From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) (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 4B50835C6B4 for ; Wed, 22 Jul 2026 20:46:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.198 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784753161; cv=none; b=aPIpR1iA50HZzIlhKWlvSS23X4FmqWC0ZlW+q3YqprkpO0Txf2NSD48rNRRVji/UMgnJYXRYscYv0xGL2JXHjolLM1nm3m/CTiWqb9kGQkEHyHSq+xgpLkyeDIkS+6/lP2naYGwM7nBTqxMDdQBc4d4oCzBOThUiTuieLes1I3w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784753161; c=relaxed/simple; bh=Jro+S1urwV9VgFmKgbhzrATwwOWCyi2FY/Wr2eFCpEY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=tkR9aI5MlYtw7fZAWaqljwQdDhZD6Zg3FT6xjOjgBgT26q5M6/htmrPwT6mzflsT35HOKnt4mF3JjFTZY58Qh5rJEddWNx5FWJI1igLy25HzHOfCtWkJIWkK5YCBauvdwxi1kZ9zympoimXm8dzWjxxIvrMgZeY9DBhBe4ng9XI= 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=HcT3AwZJ; arc=none smtp.client-ip=209.85.210.198 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="HcT3AwZJ" Received: by mail-pf1-f198.google.com with SMTP id d2e1a72fcca58-8486ffba174so21107101b3a.1 for ; Wed, 22 Jul 2026 13:46:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1784753159; x=1785357959; darn=vger.kernel.org; h=content-transfer-encoding:content-type:cc:to:from:subject :message-id:references:mime-version:in-reply-to:date:from:to:cc :subject:date:message-id:reply-to:content-type; bh=SisaSmmFXYUYWjETBTWlOGLFpT6OcQLzXOoQK4qPlWM=; b=HcT3AwZJT9agiKrrLhKXzz93q0PYM6sSlChhP7vgm8/M9P+8lL8EkHd8bB6S1uA/eo b6KCh4Mw2Tx4ca1YqTtBvvg2WmA62omMZ/bcyr0qARp99Btv+/dcJlf7hj8grI056WeH RMnMWu4NzfPfygvUkhCc/Ooa8K9+mHdAPNrcsPhLM+iPEfbf495aJgINrJ6DsPEUAco6 Ew7Mw7+n5A7+SAPLopLdZoc/3gB+cb3J2I9af3Lh0s7UKl5rwAoFFRRX2NpXXY2C2ScO bt7aH4ZdL/BKMUw+iPuP0/l0/wERTyjKgUnuBEtLUWu21g6bywxdUN4Gf820Jf7SXCWp KRTw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784753159; x=1785357959; h=content-transfer-encoding:content-type: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 :content-type; bh=SisaSmmFXYUYWjETBTWlOGLFpT6OcQLzXOoQK4qPlWM=; b=CHu4NZ/MBHqt/1UvXhQ05BPJS6aqRmehBzYaagOptuCdWJ/Mgn+gPqUXFp0vr0t7P+ AZgmVOlHPizVH8/pxfc7PR386CeO1g8wHaAuK2FHYLxV4UlM0FK4EX1j7HG9gi7zdyjV 9uak9bcYllrEUM7EEghX1hapj04gAgwo56e/ZnxgisXq8/Ug8Jz3TCRDAlKn6kw6Phgn Qc9p21O5+8Kug55pSqJNLGLeFlwxONXhRuou1nzAxeOxKJ0WYuR2fGTWuVH78+nHL/c5 UZSsJjqf7NXhap7F9sycW8fI8As93x0BYLbsoilv8jM68qE/kriCTz3rwUDy/VZGx0Ol 3bPA== X-Forwarded-Encrypted: i=1; AHgh+RpJHU0lgAhJm9uWnNT4lY66MFpbh9Ht1MDxQ56D8e3CAMoyPeEoZupO0peRa0idqoI21ATMa6cGs7kTVio=@vger.kernel.org X-Gm-Message-State: AOJu0Yx82eFE+Vaa4rlwGSgNEWMNCKn0GUTgPm2ZF5pwlr72qZMbtTCP vh4qwMngvnxFQOI1cviigrArstQuS9/icWL9smt+0kATXck6D8pgEpP1uBpossnfKeGBuAQB4Lg jVI18Bw== X-Received: from pfbfc30.prod.google.com ([2002:a05:6a00:2e1e:b0:845:f28c:430e]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:21c9:b0:848:60d5:9526 with SMTP id d2e1a72fcca58-84e2bb37304mr483794b3a.43.1784753159239; Wed, 22 Jul 2026 13:45:59 -0700 (PDT) Date: Wed, 22 Jul 2026 13:45:58 -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: <20260713180153.2728382-1-yosry@kernel.org> <20260713180153.2728382-2-yosry@kernel.org> Message-ID: Subject: Re: [PATCH v3 1/2] KVM: x86: Check EFER validity on KVM_SET_SREGS* From: Sean Christopherson To: Yosry Ahmed Cc: Paolo Bonzini , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Mon, Jul 13, 2026, Yosry Ahmed wrote: > On Mon, Jul 13, 2026 at 11:02=E2=80=AFAM Yosry Ahmed w= rote: > > > > When handling userspace SREGS writes, check the validity of EFER (i.e. > > allowed bits) before writing the new value of EFER through the > > per-vendor set_efer callbacks. This prevents userspace from writing > > bogus values (e.g. EFER.SVME=3D1 with nested=3D0). > > > > Note: on KVM_SET_MSRS, KVM only checks EFER validity in terms of KVM > > caps, not guest caps, so it is possible to set EFER bits that are > > supported by KVM but not by the guest CPUID. Potentially allowing > > userspace to set msrs before CPUID. > > > > However, for KVM_SET_SREGS*, check the validity of the set bits against > > both KVM and guest caps. This is consistent with other validity checks > > (e.g. for CR4) that check validity against guest caps, which already > > imposes the need to set CPUID before SREGS. > > > > Cc: stable@vger.kernel.org > > Change-Id: I45701ec440e4fdd8f086eb70db0c0845fb0ed509 >=20 > Forgot to drop these, sorry :/ By "these", I assume you mean the Change-Id here and in the next patch? Bu= t keep the Cc: stable@?