From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out4-smtp.messagingengine.com (out4-smtp.messagingengine.com [66.111.4.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9DAA81857; Tue, 18 Oct 2022 03:52:22 +0000 (UTC) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.nyi.internal (Postfix) with ESMTP id 8802F5C021E; Mon, 17 Oct 2022 23:52:21 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Mon, 17 Oct 2022 23:52:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= invisiblethingslab.com; h=cc:cc:content-type:date:date:from:from :in-reply-to:message-id:mime-version:reply-to:sender:subject :subject:to:to; s=fm3; t=1666065141; x=1666151541; bh=W4YdM85rRr G8oSndD/hIo0CDcv3F1jsFFOfc7EWctI4=; b=QHQht0C4dVlXl/FbBF9w7NG9o4 4UgJ8jOEvdug/MzJJ9yawQ2Q77WksxxyG4F6cmNvBRNWaZee4kxO8M8uVHjxTbmr r4VNCeI2ideFuwp5rJugzV1+T7PLZ9faCVHQSv7esIKDbY/2FENPFRcsiFm9gozT qcZM8xYq5hy8b0+8fFEgUuCtQ5FFS01tWWWGxJ4yqkYu6ER1+hFvX1YH03VoaoFI ie5svNFkqEUybqyUJu+cs6Kt/T6v1vyeII04OOEN7+vr06JBHH+NSjIFqmi7k6Pf Ldmeor+EMZ6EJoO4Vf0ZJx7YFC9KyOOdMVsHoCmED+x4Hqy/PLbi5/j0yAgA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:message-id:mime-version :reply-to:sender:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm3; t=1666065141; x= 1666151541; bh=W4YdM85rRrG8oSndD/hIo0CDcv3F1jsFFOfc7EWctI4=; b=I r2PL6lYzUUvpbh6Rkts4EO0ht4E+sf7lcSHJvbPy8vJCFhdS3itiRXhTAPuCbDkr 0FaBeLbEMqzg3ZYCzr80DkLJqXgsLwi8v6MICwzFkumS0abPydv/SiCZ+E8XlCzZ taiWPK2yZPpAjpRJLMdflzzLlhQL2rUdlDZhAxluRu1Aq0ypYa73sHJxeIU6U6Zp grwAH3BQF1bu1qmLv4EODp8YCn73YnXySP3p3XAYna2l+0IvwqlqI+sS0p6Pb4Zg fvS02sp3lTLOW8ZQIvTxVk93h8YQgRmdWmdXZe4INI2y/xPAGcCAN6o7Ctvy43sh x8kd6Aum1x3IUPnrNZOUg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrfeeltddgjeejucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvfevuffkgggtugesghdtreertddtjeenucfhrhhomhepofgrrhgvkhcu ofgrrhgtiiihkhhofihskhhiqdfikphrvggtkhhiuceomhgrrhhmrghrvghksehinhhvih hsihgslhgvthhhihhnghhslhgrsgdrtghomheqnecuggftrfgrthhtvghrnhephefguedv jeekieekleduleetveefgeffgeetfeffteehteffuddujeeuudfgvdetnecuffhomhgrih hnpehquhgsvghsqdhoshdrohhrghdpghhithhhuhgsrdgtohhmnecuvehluhhsthgvrhfu ihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepmhgrrhhmrghrvghksehinhhvih hsihgslhgvthhhihhnghhslhgrsgdrtghomh X-ME-Proxy: Feedback-ID: i1568416f:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 17 Oct 2022 23:52:19 -0400 (EDT) Date: Tue, 18 Oct 2022 05:52:16 +0200 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Christoph Hellwig , Konrad Rzeszutek Wilk , Anshuman Khandual Cc: Juergen Gross , Stefano Stabellini , Oleksandr Tyshchenko , regressions@lists.linux.dev, xen-devel@lists.xenproject.org, iommu@lists.linux.dev Subject: i915 "GPU HANG", bisected to a2daa27c0c61 "swiotlb: simplify swiotlb_max_segment" Message-ID: Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="cFcJRBMRCFbBRw5w" Content-Disposition: inline --cFcJRBMRCFbBRw5w Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Date: Tue, 18 Oct 2022 05:52:16 +0200 From: Marek =?utf-8?Q?Marczykowski-G=C3=B3recki?= To: Christoph Hellwig , Konrad Rzeszutek Wilk , Anshuman Khandual Cc: Juergen Gross , Stefano Stabellini , Oleksandr Tyshchenko , regressions@lists.linux.dev, xen-devel@lists.xenproject.org, iommu@lists.linux.dev Subject: i915 "GPU HANG", bisected to a2daa27c0c61 "swiotlb: simplify swiotlb_max_segment" Hi, Since 5.19, I observe severe glitches (mostly horizontal black stripes, but not only) when using IGD in Xen PV dom0. After not very long time Xorg crashes, and dmesg contain messages like this: i915 0000:00:02.0: [drm] GPU HANG: ecode 7:1:01fffbfe, in Xorg [5337] i915 0000:00:02.0: [drm] Resetting rcs0 for stopped heartbeat on rcs0 i915 0000:00:02.0: [drm] Xorg[5337] context reset due to GPU hang The issue can be observed on several different hardware (at least Ivy Bridge, Tiger Lake and Kaby Lake). It doesn't always happen immediately, sometimes I need to start several VMs first. Example how it looks like: https://openqa.qubes-os.org/tests/48187#step/qui_widgets_notifications/8 More screenshots and logs are linked at https://github.com/QubesOS/qubes-is= sues/issues/7813 I managed to git bisect the issue and ended up with this as the first bad commit: commit a2daa27c0c6137481226aee5b3136e453c642929 Author: Christoph Hellwig Date: Mon Feb 14 11:44:42 2022 +0100 swiotlb: simplify swiotlb_max_segment =20 Remove the bogus Xen override that was usually larger than the actu= al size and just calculate the value on demand. Note that swiotlb_max_segment still doesn't make sense as an interface and sh= ould eventually be removed. =20 Signed-off-by: Christoph Hellwig Reviewed-by: Anshuman Khandual Reviewed-by: Konrad Rzeszutek Wilk Tested-by: Boris Ostrovsky I tried reverting just this commit on top of 6.0.x, but the context changed significantly in subsequent commits, so after trying reverting it together with 3 or 4 more commits I gave up. What may be an important detail, the system heavily uses cross-VM shared memory (gntdev) to map window contents from VMs. This is Qubes OS, and it uses Xen 4.14. --=20 Best Regards, Marek Marczykowski-G=C3=B3recki Invisible Things Lab --cFcJRBMRCFbBRw5w Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhrpukzGPukRmQqkK24/THMrX1ywFAmNOIvEACgkQ24/THMrX 1yycxQf+MDrI5t+yoFuj1FC3BntpCUVQRQlOwZpAQuuDMEZp7i0SQgELI+rr7AxM 7hENZvEWiRVfcul01QkAIqJHtuNtRCjdIZre5ISRBsqgw8KHyD7SWxGcs9hsXOcU Z5r1dIX8FqROun1vYIhRVBOtIHIA1jXnHEttenNu2KnMEXstGU03X+Xri99PJPH/ JaYf+re4ziOqYqWE6SkQlmo2iDVOIbbg9huOJTFjRBf4VCVQM3jMIh87i52V+U9W vhxvGK8cYRRo4DWQOdgNRMCqKG9w0xn2uB06E2KXqwenNv++EhWEQNCeR13otXY5 Hh6jT1pbY3q76EOTjIYfvL5Pi0MXvA== =3u4/ -----END PGP SIGNATURE----- --cFcJRBMRCFbBRw5w--