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[23.128.96.18]) by mx.google.com with ESMTP id h12si4525130edq.232.2020.10.08.14.37.35; Thu, 08 Oct 2020 14:37:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=appspotmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730354AbgJHU2L (ORCPT + 99 others); Thu, 8 Oct 2020 16:28:11 -0400 Received: from mail-io1-f78.google.com ([209.85.166.78]:39005 "EHLO mail-io1-f78.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730312AbgJHU2L (ORCPT ); Thu, 8 Oct 2020 16:28:11 -0400 Received: by mail-io1-f78.google.com with SMTP id s135so4632098ios.6 for ; Thu, 08 Oct 2020 13:28:11 -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:in-reply-to:message-id:subject :from:to; bh=7y3B3XsOiPTLYLIDns6NguVsL9ucnpw4TXcZn72tI0c=; b=UygwF6DWIk2VhJRxUu6cJwV/zXPTJLav7yLMs9vuCTlniBMHVbK40VDZ34ITa9cGmz oNrTSLHxvoNLtZGsokAm6PrzxiGGqnbF6RnI/HLQRhkit1OHRsdtnntKI7wRgdAKDQHS GdSTkGZGKmQUODkkZSdXlwyNU9A4BIndMT20J4csFFy+hUUtkS3tB9Yl2Ibuyn4m8WXC H3UPucyhGPYRD6o8cSCZsPu+mhFjukSbuxmHUVQNzhilQoELycUJw9tXrOcwQV0f693G pOw0Cp48N4xDja4FwQY2jrqKxl/Zy1hnbw9DXZTnoLXbuQDLbGPiIImmD4mQSeHsrrd+ khCg== X-Gm-Message-State: AOAM533egAGwMKazIZUA/sQMymESh/q1Y4q5/VxsnStTQ6b2CRowCtM0 2rLtfDkhHClS3cWWi8urIH/LQ2J2BDyMyxgHrPCDFv5TmMSX MIME-Version: 1.0 X-Received: by 2002:a92:1f44:: with SMTP id i65mr7622723ile.280.1602188890683; Thu, 08 Oct 2020 13:28:10 -0700 (PDT) Date: Thu, 08 Oct 2020 13:28:10 -0700 In-Reply-To: <00000000000084dcbd05b12a3736@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000b1412b05b12eab0a@google.com> Subject: Re: general protection fault in percpu_ref_exit From: syzbot To: axboe@kernel.dk, bcrl@kvack.org, hch@lst.de, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, ming.lei@redhat.com, syzkaller-bugs@googlegroups.com, tj@kernel.org, viro@zeniv.linux.org.uk, vkabatov@redhat.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot has bisected this issue to: commit 2b0d3d3e4fcfb19d10f9a82910b8f0f05c56ee3e Author: Ming Lei Date: Thu Oct 1 15:48:41 2020 +0000 percpu_ref: reduce memory footprint of percpu_ref in fast path bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=126930d0500000 start commit: 8b787da7 Add linux-next specific files for 20201007 git tree: linux-next final oops: https://syzkaller.appspot.com/x/report.txt?x=116930d0500000 console output: https://syzkaller.appspot.com/x/log.txt?x=166930d0500000 kernel config: https://syzkaller.appspot.com/x/.config?x=aac055e9c8fbd2b8 dashboard link: https://syzkaller.appspot.com/bug?extid=fd15ff734dace9e16437 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=119a0568500000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=106c0a8b900000 Reported-by: syzbot+fd15ff734dace9e16437@syzkaller.appspotmail.com Fixes: 2b0d3d3e4fcf ("percpu_ref: reduce memory footprint of percpu_ref in fast path") For information about bisection process see: https://goo.gl/tpsmEJ#bisection