From patchwork Wed Jul 12 23:01:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Haitao Huang X-Patchwork-Id: 13310967 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35E61C04A6A for ; Wed, 12 Jul 2023 23:02:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232733AbjGLXCS (ORCPT ); Wed, 12 Jul 2023 19:02:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50486 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231987AbjGLXCL (ORCPT ); Wed, 12 Jul 2023 19:02:11 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED8EE11D; Wed, 12 Jul 2023 16:02:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1689202930; x=1720738930; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LP9W4hlkm5ekzqLCSSJ7Z7Ak8eW+S808RjkB/UQVNtg=; b=hLJvN1em6sEGSJtNcSpguutP/9RqhfcVp+SrgSJn83s5If6i3PnIHcjt NJ47J4gaLLmTvbYh+NwiV4beYftSCfQdGgi36HgfVxT3sBmywqFKmDcQt CHr9OAPfNkRukIh3mx/oh/Cr7smbP/GKN/J32AR5aV54aJpYcCimgfANs QRMSn20KBPVRlGVYx4Isf7MtHPjL1Vxulq20kvDR64Tqibj9dgnDkWORj K44uyAmkHXs+WWmJ93WojLjm3bK/kzSY5ijm2DUpiYmqtg+WD6RBj4iJi AFtQocVfsLTcUarBaQFfkrLjbRN8v6YW90y9S1uGZmoTV+KD7rOJOM3R3 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10769"; a="428773946" X-IronPort-AV: E=Sophos;i="6.01,200,1684825200"; d="scan'208";a="428773946" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jul 2023 16:02:08 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10769"; a="835338601" X-IronPort-AV: E=Sophos;i="6.01,200,1684825200"; d="scan'208";a="835338601" Received: from b4969161e530.jf.intel.com ([10.165.56.46]) by fmsmga002.fm.intel.com with ESMTP; 12 Jul 2023 16:02:06 -0700 From: Haitao Huang To: jarkko@kernel.org, dave.hansen@linux.intel.com, tj@kernel.org, linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org, cgroups@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" Cc: kai.huang@intel.com, reinette.chatre@intel.com, Kristen Carlson Accardi , zhiquan1.li@intel.com, seanjc@google.com Subject: [PATCH v3 06/28] x86/sgx: store unreclaimable EPC pages in sgx_epc_lru_lists Date: Wed, 12 Jul 2023 16:01:40 -0700 Message-Id: <20230712230202.47929-7-haitao.huang@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230712230202.47929-1-haitao.huang@linux.intel.com> References: <20230712230202.47929-1-haitao.huang@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org From: Kristen Carlson Accardi When an OOM event occurs, all pages associated with an enclave will need to be freed, including pages that are not currently tracked by the reclaimer. A previous patch converted the SGX code to use a pair of generic "sgx_record/drop_epc_pages()" for storing the EPC pages that are tracked by the reclaimer. This patch utilizes those functions to store the remaining untracked pages to a new "unreclaimable" list stored with the struct sgx_epc_lru_lists struct. Signed-off-by: Kristen Carlson Accardi Signed-off-by: Haitao Huang V3: - Removed tracking virtual EPC pages in unreclaimable list as host kernel does not reclaim them. The EPC cgroups implemented later only blocks allocating for a guest if the limit is reached by returning -ENOMEM from sgx_alloc_epc_page() called by virt_epc, and does nothing else. Therefore, no need to track those in LRU lists. --- arch/x86/kernel/cpu/sgx/encl.c | 8 ++++++-- arch/x86/kernel/cpu/sgx/ioctl.c | 4 +++- arch/x86/kernel/cpu/sgx/main.c | 3 +++ arch/x86/kernel/cpu/sgx/sgx.h | 5 +++++ 4 files changed, 17 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c index f68af9e37daa..edb8d8c1c229 100644 --- a/arch/x86/kernel/cpu/sgx/encl.c +++ b/arch/x86/kernel/cpu/sgx/encl.c @@ -252,7 +252,8 @@ static struct sgx_encl_page *__sgx_encl_load_page(struct sgx_encl *encl, epc_page = sgx_encl_eldu(&encl->secs, NULL); if (IS_ERR(epc_page)) return ERR_CAST(epc_page); - epc_page->flags |= SGX_EPC_OWNER_ENCL_PAGE; + sgx_record_epc_page(epc_page, SGX_EPC_OWNER_ENCL_PAGE | + SGX_EPC_PAGE_RECLAIMER_UNTRACKED); } epc_page = sgx_encl_eldu(entry, encl->secs.epc_page); @@ -724,6 +725,7 @@ void sgx_encl_release(struct kref *ref) xa_destroy(&encl->page_array); if (!encl->secs_child_cnt && encl->secs.epc_page) { + sgx_drop_epc_page(encl->secs.epc_page); sgx_encl_free_epc_page(encl->secs.epc_page); encl->secs.epc_page = NULL; } @@ -732,6 +734,7 @@ void sgx_encl_release(struct kref *ref) va_page = list_first_entry(&encl->va_pages, struct sgx_va_page, list); list_del(&va_page->list); + sgx_drop_epc_page(va_page->epc_page); sgx_encl_free_epc_page(va_page->epc_page); kfree(va_page); } @@ -1238,7 +1241,8 @@ struct sgx_epc_page *sgx_alloc_va_page(struct sgx_encl *encl, bool reclaim) sgx_encl_free_epc_page(epc_page); return ERR_PTR(-EFAULT); } - epc_page->flags |= SGX_EPC_OWNER_ENCL; + sgx_record_epc_page(epc_page, SGX_EPC_OWNER_ENCL | + SGX_EPC_PAGE_RECLAIMER_UNTRACKED); return epc_page; } diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c index dd7ab1c80db6..4e6d0c9d043a 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -48,6 +48,7 @@ void sgx_encl_shrink(struct sgx_encl *encl, struct sgx_va_page *va_page) encl->page_cnt--; if (va_page) { + sgx_drop_epc_page(va_page->epc_page); sgx_encl_free_epc_page(va_page->epc_page); list_del(&va_page->list); kfree(va_page); @@ -113,7 +114,8 @@ static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs) encl->attributes = secs->attributes; encl->attributes_mask = SGX_ATTR_UNPRIV_MASK; - encl->secs.epc_page->flags |= SGX_EPC_OWNER_ENCL_PAGE; + sgx_record_epc_page(encl->secs.epc_page, SGX_EPC_OWNER_ENCL_PAGE | + SGX_EPC_PAGE_RECLAIMER_UNTRACKED); /* Set only after completion, as encl->lock has not been taken. */ set_bit(SGX_ENCL_CREATED, &encl->flags); diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index 371135665ff7..9252728865fa 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -268,6 +268,7 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page, goto out; sgx_encl_ewb(encl->secs.epc_page, &secs_backing); + sgx_drop_epc_page(encl->secs.epc_page); sgx_encl_free_epc_page(encl->secs.epc_page); encl->secs.epc_page = NULL; @@ -511,6 +512,8 @@ void sgx_record_epc_page(struct sgx_epc_page *page, unsigned long flags) page->flags |= flags; if (flags & SGX_EPC_PAGE_RECLAIMER_TRACKED) list_add_tail(&page->list, &sgx_global_lru.reclaimable); + else + list_add_tail(&page->list, &sgx_global_lru.unreclaimable); spin_unlock(&sgx_global_lru.lock); } diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h index c60bbd995942..9f780b2c4cfe 100644 --- a/arch/x86/kernel/cpu/sgx/sgx.h +++ b/arch/x86/kernel/cpu/sgx/sgx.h @@ -23,6 +23,9 @@ #define SGX_NR_LOW_PAGES 32 #define SGX_NR_HIGH_PAGES 64 +/* Pages, which are not tracked by the page reclaimer. */ +#define SGX_EPC_PAGE_RECLAIMER_UNTRACKED 0 + /* Pages, which are being tracked by the page reclaimer. */ #define SGX_EPC_PAGE_RECLAIMER_TRACKED BIT(0) @@ -101,12 +104,14 @@ struct sgx_epc_lru_lists { /* Must acquire this lock to access */ spinlock_t lock; struct list_head reclaimable; + struct list_head unreclaimable; }; static inline void sgx_lru_init(struct sgx_epc_lru_lists *lrus) { spin_lock_init(&lrus->lock); INIT_LIST_HEAD(&lrus->reclaimable); + INIT_LIST_HEAD(&lrus->unreclaimable); } struct sgx_epc_page *__sgx_alloc_epc_page(void);