From patchwork Mon Apr 7 07:49:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chenyi Qiang X-Patchwork-Id: 14039925 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (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 D880F226883 for ; Mon, 7 Apr 2025 07:50:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.9 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744012231; cv=none; b=T7855+Y+adpfZvy/hxxDNy9A7IlocyeExy3uMYqv7rOfyZnzr15lGFfS4Y6oPev8H4beHPiW+Bgu1/LM2FsNZ55mfJX5HN4RNw4P/MzEQzF4eI9MwRrbboLhSZ3nIPyW7ZBO1jqkuDiyrTGKvSdLb/YinxlckHXf7u42IrieLt0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744012231; c=relaxed/simple; bh=LMM4jg2KgMvxa59xhZRJFI8Q6LECqUZX8PbGNMlnhmI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rKlIYJPN8m9Fw0PukkNpm02UlkXWYqb5cXHZlveOCH1uu9D+2Qhc7SgZW5af1Ea6BatHhW/qmGsBO6pjcaWMW3LfOTZ0hHte3CBijbugsm36vsVbhZG3eDdJB+8lvbW2QyjPvfw9SZntP4HBbWmJooGf747w04p8t2sWPbARSNM= 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=SLDvahDD; arc=none smtp.client-ip=198.175.65.9 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="SLDvahDD" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1744012230; x=1775548230; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LMM4jg2KgMvxa59xhZRJFI8Q6LECqUZX8PbGNMlnhmI=; b=SLDvahDDypKvu9QpZi+IHwuPN1py72J2jzDm2a4jHEEC34jOaYAjKiTZ k8RtJKAK6n4cBE8+154AlxiwpRtAv9ugCdbeEdoR4u7pTg2nNw+00mFIm R6N60HaOcO+9nL89HFkWRVBB4rwfjF15n5G0UA1o1lLP4rxx++QL21sRf FNCUZW+rl+xhNSHt0cDktrOFeG3ulWPFtsjb1yGwyVnWNcTb3qTnEfvSe uPCENs8GqBnSmWCCoeWgBOo2rALOB6othpq9EgnhKqmPAF//yx1TSL9Ez lm7qunAwBraLl7g6h2hHdQ3+v6y6rsH/9q6RELZya3NZpBB+q1937bdPY g==; X-CSE-ConnectionGUID: kvDkuGAeSRuYWucV9xGkhQ== X-CSE-MsgGUID: i5i+kCkyReWVMpiaUwc3HA== X-IronPort-AV: E=McAfee;i="6700,10204,11396"; a="67857596" X-IronPort-AV: E=Sophos;i="6.15,193,1739865600"; d="scan'208";a="67857596" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Apr 2025 00:50:30 -0700 X-CSE-ConnectionGUID: kzUdn2HcR1SCId2TI2iwPg== X-CSE-MsgGUID: DHbBCsbTSEi+NmWP/DDS1w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.15,193,1739865600"; d="scan'208";a="128405694" Received: from emr-bkc.sh.intel.com ([10.112.230.82]) by orviesa007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Apr 2025 00:50:25 -0700 From: Chenyi Qiang To: David Hildenbrand , Alexey Kardashevskiy , Peter Xu , Gupta Pankaj , Paolo Bonzini , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Michael Roth Cc: Chenyi Qiang , qemu-devel@nongnu.org, kvm@vger.kernel.org, Williams Dan J , Peng Chao P , Gao Chao , Xu Yilun , Li Xiaoyao Subject: [PATCH v4 11/13] KVM: Introduce CVMPrivateSharedListener for attribute changes during page conversions Date: Mon, 7 Apr 2025 15:49:31 +0800 Message-ID: <20250407074939.18657-12-chenyi.qiang@intel.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250407074939.18657-1-chenyi.qiang@intel.com> References: <20250407074939.18657-1-chenyi.qiang@intel.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 With the introduction of the RamBlockAttribute object to manage RAMBlocks with guest_memfd and the implementation of PrivateSharedManager interface to convey page conversion events, it is more elegant to move attribute changes into a PrivateSharedListener. The PrivateSharedListener is reigstered/unregistered for each memory region section during kvm_region_add/del(), and listeners are stored in a CVMPrivateSharedListener list for easy management. The listener handler performs attribute changes upon receiving notifications from private_shared_manager_state_change() calls. With this change, the state changes operations in kvm_convert_memory() can be removed. Note that after moving attribute changes into a listener, errors can be returned in ram_block_attribute_notify_to_private() if attribute changes fail in corner cases (e.g. -ENOMEM). Since there is currently no rollback operation for the to_private case, an assert is used to prevent the guest from continuing with a partially changed attribute state. Signed-off-by: Chenyi Qiang --- Changes in v4: - Newly added. --- accel/kvm/kvm-all.c | 73 ++++++++++++++++++--- include/system/confidential-guest-support.h | 10 +++ system/ram-block-attribute.c | 17 ++++- target/i386/kvm/tdx.c | 1 + target/i386/sev.c | 1 + 5 files changed, 90 insertions(+), 12 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 546b58b737..aec64d559b 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -48,6 +48,7 @@ #include "kvm-cpus.h" #include "system/dirtylimit.h" #include "qemu/range.h" +#include "system/confidential-guest-support.h" #include "hw/boards.h" #include "system/stats.h" @@ -1691,28 +1692,91 @@ static int kvm_dirty_ring_init(KVMState *s) return 0; } +static int kvm_private_shared_notify(StateChangeListener *scl, + MemoryRegionSection *section, + bool to_private) +{ + hwaddr start = section->offset_within_address_space; + hwaddr size = section->size; + + if (to_private) { + return kvm_set_memory_attributes_private(start, size); + } else { + return kvm_set_memory_attributes_shared(start, size); + } +} + +static int kvm_private_shared_notify_to_shared(StateChangeListener *scl, + MemoryRegionSection *section) +{ + return kvm_private_shared_notify(scl, section, false); +} + +static int kvm_private_shared_notify_to_private(StateChangeListener *scl, + MemoryRegionSection *section) +{ + return kvm_private_shared_notify(scl, section, true); +} + static void kvm_region_add(MemoryListener *listener, MemoryRegionSection *section) { KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener); + ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; + GenericStateManager *gsm = memory_region_get_generic_state_manager(section->mr); KVMMemoryUpdate *update; + CVMPrivateSharedListener *cpsl; + PrivateSharedListener *psl; + update = g_new0(KVMMemoryUpdate, 1); update->section = *section; QSIMPLEQ_INSERT_TAIL(&kml->transaction_add, update, next); + + if (!memory_region_has_guest_memfd(section->mr) || !gsm) { + return; + } + + cpsl = g_new0(CVMPrivateSharedListener, 1); + cpsl->mr = section->mr; + cpsl->offset_within_address_space = section->offset_within_address_space; + cpsl->granularity = generic_state_manager_get_min_granularity(gsm, section->mr); + psl = &cpsl->listener; + QLIST_INSERT_HEAD(&cgs->cvm_private_shared_list, cpsl, next); + private_shared_listener_init(psl, kvm_private_shared_notify_to_shared, + kvm_private_shared_notify_to_private); + generic_state_manager_register_listener(gsm, &psl->scl, section); } static void kvm_region_del(MemoryListener *listener, MemoryRegionSection *section) { KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener); + ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; + GenericStateManager *gsm = memory_region_get_generic_state_manager(section->mr); KVMMemoryUpdate *update; + CVMPrivateSharedListener *cpsl; + PrivateSharedListener *psl; update = g_new0(KVMMemoryUpdate, 1); update->section = *section; QSIMPLEQ_INSERT_TAIL(&kml->transaction_del, update, next); + if (!memory_region_has_guest_memfd(section->mr) || !gsm) { + return; + } + + QLIST_FOREACH(cpsl, &cgs->cvm_private_shared_list, next) { + if (cpsl->mr == section->mr && + cpsl->offset_within_address_space == section->offset_within_address_space) { + psl = &cpsl->listener; + generic_state_manager_unregister_listener(gsm, &psl->scl); + QLIST_REMOVE(cpsl, next); + g_free(cpsl); + break; + } + } } static void kvm_region_commit(MemoryListener *listener) @@ -3076,15 +3140,6 @@ int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private) goto out_unref; } - if (to_private) { - ret = kvm_set_memory_attributes_private(start, size); - } else { - ret = kvm_set_memory_attributes_shared(start, size); - } - if (ret) { - goto out_unref; - } - addr = memory_region_get_ram_ptr(mr) + section.offset_within_region; rb = qemu_ram_block_from_host(addr, false, &offset); diff --git a/include/system/confidential-guest-support.h b/include/system/confidential-guest-support.h index b68c4bebbc..64f67db19a 100644 --- a/include/system/confidential-guest-support.h +++ b/include/system/confidential-guest-support.h @@ -23,12 +23,20 @@ #endif #include "qom/object.h" +#include "exec/memory.h" #define TYPE_CONFIDENTIAL_GUEST_SUPPORT "confidential-guest-support" OBJECT_DECLARE_TYPE(ConfidentialGuestSupport, ConfidentialGuestSupportClass, CONFIDENTIAL_GUEST_SUPPORT) +typedef struct CVMPrivateSharedListener { + MemoryRegion *mr; + hwaddr offset_within_address_space; + uint64_t granularity; + PrivateSharedListener listener; + QLIST_ENTRY(CVMPrivateSharedListener) next; +} CVMPrivateSharedListener; struct ConfidentialGuestSupport { Object parent; @@ -38,6 +46,8 @@ struct ConfidentialGuestSupport { */ bool require_guest_memfd; + QLIST_HEAD(, CVMPrivateSharedListener) cvm_private_shared_list; + /* * ready: flag set by CGS initialization code once it's ready to * start executing instructions in a potentially-secure diff --git a/system/ram-block-attribute.c b/system/ram-block-attribute.c index 06ed134cda..15c9aebd09 100644 --- a/system/ram-block-attribute.c +++ b/system/ram-block-attribute.c @@ -259,6 +259,7 @@ static void ram_block_attribute_notify_to_private(RamBlockAttribute *attr, uint64_t offset, uint64_t size) { PrivateSharedListener *psl; + int ret; QLIST_FOREACH(psl, &attr->psl_list, next) { StateChangeListener *scl = &psl->scl; @@ -267,7 +268,12 @@ static void ram_block_attribute_notify_to_private(RamBlockAttribute *attr, if (!memory_region_section_intersect_range(&tmp, offset, size)) { continue; } - scl->notify_to_state_clear(scl, &tmp); + /* + * No undo operation for the state_clear() callback failure at present. + * Expect the state_clear() callback always succeed. + */ + ret = scl->notify_to_state_clear(scl, &tmp); + g_assert(!ret); } } @@ -275,7 +281,7 @@ static int ram_block_attribute_notify_to_shared(RamBlockAttribute *attr, uint64_t offset, uint64_t size) { PrivateSharedListener *psl, *psl2; - int ret = 0; + int ret = 0, ret2 = 0; QLIST_FOREACH(psl, &attr->psl_list, next) { StateChangeListener *scl = &psl->scl; @@ -302,7 +308,12 @@ static int ram_block_attribute_notify_to_shared(RamBlockAttribute *attr, if (!memory_region_section_intersect_range(&tmp, offset, size)) { continue; } - scl2->notify_to_state_clear(scl2, &tmp); + /* + * No undo operation for the state_clear() callback failure at present. + * Expect the state_clear() callback always succeed. + */ + ret2 = scl2->notify_to_state_clear(scl2, &tmp); + g_assert(!ret2); } } return ret; diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c index c906a76c4c..718385c8de 100644 --- a/target/i386/kvm/tdx.c +++ b/target/i386/kvm/tdx.c @@ -1179,6 +1179,7 @@ static void tdx_guest_init(Object *obj) qemu_mutex_init(&tdx->lock); cgs->require_guest_memfd = true; + QLIST_INIT(&cgs->cvm_private_shared_list); tdx->attributes = TDX_TD_ATTRIBUTES_SEPT_VE_DISABLE; object_property_add_uint64_ptr(obj, "attributes", &tdx->attributes, diff --git a/target/i386/sev.c b/target/i386/sev.c index 217b19ad7b..6647727a44 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -2432,6 +2432,7 @@ sev_snp_guest_instance_init(Object *obj) SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); cgs->require_guest_memfd = true; + QLIST_INIT(&cgs->cvm_private_shared_list); /* default init/start/finish params for kvm */ sev_snp_guest->kvm_start_conf.policy = DEFAULT_SEV_SNP_POLICY;