From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9CC2F3D5679 for ; Fri, 9 Oct 2026 20:50:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791579051; cv=none; b=jbtRZ/zJab3cuk5Yl35jsZDVRoRqPFy9y/MtiEdC+eXYDkIDHKddwvQUEQZjHgIhv/PB3UQgPAow83t0Hl4OX14pRjimTnl44+GfdI0O2lRy85ogytzfkdF/96KVsYwj7Ty5fO8xaCFaCt87jdSCmggSse5x1gbbSUAfcvXbQOM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791579051; c=relaxed/simple; bh=gcpgAAlstUAea7MeoephBSM8C3AiipGF3t9WWqRAKes=; h=From:To:Cc:Subject:Date:Message-ID:Content-Type:MIME-Version; b=rIrQxgsDUvzwNORagiKxE3X7TljUT8fi+iokHjoEorIDyjFCd+7QoSCBc6sCmgxX3EoFV9cKtRkd+tTRwDWk6Eb8LVaqdq8TuYTV9LusutdZaNs+kmk3GTlUW7+jfgqIvzSFs569a7q/bkD4Ebz+Dc93r2g9C8o/HPi8us2SfhM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=hErH9ccF; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hErH9ccF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1791579049; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=h6V5Kq3HUV5oYb9OPFBcxaJZjH3kjttdL3dZebuSKks=; b=hErH9ccFyQWMYw6mH56OcgmhAj19768EKsbJwZRJrCRgR4p3NZCTU4lwVXDZv8qHaThmYS EA2wnabSE3/y5iGquOSwu/CAReiTqx6GmqJuTdtfb2fTvBWWSTwIDoGRk36wC3KjexJEZr uf12fvGfQYbSgm+SZhj8c4cGnyvBB+M= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-553-dbbTl_wsOcu36Honji-mOw-1; Fri, 9 Oct 2026 20:50:39 +0000 X-MC-Unique: dbbTl_wsOcu36Honji-mOw-1 X-Mimecast-MFC-AGG-ID: dbbTl_wsOcu36Honji-mOw_1791579038 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B15CE1843AD4; Fri, 9 Oct 2026 20:50:38 +0000 (UTC) Received: from mlevitsk-thinkpadt14gen3.ibmmarkh.csb (headnet05.pony-001.prod.iad2.dc.redhat.com [10.2.32.117]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 99B6118004D4; Fri, 9 Oct 2026 20:50:37 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: x86@kernel.org, Sean Christopherson , Paolo Bonzini , linux-kernel@vger.kernel.org, Maxim Levitsky Subject: [PATCH 0/2] KVM: nVMX: fix nested APICv emulation for windows guests Date: Fri, 9 Oct 2026 16:50:34 -0400 Message-ID: <20261009205036.672523-1-mlevitsk@redhat.com> Content-Type: text/plain; charset="utf-8" Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Fix two problems that were recently discovered that cause nested APICv=0D to malfunction on windows with hyperv enabled.=0D =0D The first problem is that unlike KVM, windows doesn't set PIR.ON when=0D sending posted interrupts. X86 spec actually allows this.=0D =0D The second problem is that unlilke KVM, which mostly ignores them,=0D windows depends on accurate delivery of the posted notification=0D interrupts, even when those miss the guest.=0D =0D Best regards,=0D Maxim Levitsky=0D =0D Maxim Levitsky (2):=0D KVM: nVMX: don't check PIR.ON when processing nested posted interrupts=0D KVM: nVMX: avoid losing the posted notification interrupt when exiting=0D L2=0D =0D arch/x86/kvm/vmx/nested.c | 20 +++++++++++++++-----=0D 1 file changed, 15 insertions(+), 5 deletions(-)=0D =0D -- =0D 2.54.0=0D =0D