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 1C0E620B21F for ; Thu, 12 Dec 2024 07:58:01 +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=1733990282; cv=none; b=Vgc6Ia7mvcDKIk+ppbbpYpMWVyRV5jX9HUeQg0E+To44M9uVdvGtTBdiVkjlOsEjmNHdmw7DZnSewqlNHziP5v0A5xLuLpN77ZQxp9BuPxOI3LZFZbiQpfgx3JhMIjPAJqgMlw9kT57iS2AROj7FdzlwOpkWJGnnqHG3IE7iUEU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733990282; c=relaxed/simple; bh=heTP8tw+ZcZqUJG3MUscB12GOrn8+k8zURC8CKYj6hk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ODmXMjntbdh3eYmdq/zjryy3rb01rsV7tlInDqw12ZFBLndtgl7TXPJrkXbEEPujBHkvrQOdxpSS9kTlpILuLza4x2mvn12go0SOFpPMjTZ9irXuU7f1A54uPwwSDy85JDZVJDGmKBIG4A1fis3EEIqwSoRZPlaHbZ6MQ/mcmmg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=G19mhfbR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="G19mhfbR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9DBEC4CECE; Thu, 12 Dec 2024 07:58:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1733990281; bh=heTP8tw+ZcZqUJG3MUscB12GOrn8+k8zURC8CKYj6hk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=G19mhfbRPAaexSMh+j1NOkDSvdNU1VQRHQjvzorXkEyy1HFB8G/xvi1c+MyE8YN9B 8vGHUva0JoBWL3/HvzRehbeZsTEqsPRnRK66AziqQNfjIE1Wph0taeo2r7yu5PH2gz HYJoC9LHMeklETPWQL0NNC6jtbpnU9mdK4MgCJQQ= Date: Thu, 12 Dec 2024 08:57:58 +0100 From: Greg KH To: Raghavendra Rao Ananta Cc: stable@vger.kernel.org, Oliver Upton , Marc Zyngier Subject: Re: [PATCH] KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow status Message-ID: <2024121244-mannish-hermit-526d@gregkh> References: <2024120223-stunner-letter-9d09@gregkh> <20241203190236.2711302-1-rananta@google.com> Precedence: bulk X-Mailing-List: stable@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: <20241203190236.2711302-1-rananta@google.com> On Tue, Dec 03, 2024 at 07:02:36PM +0000, Raghavendra Rao Ananta wrote: > commit 54bbee190d42166209185d89070c58a343bf514b upstream. > > DDI0487K.a D13.3.1 describes the PMU overflow condition, which evaluates > to true if any counter's global enable (PMCR_EL0.E), overflow flag > (PMOVSSET_EL0[n]), and interrupt enable (PMINTENSET_EL1[n]) are all 1. > Of note, this does not require a counter to be enabled > (i.e. PMCNTENSET_EL0[n] = 1) to generate an overflow. > > Align kvm_pmu_overflow_status() with the reality of the architecture > and stop using PMCNTENSET_EL0 as part of the overflow condition. The > bug was discovered while running an SBSA PMU test [*], which only sets > PMCR.E, PMOVSSET<0>, PMINTENSET<0>, and expects an overflow interrupt. > > Cc: stable@vger.kernel.org > Fixes: 76d883c4e640 ("arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR register") > Link: https://github.com/ARM-software/sbsa-acs/blob/master/test_pool/pmu/operating_system/test_pmu001.c > Signed-off-by: Raghavendra Rao Ananta > [ oliver: massaged changelog ] > Reviewed-by: Marc Zyngier > Link: https://lore.kernel.org/r/20241120005230.2335682-2-oliver.upton@linux.dev > Signed-off-by: Oliver Upton > --- > virt/kvm/arm/pmu.c | 1 - > 1 file changed, 1 deletion(-) What branch is this patch for? thanks, greg k-h