From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (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 E5F5D13E03E for ; Fri, 6 Sep 2024 21:15:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725657361; cv=none; b=eertUPRiYR4il+CWE/XrGG5A3EV0T0SuQAT2tu7IdG4w+XFn5ZmuV1+pbT3f2LygZZfqasXAJhA76N2M6KE4nmQ966b24TypwpF5xULqLJaVKc/ViFpG6qiXuBr90Ez3bnahyVFIoSIgiLm77afGckojrzZrYR28fG5hI6+kTqM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725657361; c=relaxed/simple; bh=eMxGOodtBW2fNQBcV/Vjo5HBI+UPeio/fR7QHQkm+0M=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=cQr1EGVzrM86zzo9yW33yxutWONL+BerZIArgyYwz9ZcEqe3cqDJyBdcDn6KStDwTpkzBCahn9aI5dzqZvtrZZWcfTpxinlIuhrQBYsIxWlz0aOuQvf1He9JGHJ9zVgDP0hzFY/LuFr4GMdr2Wt9E8Uz2EiL1LdKHdUXZfKX8WM= 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=ogfewqEJ; arc=none smtp.client-ip=209.85.219.202 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="ogfewqEJ" Received: by mail-yb1-f202.google.com with SMTP id 3f1490d57ef6-e0353b731b8so5948550276.2 for ; Fri, 06 Sep 2024 14:15:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1725657359; x=1726262159; 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=O0pikVsuPIymy9mQcsYH9buCVbx4mgvVE8xCp4ufTvM=; b=ogfewqEJY2lep2vTK8ylVwsd0cZ7PRTEwzMaDERa9GpKd2iJJbjacssJy0ulKFjMAN VIiNIBzznbOSk5TZEHauR3UsOKoqK6TBIM84z0gkurWzAkxZwUNY5Ky5Nza7e0iwRNo4 ta0b9ap/Gb70Bow9/Lwie70GmBXlsQ/DA7KrxF4O2DVFNA/VDvLI2l6DYnsZAShJuEHW R5kKuFjF/V1u8sfok3LM9p3uqVUFmaqfJ3690fMJIhpnwYj5SLR7L1869A7kbwV0x/yX 9L0we+DfckGA1mhWZD0dpQv5yjb3ZQtcbEMfVlPhvONjhk4BO2CT40KlHdd64IjdMkNh 8D8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725657359; x=1726262159; 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=O0pikVsuPIymy9mQcsYH9buCVbx4mgvVE8xCp4ufTvM=; b=YndC5lHexuXIMC4ide7SVY9AEYR2v4pxTLjyYY//RJSLN3Vref9aa3/t67MtBRh3Zd 807Ike0jw5R/nigED++JdWVOuOWoQOCJGo9sR3iJqH2jiho4163qLI4ddE9LYKdBhBAC zdClLMRw78gp0won1zawzGYpncobUHca4QVj0oE3pNYPFDHdwemy8t9r6dJyTaJk1RF2 V1PQMSR0wozeMBIaAWVf7p6f5DW/bQeyqa3iHO05vP0e+Gx8ugskM3mHPfeOhiQeKHcY niQcXzsPmtivuEtAQUgQNXSLqJnu5gqMc27QmAVd2u/ouKNM4y84VzA9PyUZWM5Pxq5c 3DRg== X-Forwarded-Encrypted: i=1; AJvYcCUYQDvtlI4qYiqoA2MEu+PwBv7qiYh0JqIyzn/ZFt7Qbh/TUj18YSfDvtlhrZzxaRvK6X4=@vger.kernel.org X-Gm-Message-State: AOJu0Yx58wusaOrqqglmwGDQjEpVe0mqdvJc2QilRwTfFMCE1eubl74z 5V18Iq87GPFWm0/neptdK7U3ZgH0vRJCvxyeyai0BnORLsKgpTYCuIGCXUPEBfOwY7PHXo+338d XtQ== X-Google-Smtp-Source: AGHT+IEhyXOb6ueTZoO2nNI//nUTPRUCj/uBjHhClAJ2CXjFjvXhugvAh2XP6oo8m69S1gMkq9KL2itwG4s= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a25:81cd:0:b0:e11:44fb:af26 with SMTP id 3f1490d57ef6-e1d3485d963mr6031276.2.1725657358725; Fri, 06 Sep 2024 14:15:58 -0700 (PDT) Date: Fri, 6 Sep 2024 14:15:57 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240902144219.3716974-1-erbse.13@gmx.de> Message-ID: Subject: Re: [PATCH] KVM: x86: Only advertise KVM_CAP_READONLY_MEM when supported by VM From: Sean Christopherson To: Shakeel Butt Cc: Tom Dohrmann , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Paolo Bonzini , Michael Roth Content-Type: text/plain; charset="us-ascii" On Fri, Sep 06, 2024, Shakeel Butt wrote: > On Mon, Sep 02, 2024 at 02:42:19PM GMT, Tom Dohrmann wrote: > > Until recently, KVM_CAP_READONLY_MEM was unconditionally supported on > > x86, but this is no longer the case for SEV-ES and SEV-SNP VMs. > > > > When KVM_CHECK_EXTENSION is invoked on a VM, only advertise > > KVM_CAP_READONLY_MEM when it's actually supported. > > > > Fixes: 66155de93bcf ("KVM: x86: Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX)") > > Cc: Sean Christopherson > > Cc: Paolo Bonzini > > Cc: Michael Roth > > Signed-off-by: Tom Dohrmann > > --- > > arch/x86/kvm/x86.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > > index 70219e406987..9ad7fe279e72 100644 > > --- a/arch/x86/kvm/x86.c > > +++ b/arch/x86/kvm/x86.c > > @@ -4656,7 +4656,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > > case KVM_CAP_ASYNC_PF_INT: > > case KVM_CAP_GET_TSC_KHZ: > > case KVM_CAP_KVMCLOCK_CTRL: > > - case KVM_CAP_READONLY_MEM: > > case KVM_CAP_IOAPIC_POLARITY_IGNORED: > > case KVM_CAP_TSC_DEADLINE_TIMER: > > case KVM_CAP_DISABLE_QUIRKS: > > @@ -4815,6 +4814,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) > > case KVM_CAP_VM_TYPES: > > r = kvm_caps.supported_vm_types; > > break; > > + case KVM_CAP_READONLY_MEM: > > + r = kvm ? kvm_arch_has_readonly_mem(kvm) : 1; > > Need a break here otherwise -Wimplicit-fallthrough option will warn. Heh, Nathan beat you to it: https://lore.kernel.org/all/20240905-kvm-x86-avoid-clang-implicit-fallthrough-v1-1-f2e785f1aa45@kernel.org