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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92062C433EF for ; Fri, 29 Apr 2022 06:42:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354679AbiD2Gpk (ORCPT ); Fri, 29 Apr 2022 02:45:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230104AbiD2Gph (ORCPT ); Fri, 29 Apr 2022 02:45:37 -0400 Received: from mail-io1-f71.google.com (mail-io1-f71.google.com [209.85.166.71]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4A24BB097 for ; Thu, 28 Apr 2022 23:42:18 -0700 (PDT) Received: by mail-io1-f71.google.com with SMTP id x16-20020a6bfe10000000b006409f03e39eso6049561ioh.7 for ; Thu, 28 Apr 2022 23:42:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=l3uvIzx8owff86p9JQl2Fu7AJprV7tqHPmZVvDWo23Y=; b=QGXwWWaAAMtOR28Fl/btibjvXGNuCQnUF9WEEJ4Ea9H8apRHpzqvxiJC/xos02hqXY 2LTlp1aJ9R5cLSZixULkZrQGLsfLkKCH3uBIiTz/x1eicAVx2IpQlKIZDg1TtvbzbSNo jLCD2iFcJUUYFNUPzkWgjGdCMA7psSVMUbGLqD8XyZ+qqux4XLieqvK21HSchO1S2XqY boR0HS7ygyDAC1P5KJ19m8X9nUz2YJ/8O7n6ixjEn1yDy4AaNX9qxsQfKsj80ykx9f3e +d3OQoSUWgDFM4whbHa5TUJ/FV0WvDst5/BuMTchQ2s45zFeGAvhjA/CQDBS3OXIpUHd 5iLw== X-Gm-Message-State: AOAM533gctiKIsEGTmvp1dt+yqBRfy98c1WPrf55cvns/ZIWl3bB+7sm PAQBsHxEzRZL87/mniYFSeuRkZ5KGOob09qwx16PQbuaHldY X-Google-Smtp-Source: ABdhPJx4eNeHQmphQOEWZdtB8HqQTm1RUTsECKQxO5MwZe1wK0DtEboWIgLl45zB6dkp4eQiCGbw1L54lhqfnhXYHV/3KQR/ULPe MIME-Version: 1.0 X-Received: by 2002:a05:6638:cd3:b0:32a:eec5:bbca with SMTP id e19-20020a0566380cd300b0032aeec5bbcamr10551459jak.99.1651214538309; Thu, 28 Apr 2022 23:42:18 -0700 (PDT) Date: Thu, 28 Apr 2022 23:42:18 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000001044205ddc55870@google.com> Subject: [syzbot] possible deadlock in do_page_fault From: syzbot To: ebiederm@xmission.com, keescook@chromium.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk 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: 0966d385830d riscv: Fix auipc+jalr relocation range checks git tree: git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes console output: https://syzkaller.appspot.com/x/log.txt?x=1128ae72f00000 kernel config: https://syzkaller.appspot.com/x/.config?x=6295d67591064921 dashboard link: https://syzkaller.appspot.com/bug?extid=f8181becdab66ab4b181 compiler: riscv64-linux-gnu-gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: riscv64 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+f8181becdab66ab4b181@syzkaller.appspotmail.com ============================================ WARNING: possible recursive locking detected 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Not tainted -------------------------------------------- dhcpcd-run-hook/3780 is trying to acquire lock: ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: do_page_fault+0x24e/0xa3c arch/riscv/mm/fault.c:285 but task is already holding lock: ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: setup_arg_pages+0x1aa/0x4b8 fs/exec.c:793 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 dhcpcd-run-hook/3780: #0: ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #0: ffffaf8010608d18 (&mm->mmap_lock){++++}-{3:3}, at: setup_arg_pages+0x1aa/0x4b8 fs/exec.c:793 stack backtrace: CPU: 1 PID: 3780 Comm: dhcpcd-run-hook Not tainted 5.17.0-rc1-syzkaller-00002-g0966d385830d #0 Hardware name: riscv-virtio,qemu (DT) Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:113 [] show_stack+0x34/0x40 arch/riscv/kernel/stacktrace.c:119 [] __dump_stack lib/dump_stack.c:88 [inline] [] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:106 [] dump_stack+0x1c/0x24 lib/dump_stack.c:113 [] print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] [] check_deadlock kernel/locking/lockdep.c:2999 [inline] [] validate_chain kernel/locking/lockdep.c:3788 [inline] [] __lock_acquire+0x1dcc/0x333e kernel/locking/lockdep.c:5027 [] lock_acquire.part.0+0x1d0/0x424 kernel/locking/lockdep.c:5639 [] lock_acquire+0x54/0x6a kernel/locking/lockdep.c:5612 [] down_read+0x3c/0x54 kernel/locking/rwsem.c:1461 [] mmap_read_lock include/linux/mmap_lock.h:117 [inline] [] do_page_fault+0x24e/0xa3c arch/riscv/mm/fault.c:285 [] ret_from_exception+0x0/0x10 [] __stack_depot_save+0x40/0x4b2 lib/stackdepot.c:360 --- 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.