From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB380C433DF for ; Wed, 14 Oct 2020 12:02:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E2FF20848 for ; Wed, 14 Oct 2020 12:02:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729451AbgJNMCS (ORCPT ); Wed, 14 Oct 2020 08:02:18 -0400 Received: from mail-io1-f71.google.com ([209.85.166.71]:37364 "EHLO mail-io1-f71.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728627AbgJNMCS (ORCPT ); Wed, 14 Oct 2020 08:02:18 -0400 Received: by mail-io1-f71.google.com with SMTP id e21so2226729ioe.4 for ; Wed, 14 Oct 2020 05:02:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=PpanVSG5QtxgDny7I3jFKCGyv0HeDeutlW8J5GIIZ1c=; b=HtsOkbkCZtor7QFPvnBDrAPXf1VuD2HwW5t8LLYoSW6n426yDS6MKH0R9g4twhh/xe yZyc0sPqqC5C9ym9nPdWxe8OuoxLBC5uTjOwotbR8cPjIGqPIwcR7X98AAX3bc5rMEcp i5vdeGmFKk3EvlW0f58wiEtS/ah2F7KN7vzmhbrIRwne58FiNd8vsNVaYHpohyOxk3KR XQUhkJI5rI+BnMagVuybvAKCfARtMcfs/7wX/m0d5M2w9xvnLqo9/3a2Ia7+cWtKEMad p7IXxxa7w7npxpX7hLQZg/xAb3IZhmJ33CkMLgIwnYKOXkIOOOxTSVgWruKxH8dF/VtY AOSA== X-Gm-Message-State: AOAM530seldC3EphvxaQCh005nzSRBGXGwU4PUuSEockTY/MAdKMwpVX OzKEibs6O9w0oixd4v2WmjeLbI1QxcWeQNQqePtFhE2o3oJR X-Google-Smtp-Source: ABdhPJz924CB3e7OMG+B2tRssSKyjo4uJeq/05wULilZx+OJLSnePKSrqNhpRQg6GjleKxKiB4y5W6oLHNAYGzx3DIVudRtTB/9V MIME-Version: 1.0 X-Received: by 2002:a05:6e02:101:: with SMTP id t1mr3134383ilm.12.1602676936921; Wed, 14 Oct 2020 05:02:16 -0700 (PDT) Date: Wed, 14 Oct 2020 05:02:16 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000083d80105b1a04db2@google.com> Subject: possible deadlock in snd_pcm_period_elapsed From: syzbot To: alsa-devel@alsa-project.org, arnd@arndb.de, baolin.wang@linaro.org, linux-kernel@vger.kernel.org, paulhsia@chromium.org, perex@perex.cz, syzkaller-bugs@googlegroups.com, tiwai@suse.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: 029f56db Merge tag 'x86_asm_for_v5.10' of git://git.kernel.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1366d607900000 kernel config: https://syzkaller.appspot.com/x/.config?x=c5327fbeef7650a dashboard link: https://syzkaller.appspot.com/bug?extid=9e4ce89a893162de3148 compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9e4ce89a893162de3148@syzkaller.appspotmail.com ======================================================== WARNING: possible irq lock inversion dependency detected 5.9.0-syzkaller #0 Not tainted -------------------------------------------------------- swapper/0/0 just changed the state of lock: ffff88809a617108 (&group->lock){..-.}-{2:2}, at: snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 but this lock took another, SOFTIRQ-READ-unsafe lock in the past: (&card->ctl_files_rwlock){.+.+}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&card->ctl_files_rwlock); local_irq_disable(); lock(&group->lock); lock(&card->ctl_files_rwlock); lock(&group->lock); *** DEADLOCK *** 1 lock held by swapper/0/0: #0: ffffc90000007db0 ((&dpcm->timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline] #0: ffffc90000007db0 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0x57/0x160 kernel/time/timer.c:1405 the shortest dependencies between 2nd lock and 1st lock: -> (&card->ctl_files_rwlock){.+.+}-{2:2} { HARDIRQ-ON-R at: lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 __snd_ctl_add_replace+0x582/0x8a0 sound/core/control.c:382 snd_ctl_add_replace sound/core/control.c:399 [inline] snd_ctl_add+0x6e/0x110 sound/core/control.c:426 snd_card_dummy_new_mixer sound/drivers/dummy.c:885 [inline] snd_dummy_probe+0xb9e/0x1000 sound/drivers/dummy.c:1080 platform_drv_probe+0xcd/0x150 drivers/base/platform.c:747 really_probe+0x753/0x1110 drivers/base/dd.c:557 driver_probe_device+0x106/0x1a0 drivers/base/dd.c:738 bus_for_each_drv+0x108/0x170 drivers/base/bus.c:431 __device_attach+0x262/0x3f0 drivers/base/dd.c:912 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:491 device_add+0x1630/0x19b0 drivers/base/core.c:2926 platform_device_add+0x4ad/0x6e0 drivers/base/platform.c:597 platform_device_register_full+0x448/0x530 drivers/base/platform.c:720 platform_device_register_resndata include/linux/platform_device.h:131 [inline] platform_device_register_simple include/linux/platform_device.h:160 [inline] alsa_card_dummy_init+0x1b3/0x398 sound/drivers/dummy.c:1168 do_one_initcall+0x14b/0x350 init/main.c:1205 do_initcall_level+0x101/0x14c init/main.c:1278 do_initcalls+0x59/0x9b init/main.c:1294 kernel_init_freeable+0x356/0x474 init/main.c:1514 kernel_init+0xd/0x290 init/main.c:1403 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 SOFTIRQ-ON-R at: lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 __snd_ctl_add_replace+0x582/0x8a0 sound/core/control.c:382 snd_ctl_add_replace sound/core/control.c:399 [inline] snd_ctl_add+0x6e/0x110 sound/core/control.c:426 snd_card_dummy_new_mixer sound/drivers/dummy.c:885 [inline] snd_dummy_probe+0xb9e/0x1000 sound/drivers/dummy.c:1080 platform_drv_probe+0xcd/0x150 drivers/base/platform.c:747 really_probe+0x753/0x1110 drivers/base/dd.c:557 driver_probe_device+0x106/0x1a0 drivers/base/dd.c:738 bus_for_each_drv+0x108/0x170 drivers/base/bus.c:431 __device_attach+0x262/0x3f0 drivers/base/dd.c:912 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:491 device_add+0x1630/0x19b0 drivers/base/core.c:2926 platform_device_add+0x4ad/0x6e0 drivers/base/platform.c:597 platform_device_register_full+0x448/0x530 drivers/base/platform.c:720 platform_device_register_resndata include/linux/platform_device.h:131 [inline] platform_device_register_simple include/linux/platform_device.h:160 [inline] alsa_card_dummy_init+0x1b3/0x398 sound/drivers/dummy.c:1168 do_one_initcall+0x14b/0x350 init/main.c:1205 do_initcall_level+0x101/0x14c init/main.c:1278 do_initcalls+0x59/0x9b init/main.c:1294 kernel_init_freeable+0x356/0x474 init/main.c:1514 kernel_init+0xd/0x290 init/main.c:1403 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 INITIAL READ USE at: lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 __snd_ctl_add_replace+0x582/0x8a0 sound/core/control.c:382 snd_ctl_add_replace sound/core/control.c:399 [inline] snd_ctl_add+0x6e/0x110 sound/core/control.c:426 snd_card_dummy_new_mixer sound/drivers/dummy.c:885 [inline] snd_dummy_probe+0xb9e/0x1000 sound/drivers/dummy.c:1080 platform_drv_probe+0xcd/0x150 drivers/base/platform.c:747 really_probe+0x753/0x1110 drivers/base/dd.c:557 driver_probe_device+0x106/0x1a0 drivers/base/dd.c:738 bus_for_each_drv+0x108/0x170 drivers/base/bus.c:431 __device_attach+0x262/0x3f0 drivers/base/dd.c:912 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:491 device_add+0x1630/0x19b0 drivers/base/core.c:2926 platform_device_add+0x4ad/0x6e0 drivers/base/platform.c:597 platform_device_register_full+0x448/0x530 drivers/base/platform.c:720 platform_device_register_resndata include/linux/platform_device.h:131 [inline] platform_device_register_simple include/linux/platform_device.h:160 [inline] alsa_card_dummy_init+0x1b3/0x398 sound/drivers/dummy.c:1168 do_one_initcall+0x14b/0x350 init/main.c:1205 do_initcall_level+0x101/0x14c init/main.c:1278 do_initcalls+0x59/0x9b init/main.c:1294 kernel_init_freeable+0x356/0x474 init/main.c:1514 kernel_init+0xd/0x290 init/main.c:1403 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 } ... key at: [] snd_card_new.__key.3+0x0/0x10 ... acquired at: lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 loopback_check_format sound/drivers/aloop.c:358 [inline] loopback_trigger+0xc40/0x1500 sound/drivers/aloop.c:387 snd_pcm_do_start sound/core/pcm_native.c:1350 [inline] snd_pcm_action_single sound/core/pcm_native.c:1207 [inline] snd_pcm_action sound/core/pcm_native.c:1290 [inline] snd_pcm_start+0x471/0x6c0 sound/core/pcm_native.c:1391 __snd_pcm_lib_xfer+0xf73/0x1320 sound/core/pcm_lib.c:2247 snd_pcm_oss_write3+0x209/0x330 sound/core/oss/pcm_oss.c:1221 snd_pcm_plug_write_transfer+0x28b/0x490 sound/core/oss/pcm_plugin.c:624 snd_pcm_oss_write2+0x156/0x370 sound/core/oss/pcm_oss.c:1353 snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1419 [inline] snd_pcm_oss_write+0x911/0xd70 sound/core/oss/pcm_oss.c:2765 vfs_write+0x2dd/0xd20 fs/read_write.c:584 ksys_write+0x11b/0x220 fs/read_write.c:639 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> (&group->lock){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xaa/0xd0 kernel/locking/spinlock.c:159 snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 call_timer_fn+0x91/0x160 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers+0x65e/0x830 kernel/time/timer.c:1757 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1770 __do_softirq+0x256/0x6e0 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9a/0xf0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu+0x21f/0x230 kernel/softirq.c:423 irq_exit_rcu+0x5/0x20 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0xe0/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] acpi_idle_do_entry+0xde/0x2d0 drivers/acpi/processor_idle.c:517 acpi_idle_enter+0x2fa/0x440 drivers/acpi/processor_idle.c:648 cpuidle_enter_state+0x38a/0x980 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:350 call_cpuidle kernel/sched/idle.c:132 [inline] cpuidle_idle_call kernel/sched/idle.c:213 [inline] do_idle+0x4a7/0x650 kernel/sched/idle.c:273 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369 start_kernel+0x4b0/0x57c init/main.c:1049 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 INITIAL USE at: lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0xa6/0xc0 kernel/locking/spinlock.c:167 spin_lock_irq include/linux/spinlock.h:379 [inline] snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] snd_pcm_hw_params+0xca/0x16b0 sound/core/pcm_native.c:672 snd_pcm_oss_change_params_locked+0x25e0/0x4410 sound/core/oss/pcm_oss.c:941 snd_pcm_oss_make_ready_locked sound/core/oss/pcm_oss.c:1166 [inline] snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1384 [inline] snd_pcm_oss_write+0x269/0xd70 sound/core/oss/pcm_oss.c:2765 vfs_write+0x2dd/0xd20 fs/read_write.c:584 ksys_write+0x11b/0x220 fs/read_write.c:639 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 } ... key at: [] snd_pcm_group_init.__key+0x0/0x10 ... acquired at: mark_usage kernel/locking/lockdep.c:4305 [inline] __lock_acquire+0xa67/0x2bd0 kernel/locking/lockdep.c:4791 lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xaa/0xd0 kernel/locking/spinlock.c:159 snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 call_timer_fn+0x91/0x160 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers+0x65e/0x830 kernel/time/timer.c:1757 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1770 __do_softirq+0x256/0x6e0 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9a/0xf0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu+0x21f/0x230 kernel/softirq.c:423 irq_exit_rcu+0x5/0x20 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0xe0/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] acpi_idle_do_entry+0xde/0x2d0 drivers/acpi/processor_idle.c:517 acpi_idle_enter+0x2fa/0x440 drivers/acpi/processor_idle.c:648 cpuidle_enter_state+0x38a/0x980 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:350 call_cpuidle kernel/sched/idle.c:132 [inline] cpuidle_idle_call kernel/sched/idle.c:213 [inline] do_idle+0x4a7/0x650 kernel/sched/idle.c:273 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369 start_kernel+0x4b0/0x57c init/main.c:1049 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.9.0-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+0x1d6/0x29e lib/dump_stack.c:118 print_irq_inversion_bug+0xa5c/0xd70 kernel/locking/lockdep.c:3817 check_usage_forwards kernel/locking/lockdep.c:191 [inline] mark_lock_irq kernel/locking/lockdep.c:3980 [inline] mark_lock+0xe80/0x2050 kernel/locking/lockdep.c:4408 mark_usage kernel/locking/lockdep.c:4305 [inline] __lock_acquire+0xa67/0x2bd0 kernel/locking/lockdep.c:4791 lock_acquire+0x160/0x710 kernel/locking/lockdep.c:5442 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xaa/0xd0 kernel/locking/spinlock.c:159 snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 call_timer_fn+0x91/0x160 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers+0x65e/0x830 kernel/time/timer.c:1757 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1770 __do_softirq+0x256/0x6e0 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9a/0xf0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu+0x21f/0x230 kernel/softirq.c:423 irq_exit_rcu+0x5/0x20 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0xe0/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61 Code: 80 e1 07 80 c1 03 38 c1 7c bc 48 89 df e8 0a 4e 60 f9 eb b2 cc cc cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d f6 6a 4d 00 fb f4 90 e9 07 00 00 00 0f 00 2d e6 6a 4d 00 f4 c3 cc cc 41 56 53 65 RSP: 0018:ffffffff89807d68 EFLAGS: 00000282 RAX: 1ffffffff131a5c7 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff817b4020 R09: fffffbfff1312d39 R10: fffffbfff1312d39 R11: 0000000000000000 R12: ffff8880a6732864 R13: ffff8880a3185804 R14: ffff8880a6732864 R15: dffffc0000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline] acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline] acpi_idle_do_entry+0xde/0x2d0 drivers/acpi/processor_idle.c:517 acpi_idle_enter+0x2fa/0x440 drivers/acpi/processor_idle.c:648 cpuidle_enter_state+0x38a/0x980 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:350 call_cpuidle kernel/sched/idle.c:132 [inline] cpuidle_idle_call kernel/sched/idle.c:213 [inline] do_idle+0x4a7/0x650 kernel/sched/idle.c:273 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369 start_kernel+0x4b0/0x57c init/main.c:1049 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 --- This report is generated by a bot. 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