From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 5EDCD1E0DDC for ; Tue, 11 Mar 2025 07:28:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741678098; cv=none; b=ZApD+Dk3lGSblgdSirUanKGmV3aJ0IEgOE/RIftygmNBc0GfaPDZJpAjZB2G5H3mj6AU1OK0OnlKvOGWLAAaHWpRsnUU3Jiuu/45MDu73jDUL4yK4KhpyJZFoJwV8pYCkVRES5S2BLak0nHn6ngY8Mxw8cUik3i8LK2YXCvWjuw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741678098; c=relaxed/simple; bh=cDeaKhsAblOqbe1pQfxWDuLhNshQnyKnykqiFdidVYs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UglmhKfwpYEDdBftZHK1mjzOdOspp4Fl+gNuKhQkhpOeJmiNLPuhwLWgVobv/e5aCla25TpI3PSy/94tkrYpba6485DMOqW1XBCnmg1L9LDN+YxB78Y2WEMkYs08V0PnOMgftif6GlmXfuTk92kCeAJ0tT03CDPiNnr5PK0xQlM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t35DdyXS; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="t35DdyXS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA7C7C4CEE9; Tue, 11 Mar 2025 07:28:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741678096; bh=cDeaKhsAblOqbe1pQfxWDuLhNshQnyKnykqiFdidVYs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=t35DdyXSdyDN7wDspuyXbyGcBe8rDdR0PGDwxtuwpYaq+s9ExXFHNNpudQanlkHm0 ZGq5NARqiFQoUYsqiOCvFqwx8VvWqm+ogioT2ZuuXn03vqUBcFOqB52QZkB4Rwemnf 92Un0HABjmEq4G2UtCNgsHUfWTJTMVoa7ueXCLtIf6bMx9dozWV7VcYmjajHIwEQsK XIs/J52gOZKxqn6fu2l0Tq0cjx/1tfPw0Y2bjkcaPD3WG5nO8wPwoB+2IPjUxROpBh uw6+QNaVPPBg8TmXXHOMHFuLcI+aDu3c41zOCOyqumrCExYLoYksxwOq2imc+waHKd E2z+w+G4YKucg== Date: Tue, 11 Mar 2025 08:28:12 +0100 From: Ingo Molnar To: Balbir Singh Cc: Bert Karwatzki , Kees Cook , Bjorn Helgaas , Linus Torvalds , Peter Zijlstra , Andy Lutomirski , linux-kernel@vger.kernel.org Subject: Re: commit 7ffb791423c7 breaks steam game Message-ID: References: <20250310112206.4168-1-spasswolf@web.de> <951f9d13-72e4-41c3-9ace-8639e2a9485d@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: * Balbir Singh wrote: > On 3/11/25 08:48, Balbir Singh wrote: > > On 3/10/25 22:22, Bert Karwatzki wrote: > >> Using linux next-20250307 to play the game stellaris via steam I noticed that > >> loading the game gets sluggish with the progress bar getting stuck at 100%. > >> In this situation mouse and keyboard inputs don't work properly anymore. > >> Switching to a VT and killing stellaris somewhat fixes the situation though in > >> one instance the touchpad did not work after that. I bisected this between > >> v6.14-rc5 and next-20250307 and got this as the first bad commit: > >> > >> 7ffb791423c7c518269a9aad35039ef824a40adb is the first bad commit > >> commit 7ffb791423c7c518269a9aad35039ef824a40adb (HEAD) > >> Author: Balbir Singh > >> Date: Fri Feb 7 10:42:34 2025 +1100 > >> > >> x86/kaslr: Reduce KASLR entropy on most x86 systems > >> > >> Reverting commit 7ffb791423c7 in next-20250307 fixes the issue for me. > >> > > > > Thanks for the report! Could you also share the dmesg? Do you have any proprietary > > modules loaded? Could you also share the output of /proc/iomem (captured as sudo)? > > The lspci output is useful, lspci -vvv (captured with sudo) would help see where > > the BAR regions are, specifically before and after the patch. Could you also share > > the kernel config? > > > > I assume your config has CONFIG_PCI_P2PDMA enabled. Did the system ever work with > > nokaslr for you? > > > > I am a little surprised that reducing the entropy causes these issues and having > > a larger direct map causes these issues. > > Hi, Bert > > I tried to reproduce the issue at my end, but could not. I am new to Steam and my > hardware/games are also different. From what I could gather, Steam is a 32 bit > application that uses SDL. For my testing I used Xorg, not wayland > > In addition to the above? > > 1. Could you confirm if the mouse/keyboard work outside of Steam? > 2. Does evtest /dev/input/ show anything? > 3. We could run the kernel with nokaslr and see if the issue reproduces? > 4. As a test, we could try disabling CONFIG_PCI_P2PDMA in the kernel config, > build boot and test, this has the same effect has not having the patch [ Just a side note: disabling CONFIG_PCI_P2PDMA will have the same effect *on KASRL* memory layout as reverting 7ffb791423c, but disabling support for the P2P DMA PCI feature may have other side effects. ] Thanks, Ingo