4c 39 c0 74 12 48 RSP: 0018:ffffc90000777cb0 EFLAGS: 00010207 RAX: ffff8887f96ea000 RBX: 0000000000000002 RCX: 0000000000000002 RDX: 0000000000000013 RSI: 0000000000000000 RDI: ffff8887f9646480 RBP: 0000000000000013 R08: ffffffff82423da0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8887f9646480 R14: ffffffff822a7620 R15: ffff8887fae600c0 FS: 00007f8ee26cd740(0000) GS:ffff8887fecc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000e8 CR3: 00000007f8691000 CR4: 00000000003406e0 Call Trace: security_capable+0x36/0x50 ptrace_has_cap+0x14/0x30 __ptrace_may_access+0x76/0x110 ptrace_may_access+0x28/0x50 do_task_stat+0x7b/0xd90 ? do_filp_open+0xab/0x100 proc_single_show+0x54/0xc0 ? __kmalloc+0x183/0x210 seq_read+0xbb/0x3c0 vfs_read+0xc6/0x150 ksys_read+0x6b/0x100 do_syscall_64+0x3d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f8ee27d682e Code: c0 e9 f6 fe ff ff 50 48 8d 3d b6 5d 0a 00 e8 e9 fd 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007ffdc7fdcf58 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f8ee28ce958 RCX: 00007f8ee27d682e RDX: 0000000000000400 RSI: 00000000017e2590 RDI: 0000000000000004 RBP: 00007f8ee28ce950 R08: 00007f8ee28ac120 R09: 00007ffdc7fdce00 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdc7fddf02 Modules linked in: CR2: 00000000000000e8 ---[ end trace 9da0e81512fbb929 ]--- RIP: 0010:cap_capable+0x13/0x70 Code: bf f4 ff ff ff 66 90 e9 01 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 4c 8b 87 88 00 00 00 4c 39 c6 74 39 45 8b 88 e8 00 00 00 <44> 39 8e e8 00 00 00 7e 18 48 8b 86 e0 00 00 00 4c 39 c0 74 12 48 RSP: 0018:ffffc90000777cb0 EFLAGS: 00010207 RAX: ffff8887f96ea000 RBX: 0000000000000002 RCX: 0000000000000002 RDX: 0000000000000013 RSI: 0000000000000000 RDI: ffff8887f9646480 RBP: 0000000000000013 R08: ffffffff82423da0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8887f9646480 R14: ffffffff822a7620 R15: ffff8887fae600c0 FS: 00007f8ee26cd740(0000) GS:ffff8887fecc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000e8 CR3: 00000007f8691000 CR4: 00000000003406e0 udevd[518]: starting eudev-3.2.9 rcu: INFO: rcu_sched self-detected stall on CPU rcu: 14-....: (20999 ticks this GP) idle=216/1/0x4000000000000002 softirq=454/454 fqs=5250 (t=21004 jiffies g=-755 q=1327) NMI backtrace for cpu 14 CPU: 14 PID: 520 Comm: pidof Tainted: G D 5.5.7 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X470 Taichi, BIOS P3.50 07/18/2019 Call Trace: dump_stack+0x50/0x70 nmi_cpu_backtrace.cold+0x14/0x53 ? lapic_can_unplug_cpu.cold+0x44/0x44 nmi_trigger_cpumask_backtrace+0x7b/0x88 rcu_dump_cpu_stacks+0x7b/0xa9 rcu_sched_clock_irq.cold+0x152/0x39b update_process_times+0x1f/0x50 tick_sched_timer+0x40/0x90 ? tick_sched_do_timer+0x50/0x50 __hrtimer_run_queues+0xdd/0x180 hrtimer_interrupt+0x108/0x230 smp_apic_timer_interrupt+0x53/0xa0 apic_timer_interrupt+0xf/0x20 RIP: 0010:queued_spin_lock_slowpath+0x41/0x1a0 Code: 2f 08 0f 92 c0 0f b6 c0 c1 e0 08 89 c2 8b 07 30 e4 09 d0 a9 00 01 ff ff 75 18 85 c0 74 0e 8b 07 84 c0 74 08 f3 90 8b 07 84 c0 <75> f8 66 c7 07 01 00 c3 f6 c4 01 75 04 c6 47 01 00 48 c7 c0 40 29 RSP: 0018:ffffc90001e87d08 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000101 RBX: ffff8887f96f0000 RCX: ffff8887f96f0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8887f96f0658 RBP: 000000000000000d R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8887f50b7080 R13: ffffffff82424480 R14: ffffffff82424480 R15: ffff8887f50b70c0 ptrace_may_access+0x1e/0x50 do_task_stat+0x7b/0xd90 ? do_filp_open+0xab/0x100 proc_single_show+0x54/0xc0 ? __kmalloc+0x183/0x210 seq_read+0xbb/0x3c0 vfs_read+0xc6/0x150 ksys_read+0x6b/0x100 do_syscall_64+0x3d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f666796082e Code: c0 e9 f6 fe ff ff 50 48 8d 3d b6 5d 0a 00 e8 e9 fd 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007ffe26688b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6667a58958 RCX: 00007f666796082e RDX: 0000000000000400 RSI: 000000000153e590 RDI: 0000000000000004 RBP: 00007f6667a58950 R08: 00007f6667a36120 R09: 00007ffe266889e0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe2668aee9 ... sysrq: Terminate All Tasks rcu: INFO: rcu_sched self-detected stall on CPU rcu: 14-....: (83876 ticks this GP) idle=216/1/0x4000000000000002 softirq=454/454 fqs=20970 (t=84003 jiffies g=-755 q=2695) NMI backtrace for cpu 14 CPU: 14 PID: 520 Comm: pidof Tainted: G D 5.5.7 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X470 Taichi, BIOS P3.50 07/18/2019 Call Trace: dump_stack+0x50/0x70 nmi_cpu_backtrace.cold+0x14/0x53 ? lapic_can_unplug_cpu.cold+0x44/0x44 nmi_trigger_cpumask_backtrace+0x7b/0x88 rcu_dump_cpu_stacks+0x7b/0xa9 rcu_sched_clock_irq.cold+0x152/0x39b update_process_times+0x1f/0x50 tick_sched_timer+0x40/0x90 ? tick_sched_do_timer+0x50/0x50 __hrtimer_run_queues+0xdd/0x180 hrtimer_interrupt+0x108/0x230 smp_apic_timer_interrupt+0x53/0xa0 apic_timer_interrupt+0xf/0x20 RIP: 0010:queued_spin_lock_slowpath+0x3d/0x1a0 Code: 3e f0 0f ba 2f 08 0f 92 c0 0f b6 c0 c1 e0 08 89 c2 8b 07 30 e4 09 d0 a9 00 01 ff ff 75 18 85 c0 74 0e 8b 07 84 c0 74 08 f3 90 <8b> 07 84 c0 75 f8 66 c7 07 01 00 c3 f6 c4 01 75 04 c6 47 01 00 48 RSP: 0018:ffffc90001e87d08 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000101 RBX: ffff8887f96f0000 RCX: ffff8887f96f0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8887f96f0658 RBP: 000000000000000d R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8887f50b7080 R13: ffffffff82424480 R14: ffffffff82424480 R15: ffff8887f50b70c0 ptrace_may_access+0x1e/0x50 do_task_stat+0x7b/0xd90 ? do_filp_open+0xab/0x100 proc_single_show+0x54/0xc0 ? __kmalloc+0x183/0x210 seq_read+0xbb/0x3c0 vfs_read+0xc6/0x150 ksys_read+0x6b/0x100 do_syscall_64+0x3d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f666796082e Code: c0 e9 f6 fe ff ff 50 48 8d 3d b6 5d 0a 00 e8 e9 fd 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007ffe26688b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6667a58958 RCX: 00007f666796082e RDX: 0000000000000400 RSI: 000000000153e590 RDI: 0000000000000004 RBP: 00007f6667a58950 R08: 00007f6667a36120 R09: 00007ffe266889e0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe2668aee9 rcu: INFO: rcu_sched detected expedited stalls on CPUs/tasks: { 14-... } 21041 jiffies s: 45 root: 0x4000/. rcu: blocking rcu_node structures: Task dump for CPU 14: pidof R running task 0 520 1 0x8000000c Call Trace: ? do_syscall_64+0x3d/0x120 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 rcu: INFO: rcu_sched self-detected stall on CPU rcu: 14-....: (146878 ticks this GP) idle=216/1/0x4000000000000002 softirq=454/454 fqs=36715 (t=147006 jiffies g=-755 q=3376) NMI backtrace for cpu 14 CPU: 14 PID: 520 Comm: pidof Tainted: G D 5.5.7 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X470 Taichi, BIOS P3.50 07/18/2019 Call Trace: dump_stack+0x50/0x70 nmi_cpu_backtrace.cold+0x14/0x53 ? lapic_can_unplug_cpu.cold+0x44/0x44 nmi_trigger_cpumask_backtrace+0x7b/0x88 rcu_dump_cpu_stacks+0x7b/0xa9 rcu_sched_clock_irq.cold+0x152/0x39b update_process_times+0x1f/0x50 tick_sched_timer+0x40/0x90 ? tick_sched_do_timer+0x50/0x50 __hrtimer_run_queues+0xdd/0x180 hrtimer_interrupt+0x108/0x230 smp_apic_timer_interrupt+0x53/0xa0 apic_timer_interrupt+0xf/0x20 RIP: 0010:queued_spin_lock_slowpath+0x3d/0x1a0 Code: 3e f0 0f ba 2f 08 0f 92 c0 0f b6 c0 c1 e0 08 89 c2 8b 07 30 e4 09 d0 a9 00 01 ff ff 75 18 85 c0 74 0e 8b 07 84 c0 74 08 f3 90 <8b> 07 84 c0 75 f8 66 c7 07 01 00 c3 f6 c4 01 75 04 c6 47 01 00 48 RSP: 0018:ffffc90001e87d08 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000101 RBX: ffff8887f96f0000 RCX: ffff8887f96f0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8887f96f0658 RBP: 000000000000000d R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8887f50b7080 R13: ffffffff82424480 R14: ffffffff82424480 R15: ffff8887f50b70c0 ptrace_may_access+0x1e/0x50 do_task_stat+0x7b/0xd90 ? do_filp_open+0xab/0x100 proc_single_show+0x54/0xc0 ? __kmalloc+0x183/0x210 seq_read+0xbb/0x3c0 vfs_read+0xc6/0x150 ksys_read+0x6b/0x100 do_syscall_64+0x3d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f666796082e Code: c0 e9 f6 fe ff ff 50 48 8d 3d b6 5d 0a 00 e8 e9 fd 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007ffe26688b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6667a58958 RCX: 00007f666796082e RDX: 0000000000000400 RSI: 000000000153e590 RDI: 0000000000000004 RBP: 00007f6667a58950 R08: 00007f6667a36120 R09: 00007ffe266889e0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe2668aee9 rcu: INFO: rcu_sched detected expedited stalls on CPUs/tasks: { 14-... } 85041 jiffies s: 45 root: 0x4000/. rcu: blocking rcu_node structures: Task dump for CPU 14: pidof R running task 0 520 1 0x8000000c Call Trace: ? do_syscall_64+0x3d/0x120 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 rcu: INFO: rcu_sched self-detected stall on CPU rcu: 14-....: (209792 ticks this GP) idle=216/1/0x4000000000000002 softirq=454/454 fqs=52439 (t=210009 jiffies g=-755 q=3747) NMI backtrace for cpu 14 CPU: 14 PID: 520 Comm: pidof Tainted: G D 5.5.7 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X470 Taichi, BIOS P3.50 07/18/2019 Call Trace: dump_stack+0x50/0x70 nmi_cpu_backtrace.cold+0x14/0x53 ? lapic_can_unplug_cpu.cold+0x44/0x44 nmi_trigger_cpumask_backtrace+0x7b/0x88 rcu_dump_cpu_stacks+0x7b/0xa9 rcu_sched_clock_irq.cold+0x152/0x39b update_process_times+0x1f/0x50 tick_sched_timer+0x40/0x90 ? tick_sched_do_timer+0x50/0x50 __hrtimer_run_queues+0xdd/0x180 hrtimer_interrupt+0x108/0x230 smp_apic_timer_interrupt+0x53/0xa0 apic_timer_interrupt+0xf/0x20 RIP: 0010:queued_spin_lock_slowpath+0x3d/0x1a0 Code: 3e f0 0f ba 2f 08 0f 92 c0 0f b6 c0 c1 e0 08 89 c2 8b 07 30 e4 09 d0 a9 00 01 ff ff 75 18 85 c0 74 0e 8b 07 84 c0 74 08 f3 90 <8b> 07 84 c0 75 f8 66 c7 07 01 00 c3 f6 c4 01 75 04 c6 47 01 00 48 RSP: 0018:ffffc90001e87d08 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000101 RBX: ffff8887f96f0000 RCX: ffff8887f96f0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8887f96f0658 RBP: 000000000000000d R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8887f50b7080 R13: ffffffff82424480 R14: ffffffff82424480 R15: ffff8887f50b70c0 ptrace_may_access+0x1e/0x50 do_task_stat+0x7b/0xd90 ? do_filp_open+0xab/0x100 proc_single_show+0x54/0xc0 ? __kmalloc+0x183/0x210 seq_read+0xbb/0x3c0 vfs_read+0xc6/0x150 ksys_read+0x6b/0x100 do_syscall_64+0x3d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f666796082e Code: c0 e9 f6 fe ff ff 50 48 8d 3d b6 5d 0a 00 e8 e9 fd 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007ffe26688b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f6667a58958 RCX: 00007f666796082e RDX: 0000000000000400 RSI: 000000000153e590 RDI: 0000000000000004 RBP: 00007f6667a58950 R08: 00007f6667a36120 R09: 00007ffe266889e0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe2668aee9 rcu: INFO: rcu_sched detected expedited stalls on CPUs/tasks: { 14-... } 150577 jiffies s: 45 root: 0x4000/. rcu: blocking rcu_node structures: Task dump for CPU 14: pidof R running task 0 520 1 0x8000000c Call Trace: ? do_syscall_64+0x3d/0x120 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9