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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0782DC6FA82 for ; Tue, 20 Sep 2022 02:13:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230057AbiITCN2 (ORCPT ); Mon, 19 Sep 2022 22:13:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229921AbiITCN0 (ORCPT ); Mon, 19 Sep 2022 22:13:26 -0400 Received: from mail-vs1-xe2c.google.com (mail-vs1-xe2c.google.com [IPv6:2607:f8b0:4864:20::e2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6C7857544 for ; Mon, 19 Sep 2022 19:13:25 -0700 (PDT) Received: by mail-vs1-xe2c.google.com with SMTP id c3so1569729vsc.6 for ; Mon, 19 Sep 2022 19:13:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date; bh=LhprL2QVbzky7ZAXaXmKaCG2fZ/bG0UYXk9tOS7aXnY=; b=PGCJcjWLr4SHxMv8ivTAMamCPU/lkKK0dFqBEfZy+Xoh/g4UvHR8Tjalko7fnj29cf ECXwL9kH/aqs1iN4dEjp98ccsT9UZFvlEjmNb1ZOmBEMuslU7MeQ+dvTUeavKDHKQWkT Q4sdG5mzJs1M66f2/yOjLYV7Mr23g9I1tPE7KgDV5IWqbQPWUM6r7hi+cwY1VQ4e6HAG iYFfrDkQCOw8EuUPf0ygxePt4Cp2eXiDyNWgfI/4cE1WmmdejsR0gyunDCIeYe34a7rH /0OIP5YArMqkI2DI5zSGm4n52uKi+aoQYTAKw2OM/X8C/CcDvnsTdize+LSbiPaahbN2 sv7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date; bh=LhprL2QVbzky7ZAXaXmKaCG2fZ/bG0UYXk9tOS7aXnY=; b=yM/lMdVunsFesq+8miNd92Mk8p5ByuJI1xlmcCLcVef1A4BPp4K9McyB8INrg+1872 mZdXZ5g3T50dgEH2xQ0nRXmUnmqxYFS/Z/Dxijzf9hfi1KGhld2qxVE3lty+vDyrOvAD S1OmmeyPVVSfRwUlccsYEP3w5howRiRpRYaLBhPLLN/a53HqPIcD/Btd5qnLVsT5MwvS efp/SIqMPi3IY1mvAR58zf8xE/O8oOssAoXhjGZP6x3+ohsa4ET3EcB64LkZQ6xClA93 n9Ou6oY8GbsyL/137jUZkqB/bk2IiqzgnwusJiRqeedOQyO+0Ggre7/4Gjfn1tk0PLSE X2Pw== X-Gm-Message-State: ACrzQf0uNkrpjAlMQYM24EBZwtPTww1lPZ4xJCcGs8eLMeMf0MYvRFCA koBdmkXixhk9ErCJuFOEHkpeICE8i9VAcnUnAd+wcA== X-Google-Smtp-Source: AMsMyM7wgUY6E8j/4SMw+/72+ih55ve9ug7EcEf9GLIsdD3MXqyNwHc4oK+hZoFAn5gEb/6kdxZ6GEWk15PY0d04huI= X-Received: by 2002:a67:ea58:0:b0:38f:d89a:e4b3 with SMTP id r24-20020a67ea58000000b0038fd89ae4b3mr7517244vso.51.1663640004802; Mon, 19 Sep 2022 19:13:24 -0700 (PDT) MIME-Version: 1.0 References: <20220917010600.532642-1-reijiw@google.com> <20220917010600.532642-5-reijiw@google.com> <87bkrbln84.wl-maz@kernel.org> In-Reply-To: <87bkrbln84.wl-maz@kernel.org> From: Reiji Watanabe Date: Mon, 19 Sep 2022 19:13:08 -0700 Message-ID: Subject: Re: [PATCH v2 4/4] KVM: arm64: selftests: Add a test case for KVM_GUESTDBG_SINGLESTEP To: Marc Zyngier Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Linux ARM , James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Ricardo Koller , Oliver Upton , Jing Zhang , Raghavendra Rao Anata Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Marc, On Mon, Sep 19, 2022 at 2:36 AM Marc Zyngier wrote: > > On Sat, 17 Sep 2022 02:06:00 +0100, > Reiji Watanabe wrote: > > > > Add a test case for KVM_GUESTDBG_SINGLESTEP to the debug-exceptions test. > > The test enables single-step execution from userspace, and check if the > > exit to userspace occurs for each instruction that is stepped. > > Set the default number of the test iterations to a number of iterations > > sufficient to always reproduce the problem that the previous patch fixes > > on an Ampere Altra machine. > > A possibly more aggressive version of this test would be to force a > (short lived) timer to fire on the same CPU, forcing an exit. This > should hopefully result in a more predictable way to trigger the > issue. But that's a reasonable test as a start. Yes, that could result in a more predictable way to cause the specific case! I will consider this at a future opportunity. Thank you, Reiji 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 mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1524EC54EE9 for ; Tue, 20 Sep 2022 02:13:28 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 6219E4B658; Mon, 19 Sep 2022 22:13:28 -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 UpaI4C9vBsr0; Mon, 19 Sep 2022 22:13:27 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4C9CF4B62F; Mon, 19 Sep 2022 22:13:27 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 355744B615 for ; Mon, 19 Sep 2022 22:13:26 -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 3eM2A1uXWsVu for ; Mon, 19 Sep 2022 22:13:25 -0400 (EDT) Received: from mail-vs1-f45.google.com (mail-vs1-f45.google.com [209.85.217.45]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 527BE4B2A5 for ; Mon, 19 Sep 2022 22:13:25 -0400 (EDT) Received: by mail-vs1-f45.google.com with SMTP id q26so1563167vsr.7 for ; Mon, 19 Sep 2022 19:13:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date; bh=LhprL2QVbzky7ZAXaXmKaCG2fZ/bG0UYXk9tOS7aXnY=; b=PGCJcjWLr4SHxMv8ivTAMamCPU/lkKK0dFqBEfZy+Xoh/g4UvHR8Tjalko7fnj29cf ECXwL9kH/aqs1iN4dEjp98ccsT9UZFvlEjmNb1ZOmBEMuslU7MeQ+dvTUeavKDHKQWkT Q4sdG5mzJs1M66f2/yOjLYV7Mr23g9I1tPE7KgDV5IWqbQPWUM6r7hi+cwY1VQ4e6HAG iYFfrDkQCOw8EuUPf0ygxePt4Cp2eXiDyNWgfI/4cE1WmmdejsR0gyunDCIeYe34a7rH /0OIP5YArMqkI2DI5zSGm4n52uKi+aoQYTAKw2OM/X8C/CcDvnsTdize+LSbiPaahbN2 sv7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date; bh=LhprL2QVbzky7ZAXaXmKaCG2fZ/bG0UYXk9tOS7aXnY=; b=ToIIVlVnR+e69HR7QAN9124QbOROJY2l0NFDJ3uYqbz/3wdPpHQdkFkk+EMbKEF5Pa OVpWSTrQGfrl/Eq/IJJ6Mshpwh0/eRENxJyXlyfEr/1s1cbus3RBLbDMBo0pikJfQTmp B79bT3CCo3w+SUMxKU/wIEOKC4kEqHAoaEWOSkrL3c45Q9HntdbpgBluxp+63DURE0n0 XaWvgiyPze5u/R/oyMqF+02mXUZLUgzJGh/3B6hhSHQFDGYclp/tZjqleqFTscwH6n/y rczWbQODxq+y8asjScdkE8AKEWxpOItUwj3anmvVjy/AnrGwVFr3DTVNIyUoX/XzdpWw 79yQ== X-Gm-Message-State: ACrzQf04ai6bhHNYRNDpQQrUZfjLPth5wmm/OjXp+Ye7mkltLMjWGgVA PUxRunOKvFGtKhcGvmxQAKfB+EHKkq23Y5LFxkATAw== X-Google-Smtp-Source: AMsMyM7wgUY6E8j/4SMw+/72+ih55ve9ug7EcEf9GLIsdD3MXqyNwHc4oK+hZoFAn5gEb/6kdxZ6GEWk15PY0d04huI= X-Received: by 2002:a67:ea58:0:b0:38f:d89a:e4b3 with SMTP id r24-20020a67ea58000000b0038fd89ae4b3mr7517244vso.51.1663640004802; Mon, 19 Sep 2022 19:13:24 -0700 (PDT) MIME-Version: 1.0 References: <20220917010600.532642-1-reijiw@google.com> <20220917010600.532642-5-reijiw@google.com> <87bkrbln84.wl-maz@kernel.org> In-Reply-To: <87bkrbln84.wl-maz@kernel.org> From: Reiji Watanabe Date: Mon, 19 Sep 2022 19:13:08 -0700 Message-ID: Subject: Re: [PATCH v2 4/4] KVM: arm64: selftests: Add a test case for KVM_GUESTDBG_SINGLESTEP To: Marc Zyngier Cc: kvm@vger.kernel.org, Paolo Bonzini , kvmarm@lists.cs.columbia.edu, Linux ARM 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 Hi Marc, On Mon, Sep 19, 2022 at 2:36 AM Marc Zyngier wrote: > > On Sat, 17 Sep 2022 02:06:00 +0100, > Reiji Watanabe wrote: > > > > Add a test case for KVM_GUESTDBG_SINGLESTEP to the debug-exceptions test. > > The test enables single-step execution from userspace, and check if the > > exit to userspace occurs for each instruction that is stepped. > > Set the default number of the test iterations to a number of iterations > > sufficient to always reproduce the problem that the previous patch fixes > > on an Ampere Altra machine. > > A possibly more aggressive version of this test would be to force a > (short lived) timer to fire on the same CPU, forcing an exit. This > should hopefully result in a more predictable way to trigger the > issue. But that's a reasonable test as a start. Yes, that could result in a more predictable way to cause the specific case! I will consider this at a future opportunity. Thank you, Reiji _______________________________________________ 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 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 4002BC54EE9 for ; Tue, 20 Sep 2022 02:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; 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Mon, 19 Sep 2022 19:13:24 -0700 (PDT) MIME-Version: 1.0 References: <20220917010600.532642-1-reijiw@google.com> <20220917010600.532642-5-reijiw@google.com> <87bkrbln84.wl-maz@kernel.org> In-Reply-To: <87bkrbln84.wl-maz@kernel.org> From: Reiji Watanabe Date: Mon, 19 Sep 2022 19:13:08 -0700 Message-ID: Subject: Re: [PATCH v2 4/4] KVM: arm64: selftests: Add a test case for KVM_GUESTDBG_SINGLESTEP To: Marc Zyngier Cc: kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Linux ARM , James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Ricardo Koller , Oliver Upton , Jing Zhang , Raghavendra Rao Anata X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220919_191333_472220_B8FF7A30 X-CRM114-Status: GOOD ( 18.13 ) 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 Hi Marc, On Mon, Sep 19, 2022 at 2:36 AM Marc Zyngier wrote: > > On Sat, 17 Sep 2022 02:06:00 +0100, > Reiji Watanabe wrote: > > > > Add a test case for KVM_GUESTDBG_SINGLESTEP to the debug-exceptions test. > > The test enables single-step execution from userspace, and check if the > > exit to userspace occurs for each instruction that is stepped. > > Set the default number of the test iterations to a number of iterations > > sufficient to always reproduce the problem that the previous patch fixes > > on an Ampere Altra machine. > > A possibly more aggressive version of this test would be to force a > (short lived) timer to fire on the same CPU, forcing an exit. This > should hopefully result in a more predictable way to trigger the > issue. But that's a reasonable test as a start. Yes, that could result in a more predictable way to cause the specific case! I will consider this at a future opportunity. Thank you, Reiji _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel