From nobody Wed Sep 11 15:02:11 2024 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4X3kLt32Ydz5Tfx6; Wed, 11 Sep 2024 15:02:14 +0000 (UTC) (envelope-from kp@FreeBSD.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "R10" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4X3kLt2Yhlz41pD; Wed, 11 Sep 2024 15:02:14 +0000 (UTC) (envelope-from kp@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1726066934; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CzAhauBw5pdfG0GQpOH8QZJORoWSa6P6b8651b0ZCqA=; b=hFdh525vNw0I5UOZ825Vi3TUsVS5VtkBIjWk6qvJLEJ7Tzyjqu4cqA8EZOa7bGCxj8WY1n jiLjugV+TLXVbm9uSQfoHbk3I+zcAQkjHFhrjZTlvhS46pDRnYa2rY0QnLlSyo5aqJmaJW 5XBwvKbuKgjfYVJ6IO+JHq+bGRK5iDck7fomXvXz+a3Aq5g3s6nupDD3y3aTROcVGgvhTn nkLy0G5nl+2DsNUtCvHjHivfahs26O9GmEIaHWDw12bgs9kqgFqYUv3ePVuPnc5ff2/02H vXZDSVxsji/JgvzApnu2gkA6B83W7qSCSusKwBfEfYhXRDkREhgYAbK5Rva2yw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1726066934; a=rsa-sha256; cv=none; b=qhgyYuKTt/vjHXbl7dc7aIZ5MxZyXZhAru64T7deZAvZ0GaGcMO7EpCe9h2sLf6f/K/Abx i/4v287SNG2cY4u2o9g6YQk3j0IFsHCR4beU4Zl8BoEgwDAQku02KngOleL5XBTDK0eWuW MynsRCmHHRXp4cmpUULCYw4JT5rSw9c7fnOXr4Awm3NP7YYm94/RUa+ULHhZ/bhax0s2v+ HhjAyvacaGgEfcbxMutH0QCP3JVh3kkqajtygMgmZoTx22GDqnlliQw6yygSQLzFpM5JsJ TRRdYtAHqENzBZBVmVVnkY/cqz8A1/INNUUdoLbzoDwGEMzkeE4Y4Om2zldy8w== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1726066934; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CzAhauBw5pdfG0GQpOH8QZJORoWSa6P6b8651b0ZCqA=; b=LEwojLwd5REupT4IVSq5e8QsAMmXrKKciqL9VAtH7a8MbyPIP4eAO2lqBI+eW93KiRw5sz FECpw9JUvyQIBlIpDThTTght5z+KIZymYHwhL+WjaeEd8Nqiw0Q1Hfc0LFXEsf3/uP2ch2 sfQUplnVDVeu+T1hOvB524kp2pH/w3oTqMhPAWlst+DfG5OaSsvMvw1DdDIIJJP2hQgKCO Fxl8dMGBXTcu6+Yf/B+NveIDYeX8cB18uLyH8Hrl0Fa7HdQih/rqu2WVYHq8Ox3vnkuGW0 tzsKKrFY+/SDqWXkx9O4w5gtloGh4MJ9nw4g2pQGt+RGOV2wR0hX75frBmR9cg== Received: from venus.codepro.be (venus.codepro.be [5.9.86.228]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "mx1.codepro.be", Issuer "R11" (verified OK)) (Authenticated sender: kp) by smtp.freebsd.org (Postfix) with ESMTPSA id 4X3kLt1YRkz1Cx9; Wed, 11 Sep 2024 15:02:14 +0000 (UTC) (envelope-from kp@FreeBSD.org) Received: by venus.codepro.be (Postfix, authenticated sender kp) id 6C83A4FA93; Wed, 11 Sep 2024 17:02:12 +0200 (CEST) From: Kristof Provost To: Mark Johnston Cc: src-committers@freebsd.org, dev-commits-src-all@freebsd.org, dev-commits-src-main@freebsd.org Subject: Re: git: f08247fd888e - main - Assert that mbufs are writable if we write to them Date: Wed, 11 Sep 2024 17:02:11 +0200 X-Mailer: MailMate (1.14r5937) Message-ID: In-Reply-To: References: <202409111118.48BBIQ2h065089@gitrepo.freebsd.org> List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 11 Sep 2024, at 16:45, Mark Johnston wrote: > On Wed, Sep 11, 2024 at 11:18:26AM +0000, Kristof Provost wrote: >> The branch main has been updated by kp: >> >> URL: https://cgit.FreeBSD.org/src/commit/?id=3Df08247fd888e6f7db0ecf2a= aa39377144ac40b4c >> >> commit f08247fd888e6f7db0ecf2aaa39377144ac40b4c >> Author: Kristof Provost >> AuthorDate: 2024-09-10 20:15:31 +0000 >> Commit: Kristof Provost >> CommitDate: 2024-09-11 11:17:48 +0000 >> >> Assert that mbufs are writable if we write to them >> >> m_copyback() modifies the mbuf, so it must be a writable mbuf. > > This change still triggers a panic for me when running KTLS tests. I > note that EXTPG mbufs always have M_RDONLY set, but I'm not quite sure > why. I suspect such mbufs need special handling with respect to the ne= w > assertion. > > syzbot also triggered this panic: > https://syzkaller.appspot.com/bug?extid=3D58c918369f9dc323409d > Yeah, I saw that one before I went out for a bike ride. Clearly something is wrong. Either ktls is using read-only buffers or the= M_WRITABLE() macro isn=E2=80=99t quite smart enough to spot this specifi= c case. I=E2=80=99m not familiar enough with ktls to easily tell which. I=E2=80=99ll back this assertion change out for now, so we=E2=80=99re not= panicing test machines while we figure this out. Best regards, Kristof