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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 3AB5EF55102 for ; Sat, 7 Mar 2026 19:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: References:In-Reply-To:Subject:Cc:To:From:Message-ID:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=zTb4E3pUzS6vEiYtanocqXEzVCCuozujnsHYdDNObA8=; b=sSCYWvINs09LmvV1M3NCcYffei n6gcUUbNNDtu0oAuPXxIyt05UeiRZi8zL4cBJdMTrKvxwP/TdVXCG2UgFlIjpaD2JOEHa11BZBBdn Idm567fYPeg859vXSUg+dwrFs7HOrgQjbEj5LWEqdwa6lnQZbo+P5af5Sr4MSjez/gpE1cPC3+Cwu dEv0gzvaR+NGsomW+qhCcICLHFcVzmj0sDWT8GU3kKOOyZLojh+PRn7hw78elYl30/ucWhoABLity dPbDk9nEtjQ5EDCDllq1omp4xit9l3xsZFBq4yLJuXiXxZMm81VrJVujPcYK7LPFLkateeIVs6VZR C7mNXJdA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyx2e-00000005Rdw-18AB; Sat, 07 Mar 2026 19:10:24 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vyx2c-00000005Rdq-10IB for linux-arm-kernel@lists.infradead.org; Sat, 07 Mar 2026 19:10:22 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 5461360053; Sat, 7 Mar 2026 19:10:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 026E4C19422; Sat, 7 Mar 2026 19:10:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772910621; bh=uKa6WLWDHwdq/7UThrztciV8wxtG930MrTaMOemvGkE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=D2yF8BInsXByWczjZiFjRH3ju0lQH6uX4PxVTlnhqSRbZI9JemF0HyZJn6AI9lMT9 WgFuBECLkplojEs2oCGawoUJxR53rY1iBrwGQDSgjW5WK2xeFswhe1DzUPckUtYc7u xnafL7oNEgE52k6VR3Pr/7lZFQjPc+k9+mZpGiiGu7FpAbEuWxB2Z+1valkrzSvOnW HeXslEVGw5nSGUJJDEDcIV5iK+BxXdw4lbnFAN/4kIJij1FkDDCLNpU1Mb5tyYeivK gmFX7ICTmB/l3lLopNBtKXo+WNxvEHRClSrzpEjROx66dzATM+J1B3V7IIxgNfGf1r wxtgvvldGHD/A== Received: from sofa.misterjones.org ([185.219.108.64] helo=lobster-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vyx2Y-0000000HDjs-1b7x; Sat, 07 Mar 2026 19:10:18 +0000 Date: Sat, 07 Mar 2026 19:10:17 +0000 Message-ID: <87y0k3cv6u.wl-maz@kernel.org> From: Marc Zyngier To: Valentine Burley Cc: "tabba" , "broonie" , "stable" , "oupton" , "joey.gouly" , "suzuki.poulose" , "yuzenghui" , "catalin.marinas" , "will" , "Sascha.Bischoff" , "sebott" , "linux-arm-kernel" , "kvmarm" , "linux-kernel" Subject: Re: [PATCH] KVM: arm64: Skip interrupts in LRs during EOIcount replay In-Reply-To: <19cc98f6bc6.30a0020a4990004.9101239855762576863@collabora.com> References: <20260307115955.369455-1-valentine.burley@collabora.com> <871phveh17.wl-maz@kernel.org> <19cc98f6bc6.30a0020a4990004.9101239855762576863@collabora.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: valentine.burley@collabora.com, tabba@google.com, broonie@kernel.org, stable@vger.kernel.org, oupton@kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, Sascha.Bischoff@arm.com, sebott@redhat.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, 07 Mar 2026 18:29:05 +0000, Valentine Burley wrote: > > Hi Marc, > > Thanks a lot for your reply. > > On Sat, 07 Mar 2026 17:33:08 +0100 Marc Zyngier wrote > > I can't reproduce it locally, but in a crap integration, where the GIC > > is clocked at a few dozen MHz, this is far more likely to happen. I > > should dig that Lazor out of the bin and put it back in the test rig. > > > > In retrospect, it is obvious. I just couldn't see it until then. Many > > thanks for going the extra mile and pointing out the core issue. > > Appreciate the clarification! > > We also have a few Lazor boards in our CI, and the Trogdors are indeed > legendary for hitting all kinds of edge cases. Right. Time to have a look at SBoyd's u-boot patches from last year! > > > > > Could you please give the hack below a go on your setup? It seems to > > work for me, but given that I never observed the issue the first > > place... > > I've tested this on my sc7180 Trogdor setup, and it completely > resolves the issue. The Cuttlefish VM now boots reliably. > > Tested-by: Valentine Burley Awesome. I have since tweaked the patch a tiny bit to keep the restart pointer per CPU instead of per vcpu, as this doesn't live beyond the load/put sequence. I'll post it formally for you to confirm that the updated version is still correct. Thanks, M. -- Jazz isn't dead. It just smells funny.