From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 20325314D03 for ; Mon, 10 Nov 2025 15:39:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762789178; cv=none; b=JIxQ7IUls6r5uu8pgbYJIfyZwLHzX4KKyE/3svZY2Tn4BLUZPRPdLp2lm7SAYCJiKXlEu/mAEBp9v3jzKd1G9zMaJToGARTRKcPEldVz7zxwrhNkt1p2rk2Gc3lelQGPvJ/LcIB6VvYu+j8yTmFJLf3GrZO/hlpg0i6DhJaZSgo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762789178; c=relaxed/simple; bh=HLqpw9OccrvyzVMI8pr94sqlLBqJLI8wM/NU8/1R4X4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=KYIPTXmZODYVf5XAmHyt0AI2BjhEpT2WL515/IA8Mtvxneu00ZlDki/p5jCrRg4tc1M5FSAq46icXatzHEtnzVb4e9mIIYI8TbnLrNYhr4WZ0UMOlNdCXbaLM0bcxgL3SxIUQJC9wEcFxHOEJxnLiEkmEB4WGvJ3fAcgTzC350Q= 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=J80sQnt5; arc=none smtp.client-ip=209.85.215.202 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="J80sQnt5" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-b8f8e1f1044so5120211a12.0 for ; Mon, 10 Nov 2025 07:39:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1762789174; x=1763393974; 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=IxV2BK8QKnCiH1AuK2g4amllIFkIURPoopgCW0Ha0PY=; b=J80sQnt5gziIRbw9fSifeRn8BYIsf1jg4gw6ZdmS9RIw5840ZKkrW7sfEfxeCiIoPO 8OGDzuc3vvVtLbGrcMvxkIcqwwa1TBPyn4S9bGzjrLRnP5r62KK29Vb/pFLGRbtT8gj9 C7C5X4cANXIPEeIOd0HmXl9JULUpX67Ncnfq3jXAJPOgS0wVi1wrDbTXHSbhuFZPzvuX fSB1TZDH9+v232CESYGHDs9KntKyzQV/pwkuUJ0H34CXCaPMFFneDtl6cA1rE0INC7xe N31upxXcVF00QY7vKF1xMz2Loijcxowhnt52P+Rr9Na9lU2wTBXPfoFo0XmD8vAjNEks rzGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762789174; x=1763393974; 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=IxV2BK8QKnCiH1AuK2g4amllIFkIURPoopgCW0Ha0PY=; b=fnb8s5zyX1PF/LlSFJWF/WAXDbAYG4R05WhZGQz/Ez3AT85eff6ul1LFc+tMZZr408 I63B+y7NMFXF15Kke9INdEBWFREN0JUGf0o4IzpnkUPplvFkwfweQco9GbcBbBsSqNf3 fIyrwFHR7u7chUlS9ErY5+prmb/pPPZ6x7voXhCQiak6NvenrOQFhq0BJUiWvk7aqMxP A7O7yqE9oJEUQt4XkZzMUJyxiG9C7vnYU3VS09nY+jsmtVonKEWRLeIPqe7UTxntPuFc 3l8bdqsbzrUqs+M0sv1m5PhmqfLjMZF9iQWN1M32kEm53WCSeafTvz4/gEjxiai8ICMY nQ2g== X-Forwarded-Encrypted: i=1; AJvYcCUlTqzo+WOViIURWWN/7PMuhRT+4oN7j9XUnyc4KTuG44Uhfme+YrlP6P0YODX2wPWWGCIyy2JodvaGbao=@vger.kernel.org X-Gm-Message-State: AOJu0Ywuptz73x51qjQHzxbaW3RURTDc2MkXlnoZxCIBByNXh/kfSkcM ND2c8OrCQ8yzbUVqFwP6zog87/n9K+9WJCLl54/Y+JMmfgSdh+USGw4LBtJBvn4YdABLAZJ2s4D QNKMqmw== X-Google-Smtp-Source: AGHT+IG1WjnuFZxaKrB2Uz9FQb9ICjT0M8KZd2b+Eh4t1Ia5GLPxzkUDRvJD7JP0d2vdeKv3tjb+ORIQYT0= X-Received: from pjbsv16.prod.google.com ([2002:a17:90b:5390:b0:33d:98cb:883b]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3cc3:b0:33f:eca0:47ae with SMTP id 98e67ed59e1d1-3436cbc9a33mr8936483a91.28.1762789173839; Mon, 10 Nov 2025 07:39:33 -0800 (PST) Date: Mon, 10 Nov 2025 07:37:25 -0800 In-Reply-To: <20251106191230.182393-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251106191230.182393-1-seanjc@google.com> X-Mailer: git-send-email 2.51.2.1041.gc1ab5b90ca-goog Message-ID: <176254226343.805329.8193068148325939353.b4-ty@google.com> Subject: Re: [PATCH v2] KVM: SVM: Ensure SPEC_CTRL[63:32] is context switched between guest and host From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Uros Bizjak Content-Type: text/plain; charset="utf-8" On Thu, 06 Nov 2025 11:12:30 -0800, Sean Christopherson wrote: > SPEC_CTRL is an MSR, i.e. a 64-bit value, but the VMRUN assembly code > assumes bits 63:32 are always zero. The bug is _currently_ benign because > neither KVM nor the kernel support setting any of bits 63:32, but it's > still a bug that needs to be fixed. Applied to kvm-x86 svm, with the comment fixups. [1/1] KVM: SVM: Ensure SPEC_CTRL[63:32] is context switched between guest and host https://github.com/kvm-x86/linux/commit/c331b400e291 -- https://github.com/kvm-x86/linux/tree/next