From patchwork Mon Jun 12 04:25:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Roth X-Patchwork-Id: 13275480 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D493C7EE23 for ; Mon, 12 Jun 2023 04:34:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9AF8E6B0074; Mon, 12 Jun 2023 00:34:37 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 960108E0005; Mon, 12 Jun 2023 00:34:37 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7DAC78E0003; Mon, 12 Jun 2023 00:34:37 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 6B7946B0074 for ; Mon, 12 Jun 2023 00:34:37 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 475E680255 for ; Mon, 12 Jun 2023 04:34:37 +0000 (UTC) X-FDA: 80892829794.06.12CD65B Received: from NAM12-DM6-obe.outbound.protection.outlook.com (mail-dm6nam12on2076.outbound.protection.outlook.com [40.107.243.76]) by imf16.hostedemail.com (Postfix) with ESMTP id 0D83A180017 for ; Mon, 12 Jun 2023 04:34:33 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=3jUmAcJZ; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=quarantine) header.from=amd.com; spf=pass (imf16.hostedemail.com: domain of Michael.Roth@amd.com designates 40.107.243.76 as permitted sender) smtp.mailfrom=Michael.Roth@amd.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1686544474; a=rsa-sha256; cv=pass; b=bgExE0XCnEVypmqavyO3EfaIKixhPJAlU+Ks8fLnEHCAT0boI4N/qNLOS8AbWxRBQFkIiQ AuEi4V4moVjGnu2d4LXMRmUiDuTMFwdczagrxd6ZdgiWzeorUz3Wi25zc/7wE1ZfyMKsEB C4DYh1fcdQiWgIIX87sA6NVH5eUonc8= ARC-Authentication-Results: i=2; imf16.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=3jUmAcJZ; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=quarantine) header.from=amd.com; spf=pass (imf16.hostedemail.com: domain of Michael.Roth@amd.com designates 40.107.243.76 as permitted sender) smtp.mailfrom=Michael.Roth@amd.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1686544474; h=from:from:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=FtlNrZkBs+mDmj0lD3T2KGzFDdVu9lV4Sfe9JlYuGEc=; b=ndzVLJyggrZTwbFlfJEnbmPQYu9wBS+ti1chSV3UTR5GZn2Adw3F20NZD9YRdzITUlKVLY B+0djBhPs9wg4Fysy5jSg0eD4NG2lYNx6xWZasmmMuAlyH1cOOtBGmoKI2fYYzq+96Lc3b lVDYq69bXrQtZm6K+dvx9cPdMhC/JGE= ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=L4kJjcsIR5AhX8Q9VuuNAGKlqFZb7gmylOfq5ShJfOiqEmYwFsIU60DwpMCExMhcd7GOx7fKsaioLkYlztBZ4lfMhT/mXqKHwtSm4+fYkBQp31lSDnw8kbteoNGXL6WUmQNV+iZtwiySxp+J39/tm4Pks1Uo+nFA1MLfcSiqfn7ZJQ5eiSlMuYBtCrAlNzIdp9meZ8sJCIvww9vCDsW2h/1guVHE2FYyPE4KsbQWIbE458EzrAOzlxFt2wnqX9JFSPlIRd1ARDYU3EKLUMkzow0X+J60FBfzCueSKd1Ob12iqA0hT31or1P1JfXL7elJeweGdVnvQR6boeKZ67NVIg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=FtlNrZkBs+mDmj0lD3T2KGzFDdVu9lV4Sfe9JlYuGEc=; b=W3f2nMqdaQT0uZjw0gGd1njBfjp1bRJNG8/FXw2Ew8L5GB++tdrW1rfrpR6D0HewRn5BFfhF8u/H9d2pdqRYanZCaK8LkAMmCdx8MWompMevehtxfksD5/00PEbOnYLxp0FFfM+75xFRHiBcexvkdJJWZhLZZC+JLFDQyMN38X1F+ZUg3m4Qr8LkO+nOUzd0OB6O9Applri95L8T8o7hCUmKpe9s2/mktNfY1dtgxOU56SsCZ2FC5/K6bfjpfcxHovQ1LTUHpXLhJuUODtRCVxYWaGZaSeLS1AcQPztZEOL5Yxla0IeA3xBk4jjtMiMMclV5yNrxr++C+wM81muYAw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=vger.kernel.org smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=FtlNrZkBs+mDmj0lD3T2KGzFDdVu9lV4Sfe9JlYuGEc=; b=3jUmAcJZbc758CLRnNKO8b9lezHl48ZH9S11doolj5rSPdAk5qQs+ylOVb9vVoOAnetZ3VDcHMkHzp6IgqCJs0m/nQ0W93Yi8jY/2BLpqRm5tcbxV4qDeVd/wqLMtdKTsbySIQopG+xpRx4HloGboj5oWbv6ibSUxTxyasAMjaY= Received: from BY3PR03CA0005.namprd03.prod.outlook.com (2603:10b6:a03:39a::10) by BL1PR12MB5335.namprd12.prod.outlook.com (2603:10b6:208:317::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6455.38; Mon, 12 Jun 2023 04:34:30 +0000 Received: from DM6NAM11FT062.eop-nam11.prod.protection.outlook.com (2603:10b6:a03:39a:cafe::e4) by BY3PR03CA0005.outlook.office365.com (2603:10b6:a03:39a::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6477.33 via Frontend Transport; Mon, 12 Jun 2023 04:34:30 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C Received: from SATLEXMB04.amd.com (165.204.84.17) by DM6NAM11FT062.mail.protection.outlook.com (10.13.173.40) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.6500.21 via Frontend Transport; Mon, 12 Jun 2023 04:34:29 +0000 Received: from localhost (10.180.168.240) by SATLEXMB04.amd.com (10.181.40.145) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Sun, 11 Jun 2023 23:34:25 -0500 From: Michael Roth To: CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Brijesh Singh Subject: [PATCH RFC v9 21/51] crypto: ccp: Handle the legacy SEV command when SNP is enabled Date: Sun, 11 Jun 2023 23:25:29 -0500 Message-ID: <20230612042559.375660-22-michael.roth@amd.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230612042559.375660-1-michael.roth@amd.com> References: <20230612042559.375660-1-michael.roth@amd.com> MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB04.amd.com (10.181.40.145) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM6NAM11FT062:EE_|BL1PR12MB5335:EE_ X-MS-Office365-Filtering-Correlation-Id: 0d352f9b-ad2f-42b2-c8e9-08db6afe5009 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: DvPe/j7WtUOROF+vN0nk6wN9zCriPinr01iviun9TQtqQITNq7JHVipiJnL0nWsOB+xDi5ChSoDa7SA1NuDUDKTjfCEqKwNbK3XNuHCXkY3ezPKcs6Cr8iyQhRc6gCRU75OsVRhhe5DEsVmVa3dSF1V+N9x93Tk9cDcKqKmWRDTAFPpWgZhltHbgL98A3Y3JPE2+ipIcethfgQI42U7hLEOS/FgelsFzANRDwRMeftRuziaqxn/o+F2YmQqCetr4i03eFnxv7Dyzz9Th2k1eR4SMPgymfE1flsIrbo8xDk3nzKjW4J8lzoBPZj2wCF8kN0IoJ/hPbaOsaUId6PcKGC7lYCI0i50bT92r01+2+90hHicVk/QiN8zWn0HNk8XfP56PnG+J9R1T8KMEKPR7AALAsVRpn2AyxRwltlSSAInJs9fzFYalVw+HLDstMjvPYLKPtWykKM0T8xK2Tgo9PCTwPcwe5pv0AaAAv5PoGYct04XFQUvAIkKDqNQrxpU+o6kZB2qH0XKe4L8Xw8K7hwUBTCP8tXGYdI2AEaiS+uGC82jY//F0hHcDs+MpK7I3JYo9Ow/27lxN4LrCU5hRjMgifvhoR+mAIn9fa3xpyvfCiHliiKAzeXIzsPvTj2MVx2azGrjr6aH7bJ/J6Z0KKHYuDpeCvv+I9bd7GL3Te8nbvuPDp+HrNezDriYKbqJbQUhj85/UhSy24BakqdqQ7QYNgIJ8EQHOpwIa6fxRbwM0h3sk9ors4noDrZEWn5MAMHYVZ0eMS8I/Si31RQ9ibg== X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:SATLEXMB04.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230028)(4636009)(136003)(376002)(346002)(39860400002)(396003)(451199021)(36840700001)(40470700004)(46966006)(316002)(40460700003)(41300700001)(336012)(426003)(26005)(83380400001)(36860700001)(82310400005)(7416002)(186003)(16526019)(44832011)(47076005)(1076003)(7406005)(2616005)(2906002)(86362001)(30864003)(82740400003)(356005)(40480700001)(81166007)(36756003)(8936002)(8676002)(70206006)(70586007)(478600001)(5660300002)(54906003)(6916009)(4326008)(36900700001);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Jun 2023 04:34:29.9331 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 0d352f9b-ad2f-42b2-c8e9-08db6afe5009 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: DM6NAM11FT062.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5335 X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 0D83A180017 X-Stat-Signature: zm7g1znadub438ukqiwyrzh14jibx97n X-HE-Tag: 1686544473-533745 X-HE-Meta: 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 Rs9Ih/46 nmBdmz21kxmDVtVLCo5iYa2uU1iIOXigY/rcgdObHxbDqCvAVGkOk8KtdItUv5O8wGXWjdEkiQdqP/Yhst0j91MTFbJA9uzJTZ9arxC1vFUSXvKl6GYBQ4UYPT1IIkA8xn0N6phGNj/d0y+/N/LAAmL3uw1Xw9OxUhoiNzRhyCOu97DMpj3S6YerfOR5E8rE2onuThZNvT9b3cdwOL6ZuI51kCg3aLIJb5v624XSz+O948PbZnxHQl60j3ArOn7XBITwBRyyUI52AWKeO+Wui9yqfDw64XE31kP6CL8OB4Ni+8CxL53kWTR8Llg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Brijesh Singh The behavior of the SEV-legacy commands is altered when the SNP firmware is in the INIT state. When SNP is in INIT state, all the SEV-legacy commands that cause the firmware to write to memory must be in the firmware state before issuing the command.. A command buffer may contains a system physical address that the firmware may write to. There are two cases that need to be handled: 1) system physical address points to a guest memory 2) system physical address points to a host memory To handle the case #1, change the page state to the firmware in the RMP table before issuing the command and restore the state to shared after the command completes. For the case #2, use a bounce buffer to complete the request. Signed-off-by: Brijesh Singh Signed-off-by: Ashish Kalra Signed-off-by: Michael Roth --- drivers/crypto/ccp/sev-dev.c | 371 ++++++++++++++++++++++++++++++++++- drivers/crypto/ccp/sev-dev.h | 12 ++ 2 files changed, 373 insertions(+), 10 deletions(-) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index d8124d33c831..10bb0a7dcfd6 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -28,6 +28,7 @@ #include #include #include +#include #include "psp-dev.h" #include "sev-dev.h" @@ -258,6 +259,30 @@ static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, boo return rc; } +static int rmp_mark_pages_shared(unsigned long paddr, unsigned int npages) +{ + /* Cbit maybe set in the paddr */ + unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; + int rc, n = 0, i; + + for (i = 0; i < npages; i++, pfn++, n++) { + rc = rmp_make_shared(pfn, PG_LEVEL_4K); + if (rc) + goto cleanup; + } + + return 0; + +cleanup: + /* + * If failed to change the page state to shared, then its not safe + * to release the page back to the system, leak it. + */ + snp_leak_pages(pfn, npages - n); + + return rc; +} + static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order, bool locked) { unsigned long npages = 1ul << order, paddr; @@ -459,12 +484,295 @@ static int sev_write_init_ex_file_if_required(int cmd_id) return sev_write_init_ex_file(); } +static int alloc_snp_host_map(struct sev_device *sev) +{ + struct page *page; + int i; + + for (i = 0; i < MAX_SNP_HOST_MAP_BUFS; i++) { + struct snp_host_map *map = &sev->snp_host_map[i]; + + memset(map, 0, sizeof(*map)); + + page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(SEV_FW_BLOB_MAX_SIZE)); + if (!page) + return -ENOMEM; + + map->host = page_address(page); + } + + return 0; +} + +static void free_snp_host_map(struct sev_device *sev) +{ + int i; + + for (i = 0; i < MAX_SNP_HOST_MAP_BUFS; i++) { + struct snp_host_map *map = &sev->snp_host_map[i]; + + if (map->host) { + __free_pages(virt_to_page(map->host), get_order(SEV_FW_BLOB_MAX_SIZE)); + memset(map, 0, sizeof(*map)); + } + } +} + +static int map_firmware_writeable(u64 *paddr, u32 len, bool guest, struct snp_host_map *map) +{ + unsigned int npages = PAGE_ALIGN(len) >> PAGE_SHIFT; + + map->active = false; + + if (!paddr || !len) + return 0; + + map->paddr = *paddr; + map->len = len; + + /* If paddr points to a guest memory then change the page state to firmwware. */ + if (guest) { + if (rmp_mark_pages_firmware(*paddr, npages, true)) + return -EFAULT; + + goto done; + } + + if (!map->host) + return -ENOMEM; + + /* Check if the pre-allocated buffer can be used to fullfil the request. */ + if (len > SEV_FW_BLOB_MAX_SIZE) + return -EINVAL; + + /* Transition the pre-allocated buffer to the firmware state. */ + if (rmp_mark_pages_firmware(__pa(map->host), npages, true)) + return -EFAULT; + + /* Set the paddr to use pre-allocated firmware buffer */ + *paddr = __psp_pa(map->host); + +done: + map->active = true; + return 0; +} + +static int unmap_firmware_writeable(u64 *paddr, u32 len, bool guest, struct snp_host_map *map) +{ + unsigned int npages = PAGE_ALIGN(len) >> PAGE_SHIFT; + + if (!map->active) + return 0; + + /* If paddr points to a guest memory then restore the page state to hypervisor. */ + if (guest) { + if (snp_reclaim_pages(*paddr, npages, true)) + return -EFAULT; + + goto done; + } + + /* + * Transition the pre-allocated buffer to hypervisor state before the access. + * + * This is because while changing the page state to firmware, the kernel unmaps + * the pages from the direct map, and to restore the direct map the pages must + * be transitioned back to the shared state. + */ + if (snp_reclaim_pages(__pa(map->host), npages, true)) + return -EFAULT; + + /* Copy the response data firmware buffer to the callers buffer. */ + memcpy(__va(__sme_clr(map->paddr)), map->host, min_t(size_t, len, map->len)); + *paddr = map->paddr; + +done: + map->active = false; + return 0; +} + +static bool sev_legacy_cmd_buf_writable(int cmd) +{ + switch (cmd) { + case SEV_CMD_PLATFORM_STATUS: + case SEV_CMD_GUEST_STATUS: + case SEV_CMD_LAUNCH_START: + case SEV_CMD_RECEIVE_START: + case SEV_CMD_LAUNCH_MEASURE: + case SEV_CMD_SEND_START: + case SEV_CMD_SEND_UPDATE_DATA: + case SEV_CMD_SEND_UPDATE_VMSA: + case SEV_CMD_PEK_CSR: + case SEV_CMD_PDH_CERT_EXPORT: + case SEV_CMD_GET_ID: + case SEV_CMD_ATTESTATION_REPORT: + return true; + default: + return false; + } +} + +#define prep_buffer(name, addr, len, guest, map) \ + func(&((typeof(name *))cmd_buf)->addr, ((typeof(name *))cmd_buf)->len, guest, map) + +static int __snp_cmd_buf_copy(int cmd, void *cmd_buf, bool to_fw, int fw_err) +{ + int (*func)(u64 *paddr, u32 len, bool guest, struct snp_host_map *map); + struct sev_device *sev = psp_master->sev_data; + bool from_fw = !to_fw; + + /* + * After the command is completed, change the command buffer memory to + * hypervisor state. + * + * The immutable bit is automatically cleared by the firmware, so + * no not need to reclaim the page. + */ + if (from_fw && sev_legacy_cmd_buf_writable(cmd)) { + if (rmp_mark_pages_shared(__pa(cmd_buf), 1)) + return -EFAULT; + + /* No need to go further if firmware failed to execute command. */ + if (fw_err) + return 0; + } + + if (to_fw) + func = map_firmware_writeable; + else + func = unmap_firmware_writeable; + + /* + * A command buffer may contains a system physical address. If the address + * points to a host memory then use an intermediate firmware page otherwise + * change the page state in the RMP table. + */ + switch (cmd) { + case SEV_CMD_PDH_CERT_EXPORT: + if (prep_buffer(struct sev_data_pdh_cert_export, pdh_cert_address, + pdh_cert_len, false, &sev->snp_host_map[0])) + goto err; + if (prep_buffer(struct sev_data_pdh_cert_export, cert_chain_address, + cert_chain_len, false, &sev->snp_host_map[1])) + goto err; + break; + case SEV_CMD_GET_ID: + if (prep_buffer(struct sev_data_get_id, address, len, + false, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_PEK_CSR: + if (prep_buffer(struct sev_data_pek_csr, address, len, + false, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_LAUNCH_UPDATE_DATA: + if (prep_buffer(struct sev_data_launch_update_data, address, len, + true, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_LAUNCH_UPDATE_VMSA: + if (prep_buffer(struct sev_data_launch_update_vmsa, address, len, + true, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_LAUNCH_MEASURE: + if (prep_buffer(struct sev_data_launch_measure, address, len, + false, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_LAUNCH_UPDATE_SECRET: + if (prep_buffer(struct sev_data_launch_secret, guest_address, guest_len, + true, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_DBG_DECRYPT: + if (prep_buffer(struct sev_data_dbg, dst_addr, len, false, + &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_DBG_ENCRYPT: + if (prep_buffer(struct sev_data_dbg, dst_addr, len, true, + &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_ATTESTATION_REPORT: + if (prep_buffer(struct sev_data_attestation_report, address, len, + false, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_SEND_START: + if (prep_buffer(struct sev_data_send_start, session_address, + session_len, false, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_SEND_UPDATE_DATA: + if (prep_buffer(struct sev_data_send_update_data, hdr_address, hdr_len, + false, &sev->snp_host_map[0])) + goto err; + if (prep_buffer(struct sev_data_send_update_data, trans_address, + trans_len, false, &sev->snp_host_map[1])) + goto err; + break; + case SEV_CMD_SEND_UPDATE_VMSA: + if (prep_buffer(struct sev_data_send_update_vmsa, hdr_address, hdr_len, + false, &sev->snp_host_map[0])) + goto err; + if (prep_buffer(struct sev_data_send_update_vmsa, trans_address, + trans_len, false, &sev->snp_host_map[1])) + goto err; + break; + case SEV_CMD_RECEIVE_UPDATE_DATA: + if (prep_buffer(struct sev_data_receive_update_data, guest_address, + guest_len, true, &sev->snp_host_map[0])) + goto err; + break; + case SEV_CMD_RECEIVE_UPDATE_VMSA: + if (prep_buffer(struct sev_data_receive_update_vmsa, guest_address, + guest_len, true, &sev->snp_host_map[0])) + goto err; + break; + default: + break; + } + + /* The command buffer need to be in the firmware state. */ + if (to_fw && sev_legacy_cmd_buf_writable(cmd)) { + if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true)) + return -EFAULT; + } + + return 0; + +err: + return -EINVAL; +} + +static inline bool need_firmware_copy(int cmd) +{ + struct sev_device *sev = psp_master->sev_data; + + /* After SNP is INIT'ed, the behavior of legacy SEV command is changed. */ + return ((cmd < SEV_CMD_SNP_INIT) && sev->snp_initialized) ? true : false; +} + +static int snp_aware_copy_to_firmware(int cmd, void *data) +{ + return __snp_cmd_buf_copy(cmd, data, true, 0); +} + +static int snp_aware_copy_from_firmware(int cmd, void *data, int fw_err) +{ + return __snp_cmd_buf_copy(cmd, data, false, fw_err); +} + static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) { struct psp_device *psp = psp_master; struct sev_device *sev; unsigned int phys_lsb, phys_msb; unsigned int reg, ret = 0; + void *cmd_buf; int buf_len; if (!psp || !psp->sev_data) @@ -484,12 +792,28 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) * work for some memory, e.g. vmalloc'd addresses, and @data may not be * physically contiguous. */ - if (data) - memcpy(sev->cmd_buf, data, buf_len); + if (data) { + if (sev->cmd_buf_active > 2) + return -EBUSY; + + cmd_buf = sev->cmd_buf_active ? sev->cmd_buf_backup : sev->cmd_buf; + + memcpy(cmd_buf, data, buf_len); + sev->cmd_buf_active++; + + /* + * The behavior of the SEV-legacy commands is altered when the + * SNP firmware is in the INIT state. + */ + if (need_firmware_copy(cmd) && snp_aware_copy_to_firmware(cmd, cmd_buf)) + return -EFAULT; + } else { + cmd_buf = sev->cmd_buf; + } /* Get the physical address of the command buffer */ - phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0; - phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0; + phys_lsb = data ? lower_32_bits(__psp_pa(cmd_buf)) : 0; + phys_msb = data ? upper_32_bits(__psp_pa(cmd_buf)) : 0; dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", cmd, phys_msb, phys_lsb, psp_timeout); @@ -532,15 +856,24 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) ret = sev_write_init_ex_file_if_required(cmd); } - print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, - buf_len, false); - /* * Copy potential output from the PSP back to data. Do this even on * failure in case the caller wants to glean something from the error. */ - if (data) - memcpy(data, sev->cmd_buf, buf_len); + if (data) { + /* + * Restore the page state after the command completes. + */ + if (need_firmware_copy(cmd) && + snp_aware_copy_from_firmware(cmd, cmd_buf, ret)) + return -EFAULT; + + memcpy(data, cmd_buf, buf_len); + sev->cmd_buf_active--; + } + + print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, + buf_len, false); return ret; } @@ -624,6 +957,14 @@ static int __sev_platform_init_locked(int *error) dev_err(sev->dev, "SEV-SNP: failed to INIT rc %d, error %#x\n", rc, *error); } + /* + * Allocate the intermediate buffers used for the legacy command handling. + */ + if (rc != -ENODEV && alloc_snp_host_map(sev)) { + dev_notice(sev->dev, "Failed to alloc host map (disabling legacy SEV)\n"); + goto skip_legacy; + } + if (!sev_es_tmr) { /* Obtain the TMR memory area for SEV-ES use */ sev_es_tmr = sev_fw_alloc(sev_es_tmr_size); @@ -677,6 +1018,7 @@ static int __sev_platform_init_locked(int *error) dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, sev->api_minor, sev->build); +skip_legacy: return 0; } @@ -1586,10 +1928,12 @@ int sev_dev_init(struct psp_device *psp) if (!sev) goto e_err; - sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0); + sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 1); if (!sev->cmd_buf) goto e_sev; + sev->cmd_buf_backup = (uint8_t *)sev->cmd_buf + PAGE_SIZE; + psp->sev_data = sev; sev->dev = dev; @@ -1655,6 +1999,12 @@ static void sev_firmware_shutdown(struct sev_device *sev) snp_range_list = NULL; } + /* + * The host map need to clear the immutable bit so it must be free'd before the + * SNP firmware shutdown. + */ + free_snp_host_map(sev); + sev_snp_shutdown(&error); } @@ -1726,6 +2076,7 @@ void sev_pci_init(void) return; err: + free_snp_host_map(sev); psp_master->sev_data = NULL; } diff --git a/drivers/crypto/ccp/sev-dev.h b/drivers/crypto/ccp/sev-dev.h index 34767657beb5..19d79f9d4212 100644 --- a/drivers/crypto/ccp/sev-dev.h +++ b/drivers/crypto/ccp/sev-dev.h @@ -29,11 +29,20 @@ #define SEV_CMDRESP_CMD_SHIFT 16 #define SEV_CMDRESP_IOC BIT(0) +#define MAX_SNP_HOST_MAP_BUFS 2 + struct sev_misc_dev { struct kref refcount; struct miscdevice misc; }; +struct snp_host_map { + u64 paddr; + u32 len; + void *host; + bool active; +}; + struct sev_device { struct device *dev; struct psp_device *psp; @@ -52,8 +61,11 @@ struct sev_device { u8 build; void *cmd_buf; + void *cmd_buf_backup; + int cmd_buf_active; bool snp_initialized; + struct snp_host_map snp_host_map[MAX_SNP_HOST_MAP_BUFS]; }; int sev_dev_init(struct psp_device *psp);