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 8B76CC0218F for ; Wed, 29 Jan 2025 18:04:51 +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:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=E4qYr+BfI2d97uSVNI+YmBvuCgLID4BAS+wE8al32eY=; b=ltlIYpAJy7fN3vj89qhQHvF226 bO+s0MnPMqfRzAwBKP1b1N/+brxqBKkoXlRXJe5kfH/AGwDYkxyQuh+0vokTua6fkJ8p1SALZSEUO mtcmVwVIJdE7JtSNtqvDvTW5qKpT6kwFcqCkqQyCC9lG73yAEozcJ9G+fJxZBW1aiwtYuX202z5lq dXGzXJp5jFIHy5ueEPqYzPcrVwYFEnL9fdk/vwEmDTEQG5WRZaeH525i8duoUR/ansoCeinvn93j4 zpUlbb4beKU2SwEEKgNsDL4AJ3mfpm7oRwZ5TI7LnRFczBSddo4HUIoVOGyFURPo0/LP3zVosP5Nq ebsCaK4w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tdCQW-00000007ZKP-2w1E; Wed, 29 Jan 2025 18:04:36 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tdCP9-00000007ZDf-0OxV for linux-arm-kernel@lists.infradead.org; Wed, 29 Jan 2025 18:03:16 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id F0CCF5C5E32; Wed, 29 Jan 2025 18:02:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88272C4CED1; Wed, 29 Jan 2025 18:03:07 +0000 (UTC) Date: Wed, 29 Jan 2025 18:03:05 +0000 From: Catalin Marinas To: Anshuman Khandual Cc: Rob Herring , Marc Zyngier , linux-arm-kernel@lists.infradead.org, Will Deacon , Ryan Roberts , Mark Rutland , Oliver Upton , Jonathan Corbet , Eric Auger , kvmarm@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/7] arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9 Message-ID: References: <20241220072240.1003352-1-anshuman.khandual@arm.com> <20250102160402.GB3990035-robh@kernel.org> <86wmf5wo8u.wl-maz@kernel.org> <7f5c68c7-8036-4d18-950f-80e55ac8ea11@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <7f5c68c7-8036-4d18-950f-80e55ac8ea11@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250129_100311_184255_D1E6F21D X-CRM114-Status: GOOD ( 20.70 ) 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 Tue, Jan 28, 2025 at 02:41:17PM +0530, Anshuman Khandual wrote: > On 1/18/25 03:37, Rob Herring wrote: > > On Thu, Jan 16, 2025 at 9:32 AM Catalin Marinas wrote: > >> > >> On Wed, Jan 08, 2025 at 07:47:16AM -0600, Rob Herring wrote: > >>> On Wed, Jan 8, 2025 at 5:15 AM Marc Zyngier wrote: > >>>> On Tue, 07 Jan 2025 22:13:47 +0000, > >>>> Rob Herring wrote: > >>>>> On Tue, Jan 7, 2025 at 6:13 AM Catalin Marinas wrote: > >>>>>> But does KVM actually expose the feature to EL1 in ID_AA64DFR1_EL1 and > >>>>>> than traps it at EL2? > >>>>> > >>>>> As Marc pointed out KVM only advertises PMUv3.8. Regardless, guest > >>>>> accesses to these registers are trapped with or without this series. > >>>> > >>>> And most probably generates a nice splat in the kernel log, as nobody > >>>> updated KVM to handle *correctly* PMICNTR_EL0 traps, let alone deal > >>>> with the FGT2 registers. > >>> > >>> Isn't that this series[1]? Should that have come first, I guess I know > >>> that *now*. > >> [...] > >>> [1] https://lore.kernel.org/all/20241210055311.780688-1-anshuman.khandual@arm.com/ > >> > >> It's not any clearer to me. Does this series depend on the 46-patch one? > >> Or, if we had the other, is this no longer needed? Or none of these, > >> they are independent. > > > > They are independent. I think ideally we'd want everything landing at > > the same time, but we're past ideal at this point. Without this > > series, if someone uses PMU on v8.9 and firmware enabled FGT2, then > > the kernel will crash. Without the above series, KVM will have > > warnings in the kernel log, but otherwise function. > > Right, they are independent. Just that Rob had observed this PMU v3.8 boot > requirement while reviewing the HW breakpoint series earlier. I should just > respin this series after the upcoming v6.14-rc1 release is out ? They may apply cleanly but please do rebase and repost at -rc1. Thanks. -- Catalin