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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA0C4C433EF for ; Fri, 5 Nov 2021 01:34:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C81E56120F for ; Fri, 5 Nov 2021 01:34:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230353AbhKEBgu (ORCPT ); Thu, 4 Nov 2021 21:36:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229712AbhKEBgt (ORCPT ); Thu, 4 Nov 2021 21:36:49 -0400 Received: from mail-lj1-x236.google.com (mail-lj1-x236.google.com [IPv6:2a00:1450:4864:20::236]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F222FC061714 for ; Thu, 4 Nov 2021 18:34:10 -0700 (PDT) Received: by mail-lj1-x236.google.com with SMTP id a10so4999302ljk.13 for ; Thu, 04 Nov 2021 18:34:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=WmJtXBkg7pd+AkHNmF/OOE0ZCZ7A0DUPGQ3AraUyTKE=; b=PZE9AjSPOY3ehFs177/vcSypOeEzbZbOjJTIP6cW52S5WQTctkopZtXJ8ZzGpp4Ftk X7/NIPtm/J/5VDoXx/Rk8S8UZL1YO1x3EzWDIGTtxRfd4KPeefDpEsG1u8daXYp9AqG+ ERm34LdXlTc1oMG4MjN/+ZedoSmn6HMU7WNncJ0a8GhiBg++YuGmkY7sgeVTR00j4RQ0 O6F1zstzgn2wLez4WTmwyygFlygy6VJXxNUKxBD5N1w99YYS1i9l6C4f3/9/BZXVXFJQ TBdoEpu2mzZovHHUC9PY1QP0DRbm7upXKQkmiBMSgs9gUyFpby5JJ0PbegWFoAG8mCC9 tFUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=WmJtXBkg7pd+AkHNmF/OOE0ZCZ7A0DUPGQ3AraUyTKE=; b=hb8vHD/zVr6Yqo2znBd0THkVp1esksJ/sRiOMi8i9JVZcKyabvdoFrl75pqmlrNH+Z IpuM/5JgdHsY0BIAMo0pWBCKDZczBeQLkcaPZgzoXQ5/BO/2hHggswsZ8SOkclZ6ldZh VmUfJfwXSIzjSNtmGx8PqdTKGlTdDJp3bzN0IAYJkPLZKvr9NKz893w7cwCDOuY3SIZF Ak+H1Fr/HWaUJoe2FOpJXwNkY9+LyCEhow9wubrcCL1VQi6x9IIquPJSWKKMb20hQHvt jpvgpTfuZsDlEKdwll/L8vVbFsngdXMS0CIth/YsXLhx56nKOKqoRvd3vV0WAtyyQgnX BNmw== X-Gm-Message-State: AOAM533LG6K6YFbxFX66otWqjgsb7hyVewxIKNv+/rhOixfMNCfud71D h3XiyNJf8XbdvIki0I4OeuabSajD83FUaQNzqbbqjQ== X-Google-Smtp-Source: ABdhPJyewwZhYvIK3ydA+zOEsxVMwLZ6je5RssWrC6icEv9NcYFD1E5ThOQun0PMv8mV+NBDOBTesnHzih36VdxT/oQ= X-Received: by 2002:a05:651c:984:: with SMTP id b4mr8397659ljq.170.1636076049067; Thu, 04 Nov 2021 18:34:09 -0700 (PDT) MIME-Version: 1.0 References: <20211103062520.1445832-1-reijiw@google.com> <20211103062520.1445832-3-reijiw@google.com> In-Reply-To: From: Oliver Upton Date: Thu, 4 Nov 2021 18:33:58 -0700 Message-ID: Subject: Re: [RFC PATCH v2 02/28] KVM: arm64: Save ID registers' sanitized value per vCPU To: Reiji Watanabe Cc: Marc Zyngier , kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Will Deacon , Andrew Jones , Peng Liang , Peter Shier , Ricardo Koller , Jing Zhang , Raghavendra Rao Anata Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Nov 4, 2021 at 2:39 PM Reiji Watanabe wrote: > > Hi Oliver, > > On Thu, Nov 4, 2021 at 9:14 AM Oliver Upton wrote: > > > > Hi Reiji, > > > > On Tue, Nov 02, 2021 at 11:24:54PM -0700, Reiji Watanabe wrote: > > > Extend sys_regs[] of kvm_cpu_context for ID registers and save ID > > > registers' sanitized value in the array for the vCPU at the first > > > vCPU reset. Use the saved ones when ID registers are read by > > > userspace (via KVM_GET_ONE_REG) or the guest. > > > > Based on my understanding of the series, it appears that we require the > > CPU identity to be the same amongst all vCPUs in a VM. Is there any > > value in keeping a single copy in kvm_arch? > > Yes, that's a good point. > It reminded me that the idea bothered me after we discussed a similar > case about your counter offset patches, but I didn't seriously > consider that. Yeah, it was a good suggestion for the counter offsetting series, and one that I plan to adopt once I get back to that set :) -- Thanks, Oliver 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A4F7C433EF for ; Fri, 5 Nov 2021 01:34:16 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 79A8061245 for ; Fri, 5 Nov 2021 01:34:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 79A8061245 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com 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 0380C4B0BF; Thu, 4 Nov 2021 21:34:15 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com 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 bblC9qsQ65DA; Thu, 4 Nov 2021 21:34:13 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 8E4124B0BE; Thu, 4 Nov 2021 21:34:13 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id F21A54B0BE for ; Thu, 4 Nov 2021 21:34:11 -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 dHYUK2HJ2dP8 for ; Thu, 4 Nov 2021 21:34:10 -0400 (EDT) Received: from mail-lj1-f181.google.com (mail-lj1-f181.google.com [209.85.208.181]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 9DAE74A5A0 for ; Thu, 4 Nov 2021 21:34:10 -0400 (EDT) Received: by mail-lj1-f181.google.com with SMTP id t11so12492658ljh.6 for ; Thu, 04 Nov 2021 18:34:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=WmJtXBkg7pd+AkHNmF/OOE0ZCZ7A0DUPGQ3AraUyTKE=; b=PZE9AjSPOY3ehFs177/vcSypOeEzbZbOjJTIP6cW52S5WQTctkopZtXJ8ZzGpp4Ftk X7/NIPtm/J/5VDoXx/Rk8S8UZL1YO1x3EzWDIGTtxRfd4KPeefDpEsG1u8daXYp9AqG+ ERm34LdXlTc1oMG4MjN/+ZedoSmn6HMU7WNncJ0a8GhiBg++YuGmkY7sgeVTR00j4RQ0 O6F1zstzgn2wLez4WTmwyygFlygy6VJXxNUKxBD5N1w99YYS1i9l6C4f3/9/BZXVXFJQ TBdoEpu2mzZovHHUC9PY1QP0DRbm7upXKQkmiBMSgs9gUyFpby5JJ0PbegWFoAG8mCC9 tFUg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=WmJtXBkg7pd+AkHNmF/OOE0ZCZ7A0DUPGQ3AraUyTKE=; b=0mtlE3tkjFkJ5lhEbUS4/j1EE73t2mQ8Ir8iSVbLE21uIV+BF0RAYYVQ5kLNFiYrWy R4HTjWKIAFlISXNq6tjBX3z8D4oof80F5QlhF2ynuMGzLxMrt4OXx6m+4XSu/u30uCb7 4jNKbBtK8jZcJAlpsxGYllHE2TgJ65+EAOYHhChAYbN62qtvnC8g0YmROQwqsUWwyKEg NhF3DIo7ajV2OBeG0UL1BHjyiiU4kdulrh/q4EuKnKS/JNzEGsnaj83biX/EhdY7RmCY y2XOyJvSSzDdBxwP7XrEFZee8U4gwm+AeNEFntQ/hcmXpU0jmsDeN0rN2QkUkwhQlunI onXw== X-Gm-Message-State: AOAM531+G7UefEKF/uHQul6pUXzKuEnnuQQq3zRyX2hqe8HDorwF8ERN Q+P8hsxxkWh30W5bjeUzeBzZbVn9nnPMZzg9QjwKMg== X-Google-Smtp-Source: ABdhPJyewwZhYvIK3ydA+zOEsxVMwLZ6je5RssWrC6icEv9NcYFD1E5ThOQun0PMv8mV+NBDOBTesnHzih36VdxT/oQ= X-Received: by 2002:a05:651c:984:: with SMTP id b4mr8397659ljq.170.1636076049067; Thu, 04 Nov 2021 18:34:09 -0700 (PDT) MIME-Version: 1.0 References: <20211103062520.1445832-1-reijiw@google.com> <20211103062520.1445832-3-reijiw@google.com> In-Reply-To: From: Oliver Upton Date: Thu, 4 Nov 2021 18:33:58 -0700 Message-ID: Subject: Re: [RFC PATCH v2 02/28] KVM: arm64: Save ID registers' sanitized value per vCPU To: Reiji Watanabe Cc: kvm@vger.kernel.org, Marc Zyngier , Peter Shier , Will Deacon , Paolo Bonzini , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org 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 Thu, Nov 4, 2021 at 2:39 PM Reiji Watanabe wrote: > > Hi Oliver, > > On Thu, Nov 4, 2021 at 9:14 AM Oliver Upton wrote: > > > > Hi Reiji, > > > > On Tue, Nov 02, 2021 at 11:24:54PM -0700, Reiji Watanabe wrote: > > > Extend sys_regs[] of kvm_cpu_context for ID registers and save ID > > > registers' sanitized value in the array for the vCPU at the first > > > vCPU reset. Use the saved ones when ID registers are read by > > > userspace (via KVM_GET_ONE_REG) or the guest. > > > > Based on my understanding of the series, it appears that we require the > > CPU identity to be the same amongst all vCPUs in a VM. Is there any > > value in keeping a single copy in kvm_arch? > > Yes, that's a good point. > It reminded me that the idea bothered me after we discussed a similar > case about your counter offset patches, but I didn't seriously > consider that. Yeah, it was a good suggestion for the counter offsetting series, and one that I plan to adopt once I get back to that set :) -- Thanks, Oliver _______________________________________________ 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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4635DC433F5 for ; Fri, 5 Nov 2021 01:35:43 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id EB16261245 for ; Fri, 5 Nov 2021 01:35:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org EB16261245 Authentication-Results: mail.kernel.org; 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s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=WmJtXBkg7pd+AkHNmF/OOE0ZCZ7A0DUPGQ3AraUyTKE=; b=AirRsIZaiObuq7KyNl+8B+a0vzsJ4tMG0KMxIvPUFnOEhoa5G9Du9ghMPdL7PEe4G4 W9pBqvQg0r0aSx8wuT7En0x/n9VMoRccX7STZEQFwwECcmPin1g9N0YPjinqvBikcqLT xXwJTnYemyoqrCx18TIxUjhPMLC4nDQ1fXuK8flNRawtj6LyuwUZmPnh6ZAke/MNFQ9v r56kti6Hm7Yv7mOpfuzvTi/4ZkJkc1ZJ2VJ7VnSJMZ2cLI5gV7hIqdzApCklGwQvD4yN t6jQ7SMcmNmmi38q8wahKO6rRXPlIgsKaaW+M5gfYxnVNSDBtdtjhyWqEGeTjyPhBz0X GwRw== X-Gm-Message-State: AOAM531a2Pp81NxRf9VvjwI6WZlS2XkwoH21492dGhI5cdIUlEE4WHv2 3PxFj4VUVQ+3FJzVCkKtYSV8YlOGlFqpUSxE0Shxxw== X-Google-Smtp-Source: ABdhPJyewwZhYvIK3ydA+zOEsxVMwLZ6je5RssWrC6icEv9NcYFD1E5ThOQun0PMv8mV+NBDOBTesnHzih36VdxT/oQ= X-Received: by 2002:a05:651c:984:: with SMTP id b4mr8397659ljq.170.1636076049067; Thu, 04 Nov 2021 18:34:09 -0700 (PDT) MIME-Version: 1.0 References: <20211103062520.1445832-1-reijiw@google.com> <20211103062520.1445832-3-reijiw@google.com> In-Reply-To: From: Oliver Upton Date: Thu, 4 Nov 2021 18:33:58 -0700 Message-ID: Subject: Re: [RFC PATCH v2 02/28] KVM: arm64: Save ID registers' sanitized value per vCPU To: Reiji Watanabe Cc: Marc Zyngier , kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Will Deacon , Andrew Jones , Peng Liang , Peter Shier , Ricardo Koller , Jing Zhang , Raghavendra Rao Anata X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211104_183416_609952_9BBC5BC9 X-CRM114-Status: GOOD ( 18.81 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Nov 4, 2021 at 2:39 PM Reiji Watanabe wrote: > > Hi Oliver, > > On Thu, Nov 4, 2021 at 9:14 AM Oliver Upton wrote: > > > > Hi Reiji, > > > > On Tue, Nov 02, 2021 at 11:24:54PM -0700, Reiji Watanabe wrote: > > > Extend sys_regs[] of kvm_cpu_context for ID registers and save ID > > > registers' sanitized value in the array for the vCPU at the first > > > vCPU reset. Use the saved ones when ID registers are read by > > > userspace (via KVM_GET_ONE_REG) or the guest. > > > > Based on my understanding of the series, it appears that we require the > > CPU identity to be the same amongst all vCPUs in a VM. Is there any > > value in keeping a single copy in kvm_arch? > > Yes, that's a good point. > It reminded me that the idea bothered me after we discussed a similar > case about your counter offset patches, but I didn't seriously > consider that. Yeah, it was a good suggestion for the counter offsetting series, and one that I plan to adopt once I get back to that set :) -- Thanks, Oliver _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel