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 4AB4CD1D87B for ; Tue, 15 Oct 2024 16:07:17 +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=l6VKTTEot+K7niCJS6lBnaCocYaIc0vO9Sx2qrc2It0=; b=T1CrBjb0NBMtYBF6qiwCkeRoDm g3DIqjw5C8hQpNA65sQA0VhexEOpkIZ//NE60yqHk6anfuNI0Nqjdb2/cJ8xEAXqyANFk6lU6QbHk lqxIA4qT+rKRKWfSYBpcOkvEIUHy1zXBXkZA/8FidSp8OhOnVVrRNhyTMafdQKraEaD/LmDd4TfWP CbbgBzdcGaMKOk3frdf7GUht2gq5yLh2nr//qtBmkTfZ0HabUi1suPf8EwvcoZVqw7zCkaBfiyTji zaGWH2RMCM40D+5i/wbOnBacPYU+vlwzu//EHnCj49MlkTP+0QBsR6zcr6yLU5yA5qtKQY2owBQ2P ApBFcm/Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t0k4b-00000008pCE-2FnR; Tue, 15 Oct 2024 16:07:01 +0000 Received: from out-182.mta1.migadu.com ([2001:41d0:203:375::b6]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t0k3A-00000008p08-2fzH for linux-arm-kernel@lists.infradead.org; Tue, 15 Oct 2024 16:05:34 +0000 Date: Tue, 15 Oct 2024 09:05:18 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1729008327; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=l6VKTTEot+K7niCJS6lBnaCocYaIc0vO9Sx2qrc2It0=; b=T7Ng6TJCI19EPEOMr+JCbwLaGP6CGCut2IkXEyXDqtYZ0tGbxnoY7SetkIYlsQ7wEly95u RO/WKJKryq5K1tEDqPmR6031gcDsDG5R8DbAXNQUCtI/JIcDqKxdfTBah9MtBhoYxyNFGy 2fOs8s6cC3zmRL0Vc8+HrHvHMGJGaR4= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: David Woodhouse Cc: Paolo Bonzini , Jonathan Corbet , Marc Zyngier , James Morse , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Rutland , Lorenzo Pieralisi , "Rafael J. Wysocki" , Pavel Machek , Len Brown , Shuah Khan , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-pm@vger.kernel.org, linux-kselftest@vger.kernel.org, Francesco Lavra , Miguel Luis Subject: Re: [PATCH v5 4/5] KVM: selftests: Add test for PSCI SYSTEM_OFF2 Message-ID: References: <20240926184546.833516-1-dwmw2@infradead.org> <20240926184546.833516-5-dwmw2@infradead.org> <408b137dbf60ff4d189cbd98b7cf8cd833579f61.camel@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <408b137dbf60ff4d189cbd98b7cf8cd833579f61.camel@infradead.org> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241015_090533_110488_912EA1DB X-CRM114-Status: GOOD ( 33.68 ) 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 Sat, Oct 12, 2024 at 10:28:10AM +0100, David Woodhouse wrote: > On Tue, 2024-10-01 at 08:33 -0700, Oliver Upton wrote: > > On Thu, Sep 26, 2024 at 07:37:59PM +0100, David Woodhouse wrote: > > > +       vm = setup_vm(guest_test_system_off2, &source, &target); > > > +       vcpu_get_reg(target, KVM_REG_ARM_PSCI_VERSION, &psci_version); > > > +       TEST_ASSERT(psci_version >= PSCI_VERSION(0, 2), > > > +                   "Unexpected PSCI version %lu.%lu", > > > +                   PSCI_VERSION_MAJOR(psci_version), > > > +                   PSCI_VERSION_MINOR(psci_version)); > > > + > > > +       if (psci_version < PSCI_VERSION(1,3)) > > > +               goto skip; > > > > I'm not following this. Is there a particular reason why we'd want to > > skip for v1.2 and fail the test for anything less than that? > > These tests unconditionally set KVM_ARM_VCPU_PSCI_0_2 in setup_vm(). > Which is probably OK assuming support for that that predates > KVM_CAP_ARM_SYSTEM_SUSPEND (which is already a TEST_REQUIRE() right at > the start). > > So the world is very broken if KVM actually starts a VM but the version > isn't at least 0.2, and it seemed like it warranted an actual failure. If we're looking at this from a testing lens then KVM coming up with any PSCI version other than KVM_ARM_PSCI_LATEST (i.e. v1.3) is a bug. So maybe we can tighten that assertion because... > > Just do TEST_REQUIRE(psci_version >= PSCI_VERSION(1, 3)), it makes the > > requirements obvious in the case someone runs new selftests on an old > > kernel. > > I don't think we want to put that in main() and skip the other checks > that would run on earlier kernels. Running KVM selftests on older kernels in a meaningful way isn't something we support. At all. An example of this is commit 8a53e1302133 ("KVM: selftests: Require KVM_CAP_USER_MEMORY2 for tests that create memslots"), which skips ~everything for kernels older than 6.8. > (Even if we had easy access to > psci_version without actually running a test and starting a VM). > > I could put it into host_test_system_off2() which runs last (and > comment the invocations in main() to say that they're in increasing > order of PSCI version) to accommodate such). But then it seems that I'd > be the target of this comment in ksft_exit_skip()... > > /* > * FIXME: several tests misuse ksft_exit_skip so produce > * something sensible if some tests have already been run > * or a plan has been printed. Those tests should use > * ksft_test_result_skip or ksft_exit_fail_msg instead. > */ > > I suspect the real answer here is that the individual tests here be > calling ksft_test_result_pass(), and the system_off2 one should call > ksft_test_result_skip() if it skips? modulo a few one-offs, KVM selftests doesn't use the kselftest harness so it isn't subject to this comment. Since there's no test plan, we can skip at any time. > I'll add an explicit comment about the 0.2 check though, saying that it > should never happen so we might as well have the ASSERT for it. After looking at this again, I think we should do one of the following: - TEST_REQUIRE() that the PSCI version is at least v1.3, making the dependency clear on older kernels. - TEST_REQUIRE() for v1.3, which would provide better test coverage on upstream. -- Thanks, Oliver