From patchwork Fri Feb 7 03:09:00 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yan Zhao X-Patchwork-Id: 13964279 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) (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 F10381624C5; Fri, 7 Feb 2025 03:10:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.19 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738897814; cv=none; b=Am5Ek7BIJNSy9LSy8SEjvovyNd60gW9r8S97vpk6WPvRjDFxl30uGHZ0RL/+/6bKSisHZCTtv2IZGHPozTelug5aIomrzw2qEbW6F4cltJp7VAePmAOLzO0KP5xwYuyazF3UEGtG6YgM4fG150PXv3nzjVCiCRHqT7amEEPlo14= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738897814; c=relaxed/simple; bh=HEjW7p9mYif0anOP9XOUbSqHykMLvVgQ2FWDqLTVVDU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cZ9qAbOLM7a/mzA9uLfn9zRDQlh7ne96ga7EiaH/E7EncfhFrYkCeAnPmIT7TCrn9Fg9KTjH9l02+ixBpYcVaanwv4xaiBPqnTyaazZWZbl4q4S71UBd+4Ke1BU8U/Oh92mKjajVTprhQESHwMvU0hoWO03zKplVW7TXRPfDgiU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=Ho0Mvoof; arc=none smtp.client-ip=192.198.163.19 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="Ho0Mvoof" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1738897813; x=1770433813; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=HEjW7p9mYif0anOP9XOUbSqHykMLvVgQ2FWDqLTVVDU=; b=Ho0MvoofxEWygBbtfhBxvsSc2d7qtw8qJwesItMgmoJ+MuD+al62VeDa PFdEg/TyWceJnxFhAW79w0FzVTApmxXv3H176yVwp3wbxctdE3DfIYn9R JDkyFoBPw0vIRWlUJG+4915GJ2R/NIca/wFg8wZ+LLMwW+iJYYv2qRdXg XYdrpsp0SFAAWza45kUudbsPZlzND4+3c43N5rxf2rO36+FZkxrbTrH3R DEV+TSRjblYDB2Fg1D1R71N/V6YPCmNCJTrs7Wa3PDc/VE4Tqg31TIM1/ MK28b4u391/hPH7ZICzYJY182tGlRrIBFdP8LSQr2M8JpsPQuXaAqILdu Q==; X-CSE-ConnectionGUID: d11pezsvQgmEgjpPaOo67g== X-CSE-MsgGUID: oB3Of98kT0C8U/SxtOiUxg== X-IronPort-AV: E=McAfee;i="6700,10204,11336"; a="38731403" X-IronPort-AV: E=Sophos;i="6.13,266,1732608000"; d="scan'208";a="38731403" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Feb 2025 19:10:12 -0800 X-CSE-ConnectionGUID: DxVbil/NQYGzhRcuQ80jXA== X-CSE-MsgGUID: Uy2YKcudSs65ART/GtG7IQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.13,266,1732608000"; d="scan'208";a="116412063" Received: from yzhao56-desk.sh.intel.com ([10.239.159.62]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Feb 2025 19:10:08 -0800 From: Yan Zhao To: pbonzini@redhat.com, seanjc@google.com Cc: rick.p.edgecombe@intel.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Yan Zhao Subject: [PATCH 3/4] KVM: x86/mmu: Make sure pfn is not changed for spurious fault Date: Fri, 7 Feb 2025 11:09:00 +0800 Message-ID: <20250207030900.1808-1-yan.y.zhao@intel.com> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20250207030640.1585-1-yan.y.zhao@intel.com> References: <20250207030640.1585-1-yan.y.zhao@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Make sure pfn is not changed for a spurious fault by warning in the TDP MMU. For shadow path, only treat a prefetch fault as spurious when pfn is not changed, since the rmap removal and add are required when pfn is changed. Cc: Sean Christopherson Signed-off-by: Yan Zhao --- arch/x86/kvm/mmu/mmu.c | 3 ++- arch/x86/kvm/mmu/tdp_mmu.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 3d74e680006f..47fd3712afe6 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -2846,7 +2846,8 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, } if (is_shadow_present_pte(*sptep)) { - if (prefetch && is_last_spte(*sptep, level)) + if (prefetch && is_last_spte(*sptep, level) && + pfn == spte_to_pfn(*sptep)) return RET_PF_SPURIOUS; /* diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 5f9e7374220e..8b37e4f542f3 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1139,7 +1139,8 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, if (is_shadow_present_pte(iter->old_spte) && is_access_allowed(fault, iter->old_spte) && - is_last_spte(iter->old_spte, iter->level)) + is_last_spte(iter->old_spte, iter->level) && + !WARN_ON_ONCE(fault->pfn != spte_to_pfn(iter->old_spte))) return RET_PF_SPURIOUS; if (unlikely(!fault->slot))