From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (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 906B04DC53F for ; Mon, 2 Mar 2026 20:41:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772484107; cv=none; b=nhzvUNnL/jP58hfuPrJDC7eQiWnVOu3EBDT0jPogZU31fIAxXYi5dG/WnpGklqV10dtbMh4XAyFxnEM56xhxhU9zKiaQ5jvZofSDx0zLt0II7EMYfNbu5h5t5DnaRJYgcO3kKr53LOPLfkJ0VEDOi0/nDyioFYTcNU4iFHiNoR8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772484107; c=relaxed/simple; bh=R/MIcxqUVQTwE5wwGHyGtW9Y/bGlblc1zMp+2swWJbA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=nNLAUj/eToPMQtJr2yGhJ5GCilhqMRc5kjtxD4B6nU3kpZtmiBn7U0Xhzl0Tq5qYrm55AiLFJWL4rHS4EwUIuInhBZVjiNLrXYfJTkVvoiFzTGmgMpap2DMC4tBu0IMjRmKhFt96cXNVaaNVG5hOixYJ1l2pnAxYMpvzTaHVavM= 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=RLTXvBuI; arc=none smtp.client-ip=209.85.216.74 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="RLTXvBuI" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-3598d3e3bc7so1268086a91.3 for ; Mon, 02 Mar 2026 12:41:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1772484106; x=1773088906; 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=LgZDmqmpagJozBHMzfcbK0Tu/J0kjNTVJeXoQ0mkXOo=; b=RLTXvBuIv+tpS/Y4nq4dGMGUemVDivwhhxcYUlswcPt7lFpV1LDYYeCDiH8SDr+eSE A7yPRj5NMUJYu0L1Dw8nOnlecvKDeh2XVosoiBXFX4i4LmPteiyV+nwigY8Pos5Qg+xa /wLjHqB2SIbcTZV9IbkOEy8brhzKgqJpMqD3BrzydBIb5fMREdE1tVSaT40xtYfIs3JS 9kI+3YXL/JwYOM6nqL+OWQVUVtHmjlfJObefcFp0VwxtfvYU9OIndFgAyZIf380a9Wmh 652egbnj1UvdeMZnt0dwhmCK9kemdK+EwkUufdmU6vAfw6AdrdeTu6keJjMXg6itRGEh AjEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772484106; x=1773088906; 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=LgZDmqmpagJozBHMzfcbK0Tu/J0kjNTVJeXoQ0mkXOo=; b=YxilhJbF+rn+QjXBOZbRZ5+54WOWg7f0SBxRBYwkzGIVoZMn9TnGHs0rwvHE8ZAU+T on6yyMaZKAlMKWG2zAyA/6uS0Mj8VxuedBUsUfB0AHMwzBWCSSS53R1LZEOEDw95jPWI hsAcAlxpJrVtwAKGCpAClORUDNRkYTBCLtPKJuYDYBFN1bRbq/b9he04v9Kx3IkLMgbi v/7LZLyGnmFXWXVGzg5AA2dweZthLyXVn22qMK0+hTIu5nOBAb9KPQgVWqjuToBM/TM1 gLDufJDFy2FpZi3j0Bfb8vGMznvc2pVC8Wfg8YBnC9OspnraeAvUOnFVIXxGmvteOSdI iZ+Q== X-Forwarded-Encrypted: i=1; AJvYcCWyBw+Db3mcRDpBtD9n+V9uXRVQdL/ayrRT00Sd1bdHWhVUS92bpvcR+bBWmKzZduL44i4=@vger.kernel.org X-Gm-Message-State: AOJu0YxxaDpx9zetj2vs6D6q+EEYU7e7j3/R7NIoBDrBs0qtUPPNB/5l oTgRPo9H6vgADwxLxBEQX24aoUdLon0QT7ZmwG1t011v1GaUdsO3EmvvuYzFwB5mn/5WeAWaRKQ YRZ4eBw== X-Received: from pjwo3.prod.google.com ([2002:a17:90a:d243:b0:359:8c13:8588]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:524a:b0:356:7b41:d348 with SMTP id 98e67ed59e1d1-35965cd00e3mr10408302a91.20.1772484105712; Mon, 02 Mar 2026 12:41:45 -0800 (PST) Date: Mon, 2 Mar 2026 12:41:44 -0800 In-Reply-To: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260225005950.3739782-1-yosry@kernel.org> <20260225005950.3739782-3-yosry@kernel.org> Message-ID: Subject: Re: [PATCH v3 2/8] KVM: nSVM: Sync interrupt shadow to cached vmcb12 after VMRUN of L2 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="us-ascii" On Fri, Feb 27, 2026, Yosry Ahmed wrote: > > diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c > > index de90b104a0dd5..9909ff237e5ca 100644 > > --- a/arch/x86/kvm/svm/nested.c > > +++ b/arch/x86/kvm/svm/nested.c > > @@ -521,6 +521,7 @@ void nested_sync_control_from_vmcb02(struct vcpu_svm *svm) > > u32 mask; > > svm->nested.ctl.event_inj = svm->vmcb->control.event_inj; > > svm->nested.ctl.event_inj_err = svm->vmcb->control.event_inj_err; > > + svm->nested.ctl.int_state = svm->vmcb->control.int_state; > > FWIW, this is an incomplete fix. KVM might update the interrupt shadow > after this point through __svm_skip_emulated_instruction(), and that > won't be captured in svm->nested.ctl.int_state. > > I think it's not worth fixing that case too, and any further effort > should go toward teaching KVM_GET_NESTED_STATE to pull state from the > correct place as discussed earlier. +1. FWIW, AMD doesn't have a MOV/POP SS shadow, so practically speaking the only impact is that an STI shadow could get extended for one extra instruction. Unless the guest is doing e.g. "sti; hlt; cli", that's a non-issue.