From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f80.google.com (mail-oo1-f80.google.com [209.85.161.80]) (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 CEBAB2BD5B4 for ; Sat, 2 May 2026 11:25:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777721135; cv=none; b=gQhpJHnR//cxGyHhP1ZbkTvRRiim/iGQjiFJsXI1Qm3tkNbls7YBGNFFkaFm8aXoc89WnjMvvRyboUEXqtWckL9INfUH5EyAyYDmroTBMderCdWtLxRQat2/ctfyNhRLxj3hDWRi7K1APsnjx3WTiegc7Agnhajb24L1gDZngvo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777721135; c=relaxed/simple; bh=+9Yc7qg/I+f9u7z+qWPoZ1R53fPmSyHI7BvByHY2dTU=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=J6T2fruGSoXieMC29Ban/vl5ZUU814btjzTZ/0Xh0ZN+3lm6gEr7++aM9zEf7+LPIOVNGZAbfh8hHEavUoD2LlbKSgkAN8bw7K7HjytlyK4TeOZwRt5UV1QLa4wJPblChRLRrfwcj92ecx84j9JLZxAnWqrE1OlJUDZtF2HfW44= 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=209.85.161.80 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-oo1-f80.google.com with SMTP id 006d021491bc7-69491bd267fso6461419eaf.0 for ; Sat, 02 May 2026 04:25:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777721133; x=1778325933; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=HtmaSIHLoot0vOXzcU/27GViHD+QoZG2kMWciMiygUE=; b=muVlNVh6jlM6t1Xg16EsryRPHUkdLyE1iuWaiP16P7eL6vhPTgUAYLFtmQLxjdX8OT 3QGLv5YR4/CGL2zxogr4WfUcqj80pQEz0jherZZq/ABL4QOseMHAGX+YvP1s2MdcKDhX LX0FJjwuoeblEe6K2OBSYLu6kWfnKBEBTgmao5Z7yM5HZd0UbccIc+D7hkQ5SydsVSzD glg6863R7w+HsozpCRqfRzF8pQuvb+R6wq5yTcxbdPYzkx8EohajPIZK49OW4/qoDaNy usVc8NXtDxT0L+maa2NyszeC86idpe9q1EZykYqIgRkIrQB2t/723DArV+V6xNrbIJs7 LQxA== X-Forwarded-Encrypted: i=1; AFNElJ89i/uLCfR/5H4cgxyueaDXABqj8Nfw8GbdCFcF8GZOHV4Gd4U7evhf9CJ6hzLf1xY2MoZzTmssdY7rJl0=@vger.kernel.org X-Gm-Message-State: AOJu0YwQAimfi7qpI+QO+jd+1daKcfyr2JG5NFYIzAPaVGD+kNon5fBt 8WjvhyGtB7Lsx8jPTpU6q45pisy3GhqGtAOvfsZvf4fpYumD9Yt51TALi1ZrJ1bRQwdlWjolsvB hTJxGwRpuWsi9kb2X4qXDZQ8TFL7NuTql/Ro4LeatgN4q0bKpjCySOaubox0= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:3109:b0:696:6440:9e33 with SMTP id 006d021491bc7-69697d89d8cmr1270626eaf.43.1777721132959; Sat, 02 May 2026 04:25:32 -0700 (PDT) Date: Sat, 02 May 2026 04:25:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69f5df2c.050a0220.3cbe47.0017.GAE@google.com> Subject: [syzbot] [mm?] WARNING: bad unlock balance in do_fault From: syzbot To: Liam.Howlett@oracle.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ljs@kernel.org, shakeel.butt@linux.dev, surenb@google.com, syzkaller-bugs@googlegroups.com, vbabka@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 3b3bea6d4b9c Merge tag 'cgroup-for-7.1-rc1-fixes' of git:/.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11dbb326580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d0f0911eedbc130a dashboard link: https://syzkaller.appspot.com/bug?extid=c4f59f1ba89c777b77d4 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-3b3bea6d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/90f65aee39f9/vmlinux-3b3bea6d.xz kernel image: https://storage.googleapis.com/syzbot-assets/9c44f0af2bac/bzImage-3b3bea6d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c4f59f1ba89c777b77d4@syzkaller.appspotmail.com ===================================== WARNING: bad unlock balance detected! syzkaller #0 Not tainted ------------------------------------- dhcpcd-run-hook/5691 is trying to release lock (rcu_read_lock) at: [] rcu_lock_release include/linux/rcupdate.h:310 [inline] [] rcu_read_unlock include/linux/rcupdate.h:869 [inline] [] do_fault_around mm/memory.c:5854 [inline] [] do_read_fault mm/memory.c:5884 [inline] [] do_fault+0x9b4/0x1750 mm/memory.c:6027 but there are no more locks to release! other info that might help us debug this: 1 lock held by dhcpcd-run-hook/5691: #0: ffff888024e92a88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310 stack backtrace: CPU: 3 UID: 0 PID: 5691 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_unlock_imbalance_bug.part.0+0xfb/0x106 kernel/locking/lockdep.c:5298 print_unlock_imbalance_bug kernel/locking/lockdep.c:5278 [inline] __lock_release kernel/locking/lockdep.c:5537 [inline] lock_release kernel/locking/lockdep.c:5889 [inline] lock_release+0x28d/0x310 kernel/locking/lockdep.c:5875 rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:869 [inline] do_fault_around mm/memory.c:5854 [inline] do_read_fault mm/memory.c:5884 [inline] do_fault+0x9b9/0x1750 mm/memory.c:6027 do_pte_missing mm/memory.c:4550 [inline] handle_pte_fault mm/memory.c:6411 [inline] __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7ff2e82ebfeb Code: 08 48 8b 78 08 48 89 13 e8 5e f9 ff ff 97 e8 bb ff ff ff 48 09 e8 40 0f 95 c5 40 0f b6 ed eb 04 48 83 2b 08 48 95 5a 5b 5d c3 <55> 53 89 fb 48 83 ec 18 48 8b 3e 48 89 74 24 08 e8 a9 e7 f9 ff 80 RSP: 002b:00007fff321b8cc8 EFLAGS: 00010287 RAX: 00007ff2e8336190 RBX: 0000564f23c56910 RCX: 0000000000000002 RDX: 0000564f23c56910 RSI: 0000564f23c5f120 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000020 R10: 0000000000000040 R11: 0000000000000000 R12: 0000564f23c5ee50 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 ------------[ cut here ]------------ rrln < 0 || rrln > RCU_NEST_PMAX WARNING: kernel/rcu/tree_plugin.h:443 at __rcu_read_unlock kernel/rcu/tree_plugin.h:443 [inline], CPU#3: dhcpcd-run-hook/5691 WARNING: kernel/rcu/tree_plugin.h:443 at __rcu_read_unlock+0x235/0x5e0 kernel/rcu/tree_plugin.h:430, CPU#3: dhcpcd-run-hook/5691 Modules linked in: CPU: 3 UID: 0 PID: 5691 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__rcu_read_unlock kernel/rcu/tree_plugin.h:443 [inline] RIP: 0010:__rcu_read_unlock+0x235/0x5e0 kernel/rcu/tree_plugin.h:430 Code: 74 11 c7 45 58 01 00 00 00 bf 09 00 00 00 e8 92 a3 da ff e8 fd de 22 00 9c 58 f6 c4 02 0f 85 dd 02 00 00 fb e9 57 fe ff ff 90 <0f> 0b 90 5b 5d 41 5c 41 5d 41 5e 41 5f e9 d9 f0 9c 09 e8 84 60 87 RSP: 0000:ffffc90003f9fbe8 EFLAGS: 00010286 RAX: 00000000ffffffff RBX: ffff88802a16a500 RCX: ffffffff81e7203e RDX: 0000000000000000 RSI: ffffffff8def466d RDI: ffff88802a16a9c4 RBP: 0000000000000100 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000080000000 R11: 0000000000000012 R12: 0000000000000001 R13: 00000000000000e0 R14: ffffc90003f9fd68 R15: 00000000000000f0 FS: 00007ff2e7fcfc80(0000) GS:ffff888097480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff2e82ebfeb CR3: 0000000050d47000 CR4: 0000000000352ef0 Call Trace: rcu_read_unlock include/linux/rcupdate.h:871 [inline] do_fault_around mm/memory.c:5854 [inline] do_read_fault mm/memory.c:5884 [inline] do_fault+0x9be/0x1750 mm/memory.c:6027 do_pte_missing mm/memory.c:4550 [inline] handle_pte_fault mm/memory.c:6411 [inline] __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7ff2e82ebfeb Code: 08 48 8b 78 08 48 89 13 e8 5e f9 ff ff 97 e8 bb ff ff ff 48 09 e8 40 0f 95 c5 40 0f b6 ed eb 04 48 83 2b 08 48 95 5a 5b 5d c3 <55> 53 89 fb 48 83 ec 18 48 8b 3e 48 89 74 24 08 e8 a9 e7 f9 ff 80 RSP: 002b:00007fff321b8cc8 EFLAGS: 00010287 RAX: 00007ff2e8336190 RBX: 0000564f23c56910 RCX: 0000000000000002 RDX: 0000564f23c56910 RSI: 0000564f23c5f120 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000020 R10: 0000000000000040 R11: 0000000000000000 R12: 0000564f23c5ee50 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup