// SPDX-License-Identifier: GPL-2.0-only /* * AMD Secure Encrypted Virtualization (SEV) interface * * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. * * Author: Brijesh Singh */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "psp-dev.h" #include "sev-dev.h" #define DEVICE_NAME "sev" #define SEV_FW_FILE "amd/sev.fw" #define SEV_FW_NAME_SIZE 64 /* Minimum firmware version required for the SEV-SNP support */ #define SNP_MIN_API_MAJOR 1 #define SNP_MIN_API_MINOR 51 /* * Maximum number of firmware-writable buffers that might be specified * in the parameters of a legacy SEV command buffer. */ #define CMD_BUF_FW_WRITABLE_MAX 2 /* Leave room in the descriptor array for an end-of-list indicator. */ #define CMD_BUF_DESC_MAX (CMD_BUF_FW_WRITABLE_MAX + 1) static DEFINE_MUTEX(sev_cmd_mutex); static struct sev_misc_dev *misc_dev; static int psp_cmd_timeout = 100; module_param(psp_cmd_timeout, int, 0644); MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); static int psp_probe_timeout = 5; module_param(psp_probe_timeout, int, 0644); MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); static char *init_ex_path; module_param(init_ex_path, charp, 0444); MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); static bool psp_init_on_probe = true; module_param(psp_init_on_probe, bool, 0444); MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */ static bool psp_dead; static int psp_timeout; /* Trusted Memory Region (TMR): * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator * to allocate the memory, which will return aligned memory for the specified * allocation order. * * When SEV-SNP is enabled the TMR needs to be 2MB aligned and 2MB sized. */ #define SEV_TMR_SIZE (1024 * 1024) #define SNP_TMR_SIZE (2 * 1024 * 1024) static void *sev_es_tmr; static size_t sev_es_tmr_size = SEV_TMR_SIZE; /* INIT_EX NV Storage: * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page * allocator to allocate the memory, which will return aligned memory for the * specified allocation order. */ #define NV_LENGTH (32 * 1024) static void *sev_init_ex_buffer; /* * SEV_DATA_RANGE_LIST: * Array containing range of pages that firmware transitions to HV-fixed * page state. */ static struct sev_data_range_list *snp_range_list; static inline bool sev_version_greater_or_equal(u8 maj, u8 min) { struct sev_device *sev = psp_master->sev_data; if (sev->api_major > maj) return true; if (sev->api_major == maj && sev->api_minor >= min) return true; return false; } static void sev_irq_handler(int irq, void *data, unsigned int status) { struct sev_device *sev = data; int reg; /* Check if it is command completion: */ if (!(status & SEV_CMD_COMPLETE)) return; /* Check if it is SEV command completion: */ reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); if (FIELD_GET(PSP_CMDRESP_RESP, reg)) { sev->int_rcvd = 1; wake_up(&sev->int_queue); } } static int sev_wait_cmd_ioc(struct sev_device *sev, unsigned int *reg, unsigned int timeout) { int ret; /* * If invoked during panic handling, local interrupts are disabled, * so the PSP command completion interrupt can't be used. Poll for * PSP command completion instead. */ if (irqs_disabled()) { unsigned long timeout_usecs = (timeout * USEC_PER_SEC) / 10; /* Poll for SEV command completion: */ while (timeout_usecs--) { *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); if (*reg & PSP_CMDRESP_RESP) return 0; udelay(10); } return -ETIMEDOUT; } ret = wait_event_timeout(sev->int_queue, sev->int_rcvd, timeout * HZ); if (!ret) return -ETIMEDOUT; *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); return 0; } static int sev_cmd_buffer_len(int cmd) { switch (cmd) { case SEV_CMD_INIT: return sizeof(struct sev_data_init); case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); case SEV_CMD_SNP_SHUTDOWN_EX: return sizeof(struct sev_data_snp_shutdown_ex); case SEV_CMD_SNP_INIT_EX: return sizeof(struct sev_data_snp_init_ex); case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); case SEV_CMD_SNP_GCTX_CREATE: return sizeof(struct sev_data_snp_addr); case SEV_CMD_SNP_LAUNCH_START: return sizeof(struct sev_data_snp_launch_start); case SEV_CMD_SNP_LAUNCH_UPDATE: return sizeof(struct sev_data_snp_launch_update); case SEV_CMD_SNP_ACTIVATE: return sizeof(struct sev_data_snp_activate); case SEV_CMD_SNP_DECOMMISSION: return sizeof(struct sev_data_snp_addr); case SEV_CMD_SNP_PAGE_RECLAIM: return sizeof(struct sev_data_snp_page_reclaim); case SEV_CMD_SNP_GUEST_STATUS: return sizeof(struct sev_data_snp_guest_status); case SEV_CMD_SNP_LAUNCH_FINISH: return sizeof(struct sev_data_snp_launch_finish); case SEV_CMD_SNP_DBG_DECRYPT: return sizeof(struct sev_data_snp_dbg); case SEV_CMD_SNP_DBG_ENCRYPT: return sizeof(struct sev_data_snp_dbg); case SEV_CMD_SNP_PAGE_UNSMASH: return sizeof(struct sev_data_snp_page_unsmash); case SEV_CMD_SNP_PLATFORM_STATUS: return sizeof(struct sev_data_snp_addr); case SEV_CMD_SNP_GUEST_REQUEST: return sizeof(struct sev_data_snp_guest_request); case SEV_CMD_SNP_CONFIG: return sizeof(struct sev_user_data_snp_config); case SEV_CMD_SNP_COMMIT: return sizeof(struct sev_data_snp_commit); default: return 0; } return 0; } static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) { struct file *fp; struct path root; struct cred *cred; const struct cred *old_cred; task_lock(&init_task); get_fs_root(init_task.fs, &root); task_unlock(&init_task); cred = prepare_creds(); if (!cred) return ERR_PTR(-ENOMEM); cred->fsuid = GLOBAL_ROOT_UID; old_cred = override_creds(cred); fp = file_open_root(&root, filename, flags, mode); path_put(&root); revert_creds(old_cred); return fp; } static int sev_read_init_ex_file(void) { struct sev_device *sev = psp_master->sev_data; struct file *fp; ssize_t nread; lockdep_assert_held(&sev_cmd_mutex); if (!sev_init_ex_buffer) return -EOPNOTSUPP; fp = open_file_as_root(init_ex_path, O_RDONLY, 0); if (IS_ERR(fp)) { int ret = PTR_ERR(fp); if (ret == -ENOENT) { dev_info(sev->dev, "SEV: %s does not exist and will be created later.\n", init_ex_path); ret = 0; } else { dev_err(sev->dev, "SEV: could not open %s for read, error %d\n", init_ex_path, ret); } return ret; } nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); if (nread != NV_LENGTH) { dev_info(sev->dev, "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", NV_LENGTH, nread); } dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); filp_close(fp, NULL); return 0; } static int sev_write_init_ex_file(void) { struct sev_device *sev = psp_master->sev_data; struct file *fp; loff_t offset = 0; ssize_t nwrite; lockdep_assert_held(&sev_cmd_mutex); if (!sev_init_ex_buffer) return 0; fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); if (IS_ERR(fp)) { int ret = PTR_ERR(fp); dev_err(sev->dev, "SEV: could not open file for write, error %d\n", ret); return ret; } nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); vfs_fsync(fp, 0); filp_close(fp, NULL); if (nwrite != NV_LENGTH) { dev_err(sev->dev, "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", NV_LENGTH, nwrite); return -EIO; } dev_dbg(sev->dev, "SEV: write successful to NV file\n"); return 0; } static int sev_write_init_ex_file_if_required(int cmd_id) { lockdep_assert_held(&sev_cmd_mutex); if (!sev_init_ex_buffer) return 0; /* * Only a few platform commands modify the SPI/NV area, but none of the * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, * PEK_CERT_IMPORT, and PDH_GEN do. */ switch (cmd_id) { case SEV_CMD_FACTORY_RESET: case SEV_CMD_INIT_EX: case SEV_CMD_PDH_GEN: case SEV_CMD_PEK_CERT_IMPORT: case SEV_CMD_PEK_GEN: break; default: return 0; } return sev_write_init_ex_file(); } /* * snp_reclaim_pages() needs __sev_do_cmd_locked(), and __sev_do_cmd_locked() * needs snp_reclaim_pages(), so a forward declaration is needed. */ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret); static int snp_reclaim_pages(unsigned long paddr, unsigned int npages, bool locked) { int ret, err, i; paddr = __sme_clr(ALIGN_DOWN(paddr, PAGE_SIZE)); for (i = 0; i < npages; i++, paddr += PAGE_SIZE) { struct sev_data_snp_page_reclaim data = {0}; data.paddr = paddr; if (locked) ret = __sev_do_cmd_locked(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); else ret = sev_do_cmd(SEV_CMD_SNP_PAGE_RECLAIM, &data, &err); if (ret) goto cleanup; ret = rmp_make_shared(__phys_to_pfn(paddr), PG_LEVEL_4K); if (ret) goto cleanup; } return 0; cleanup: /* * If there was a failure reclaiming the page then it is no longer safe * to release it back to the system; leak it instead. */ snp_leak_pages(__phys_to_pfn(paddr), npages - i); return ret; } static int rmp_mark_pages_firmware(unsigned long paddr, unsigned int npages, bool locked) { unsigned long pfn = __sme_clr(paddr) >> PAGE_SHIFT; int rc, i; for (i = 0; i < npages; i++, pfn++) { rc = rmp_make_private(pfn, 0, PG_LEVEL_4K, 0, true); if (rc) goto cleanup; } return 0; cleanup: /* * Try unrolling the firmware state changes by * reclaiming the pages which were already changed to the * firmware state. */ snp_reclaim_pages(paddr, i, locked); return rc; } static struct page *__snp_alloc_firmware_pages(gfp_t gfp_mask, int order) { unsigned long npages = 1ul << order, paddr; struct sev_device *sev; struct page *page; if (!psp_master || !psp_master->sev_data) return NULL; page = alloc_pages(gfp_mask, order); if (!page) return NULL; /* If SEV-SNP is initialized then add the page in RMP table. */ sev = psp_master->sev_data; if (!sev->snp_initialized) return page; paddr = __pa((unsigned long)page_address(page)); if (rmp_mark_pages_firmware(paddr, npages, false)) return NULL; return page; } void *snp_alloc_firmware_page(gfp_t gfp_mask) { struct page *page; page = __snp_alloc_firmware_pages(gfp_mask, 0); return page ? page_address(page) : NULL; } EXPORT_SYMBOL_GPL(snp_alloc_firmware_page); static void __snp_free_firmware_pages(struct page *page, int order, bool locked) { struct sev_device *sev = psp_master->sev_data; unsigned long paddr, npages = 1ul << order; if (!page) return; paddr = __pa((unsigned long)page_address(page)); if (sev->snp_initialized && snp_reclaim_pages(paddr, npages, locked)) return; __free_pages(page, order); } void snp_free_firmware_page(void *addr) { if (!addr) return; __snp_free_firmware_pages(virt_to_page(addr), 0, false); } EXPORT_SYMBOL_GPL(snp_free_firmware_page); static void *sev_fw_alloc(unsigned long len) { struct page *page; page = __snp_alloc_firmware_pages(GFP_KERNEL, get_order(len)); if (!page) return NULL; return page_address(page); } /** * struct cmd_buf_desc - descriptors for managing legacy SEV command address * parameters corresponding to buffers that may be written to by firmware. * * @paddr_ptr: pointer to the address parameter in the command buffer which may * need to be saved/restored depending on whether a bounce buffer * is used. In the case of a bounce buffer, the command buffer * needs to be updated with the address of the new bounce buffer * snp_map_cmd_buf_desc() has allocated specifically for it. Must * be NULL if this descriptor is only an end-of-list indicator. * * @paddr_orig: storage for the original address parameter, which can be used to * restore the original value in @paddr_ptr in cases where it is * replaced with the address of a bounce buffer. * * @len: length of buffer located at the address originally stored at @paddr_ptr * * @guest_owned: true if the address corresponds to guest-owned pages, in which * case bounce buffers are not needed. */ struct cmd_buf_desc { u64 *paddr_ptr; u64 paddr_orig; u32 len; bool guest_owned; }; /* * If a legacy SEV command parameter is a memory address, those pages in * turn need to be transitioned to/from firmware-owned before/after * executing the firmware command. * * Additionally, in cases where those pages are not guest-owned, a bounce * buffer is needed in place of the original memory address parameter. * * A set of descriptors are used to keep track of this handling, and * initialized here based on the specific commands being executed. */ static void snp_populate_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) { switch (cmd) { case SEV_CMD_PDH_CERT_EXPORT: { struct sev_data_pdh_cert_export *data = cmd_buf; desc_list[0].paddr_ptr = &data->pdh_cert_address; desc_list[0].len = data->pdh_cert_len; desc_list[1].paddr_ptr = &data->cert_chain_address; desc_list[1].len = data->cert_chain_len; break; } case SEV_CMD_GET_ID: { struct sev_data_get_id *data = cmd_buf; desc_list[0].paddr_ptr = &data->address; desc_list[0].len = data->len; break; } case SEV_CMD_PEK_CSR: { struct sev_data_pek_csr *data = cmd_buf; desc_list[0].paddr_ptr = &data->address; desc_list[0].len = data->len; break; } case SEV_CMD_LAUNCH_UPDATE_DATA: { struct sev_data_launch_update_data *data = cmd_buf; desc_list[0].paddr_ptr = &data->address; desc_list[0].len = data->len; desc_list[0].guest_owned = true; break; } case SEV_CMD_LAUNCH_UPDATE_VMSA: { struct sev_data_launch_update_vmsa *data = cmd_buf; desc_list[0].paddr_ptr = &data->address; desc_list[0].len = data->len; desc_list[0].guest_owned = true; break; } case SEV_CMD_LAUNCH_MEASURE: { struct sev_data_launch_measure *data = cmd_buf; desc_list[0].paddr_ptr = &data->address; desc_list[0].len = data->len; break; } case SEV_CMD_LAUNCH_UPDATE_SECRET: { struct sev_data_launch_secret *data = cmd_buf; desc_list[0].paddr_ptr = &data->guest_address; desc_list[0].len = data->guest_len; desc_list[0].guest_owned = true; break; } case SEV_CMD_DBG_DECRYPT: { struct sev_data_dbg *data = cmd_buf; desc_list[0].paddr_ptr = &data->dst_addr; desc_list[0].len = data->len; desc_list[0].guest_owned = true; break; } case SEV_CMD_DBG_ENCRYPT: { struct sev_data_dbg *data = cmd_buf; desc_list[0].paddr_ptr = &data->dst_addr; desc_list[0].len = data->len; desc_list[0].guest_owned = true; break; } case SEV_CMD_ATTESTATION_REPORT: { struct sev_data_attestation_report *data = cmd_buf; desc_list[0].paddr_ptr = &data->address; desc_list[0].len = data->len; break; } case SEV_CMD_SEND_START: { struct sev_data_send_start *data = cmd_buf; desc_list[0].paddr_ptr = &data->session_address; desc_list[0].len = data->session_len; break; } case SEV_CMD_SEND_UPDATE_DATA: { struct sev_data_send_update_data *data = cmd_buf; desc_list[0].paddr_ptr = &data->hdr_address; desc_list[0].len = data->hdr_len; desc_list[1].paddr_ptr = &data->trans_address; desc_list[1].len = data->trans_len; break; } case SEV_CMD_SEND_UPDATE_VMSA: { struct sev_data_send_update_vmsa *data = cmd_buf; desc_list[0].paddr_ptr = &data->hdr_address; desc_list[0].len = data->hdr_len; desc_list[1].paddr_ptr = &data->trans_address; desc_list[1].len = data->trans_len; break; } case SEV_CMD_RECEIVE_UPDATE_DATA: { struct sev_data_receive_update_data *data = cmd_buf; desc_list[0].paddr_ptr = &data->guest_address; desc_list[0].len = data->guest_len; desc_list[0].guest_owned = true; break; } case SEV_CMD_RECEIVE_UPDATE_VMSA: { struct sev_data_receive_update_vmsa *data = cmd_buf; desc_list[0].paddr_ptr = &data->guest_address; desc_list[0].len = data->guest_len; desc_list[0].guest_owned = true; break; } default: break; } } static int snp_map_cmd_buf_desc(struct cmd_buf_desc *desc) { unsigned int npages; if (!desc->len) return 0; /* Allocate a bounce buffer if this isn't a guest owned page. */ if (!desc->guest_owned) { struct page *page; page = alloc_pages(GFP_KERNEL_ACCOUNT, get_order(desc->len)); if (!page) { pr_warn("Failed to allocate bounce buffer for SEV legacy command.\n"); return -ENOMEM; } desc->paddr_orig = *desc->paddr_ptr; *desc->paddr_ptr = __psp_pa(page_to_virt(page)); } npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; /* Transition the buffer to firmware-owned. */ if (rmp_mark_pages_firmware(*desc->paddr_ptr, npages, true)) { pr_warn("Error moving pages to firmware-owned state for SEV legacy command.\n"); return -EFAULT; } return 0; } static int snp_unmap_cmd_buf_desc(struct cmd_buf_desc *desc) { unsigned int npages; if (!desc->len) return 0; npages = PAGE_ALIGN(desc->len) >> PAGE_SHIFT; /* Transition the buffers back to hypervisor-owned. */ if (snp_reclaim_pages(*desc->paddr_ptr, npages, true)) { pr_warn("Failed to reclaim firmware-owned pages while issuing SEV legacy command.\n"); return -EFAULT; } /* Copy data from bounce buffer and then free it. */ if (!desc->guest_owned) { void *bounce_buf = __va(__sme_clr(*desc->paddr_ptr)); void *dst_buf = __va(__sme_clr(desc->paddr_orig)); memcpy(dst_buf, bounce_buf, desc->len); __free_pages(virt_to_page(bounce_buf), get_order(desc->len)); /* Restore the original address in the command buffer. */ *desc->paddr_ptr = desc->paddr_orig; } return 0; } static int snp_map_cmd_buf_desc_list(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) { int i; snp_populate_cmd_buf_desc_list(cmd, cmd_buf, desc_list); for (i = 0; i < CMD_BUF_DESC_MAX; i++) { struct cmd_buf_desc *desc = &desc_list[i]; if (!desc->paddr_ptr) break; if (snp_map_cmd_buf_desc(desc)) goto err_unmap; } return 0; err_unmap: for (i--; i >= 0; i--) snp_unmap_cmd_buf_desc(&desc_list[i]); return -EFAULT; } static int snp_unmap_cmd_buf_desc_list(struct cmd_buf_desc *desc_list) { int i, ret = 0; for (i = 0; i < CMD_BUF_DESC_MAX; i++) { struct cmd_buf_desc *desc = &desc_list[i]; if (!desc->paddr_ptr) break; if (snp_unmap_cmd_buf_desc(&desc_list[i])) ret = -EFAULT; } return ret; } static bool sev_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; } } /* After SNP is INIT'ed, the behavior of legacy SEV commands is changed. */ static bool snp_legacy_handling_needed(int cmd) { struct sev_device *sev = psp_master->sev_data; return cmd < SEV_CMD_SNP_INIT && sev->snp_initialized; } static int snp_prep_cmd_buf(int cmd, void *cmd_buf, struct cmd_buf_desc *desc_list) { if (!snp_legacy_handling_needed(cmd)) return 0; if (snp_map_cmd_buf_desc_list(cmd, cmd_buf, desc_list)) return -EFAULT; /* * Before command execution, the command buffer needs to be put into * the firmware-owned state. */ if (sev_cmd_buf_writable(cmd)) { if (rmp_mark_pages_firmware(__pa(cmd_buf), 1, true)) return -EFAULT; } return 0; } static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf) { if (!snp_legacy_handling_needed(cmd)) return 0; /* * After command completion, the command buffer needs to be put back * into the hypervisor-owned state. */ if (sev_cmd_buf_writable(cmd)) if (snp_reclaim_pages(__pa(cmd_buf), 1, true)) return -EFAULT; return 0; } static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) { struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0}; struct psp_device *psp = psp_master; struct sev_device *sev; unsigned int cmdbuff_hi, cmdbuff_lo; unsigned int phys_lsb, phys_msb; unsigned int reg, ret = 0; void *cmd_buf; int buf_len; if (!psp || !psp->sev_data) return -ENODEV; if (psp_dead) return -EBUSY; sev = psp->sev_data; buf_len = sev_cmd_buffer_len(cmd); if (WARN_ON_ONCE(!data != !buf_len)) return -EINVAL; /* * Copy the incoming data to driver's scratch buffer as __pa() will not * work for some memory, e.g. vmalloc'd addresses, and @data may not be * physically contiguous. */ if (data) { /* * Commands are generally issued one at a time and require the * sev_cmd_mutex, but there could be recursive firmware requests * due to SEV_CMD_SNP_PAGE_RECLAIM needing to be issued while * preparing buffers for another command. This is the only known * case of nesting in the current code, so exactly one * additional command buffer is available for that purpose. */ if (!sev->cmd_buf_active) { cmd_buf = sev->cmd_buf; sev->cmd_buf_active = true; } else if (!sev->cmd_buf_backup_active) { cmd_buf = sev->cmd_buf_backup; sev->cmd_buf_backup_active = true; } else { dev_err(sev->dev, "SEV: too many firmware commands in progress, no command buffers available.\n"); return -EBUSY; } memcpy(cmd_buf, data, buf_len); /* * The behavior of the SEV-legacy commands is altered when the * SNP firmware is in the INIT state. */ ret = snp_prep_cmd_buf(cmd, cmd_buf, desc_list); if (ret) { dev_err(sev->dev, "SEV: failed to prepare buffer for legacy command 0x%x. Error: %d\n", cmd, ret); return ret; } } else { cmd_buf = sev->cmd_buf; } /* Get the physical address of the command buffer */ 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); print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, buf_len, false); iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); sev->int_rcvd = 0; reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd) | SEV_CMDRESP_IOC; iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); /* wait for command completion */ ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); if (ret) { if (psp_ret) *psp_ret = 0; dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); psp_dead = true; return ret; } psp_timeout = psp_cmd_timeout; if (psp_ret) *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); if (FIELD_GET(PSP_CMDRESP_STS, reg)) { dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); /* * PSP firmware may report additional error information in the * command buffer registers on error. Print contents of command * buffer registers if they changed. */ cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) { dev_dbg(sev->dev, "Additional error information reported in cmdbuff:"); dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi); dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo); } ret = -EIO; } else { ret = sev_write_init_ex_file_if_required(cmd); } /* * 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) { int ret_reclaim; /* * Restore the page state after the command completes. */ ret_reclaim = snp_reclaim_cmd_buf(cmd, cmd_buf); if (ret_reclaim) { dev_err(sev->dev, "SEV: failed to reclaim buffer for legacy command %#x. Error: %d\n", cmd, ret_reclaim); return ret_reclaim; } memcpy(data, cmd_buf, buf_len); if (sev->cmd_buf_backup_active) sev->cmd_buf_backup_active = false; else sev->cmd_buf_active = false; if (snp_unmap_cmd_buf_desc_list(desc_list)) return -EFAULT; } print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, buf_len, false); return ret; } int sev_do_cmd(int cmd, void *data, int *psp_ret) { int rc; mutex_lock(&sev_cmd_mutex); rc = __sev_do_cmd_locked(cmd, data, psp_ret); mutex_unlock(&sev_cmd_mutex); return rc; } EXPORT_SYMBOL_GPL(sev_do_cmd); static int __sev_init_locked(int *error) { struct sev_data_init data; memset(&data, 0, sizeof(data)); if (sev_es_tmr) { /* * Do not include the encryption mask on the physical * address of the TMR (firmware should clear it anyway). */ data.tmr_address = __pa(sev_es_tmr); data.flags |= SEV_INIT_FLAGS_SEV_ES; data.tmr_len = sev_es_tmr_size; } return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); } static int __sev_init_ex_locked(int *error) { struct sev_data_init_ex data; memset(&data, 0, sizeof(data)); data.length = sizeof(data); data.nv_address = __psp_pa(sev_init_ex_buffer); data.nv_len = NV_LENGTH; if (sev_es_tmr) { /* * Do not include the encryption mask on the physical * address of the TMR (firmware should clear it anyway). */ data.tmr_address = __pa(sev_es_tmr); data.flags |= SEV_INIT_FLAGS_SEV_ES; data.tmr_len = sev_es_tmr_size; } return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); } static inline int __sev_do_init_locked(int *psp_ret) { if (sev_init_ex_buffer) return __sev_init_ex_locked(psp_ret); else return __sev_init_locked(psp_ret); } static void snp_set_hsave_pa(void *arg) { wrmsrl(MSR_VM_HSAVE_PA, 0); } static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg) { struct sev_data_range_list *range_list = arg; struct sev_data_range *range = &range_list->ranges[range_list->num_elements]; size_t size; /* * Ensure the list of HV_FIXED pages that will be passed to firmware * do not exceed the page-sized argument buffer. */ if ((range_list->num_elements * sizeof(struct sev_data_range) + sizeof(struct sev_data_range_list)) > PAGE_SIZE) return -E2BIG; switch (rs->desc) { case E820_TYPE_RESERVED: case E820_TYPE_PMEM: case E820_TYPE_ACPI: range->base = rs->start & PAGE_MASK; size = PAGE_ALIGN((rs->end + 1) - rs->start); range->page_count = size >> PAGE_SHIFT; range_list->num_elements++; break; default: break; } return 0; } static int __sev_snp_init_locked(int *error) { struct psp_device *psp = psp_master; struct sev_data_snp_init_ex data; struct sev_device *sev; void *arg = &data; int cmd, rc = 0; if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) return -ENODEV; sev = psp->sev_data; if (sev->snp_initialized) return 0; if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) { dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n", SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR); return 0; } /* SNP_INIT requires MSR_VM_HSAVE_PA to be cleared on all CPUs. */ on_each_cpu(snp_set_hsave_pa, NULL, 1); /* * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list * of system physical address ranges to convert into HV-fixed page * states during the RMP initialization. For instance, the memory that * UEFI reserves should be included in the that list. This allows system * components that occasionally write to memory (e.g. logging to UEFI * reserved regions) to not fail due to RMP initialization and SNP * enablement. * */ if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) { /* * Firmware checks that the pages containing the ranges enumerated * in the RANGES structure are either in the default page state or in the * firmware page state. */ snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL); if (!snp_range_list) { dev_err(sev->dev, "SEV: SNP_INIT_EX range list memory allocation failed\n"); return -ENOMEM; } /* * Retrieve all reserved memory regions from the e820 memory map * to be setup as HV-fixed pages. */ rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0, snp_range_list, snp_filter_reserved_mem_regions); if (rc) { dev_err(sev->dev, "SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc); return rc; } memset(&data, 0, sizeof(data)); data.init_rmp = 1; data.list_paddr_en = 1; data.list_paddr = __psp_pa(snp_range_list); cmd = SEV_CMD_SNP_INIT_EX; } else { cmd = SEV_CMD_SNP_INIT; arg = NULL; } /* * The following sequence must be issued before launching the first SNP * guest to ensure all dirty cache lines are flushed, including from * updates to the RMP table itself via the RMPUPDATE instruction: * * - WBINVD on all running CPUs * - SEV_CMD_SNP_INIT[_EX] firmware command * - WBINVD on all running CPUs * - SEV_CMD_SNP_DF_FLUSH firmware command */ wbinvd_on_all_cpus(); rc = __sev_do_cmd_locked(cmd, arg, error); if (rc) return rc; /* Prepare for first SNP guest launch after INIT. */ wbinvd_on_all_cpus(); rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error); if (rc) return rc; sev->snp_initialized = true; dev_dbg(sev->dev, "SEV-SNP firmware initialized\n"); sev_es_tmr_size = SNP_TMR_SIZE; return rc; } static void __sev_platform_init_handle_tmr(struct sev_device *sev) { if (sev_es_tmr) return; /* Obtain the TMR memory area for SEV-ES use */ sev_es_tmr = sev_fw_alloc(sev_es_tmr_size); if (sev_es_tmr) { /* Must flush the cache before giving it to the firmware */ if (!sev->snp_initialized) clflush_cache_range(sev_es_tmr, sev_es_tmr_size); } else { dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n"); } } /* * If an init_ex_path is provided allocate a buffer for the file and * read in the contents. Additionally, if SNP is initialized, convert * the buffer pages to firmware pages. */ static int __sev_platform_init_handle_init_ex_path(struct sev_device *sev) { struct page *page; int rc; if (!init_ex_path) return 0; if (sev_init_ex_buffer) return 0; page = alloc_pages(GFP_KERNEL, get_order(NV_LENGTH)); if (!page) { dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n"); return -ENOMEM; } sev_init_ex_buffer = page_address(page); rc = sev_read_init_ex_file(); if (rc) return rc; /* If SEV-SNP is initialized, transition to firmware page. */ if (sev->snp_initialized) { unsigned long npages; npages = 1UL << get_order(NV_LENGTH); if (rmp_mark_pages_firmware(__pa(sev_init_ex_buffer), npages, false)) { dev_err(sev->dev, "SEV: INIT_EX NV memory page state change failed.\n"); return -ENOMEM; } } return 0; } static int __sev_platform_init_locked(int *error) { int rc, psp_ret = SEV_RET_NO_FW_CALL; struct sev_device *sev; if (!psp_master || !psp_master->sev_data) return -ENODEV; sev = psp_master->sev_data; if (sev->state == SEV_STATE_INIT) return 0; __sev_platform_init_handle_tmr(sev); rc = __sev_platform_init_handle_init_ex_path(sev); if (rc) return rc; rc = __sev_do_init_locked(&psp_ret); if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { /* * Initialization command returned an integrity check failure * status code, meaning that firmware load and validation of SEV * related persistent data has failed. Retrying the * initialization function should succeed by replacing the state * with a reset state. */ dev_err(sev->dev, "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); rc = __sev_do_init_locked(&psp_ret); } if (error) *error = psp_ret; if (rc) return rc; sev->state = SEV_STATE_INIT; /* Prepare for first SEV guest launch after INIT */ wbinvd_on_all_cpus(); rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error); if (rc) return rc; dev_dbg(sev->dev, "SEV firmware initialized\n"); dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, sev->api_minor, sev->build); return 0; } static int _sev_platform_init_locked(struct sev_platform_init_args *args) { struct sev_device *sev; int rc; if (!psp_master || !psp_master->sev_data) return -ENODEV; sev = psp_master->sev_data; if (sev->state == SEV_STATE_INIT) return 0; /* * Legacy guests cannot be running while SNP_INIT(_EX) is executing, * so perform SEV-SNP initialization at probe time. */ rc = __sev_snp_init_locked(&args->error); if (rc && rc != -ENODEV) { /* * Don't abort the probe if SNP INIT failed, * continue to initialize the legacy SEV firmware. */ dev_err(sev->dev, "SEV-SNP: failed to INIT rc %d, error %#x\n", rc, args->error); } /* Defer legacy SEV/SEV-ES support if allowed by caller/module. */ if (args->probe && !psp_init_on_probe) return 0; return __sev_platform_init_locked(&args->error); } int sev_platform_init(struct sev_platform_init_args *args) { int rc; mutex_lock(&sev_cmd_mutex); rc = _sev_platform_init_locked(args); mutex_unlock(&sev_cmd_mutex); return rc; } EXPORT_SYMBOL_GPL(sev_platform_init); static int __sev_platform_shutdown_locked(int *error) { struct psp_device *psp = psp_master; struct sev_device *sev; int ret; if (!psp || !psp->sev_data) return 0; sev = psp->sev_data; if (sev->state == SEV_STATE_UNINIT) return 0; ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); if (ret) return ret; sev->state = SEV_STATE_UNINIT; dev_dbg(sev->dev, "SEV firmware shutdown\n"); return ret; } static int sev_get_platform_state(int *state, int *error) { struct sev_user_data_status data; int rc; rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); if (rc) return rc; *state = data.state; return rc; } static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) { int state, rc; if (!writable) return -EPERM; /* * The SEV spec requires that FACTORY_RESET must be issued in * UNINIT state. Before we go further lets check if any guest is * active. * * If FW is in WORKING state then deny the request otherwise issue * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. * */ rc = sev_get_platform_state(&state, &argp->error); if (rc) return rc; if (state == SEV_STATE_WORKING) return -EBUSY; if (state == SEV_STATE_INIT) { rc = __sev_platform_shutdown_locked(&argp->error); if (rc) return rc; } return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); } static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) { struct sev_user_data_status data; int ret; memset(&data, 0, sizeof(data)); ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); if (ret) return ret; if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) ret = -EFAULT; return ret; } static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; int rc; if (!writable) return -EPERM; if (sev->state == SEV_STATE_UNINIT) { rc = __sev_platform_init_locked(&argp->error); if (rc) return rc; } return __sev_do_cmd_locked(cmd, NULL, &argp->error); } static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_pek_csr input; struct sev_data_pek_csr data; void __user *input_address; void *blob = NULL; int ret; if (!writable) return -EPERM; if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; memset(&data, 0, sizeof(data)); /* userspace wants to query CSR length */ if (!input.address || !input.length) goto cmd; /* allocate a physically contiguous buffer to store the CSR blob */ input_address = (void __user *)input.address; if (input.length > SEV_FW_BLOB_MAX_SIZE) return -EFAULT; blob = kzalloc(input.length, GFP_KERNEL); if (!blob) return -ENOMEM; data.address = __psp_pa(blob); data.len = input.length; cmd: if (sev->state == SEV_STATE_UNINIT) { ret = __sev_platform_init_locked(&argp->error); if (ret) goto e_free_blob; } ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); /* If we query the CSR length, FW responded with expected data. */ input.length = data.len; if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { ret = -EFAULT; goto e_free_blob; } if (blob) { if (copy_to_user(input_address, blob, input.length)) ret = -EFAULT; } e_free_blob: kfree(blob); return ret; } void *psp_copy_user_blob(u64 uaddr, u32 len) { if (!uaddr || !len) return ERR_PTR(-EINVAL); /* verify that blob length does not exceed our limit */ if (len > SEV_FW_BLOB_MAX_SIZE) return ERR_PTR(-EINVAL); return memdup_user((void __user *)uaddr, len); } EXPORT_SYMBOL_GPL(psp_copy_user_blob); static int sev_get_api_version(void) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_status status; int error = 0, ret; ret = sev_platform_status(&status, &error); if (ret) { dev_err(sev->dev, "SEV: failed to get status. Error: %#x\n", error); return 1; } sev->api_major = status.api_major; sev->api_minor = status.api_minor; sev->build = status.build; sev->state = status.state; return 0; } static int sev_get_firmware(struct device *dev, const struct firmware **firmware) { char fw_name_specific[SEV_FW_NAME_SIZE]; char fw_name_subset[SEV_FW_NAME_SIZE]; snprintf(fw_name_specific, sizeof(fw_name_specific), "amd/amd_sev_fam%.2xh_model%.2xh.sbin", boot_cpu_data.x86, boot_cpu_data.x86_model); snprintf(fw_name_subset, sizeof(fw_name_subset), "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); /* Check for SEV FW for a particular model. * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h * * or * * Check for SEV FW common to a subset of models. * Ex. amd_sev_fam17h_model0xh.sbin for * Family 17h Model 00h -- Family 17h Model 0Fh * * or * * Fall-back to using generic name: sev.fw */ if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) return 0; return -ENOENT; } /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ static int sev_update_firmware(struct device *dev) { struct sev_data_download_firmware *data; const struct firmware *firmware; int ret, error, order; struct page *p; u64 data_size; if (!sev_version_greater_or_equal(0, 15)) { dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); return -1; } if (sev_get_firmware(dev, &firmware) == -ENOENT) { dev_dbg(dev, "No SEV firmware file present\n"); return -1; } /* * SEV FW expects the physical address given to it to be 32 * byte aligned. Memory allocated has structure placed at the * beginning followed by the firmware being passed to the SEV * FW. Allocate enough memory for data structure + alignment * padding + SEV FW. */ data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32); order = get_order(firmware->size + data_size); p = alloc_pages(GFP_KERNEL, order); if (!p) { ret = -1; goto fw_err; } /* * Copy firmware data to a kernel allocated contiguous * memory region. */ data = page_address(p); memcpy(page_address(p) + data_size, firmware->data, firmware->size); data->address = __psp_pa(page_address(p) + data_size); data->len = firmware->size; ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); /* * A quirk for fixing the committed TCB version, when upgrading from * earlier firmware version than 1.50. */ if (!ret && !sev_version_greater_or_equal(1, 50)) ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); if (ret) dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); else dev_info(dev, "SEV firmware update successful\n"); __free_pages(p, order); fw_err: release_firmware(firmware); return ret; } static int __sev_snp_shutdown_locked(int *error, bool panic) { struct sev_device *sev = psp_master->sev_data; struct sev_data_snp_shutdown_ex data; int ret; if (!sev->snp_initialized) return 0; memset(&data, 0, sizeof(data)); data.len = sizeof(data); data.iommu_snp_shutdown = 1; /* * If invoked during panic handling, local interrupts are disabled * and all CPUs are stopped, so wbinvd_on_all_cpus() can't be called. * In that case, a wbinvd() is done on remote CPUs via the NMI * callback, so only a local wbinvd() is needed here. */ if (!panic) wbinvd_on_all_cpus(); else wbinvd(); ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error); /* SHUTDOWN may require DF_FLUSH */ if (*error == SEV_RET_DFFLUSH_REQUIRED) { ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, NULL); if (ret) { dev_err(sev->dev, "SEV-SNP DF_FLUSH failed\n"); return ret; } /* reissue the shutdown command */ ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error); } if (ret) { dev_err(sev->dev, "SEV-SNP firmware shutdown failed\n"); return ret; } /* * SNP_SHUTDOWN_EX with IOMMU_SNP_SHUTDOWN set to 1 disables SNP * enforcement by the IOMMU and also transitions all pages * associated with the IOMMU to the Reclaim state. * Firmware was transitioning the IOMMU pages to Hypervisor state * before version 1.53. But, accounting for the number of assigned * 4kB pages in a 2M page was done incorrectly by not transitioning * to the Reclaim state. This resulted in RMP #PF when later accessing * the 2M page containing those pages during kexec boot. Hence, the * firmware now transitions these pages to Reclaim state and hypervisor * needs to transition these pages to shared state. SNP Firmware * version 1.53 and above are needed for kexec boot. */ ret = amd_iommu_snp_disable(); if (ret) { dev_err(sev->dev, "SNP IOMMU shutdown failed\n"); return ret; } sev->snp_initialized = false; dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n"); return ret; } static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_pek_cert_import input; struct sev_data_pek_cert_import data; void *pek_blob, *oca_blob; int ret; if (!writable) return -EPERM; if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; /* copy PEK certificate blobs from userspace */ pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); if (IS_ERR(pek_blob)) return PTR_ERR(pek_blob); data.reserved = 0; data.pek_cert_address = __psp_pa(pek_blob); data.pek_cert_len = input.pek_cert_len; /* copy PEK certificate blobs from userspace */ oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); if (IS_ERR(oca_blob)) { ret = PTR_ERR(oca_blob); goto e_free_pek; } data.oca_cert_address = __psp_pa(oca_blob); data.oca_cert_len = input.oca_cert_len; /* If platform is not in INIT state then transition it to INIT */ if (sev->state != SEV_STATE_INIT) { ret = __sev_platform_init_locked(&argp->error); if (ret) goto e_free_oca; } ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); e_free_oca: kfree(oca_blob); e_free_pek: kfree(pek_blob); return ret; } static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) { struct sev_user_data_get_id2 input; struct sev_data_get_id data; void __user *input_address; void *id_blob = NULL; int ret; /* SEV GET_ID is available from SEV API v0.16 and up */ if (!sev_version_greater_or_equal(0, 16)) return -ENOTSUPP; if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; input_address = (void __user *)input.address; if (input.address && input.length) { /* * The length of the ID shouldn't be assumed by software since * it may change in the future. The allocation size is limited * to 1 << (PAGE_SHIFT + MAX_PAGE_ORDER) by the page allocator. * If the allocation fails, simply return ENOMEM rather than * warning in the kernel log. */ id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); if (!id_blob) return -ENOMEM; data.address = __psp_pa(id_blob); data.len = input.length; } else { data.address = 0; data.len = 0; } ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); /* * Firmware will return the length of the ID value (either the minimum * required length or the actual length written), return it to the user. */ input.length = data.len; if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { ret = -EFAULT; goto e_free; } if (id_blob) { if (copy_to_user(input_address, id_blob, data.len)) { ret = -EFAULT; goto e_free; } } e_free: kfree(id_blob); return ret; } static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) { struct sev_data_get_id *data; u64 data_size, user_size; void *id_blob, *mem; int ret; /* SEV GET_ID available from SEV API v0.16 and up */ if (!sev_version_greater_or_equal(0, 16)) return -ENOTSUPP; /* SEV FW expects the buffer it fills with the ID to be * 8-byte aligned. Memory allocated should be enough to * hold data structure + alignment padding + memory * where SEV FW writes the ID. */ data_size = ALIGN(sizeof(struct sev_data_get_id), 8); user_size = sizeof(struct sev_user_data_get_id); mem = kzalloc(data_size + user_size, GFP_KERNEL); if (!mem) return -ENOMEM; data = mem; id_blob = mem + data_size; data->address = __psp_pa(id_blob); data->len = user_size; ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); if (!ret) { if (copy_to_user((void __user *)argp->data, id_blob, data->len)) ret = -EFAULT; } kfree(mem); return ret; } static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_pdh_cert_export input; void *pdh_blob = NULL, *cert_blob = NULL; struct sev_data_pdh_cert_export data; void __user *input_cert_chain_address; void __user *input_pdh_cert_address; int ret; /* If platform is not in INIT state then transition it to INIT. */ if (sev->state != SEV_STATE_INIT) { if (!writable) return -EPERM; ret = __sev_platform_init_locked(&argp->error); if (ret) return ret; } if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; memset(&data, 0, sizeof(data)); /* Userspace wants to query the certificate length. */ if (!input.pdh_cert_address || !input.pdh_cert_len || !input.cert_chain_address) goto cmd; input_pdh_cert_address = (void __user *)input.pdh_cert_address; input_cert_chain_address = (void __user *)input.cert_chain_address; /* Allocate a physically contiguous buffer to store the PDH blob. */ if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) return -EFAULT; /* Allocate a physically contiguous buffer to store the cert chain blob. */ if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) return -EFAULT; pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); if (!pdh_blob) return -ENOMEM; data.pdh_cert_address = __psp_pa(pdh_blob); data.pdh_cert_len = input.pdh_cert_len; cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); if (!cert_blob) { ret = -ENOMEM; goto e_free_pdh; } data.cert_chain_address = __psp_pa(cert_blob); data.cert_chain_len = input.cert_chain_len; cmd: ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); /* If we query the length, FW responded with expected data. */ input.cert_chain_len = data.cert_chain_len; input.pdh_cert_len = data.pdh_cert_len; if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { ret = -EFAULT; goto e_free_cert; } if (pdh_blob) { if (copy_to_user(input_pdh_cert_address, pdh_blob, input.pdh_cert_len)) { ret = -EFAULT; goto e_free_cert; } } if (cert_blob) { if (copy_to_user(input_cert_chain_address, cert_blob, input.cert_chain_len)) ret = -EFAULT; } e_free_cert: kfree(cert_blob); e_free_pdh: kfree(pdh_blob); return ret; } static int sev_ioctl_do_snp_platform_status(struct sev_issue_cmd *argp) { struct sev_device *sev = psp_master->sev_data; struct sev_data_snp_addr buf; struct page *status_page; void *data; int ret; if (!sev->snp_initialized || !argp->data) return -EINVAL; status_page = alloc_page(GFP_KERNEL_ACCOUNT); if (!status_page) return -ENOMEM; data = page_address(status_page); /* * Firmware expects status page to be in firmware-owned state, otherwise * it will report firmware error code INVALID_PAGE_STATE (0x1A). */ if (rmp_mark_pages_firmware(__pa(data), 1, true)) { ret = -EFAULT; goto cleanup; } buf.address = __psp_pa(data); ret = __sev_do_cmd_locked(SEV_CMD_SNP_PLATFORM_STATUS, &buf, &argp->error); /* * Status page will be transitioned to Reclaim state upon success, or * left in Firmware state in failure. Use snp_reclaim_pages() to * transition either case back to Hypervisor-owned state. */ if (snp_reclaim_pages(__pa(data), 1, true)) return -EFAULT; if (ret) goto cleanup; if (copy_to_user((void __user *)argp->data, data, sizeof(struct sev_user_data_snp_status))) ret = -EFAULT; cleanup: __free_pages(status_page, 0); return ret; } static int sev_ioctl_do_snp_commit(struct sev_issue_cmd *argp) { struct sev_device *sev = psp_master->sev_data; struct sev_data_snp_commit buf; if (!sev->snp_initialized) return -EINVAL; buf.len = sizeof(buf); return __sev_do_cmd_locked(SEV_CMD_SNP_COMMIT, &buf, &argp->error); } static int sev_ioctl_do_snp_set_config(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_snp_config config; if (!sev->snp_initialized || !argp->data) return -EINVAL; if (!writable) return -EPERM; if (copy_from_user(&config, (void __user *)argp->data, sizeof(config))) return -EFAULT; return __sev_do_cmd_locked(SEV_CMD_SNP_CONFIG, &config, &argp->error); } static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) { void __user *argp = (void __user *)arg; struct sev_issue_cmd input; int ret = -EFAULT; bool writable = file->f_mode & FMODE_WRITE; if (!psp_master || !psp_master->sev_data) return -ENODEV; if (ioctl != SEV_ISSUE_CMD) return -EINVAL; if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) return -EFAULT; if (input.cmd > SEV_MAX) return -EINVAL; mutex_lock(&sev_cmd_mutex); switch (input.cmd) { case SEV_FACTORY_RESET: ret = sev_ioctl_do_reset(&input, writable); break; case SEV_PLATFORM_STATUS: ret = sev_ioctl_do_platform_status(&input); break; case SEV_PEK_GEN: ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); break; case SEV_PDH_GEN: ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); break; case SEV_PEK_CSR: ret = sev_ioctl_do_pek_csr(&input, writable); break; case SEV_PEK_CERT_IMPORT: ret = sev_ioctl_do_pek_import(&input, writable); break; case SEV_PDH_CERT_EXPORT: ret = sev_ioctl_do_pdh_export(&input, writable); break; case SEV_GET_ID: pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); ret = sev_ioctl_do_get_id(&input); break; case SEV_GET_ID2: ret = sev_ioctl_do_get_id2(&input); break; case SNP_PLATFORM_STATUS: ret = sev_ioctl_do_snp_platform_status(&input); break; case SNP_COMMIT: ret = sev_ioctl_do_snp_commit(&input); break; case SNP_SET_CONFIG: ret = sev_ioctl_do_snp_set_config(&input, writable); break; default: ret = -EINVAL; goto out; } if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) ret = -EFAULT; out: mutex_unlock(&sev_cmd_mutex); return ret; } static const struct file_operations sev_fops = { .owner = THIS_MODULE, .unlocked_ioctl = sev_ioctl, }; int sev_platform_status(struct sev_user_data_status *data, int *error) { return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); } EXPORT_SYMBOL_GPL(sev_platform_status); int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) { return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); } EXPORT_SYMBOL_GPL(sev_guest_deactivate); int sev_guest_activate(struct sev_data_activate *data, int *error) { return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); } EXPORT_SYMBOL_GPL(sev_guest_activate); int sev_guest_decommission(struct sev_data_decommission *data, int *error) { return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); } EXPORT_SYMBOL_GPL(sev_guest_decommission); int sev_guest_df_flush(int *error) { return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); } EXPORT_SYMBOL_GPL(sev_guest_df_flush); static void sev_exit(struct kref *ref) { misc_deregister(&misc_dev->misc); kfree(misc_dev); misc_dev = NULL; } static int sev_misc_init(struct sev_device *sev) { struct device *dev = sev->dev; int ret; /* * SEV feature support can be detected on multiple devices but the SEV * FW commands must be issued on the master. During probe, we do not * know the master hence we create /dev/sev on the first device probe. * sev_do_cmd() finds the right master device to which to issue the * command to the firmware. */ if (!misc_dev) { struct miscdevice *misc; misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL); if (!misc_dev) return -ENOMEM; misc = &misc_dev->misc; misc->minor = MISC_DYNAMIC_MINOR; misc->name = DEVICE_NAME; misc->fops = &sev_fops; ret = misc_register(misc); if (ret) return ret; kref_init(&misc_dev->refcount); } else { kref_get(&misc_dev->refcount); } init_waitqueue_head(&sev->int_queue); sev->misc = misc_dev; dev_dbg(dev, "registered SEV device\n"); return 0; } int sev_dev_init(struct psp_device *psp) { struct device *dev = psp->dev; struct sev_device *sev; int ret = -ENOMEM; if (!boot_cpu_has(X86_FEATURE_SEV)) { dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); return 0; } sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); if (!sev) goto e_err; 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; sev->psp = psp; sev->io_regs = psp->io_regs; sev->vdata = (struct sev_vdata *)psp->vdata->sev; if (!sev->vdata) { ret = -ENODEV; dev_err(dev, "sev: missing driver data\n"); goto e_buf; } psp_set_sev_irq_handler(psp, sev_irq_handler, sev); ret = sev_misc_init(sev); if (ret) goto e_irq; dev_notice(dev, "sev enabled\n"); return 0; e_irq: psp_clear_sev_irq_handler(psp); e_buf: devm_free_pages(dev, (unsigned long)sev->cmd_buf); e_sev: devm_kfree(dev, sev); e_err: psp->sev_data = NULL; dev_notice(dev, "sev initialization failed\n"); return ret; } static void __sev_firmware_shutdown(struct sev_device *sev, bool panic) { int error; __sev_platform_shutdown_locked(NULL); if (sev_es_tmr) { /* * The TMR area was encrypted, flush it from the cache. * * If invoked during panic handling, local interrupts are * disabled and all CPUs are stopped, so wbinvd_on_all_cpus() * can't be used. In that case, wbinvd() is done on remote CPUs * via the NMI callback, and done for this CPU later during * SNP shutdown, so wbinvd_on_all_cpus() can be skipped. */ if (!panic) wbinvd_on_all_cpus(); __snp_free_firmware_pages(virt_to_page(sev_es_tmr), get_order(sev_es_tmr_size), true); sev_es_tmr = NULL; } if (sev_init_ex_buffer) { __snp_free_firmware_pages(virt_to_page(sev_init_ex_buffer), get_order(NV_LENGTH), true); sev_init_ex_buffer = NULL; } if (snp_range_list) { kfree(snp_range_list); snp_range_list = NULL; } __sev_snp_shutdown_locked(&error, panic); } static void sev_firmware_shutdown(struct sev_device *sev) { mutex_lock(&sev_cmd_mutex); __sev_firmware_shutdown(sev, false); mutex_unlock(&sev_cmd_mutex); } void sev_dev_destroy(struct psp_device *psp) { struct sev_device *sev = psp->sev_data; if (!sev) return; sev_firmware_shutdown(sev); if (sev->misc) kref_put(&misc_dev->refcount, sev_exit); psp_clear_sev_irq_handler(psp); } static int snp_shutdown_on_panic(struct notifier_block *nb, unsigned long reason, void *arg) { struct sev_device *sev = psp_master->sev_data; /* * If sev_cmd_mutex is already acquired, then it's likely * another PSP command is in flight and issuing a shutdown * would fail in unexpected ways. Rather than create even * more confusion during a panic, just bail out here. */ if (mutex_is_locked(&sev_cmd_mutex)) return NOTIFY_DONE; __sev_firmware_shutdown(sev, true); return NOTIFY_DONE; } static struct notifier_block snp_panic_notifier = { .notifier_call = snp_shutdown_on_panic, }; int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, void *data, int *error) { if (!filep || filep->f_op != &sev_fops) return -EBADF; return sev_do_cmd(cmd, data, error); } EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); void sev_pci_init(void) { struct sev_device *sev = psp_master->sev_data; struct sev_platform_init_args args = {0}; int rc; if (!sev) return; psp_timeout = psp_probe_timeout; if (sev_get_api_version()) goto err; if (sev_update_firmware(sev->dev) == 0) sev_get_api_version(); /* Initialize the platform */ args.probe = true; rc = sev_platform_init(&args); if (rc) dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n", args.error, rc); dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_initialized ? "-SNP" : "", sev->api_major, sev->api_minor, sev->build); atomic_notifier_chain_register(&panic_notifier_list, &snp_panic_notifier); return; err: psp_master->sev_data = NULL; } void sev_pci_exit(void) { struct sev_device *sev = psp_master->sev_data; if (!sev) return; sev_firmware_shutdown(sev); atomic_notifier_chain_unregister(&panic_notifier_list, &snp_panic_notifier); }