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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AEDC6C4338F for ; Thu, 19 Aug 2021 08:19:03 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 22A246113B for ; Thu, 19 Aug 2021 08:19:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 22A246113B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id B66B44B10E; Thu, 19 Aug 2021 04:19:02 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id E8d1U-yYtADx; Thu, 19 Aug 2021 04:18:58 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 51DDA4B10F; Thu, 19 Aug 2021 04:18:58 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 0E6EB4B10D for ; Thu, 19 Aug 2021 04:18:57 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VwJX2rHwsPpy for ; Thu, 19 Aug 2021 04:18:56 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 11C764B10C for ; Thu, 19 Aug 2021 04:18:56 -0400 (EDT) Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 177B061139; Thu, 19 Aug 2021 08:18:55 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mGdGG-005vQx-SX; Thu, 19 Aug 2021 09:18:53 +0100 From: Marc Zyngier To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, Oliver Upton Subject: Re: [PATCH v2 0/4] KVM: arm64: Fix some races in CPU_ON PSCI call Date: Thu, 19 Aug 2021 09:18:49 +0100 Message-Id: <162936111407.541676.11774865845630227247.b4-ty@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210818202133.1106786-1-oupton@google.com> References: <20210818202133.1106786-1-oupton@google.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, oupton@google.com, suzuki.poulose@arm.com, james.morse@arm.com, ricarkol@google.com, alexandru.elisei@arm.com, drjones@redhat.com, jingzhangos@google.com, rananta@google.com, pshier@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Cc: Peter Shier , Raghavendra Rao Anata X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On Wed, 18 Aug 2021 20:21:29 +0000, Oliver Upton wrote: > The CPU_ON PSCI call requires careful coordination between vCPUs in KVM, > as it allows callers to send a payload (pc, context id) to another vCPU > to start execution. There are a couple of races in the handling of > CPU_ON: > > - KVM uses the kvm->lock to serialize the write-side of a vCPU's reset > state. However, kvm_vcpu_reset() doesn't take the lock on the > read-size, meaning the vCPU could be reset with interleaved state > from two separate CPU_ON calls. > > [...] Applied to next, thanks! [1/4] KVM: arm64: Fix read-side race on updates to vcpu reset state commit: 6654f9dfcb88fea3b9affc180dc3c04333d0f306 [2/4] KVM: arm64: Handle PSCI resets before userspace touches vCPU state commit: 6826c6849b46aaa91300201213701eb861af4ba0 [3/4] KVM: arm64: Enforce reserved bits for PSCI target affinities commit: e10ecb4d6c0761ca545b3946df1707a41f9f845e [4/4] selftests: KVM: Introduce psci_cpu_on_test commit: cb97cf95c44021278b7637731bc0928026bc29ab Cheers, M. -- Without deviation from the norm, progress is not possible. _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8636C4338F for ; Thu, 19 Aug 2021 08:19:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8971761139 for ; Thu, 19 Aug 2021 08:19:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237151AbhHSIUE (ORCPT ); Thu, 19 Aug 2021 04:20:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:45230 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237160AbhHSITa (ORCPT ); Thu, 19 Aug 2021 04:19:30 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 177B061139; Thu, 19 Aug 2021 08:18:55 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mGdGG-005vQx-SX; Thu, 19 Aug 2021 09:18:53 +0100 From: Marc Zyngier To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, Oliver Upton Cc: Suzuki K Poulose , James Morse , Ricardo Koller , Alexandru Elisei , Andrew Jones , Jing Zhang , Raghavendra Rao Anata , Peter Shier Subject: Re: [PATCH v2 0/4] KVM: arm64: Fix some races in CPU_ON PSCI call Date: Thu, 19 Aug 2021 09:18:49 +0100 Message-Id: <162936111407.541676.11774865845630227247.b4-ty@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210818202133.1106786-1-oupton@google.com> References: <20210818202133.1106786-1-oupton@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, oupton@google.com, suzuki.poulose@arm.com, james.morse@arm.com, ricarkol@google.com, alexandru.elisei@arm.com, drjones@redhat.com, jingzhangos@google.com, rananta@google.com, pshier@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, 18 Aug 2021 20:21:29 +0000, Oliver Upton wrote: > The CPU_ON PSCI call requires careful coordination between vCPUs in KVM, > as it allows callers to send a payload (pc, context id) to another vCPU > to start execution. There are a couple of races in the handling of > CPU_ON: > > - KVM uses the kvm->lock to serialize the write-side of a vCPU's reset > state. However, kvm_vcpu_reset() doesn't take the lock on the > read-size, meaning the vCPU could be reset with interleaved state > from two separate CPU_ON calls. > > [...] Applied to next, thanks! [1/4] KVM: arm64: Fix read-side race on updates to vcpu reset state commit: 6654f9dfcb88fea3b9affc180dc3c04333d0f306 [2/4] KVM: arm64: Handle PSCI resets before userspace touches vCPU state commit: 6826c6849b46aaa91300201213701eb861af4ba0 [3/4] KVM: arm64: Enforce reserved bits for PSCI target affinities commit: e10ecb4d6c0761ca545b3946df1707a41f9f845e [4/4] selftests: KVM: Introduce psci_cpu_on_test commit: cb97cf95c44021278b7637731bc0928026bc29ab Cheers, M. -- Without deviation from the norm, progress is not possible.