From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f197.google.com (mail-il1-f197.google.com [209.85.166.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CD4E22C6BB for ; Fri, 16 Aug 2024 05:50:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723787423; cv=none; b=jVwVCT6zSZrmJgviYEBTAEGQObHky/ceIt3vVl9HQJrg3EPQdB8bn1qwDTELBJluLhx5ldE1Lph72WCJMsKBErYtVyv07irsLOpRpIVlvHkzDO9Eq0ruqtDNxw/znXpAXj9kG01l01K05w5Lp59vRlJdvh4s9ATYq6yhrwp7MYo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723787423; c=relaxed/simple; bh=NlyeKC98G07ZlP3JtbyLpS66PuDKj7yfqVE4C+kSgq8=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=dL50h58+C+JDhbnHJaaBf1BDNlvxFsPK0KOEwmCkq9QAVbAa1hbyYqGgcIyB3CEIvIFOPRVqnh4msWh/2LV28xnpLtPfJDpnc45dqDN11Jq7u15Mosrmz0EwyIRjgvt89tawpQFWiCzgpSVh0nAOULZacUGnWynEPRW4717HxL0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f197.google.com with SMTP id e9e14a558f8ab-39b3dc8cdcbso19200735ab.2 for ; Thu, 15 Aug 2024 22:50:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723787421; x=1724392221; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=bsRx3+LRntTKS6uYKzXbggn0dk4hpH/2iuhIfPVYhd4=; b=q0l8/ySMqwjT+IiDka55EGMkhFZ8/LmR4p2rooDMOpLZg2h0JJRYrLXkfYIN3OnW4n i+LnAaQaL4jJQ2fxfC1e8W+ZhtnCvR+9OAMLld8quBY0rzsRjM0iY8C+MtTsWssN3frc aH8PKbpA2NMJqnXdvlgwHOEPQrF+gQa6xem3VVxX/NRX3+OYCETMxpcS3vVJkDDSUVju hczdNcXWidHsReTeV32tjXsegMuMGHp+K0NJsZAabX6cWcDjHR/W3iojV79QSuojanIM JBD9TZWfygaX/ii7OEPMj5gQO3C+/AVuhCN0umFnGqKvp/6zKUGFEKv8JlrCTu49b4A6 5iIw== X-Gm-Message-State: AOJu0Yzedv8AWuMTNRHiUn2L689G5Fyrdk7trkA3P2ZY3Ftm9ulk5vll h+ctWrmMuRfjfmW+EpjO5LgAISJvOlhcmqOH8/qLmKoOKUmlr9Q0/hzp5AhO1YGYfyiCz4wxMbG J1TSwOJrTILJdQqiKMTI/oHapSEY6esxzZ3U8IssuuyqNH01dN9boi1s= X-Google-Smtp-Source: AGHT+IGivPBrGdxOdfD1RLlszJrbZlQ1c7663DoJLPrBeUlwu4yqAV9nRh+l8e36WllT15AZlDSihero5fycQ4ggNv3K4YUsvnCG Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1d0a:b0:39a:e909:29f6 with SMTP id e9e14a558f8ab-39d26c343c3mr1675475ab.0.1723787420970; Thu, 15 Aug 2024 22:50:20 -0700 (PDT) Date: Thu, 15 Aug 2024 22:50:20 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000e540f3061fc68863@google.com> Subject: [syzbot] [cgroups?] possible deadlock in task_rq_lock From: syzbot To: cgroups@vger.kernel.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, lizefan.x@bytedance.com, mkoutny@suse.com, syzkaller-bugs@googlegroups.com, tj@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: edd1ec2e3a9f Add linux-next specific files for 20240815 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=10ba4ed5980000 kernel config: https://syzkaller.appspot.com/x/.config?x=61ba6f3b22ee5467 dashboard link: https://syzkaller.appspot.com/bug?extid=ca14b36a46a8c541b509 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d063ca2a0d8c/disk-edd1ec2e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/08634f60bc99/vmlinux-edd1ec2e.xz kernel image: https://storage.googleapis.com/syzbot-assets/e6f08ac13836/bzImage-edd1ec2e.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ca14b36a46a8c541b509@syzkaller.appspotmail.com ------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 6.11.0-rc3-next-20240815-syzkaller #0 Not tainted ------------------------------------------------------ dhcpcd-run-hook/12621 is trying to acquire lock: ffffffff8e815038 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x20/0xa0 kernel/locking/semaphore.c:139 but task is already holding lock: ffff8880b913ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:587 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5762 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:587 raw_spin_rq_lock kernel/sched/sched.h:1485 [inline] task_rq_lock+0xc6/0x360 kernel/sched/core.c:689 cgroup_move_task+0x92/0x2d0 kernel/sched/psi.c:1161 css_set_move_task+0x72e/0x950 kernel/cgroup/cgroup.c:898 cgroup_post_fork+0x256/0x880 kernel/cgroup/cgroup.c:6690 copy_process+0x3ab1/0x3e30 kernel/fork.c:2620 kernel_clone+0x226/0x8f0 kernel/fork.c:2806 user_mode_thread+0x132/0x1a0 kernel/fork.c:2884 rest_init+0x23/0x300 init/main.c:712 start_kernel+0x47a/0x500 init/main.c:1103 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 -> #1 (&p->pi_lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5762 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4113 up+0x72/0x90 kernel/locking/semaphore.c:191 __up_console_sem kernel/printk/printk.c:340 [inline] __console_unlock kernel/printk/printk.c:2801 [inline] console_unlock+0x22f/0x4d0 kernel/printk/printk.c:3120 vprintk_emit+0x5dc/0x7c0 kernel/printk/printk.c:2348 _printk+0xd5/0x120 kernel/printk/printk.c:2373 set_capacity_and_notify+0x1ae/0x240 block/genhd.c:86 loop_set_size+0x44/0xb0 drivers/block/loop.c:232 loop_configure+0x9fb/0xec0 drivers/block/loop.c:1102 lo_ioctl+0x849/0x1f60 blkdev_ioctl+0x580/0x6b0 block/ioctl.c:676 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 ((console_sem).lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3136 [inline] check_prevs_add kernel/locking/lockdep.c:3255 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3871 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5145 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5762 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 down_trylock+0x20/0xa0 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x109/0x250 kernel/printk/printk.c:323 console_trylock kernel/printk/printk.c:2754 [inline] console_trylock_spinning kernel/printk/printk.c:1958 [inline] vprintk_emit+0x2aa/0x7c0 kernel/printk/printk.c:2347 _printk+0xd5/0x120 kernel/printk/printk.c:2373 __report_bug lib/bug.c:195 [inline] report_bug+0x346/0x500 lib/bug.c:219 handle_bug+0x60/0x90 arch/x86/kernel/traps.c:285 exc_invalid_op+0x1a/0x50 arch/x86/kernel/traps.c:309 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:621 lockdep_assert_rq_held kernel/sched/sched.h:1476 [inline] rq_clock kernel/sched/sched.h:1624 [inline] replenish_dl_new_period kernel/sched/deadline.c:777 [inline] update_curr_dl_se+0x66f/0x920 kernel/sched/deadline.c:1511 update_curr+0x575/0xb20 kernel/sched/fair.c:1176 put_prev_entity+0x3d/0x210 kernel/sched/fair.c:5505 put_prev_task_fair+0x4d/0x80 kernel/sched/fair.c:8686 put_prev_task kernel/sched/sched.h:2423 [inline] put_prev_task_balance+0x11d/0x190 kernel/sched/core.c:5886 __pick_next_task+0xc6/0x2f0 kernel/sched/core.c:5946 pick_next_task kernel/sched/core.c:6012 [inline] __schedule+0x725/0x4ad0 kernel/sched/core.c:6594 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6961 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5766 down_read_trylock+0x24f/0x3c0 kernel/locking/rwsem.c:1568 mmap_read_trylock include/linux/mmap_lock.h:163 [inline] get_mmap_lock_carefully mm/memory.c:6033 [inline] lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6093 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 __put_user_4+0x11/0x20 arch/x86/lib/putuser.S:86 schedule_tail+0x96/0xb0 kernel/sched/core.c:5205 ret_from_fork+0x24/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Chain exists of: (console_sem).lock --> &p->pi_lock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&p->pi_lock); lock(&rq->__lock); lock((console_sem).lock); *** DEADLOCK *** 2 locks held by dhcpcd-run-hook/12621: #0: ffff888011d14d98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff888011d14d98 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6033 [inline] #0: ffff888011d14d98 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6093 #1: ffff8880b913ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:587 stack backtrace: CPU: 1 UID: 0 PID: 12621 Comm: dhcpcd-run-hook Not tainted 6.11.0-rc3-next-20240815-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2189 check_prev_add kernel/locking/lockdep.c:3136 [inline] check_prevs_add kernel/locking/lockdep.c:3255 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3871 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5145 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5762 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 down_trylock+0x20/0xa0 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x109/0x250 kernel/printk/printk.c:323 console_trylock kernel/printk/printk.c:2754 [inline] console_trylock_spinning kernel/printk/printk.c:1958 [inline] vprintk_emit+0x2aa/0x7c0 kernel/printk/printk.c:2347 _printk+0xd5/0x120 kernel/printk/printk.c:2373 __report_bug lib/bug.c:195 [inline] report_bug+0x346/0x500 lib/bug.c:219 handle_bug+0x60/0x90 arch/x86/kernel/traps.c:285 exc_invalid_op+0x1a/0x50 arch/x86/kernel/traps.c:309 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:621 RIP: 0010:lockdep_assert_rq_held kernel/sched/sched.h:1476 [inline] RIP: 0010:rq_clock kernel/sched/sched.h:1624 [inline] RIP: 0010:replenish_dl_new_period kernel/sched/deadline.c:777 [inline] RIP: 0010:update_curr_dl_se+0x66f/0x920 kernel/sched/deadline.c:1511 Code: b5 50 fe ff ff 4c 89 ff ba 20 00 00 00 e8 e9 4f 00 00 e9 58 fe ff ff 4c 89 ef be 20 00 00 00 e8 b7 13 00 00 e9 46 fe ff ff 90 <0f> 0b 90 e9 be fb ff ff 89 f1 80 e1 07 38 c1 0f 8c b5 f9 ff ff 48 RSP: 0018:ffffc90004faf668 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff8880b903ea40 RCX: 0000000000000003 RDX: dffffc0000000000 RSI: ffffffff8c0adfc0 RDI: ffffffff8c609dc0 RBP: 0000000000000031 R08: ffff8880b902c883 R09: 1ffff11017205910 R10: dffffc0000000000 R11: ffffed1017205911 R12: ffff8880b903f468 R13: ffff8880b903f428 R14: 1ffff11017207e8f R15: ffff8880b903f858 update_curr+0x575/0xb20 kernel/sched/fair.c:1176 put_prev_entity+0x3d/0x210 kernel/sched/fair.c:5505 put_prev_task_fair+0x4d/0x80 kernel/sched/fair.c:8686 put_prev_task kernel/sched/sched.h:2423 [inline] put_prev_task_balance+0x11d/0x190 kernel/sched/core.c:5886 __pick_next_task+0xc6/0x2f0 kernel/sched/core.c:5946 pick_next_task kernel/sched/core.c:6012 [inline] __schedule+0x725/0x4ad0 kernel/sched/core.c:6594 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6961 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5766 Code: 2b 00 74 08 4c 89 f7 e8 2a 39 8c 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90004fafba0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920009f5f80 RCX: 5f14a1617595db00 RDX: dffffc0000000000 RSI: ffffffff8c0adfc0 RDI: ffffffff8c609dc0 RBP: ffffc90004fafce8 R08: ffffffff9375c837 R09: 1ffffffff26eb906 R10: dffffc0000000000 R11: fffffbfff26eb907 R12: 1ffff920009f5f7c R13: dffffc0000000000 R14: ffffc90004fafc00 R15: 0000000000000246 down_read_trylock+0x24f/0x3c0 kernel/locking/rwsem.c:1568 mmap_read_trylock include/linux/mmap_lock.h:163 [inline] get_mmap_lock_carefully mm/memory.c:6033 [inline] lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6093 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_4+0x11/0x20 arch/x86/lib/putuser.S:88 Code: 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 RSP: 0018:ffffc90004faff00 EFLAGS: 00050206 RAX: 000000000000314d RBX: 0000000000000000 RCX: 00007f0b3e35e650 RDX: 0000000000000000 RSI: ffffffff8c0adfc0 RDI: ffffffff8c609dc0 RBP: ffff8880217fa490 R08: ffffffff9018b8af R09: 1ffffffff2031715 R10: dffffc0000000000 R11: fffffbfff2031716 R12: 0000000000000000 R13: 0000000000000000 R14: 000000000000314d R15: dffffc0000000000 schedule_tail+0x96/0xb0 kernel/sched/core.c:5205 ret_from_fork+0x24/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 WARNING: CPU: 1 PID: 12621 at kernel/sched/sched.h:1476 lockdep_assert_rq_held kernel/sched/sched.h:1476 [inline] WARNING: CPU: 1 PID: 12621 at kernel/sched/sched.h:1476 rq_clock kernel/sched/sched.h:1624 [inline] WARNING: CPU: 1 PID: 12621 at kernel/sched/sched.h:1476 replenish_dl_new_period kernel/sched/deadline.c:777 [inline] WARNING: CPU: 1 PID: 12621 at kernel/sched/sched.h:1476 update_curr_dl_se+0x66f/0x920 kernel/sched/deadline.c:1511 Modules linked in: CPU: 1 UID: 0 PID: 12621 Comm: dhcpcd-run-hook Not tainted 6.11.0-rc3-next-20240815-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:lockdep_assert_rq_held kernel/sched/sched.h:1476 [inline] RIP: 0010:rq_clock kernel/sched/sched.h:1624 [inline] RIP: 0010:replenish_dl_new_period kernel/sched/deadline.c:777 [inline] RIP: 0010:update_curr_dl_se+0x66f/0x920 kernel/sched/deadline.c:1511 Code: b5 50 fe ff ff 4c 89 ff ba 20 00 00 00 e8 e9 4f 00 00 e9 58 fe ff ff 4c 89 ef be 20 00 00 00 e8 b7 13 00 00 e9 46 fe ff ff 90 <0f> 0b 90 e9 be fb ff ff 89 f1 80 e1 07 38 c1 0f 8c b5 f9 ff ff 48 RSP: 0018:ffffc90004faf668 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff8880b903ea40 RCX: 0000000000000003 RDX: dffffc0000000000 RSI: ffffffff8c0adfc0 RDI: ffffffff8c609dc0 RBP: 0000000000000031 R08: ffff8880b902c883 R09: 1ffff11017205910 R10: dffffc0000000000 R11: ffffed1017205911 R12: ffff8880b903f468 R13: ffff8880b903f428 R14: 1ffff11017207e8f R15: ffff8880b903f858 FS: 00007f0b3e35e380(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0b3e35e650 CR3: 000000006f33e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: update_curr+0x575/0xb20 kernel/sched/fair.c:1176 put_prev_entity+0x3d/0x210 kernel/sched/fair.c:5505 put_prev_task_fair+0x4d/0x80 kernel/sched/fair.c:8686 put_prev_task kernel/sched/sched.h:2423 [inline] put_prev_task_balance+0x11d/0x190 kernel/sched/core.c:5886 __pick_next_task+0xc6/0x2f0 kernel/sched/core.c:5946 pick_next_task kernel/sched/core.c:6012 [inline] __schedule+0x725/0x4ad0 kernel/sched/core.c:6594 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6961 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5766 Code: 2b 00 74 08 4c 89 f7 e8 2a 39 8c 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90004fafba0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920009f5f80 RCX: 5f14a1617595db00 RDX: dffffc0000000000 RSI: ffffffff8c0adfc0 RDI: ffffffff8c609dc0 RBP: ffffc90004fafce8 R08: ffffffff9375c837 R09: 1ffffffff26eb906 R10: dffffc0000000000 R11: fffffbfff26eb907 R12: 1ffff920009f5f7c R13: dffffc0000000000 R14: ffffc90004fafc00 R15: 0000000000000246 down_read_trylock+0x24f/0x3c0 kernel/locking/rwsem.c:1568 mmap_read_trylock include/linux/mmap_lock.h:163 [inline] get_mmap_lock_carefully mm/memory.c:6033 [inline] lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6093 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_4+0x11/0x20 arch/x86/lib/putuser.S:88 Code: 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 RSP: 0018:ffffc90004faff00 EFLAGS: 00050206 RAX: 000000000000314d RBX: 0000000000000000 RCX: 00007f0b3e35e650 RDX: 0000000000000000 RSI: ffffffff8c0adfc0 RDI: ffffffff8c609dc0 RBP: ffff8880217fa490 R08: ffffffff9018b8af R09: 1ffffffff2031715 R10: dffffc0000000000 R11: fffffbfff2031716 R12: 0000000000000000 R13: 0000000000000000 R14: 000000000000314d R15: dffffc0000000000 schedule_tail+0x96/0xb0 kernel/sched/core.c:5205 ret_from_fork+0x24/0x80 arch/x86/kernel/process.c:143 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 ---------------- Code disassembly (best guess): 0: 2b 00 sub (%rax),%eax 2: 74 08 je 0xc 4: 4c 89 f7 mov %r14,%rdi 7: e8 2a 39 8c 00 call 0x8c3936 c: f6 44 24 61 02 testb $0x2,0x61(%rsp) 11: 0f 85 85 01 00 00 jne 0x19c 17: 41 f7 c7 00 02 00 00 test $0x200,%r15d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp) 28: e0 45 * 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction 31: 00 00 33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1) 3a: 00 00 3c: 43 rex.XB 3d: c7 .byte 0xc7 3e: 44 rex.R 3f: 25 .byte 0x25 --- This report is generated by a bot. 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