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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 90329C77B7C for ; Wed, 10 May 2023 07:47:54 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pweY2-0001N1-T9; Wed, 10 May 2023 03:47:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pweY1-0001Mo-Sp; Wed, 10 May 2023 03:47:41 -0400 Received: from mo4-p01-ob.smtp.rzone.de ([85.215.255.53]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pweXz-0000bx-SR; Wed, 10 May 2023 03:47:41 -0400 ARC-Seal: i=1; a=rsa-sha256; t=1683704854; cv=none; d=strato.com; s=strato-dkim-0002; b=c+CEDxctFw9MGyl+F0u5UkTweo5v0QOac6s+9XQ6Ohek4sU9Nb3NjkBNLbSQc3X29p 2CdyvI911gHLpvKz5hoLu9JjuuFsgzR03VUCr3SZIXms9NAuW4Vy/4dkmPrw/6Bmb3VE UaKnuTGT9JE19bACRywlR5HYy5J9SP5i+dEpyT0WfPDm+I1nkuMMxICFkySkA8PBh//v zYzqBsOlfTKBjA5deCHf/cJKV82V3nAqC+1UXGM60F9mI92Y7GYFpBzciNLxVDzBA3FR xyNUlQNb3+DhS06zMkpwAnhugHKGDm9+gjh8CWGnwJ9h94hc8eWIx8zj2CkabD+uw4zd DTUg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; t=1683704854; s=strato-dkim-0002; d=strato.com; h=References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Cc:Date: From:Subject:Sender; bh=fpMbxRbaAtliiEqD3yXPNT5MQEGuwjFCZILVH7eZVLE=; b=XkgGWnjmjh0LovQ0y1CUSjs5+WREcOsUOUk2zLuJUHTOca4+aEyZByxpsEApoFkNRP 3vb/lhdYvmeiRPtqOpm+hO1CnErrXS3BbUw3z7UXTxAPf6IM6u/fYlRmL/f1ncMbd5Vd vc4PvG8GsrAWhNm9AWYo+sKFlMdH0Hxq7+tfiMdv+1UbkfeuqJ8o9sBaFNC3dvXfYQ+N K2RHk8N/icC5Qdh+7z6PT7Qfi2nSU6NZlRagbdQzoEUpOpF1fUI/D3C/cK+CJ4y26ogE OikicXS+faaliiYj5wACVqMsdvoINRbdK0p9qbyFkdc7RigZiHZqSIuBUk/WE3Gi70iT ei1Q== ARC-Authentication-Results: i=1; strato.com; arc=none; dkim=none X-RZG-CLASS-ID: mo01 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1683704854; s=strato-dkim-0002; d=aepfle.de; h=References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Cc:Date: From:Subject:Sender; bh=fpMbxRbaAtliiEqD3yXPNT5MQEGuwjFCZILVH7eZVLE=; b=VtAUsFP4F+JSerLh8MZ7ULl38l9Hj85X55W1atDN/NNfPVXUtGM+qCJwizusxv+wTa k1OQywRxHqXhEF3+6Tp3C0rZfJ0hnxu3t5FZPVAgSMlFNIiQrS/l2caM/mw8BlrSQ+bc I1o3q2aH4XKDsO5iMgxenQnNE1DsBRu47zqWRl4wMrLEtwXfffrG1DHxQn4SEg/rAcDK 2xPb1GStX2e7yg6n1ZFTCf/sY+bfKs97VNWNNnBmaIX5Ji+bO9t9VZPxvKRa6rB2yuIN 4v4Fkyoq3W4RFutJiRg+JvonSO8WuY1KmqSLnkXwsfRM4BxaiI4/ehGUgDCBfKozldBN 2IiQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; t=1683704854; s=strato-dkim-0003; d=aepfle.de; h=References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Cc:Date: From:Subject:Sender; bh=fpMbxRbaAtliiEqD3yXPNT5MQEGuwjFCZILVH7eZVLE=; b=krAmvBX6oRNRFqJB0vvQOHessJgvwMw5kZBnFSJhW2UNLeDlEB/rHcpLzraKPVRrcM 4iIe2hNTHbCfynLvd7Dg== X-RZG-AUTH: ":P2EQZWCpfu+qG7CngxMFH1J+3q8wa/QLpd5ylWvMDX3y/OuD5rXVisR4ARWIYxzstZKeVom+bauo0LKSCjuo5iX5xLikmg==" Received: from sender by smtp.strato.de (RZmta 49.4.0 AUTH) with ESMTPSA id x6987cz4A7lY8oh (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Wed, 10 May 2023 09:47:34 +0200 (CEST) Date: Wed, 10 May 2023 09:47:19 +0200 From: Olaf Hering To: Paolo Bonzini , John Snow , Stefano Stabellini Cc: xen-devel@lists.xenproject.org, qemu-devel@nongnu.org, qemu-block@nongnu.org, Philippe =?UTF-8?B?TWF0aGlldS1EYXVkw6k=?= Subject: Re: [PATCH v2] piix: fix regression during unplug in Xen HVM domUs Message-ID: <20230510094719.26fb79e5.olaf@aepfle.de> In-Reply-To: <20230509225818.GA16290@aepfle.de> References: <20210317070046.17860-1-olaf@aepfle.de> <4441d32f-bd52-9408-cabc-146b59f0e4dc@redhat.com> <20210325121219.7b5daf76.olaf@aepfle.de> <20230509225818.GA16290@aepfle.de> X-Mailer: Claws Mail 20230504T161344.b05adb60 hat ein Softwareproblem, kann man nichts machen. MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/R/2sS42QIzwYzqn.D6NtiKf"; protocol="application/pgp-signature"; micalg=pgp-sha256 Content-Transfer-Encoding: 7bit Received-SPF: none client-ip=85.215.255.53; envelope-from=olaf@aepfle.de; helo=mo4-p01-ob.smtp.rzone.de X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_PASS=-0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org --Sig_/R/2sS42QIzwYzqn.D6NtiKf Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Wed, 10 May 2023 00:58:27 +0200 Olaf Hering : > In my debugging (with v8.0.0) it turned out the three pci_set_word > causes the domU to hang. In fact, it is just the last one: >=20 > pci_set_byte(pci_conf + 0x20, 0x01); /* BMIBA: 20-23h */ >=20 > It changes the value from 0xc121 to 0x1. If I disable just "pci_set_word(pci_conf + PCI_COMMAND, 0x0000);" it works = as well. It changes the value from 0x5 to 0. In general I feel it is wrong to fiddle with PCI from the host side. This is most likely not the intention of the Xen unplug protocol. I'm sure the guest does not expect such changes under the hood. It happens to work by luck with pvops kernels because their PCI discovery is done after the unplug. So, what do we do here to get this off the table? Olaf --Sig_/R/2sS42QIzwYzqn.D6NtiKf Content-Type: application/pgp-signature Content-Description: Digitale Signatur von OpenPGP -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEE97o7Um30LT3B+5b/86SN7mm1DoAFAmRbTAcACgkQ86SN7mm1 DoBRfg//cAC+i271H3HLPzevJR+ToZ3Ywxfz+e53Xk6RnVZfy79aWT9delbKNvoo /sEmxurXHIjU2vHju5bE7C4s8J8oTjjY/vgJrnBp0IIoDNF7s2DNPdpWP31bdC32 AzWMm2kzCWYbTf2k0ByGQ2FlyxJi17fbXaIgwMsmhG6WhCbf2CTD+ZPoW5DLPlI6 nhJaFpge2Lw5PjebKkZh/eHB9GmQ7o/Z1fs2VnghfJeeyeBAtx7UuBwol3ZX6rTS V76Ftd+PcXPvrw3UkUyj6VE38YJT95bIHpEf4oR9iiPlvE/Lv8wYq7fdCdbvkKQd yIyJzrg8S2YAFWxBVpQVNOYXhFTbhgyQr331OslGBGMRaZ/F9vQkuBzK+d6pVAHv bTJJhDYqY1kr+gJerGPW5+gWoaCegEIzMj7fjYNVWHCh51hG7eJw8cYkFEPWApIP XhKyulCg+vaCRO1/TTsrq2mXQ8GDUp+Xm1iorJ69CC9i2qQ8fWM8EJ8lVZZddas2 3tSwjtdrt/MWvmetZK0yM4jZint6nj0w4iTOs/MR8Kya/3bLbKRNDZczsIrNd8p6 5UrR33AMreG41Nkob/IRltibnHEDhHPgK9GJfC2yWj49Tf4H8PYTlT6HxOIeyX4r OXp83UJ40RKuyvu7GJIxNfOgFdLTeZZEQSxAkxW4lrTFxuTQgls= =+t5t -----END PGP SIGNATURE----- --Sig_/R/2sS42QIzwYzqn.D6NtiKf--