From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D21364A8F for ; Tue, 23 Sep 2025 16:51:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758646314; cv=none; b=Zq2a9i4SQ7G4O1lk/UcqnueSNDWUpbMmEo4H/AcUuxEUi5yw4VGfypqjuTWDFIxK1DTd0jP0oXl/oT4gMuXavPTndX2/BICF0fKVXO3WiqF+t++Cr407XoA6Qq27ZqZvHMwcpVIYyew638LZQR6hte2aXfdJqvJefRWUaZGFSsQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758646314; c=relaxed/simple; bh=QxaQ7JYmW6SoppxdzNqff99uc2GQFsWJ8bkLHSqAb3s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ey09L40iyvVd/9a2mDCXcIS37isyDp8cjRJk+Ua/QANXTAU3tP4kvhZPlvvC3ruZWWH2zNHHsIDsFrT/JzsXGkc68OaLkwRJd5alZCVmI/L0jhN+q9S+L7riWic4lmQnyZu+DfGejkThHvSvEVDD3VOcKNA1HmOJ+RzfFJBxFfs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=LPSo4mPx; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="LPSo4mPx" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-244570600a1so979575ad.1 for ; Tue, 23 Sep 2025 09:51:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1758646312; x=1759251112; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=5ttBHw83mBBKei73n8M/BNwMGiua/BJVn53tHa2ocQk=; b=LPSo4mPxcQBmLX2AxfdVcoMChvv9qDL2eJYwQwycq+jojs8BLMYioEl7A0s1AzStOU d1TmKNfAHQxRHqOvcz899ft7JxAUkbqrwEEfAIP5wLseIZ0nbMAnmjoU1/vDzA8SsRgw FXVivT3g/rMK4pNlgzwuJWfgdDeizVh7Kakt2kDYR7IZTVCA+8selkmCxunsWoYhUjCL iJHBrbGMGceLDcB1Gfr4urQ77S9lftua0Q6YKPixXhEVwBtlmKLT4Bk0+UxX4tXIccPO oKMDOTvBERghPev+LEq+5UlYv75KZC3C0bARozsGDukQCUl+Vqm6nUwDZQ51DZbbqp3t jA2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758646312; x=1759251112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=5ttBHw83mBBKei73n8M/BNwMGiua/BJVn53tHa2ocQk=; b=AgAdL73Iw8gv28dmWmSmbgRtMguNbs4uIOuVKckz+vtSXnmIPyOw5JaKuBDATgFPAW Bo5zKkJZqE4RfXfM/gqv65eUK1usIlxcPHXHFPGoAYAUc2q4cKhVT310QgfFEfQPmaEM jKS7reNDnpHKz6Nur4CmqEVmT8OclztoL3hmwDPGYa2gFWMlCkHT1wtkPem9zmwtqojF 15QN9LBKInmPXkTFnRrmLEir4CZDq3fkXO5lpsrPRv7yAeplCdVVHogVFBbQ0U837lWr A2NzhSvjN4tjVYp8l8XHXmzbWIMBIUu57x8has/Z42YGPAA2Ob6Jl5yF4miHeVhbE3Si nwqg== X-Forwarded-Encrypted: i=1; AJvYcCXUsAxVoLQHZ1ib3uuItyjtZHVBV6QWkIm2lzgYWbAUNwPFcxKmDUxhTCEgBWwRzs/1JUB7yIey4fKr0gs=@vger.kernel.org X-Gm-Message-State: AOJu0Yz5LtV8YSgbDpUX3y3nvoOnn6I62mFkp6/oaRsq2X12JT8s/7hV E9ZfJk3FzCxDBuusBZwJCeoe0U8NQDIMFwIqapqB9FOOOLCbqlQ3xxrqRdTmZiMrRllEsS5VePl n3m4dSg== X-Google-Smtp-Source: AGHT+IErnPS2OUnE/M9s+uEMA4ws/sYHBVcLuOlMX+nidzjdFfhtmVnknKhA38KDZ5Q4wlGtCqW08/b9loo= X-Received: from pjp3.prod.google.com ([2002:a17:90b:55c3:b0:327:dc48:1406]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:2c04:b0:266:57f7:25f5 with SMTP id d9443c01a7336-27cd6c9dec5mr45739465ad.7.1758646312450; Tue, 23 Sep 2025 09:51:52 -0700 (PDT) Date: Tue, 23 Sep 2025 09:51:50 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250919223258.1604852-1-seanjc@google.com> <20250919223258.1604852-46-seanjc@google.com> Message-ID: Subject: Re: [PATCH v16 45/51] KVM: selftests: Add an MSR test to exercise guest/host and read/write From: Sean Christopherson To: Chao Gao Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Tom Lendacky , Mathias Krause , John Allen , Rick Edgecombe , Binbin Wu , Xiaoyao Li , Maxim Levitsky , Zhang Yi Z , Xin Li Content-Type: text/plain; charset="us-ascii" On Tue, Sep 23, 2025, Chao Gao wrote: > On Fri, Sep 19, 2025 at 03:32:52PM -0700, Sean Christopherson wrote: > >+ /* > >+ * TSC_AUX is supported if RDTSCP *or* RDPID is supported. Add > >+ * entries for each features so that TSC_AUX doesn't exists for > >+ * the "unsupported" vCPU, and obviously to test both cases. > >+ */ > >+ MSR_TEST2(MSR_TSC_AUX, 0x12345678, canonical_val, RDTSCP, RDPID), > >+ MSR_TEST2(MSR_TSC_AUX, 0x12345678, canonical_val, RDPID, RDTSCP), > > At first glance, it's unclear to me why canonical_val is invalid for > MSR_TSC_AUX, especially since it is valid for a few other MSRs in this > test. Should we add a note to the above comment? e.g., > > canonical_val is invalid for MSR_TSC_AUX because its high 32 bits must be 0. Yeah, I was being lazy. To-be-tested, but I'll squash this: diff --git a/tools/testing/selftests/kvm/x86/msrs_test.c b/tools/testing/selftests/kvm/x86/msrs_test.c index 9285cf51ef75..345a39030a0a 100644 --- a/tools/testing/selftests/kvm/x86/msrs_test.c +++ b/tools/testing/selftests/kvm/x86/msrs_test.c @@ -48,6 +48,13 @@ struct kvm_msr { */ static const u64 canonical_val = 0x123456789000ull; +/* + * Arbitrary value with bits set in every byte, but not all bits set. This is + * also a non-canonical value, but that's coincidental (any 64-bit value with + * an alternating 0s/1s pattern will be non-canonical). + */ +static const u64 u64_val = 0xaaaa5555aaaa5555ull; + #define MSR_TEST_CANONICAL(msr, feat) \ __MSR_TEST(msr, #msr, canonical_val, NONCANONICAL, 0, feat) @@ -247,8 +254,8 @@ static void test_msrs(void) * entries for each features so that TSC_AUX doesn't exists for * the "unsupported" vCPU, and obviously to test both cases. */ - MSR_TEST2(MSR_TSC_AUX, 0x12345678, canonical_val, RDTSCP, RDPID), - MSR_TEST2(MSR_TSC_AUX, 0x12345678, canonical_val, RDPID, RDTSCP), + MSR_TEST2(MSR_TSC_AUX, 0x12345678, u64_val, RDTSCP, RDPID), + MSR_TEST2(MSR_TSC_AUX, 0x12345678, u64_val, RDPID, RDTSCP), MSR_TEST(MSR_IA32_SYSENTER_CS, 0x1234, 0, NONE), /*