From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f48.google.com (mail-wm1-f48.google.com [209.85.128.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 367C52C9D for ; Tue, 7 Dec 2021 18:30:19 +0000 (UTC) Received: by mail-wm1-f48.google.com with SMTP id i12so38990wmq.4 for ; Tue, 07 Dec 2021 10:30:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=P9Uwn09eYyyIwTRyGRWnTwTRM7dwnhKedDkxkKM4RXA=; b=eVOiso57lmaa7m0exq+juyzObkr5L3REVnX+YO49Sj24AMMpT+aAZD98kjqXWFeXdA uXzzbL1CKOGomq0M8Cataknysxcvm7aOEqqoeV8gnfVXi5NZS8pltkIW6cez8WKO5P8Z XhAtzzuBYgrKn8akByL4pB5ioq3Qh075yVfvI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=P9Uwn09eYyyIwTRyGRWnTwTRM7dwnhKedDkxkKM4RXA=; b=6vAun2UcprRfCd+0qnBSYQlzZr4bCZmAyHWlclgM4VMMYk6rOO5kziE91MJ1iHjXPl Qr+4TQ34upCTFYLOl6acQZEfLZM4yHfw71nFymgiNW+RtT5kOaLV3Z77D/B5bJpLzV5L B0kIlTmEUGDDZrVxomwGokCxO2/Z+yfOHsbuUnDUkhAp1zNhL/+7mvhVjeI/GYvV0fUI tI0h1MHja0ztnL8dA2zSJ07dP44Xnhx8PlMt7RyUF18bWBLKy4YyB431wF4V9EGd9eVD Q8DzkyzzcgHXxdi5+33Ks+9nUFnMIgvj3q0VYPKsOiaHJyZQzDlRCxtXZP5eX7a92J76 qriA== X-Gm-Message-State: AOAM531fZcdnh1BBzQ7mINKNw+/Y5VA9r4DXbSO2AT8quhp2GeM+xuY6 qmW46TQDV9gbjj0442KVfjcQiQ== X-Google-Smtp-Source: ABdhPJzJKxPmKfAmyPFfcG2dghRlQo23z//Ukr8GLwTiMK8XCD3uaZGjXhIFu+FfV6u7dTGIS5NT3w== X-Received: by 2002:a1c:a905:: with SMTP id s5mr9333034wme.150.1638901817985; Tue, 07 Dec 2021 10:30:17 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id 10sm688585wrb.75.2021.12.07.10.30.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Dec 2021 10:30:17 -0800 (PST) Date: Tue, 7 Dec 2021 19:30:15 +0100 From: Daniel Vetter To: Karol Herbst Cc: Christian =?iso-8859-1?Q?K=F6nig?= , regressions@lists.linux.dev, nouveau , dri-devel , Dan Moulding , regressions@leemhuis.info, Ben Skeggs , sf@sfritsch.de Subject: Re: [Nouveau] Regression in 5.15 in nouveau Message-ID: References: <5dafba25-5424-3fe2-5046-ae1d4320f9c1@leemhuis.info> <20211206183721.6495-1-dmoulding@me.com> <6f62bd8c-3a2c-e553-898c-d42fb1583208@amd.com> Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Operating-System: Linux phenom 5.10.0-8-amd64 On Tue, Dec 07, 2021 at 06:32:06PM +0100, Karol Herbst wrote: > On Tue, Dec 7, 2021 at 10:52 AM Christian König > wrote: > > > > Am 06.12.21 um 19:37 schrieb Dan Moulding: > > > On 04.12.21 17:40, Stefan Fritsch wrote: > > >> Hi, > > >> > > >> when updating from 5.14 to 5.15 on a system with NVIDIA GP108 [GeForce > > >> GT 1030] (NV138) and Ryzen 9 3900XT using kde/plasma on X (not wayland), > > >> there is a regression: There is now some annoying black flickering in > > >> some applications, for example thunderbird, firefox, or mpv. It mostly > > >> happens when scrolling or when playing video. Only the window of the > > >> application flickers, not the whole screen. But the flickering is not > > >> limited to the scrolled area: for example in firefox the url and > > >> bookmark bars flicker, too, not only the web site. I have bisected the > > >> issue to this commit: > > >> > > >> commit 3e1ad79bf66165bdb2baca3989f9227939241f11 (HEAD) > > > I have been experiencing this same issue since switching to 5.15. I > > > can confirm that reverting the above mentioned commit fixes the issue > > > for me. I'm on GP104 hardware (GeForce GTX 1070), also running KDE > > > Plasma on X. > > > > I'm still scratching my head what's going wrong here. > > > > Either we trigger some performance problem because we now wait twice for > > submissions or nouveau is doing something very nasty and not syncing > > it's memory accesses correctly. > > > > Attached is an only compile tested patch which might mitigate the first > > problem. > > > > But if it's the second then nouveau has a really nasty design issue here > > and somebody with more background on that driver design needs to take a > > look. > > > > Ben mentioned a few times that fences might be busted but we all have > no idea what's actually wrong. So it might be that your change is > indeed triggering something which was always broken or something else. Description sounds a bit like we're doing a clear before Xorg has had a chance to copy the pixmap to the frontbuffer perhaps? That would point to a fencing issue in userspace, and somehow ignoring fences ensures that the Xorg copy/blt completes before we get around to clearing stuff. I'm assuming we're rendering with glamour, so is nouveau relying on kernel implicit sync or doing it's own fencing in userspace? -Daniel > > > Please test if that patch changes anything. > > > > Thanks, > > Christian. > > > > > > > > Cheers, > > > > > > -- Dan > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch