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 6BA58147C74 for ; Fri, 19 Jul 2024 20:01:23 +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=1721419284; cv=none; b=D4J0V5/rvmBf921wwFKk/q5fPeEaA2awZDtEKl4mPiixwF1mUDUexDgMGw4mwQyM5TdteOmh4VXZSkLDOfTjMVb4DTJZQfChrWh0rAmQ1Kd9kQd1FUerWIAWIGua7xsuFcJSOYBG6OrCoG7vqRcbTnk7y2T2XHNt3tKZwS33tZ4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721419284; c=relaxed/simple; bh=/ODQVaF+kj4R5ZdkoO7A1k0FsHYPHHK+Iq8kAVC4/ms=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=E/CzVw7EPY6ilBRVYnXKA9PvU9tYv/C83xI4s5/+VafUMmKkZiq1l0rqu9SpWT3plN+Wp1zOLT4ZDCkIk1PKAUYqKLrFj3Lp3Q4ijo/Q5rQxUCgb7Mtq+cn65CoGbTORb2tM6NqimI6kw/szNwShewi9oPlq3B9nekqjQmkcv/4= 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-39884085529so8343715ab.2 for ; Fri, 19 Jul 2024 13:01:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721419282; x=1722024082; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=dovYDmlxyJjeuhItE/fiPUxUOKLE0VMXsjbN63JDOhA=; b=wSDMKiF1dM5RqgmFMcVxcFWbz3fHDAXmsCDfyX0qMdsR7To/nf6Rlqkf+jyrXcBgoy qsNuA46gSYRBTsfTR+uhi7yb9yGFKCpNwzWKKCtkesWAvwMjVIoMYAeTmwmZIicRfARO 6Os4A0cu50B9PifY6NNVhHToX4GUoLXhOymJmWx8JtYrusTxU8AJXrkoZMAGY1YBTt+l HRUAIVSvt9cSlat25bfX5eIhbIPpmE9jE7ElvxLKh2H1Wq9kRkz/D4IRNgIaHDT5t5Lb aJtp1dKmdVUIfI0cvaROk/HOmjE3Qeu6h1MFX3+NxvV14DPrNcmw3XBg/QtpG9R88eid Y+3A== X-Forwarded-Encrypted: i=1; AJvYcCVIoxCWZVNrx/t14WC6eDzWqlma5IKytPSpxG5XQonV+fI0W5JirV9S87krueHmG2FbcdITGZ82BzECSgxYPPPTva6ILovFJ4RnZmCQ X-Gm-Message-State: AOJu0YxdH4LB9ThyIzg5c5+cqBwmm6f/hKmBOEtCJAubvN0jPdMNoJcv vH9iVGuiysUOjRhG020iMvMzBTqdypf4VXXSm15WXOKlMRChGztWvZ1jVy4dzQDMbs41VNbgLvp 8w8LH8d0P24L09RLJVY8CYlD3qyeuiPy+nH2We/HkP9S0wikbNyF2s4A= X-Google-Smtp-Source: AGHT+IFxuYL0cY77FqP8wEtKHRdbGqJTbyhbKA1qpJXS29yHwDVtTM9hIsEM9XtFc9oCE2jRbQ24U+vQjV7NtQpUZ0n4TH5wae5b Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1c28:b0:395:fa9a:318e with SMTP id e9e14a558f8ab-398e17ab520mr686005ab.0.1721419282525; Fri, 19 Jul 2024 13:01:22 -0700 (PDT) Date: Fri, 19 Jul 2024 13:01:22 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000d8474e061d9f28be@google.com> Subject: [syzbot] [mm?] possible deadlock in mmap_read_lock From: syzbot To: Liam.Howlett@oracle.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, syzkaller-bugs@googlegroups.com, vbabka@suse.cz Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 3fe121b62282 Add linux-next specific files for 20240712 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1769e695980000 kernel config: https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce dashboard link: https://syzkaller.appspot.com/bug?extid=c0f0941337ade4c26ed1 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/8c6fbf69718d/disk-3fe121b6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/39fc7e43dfc1/vmlinux-3fe121b6.xz kernel image: https://storage.googleapis.com/syzbot-assets/0a78e70e4b4e/bzImage-3fe121b6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c0f0941337ade4c26ed1@syzkaller.appspotmail.com ============================================ WARNING: possible recursive locking detected 6.10.0-rc7-next-20240712-syzkaller #0 Not tainted -------------------------------------------- mount/4518 is trying to acquire lock: ffff88801d2b1498 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock+0x1c/0x60 include/linux/mmap_lock.h:144 but task is already holding lock: ffff88801d2b1498 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:144 [inline] ffff88801d2b1498 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x159/0xc80 mm/mmap.c:3396 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&mm->mmap_lock); lock(&mm->mmap_lock); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by mount/4518: #0: ffff88801d2b1498 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:144 [inline] #0: ffff88801d2b1498 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x159/0xc80 mm/mmap.c:3396 stack backtrace: CPU: 1 UID: 0 PID: 4518 Comm: mount Not tainted 6.10.0-rc7-next-20240712-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3034 check_deadlock kernel/locking/lockdep.c:3086 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3888 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526 mmap_read_lock+0x1c/0x60 include/linux/mmap_lock.h:144 unmap_single_vma+0x2a0/0x330 mm/memory.c:1832 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1904 exit_mmap+0x264/0xc80 mm/mmap.c:3412 __mmput+0x115/0x390 kernel/fork.c:1347 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x27f0 kernel/exit.c:869 do_group_exit+0x207/0x2c0 kernel/exit.c:1031 __do_sys_exit_group kernel/exit.c:1042 [inline] __se_sys_exit_group kernel/exit.c:1040 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040 x64_sys_call+0x26c3/0x26d0 arch/x86/include/generated/asm/syscalls_64.h:232 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 RIP: 0033:0x7fd19a876a90 Code: Unable to access opcode bytes at 0x7fd19a876a66. RSP: 002b:00007ffd90b476e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fd19a967860 RCX: 00007fd19a876a90 RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00007fd19a967860 R08: 00007ffd90b47560 R09: 00007ffd90b47640 R10: 00007ffd90b475a0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd19a96b658 R15: 0000000000000001 mount (4518) used greatest stack depth: 23680 bytes left --- 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@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. 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