@@ -85,6 +85,12 @@ guests, such as launching, running, snapshotting, migrating and decommissioning.
The KVM_SEV_INIT command is used by the hypervisor to initialize the SEV platform
context. In a typical workflow, this command should be the first command issued.
+The firmware can be initialized either by using its own non-volatile storage or
+the OS can manage the NV storage for the firmware using the module parameter
+``init_ex_path``. The file specified by ``init_ex_path`` must exist. To create
+a new NV storage file allocate the file with 32KB bytes of 0xFF as required by
+the SEV spec.
+
Returns: 0 on success, -negative on error
2. KVM_SEV_LAUNCH_START
@@ -22,6 +22,7 @@
#include <linux/firmware.h>
#include <linux/gfp.h>
#include <linux/cpufeature.h>
+#include <linux/fs.h>
#include <asm/smp.h>
@@ -43,6 +44,10 @@ 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");
@@ -62,6 +67,14 @@ static int psp_timeout;
#define SEV_ES_TMR_SIZE (1024 * 1024)
static void *sev_es_tmr;
+/* 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;
+
static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
{
struct sev_device *sev = psp_master->sev_data;
@@ -111,6 +124,7 @@ 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_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);
@@ -156,6 +170,102 @@ static void *sev_fw_alloc(unsigned long len)
return page_address(page);
}
+static int sev_read_init_ex_file(void)
+{
+ struct sev_device *sev = psp_master->sev_data;
+ struct file *fp;
+ ssize_t nread;
+ loff_t pos = 0;
+
+ lockdep_assert_held(sev_cmd_mutex);
+
+ if (!sev_init_ex_buffer)
+ return -EOPNOTSUPP;
+
+ fp = filp_open(init_ex_path, O_RDONLY, 0);
+ if (IS_ERR(fp)) {
+ int ret = PTR_ERR(fp);
+
+ 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, &pos);
+ if (nread != NV_LENGTH) {
+ dev_err(sev->dev,
+ "SEV: failed to read %u bytes to non volatile memory area, ret %ld\n",
+ NV_LENGTH, nread);
+ return -EIO;
+ }
+
+ dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
+ filp_close(fp, NULL);
+
+ return 0;
+}
+
+static void 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;
+
+ fp = filp_open(init_ex_path, O_CREAT | O_WRONLY, 0600);
+ if (IS_ERR(fp)) {
+ dev_err(sev->dev,
+ "SEV: could not open file for write, error %d\n",
+ PTR_ERR(fp));
+ return;
+ }
+
+ 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;
+ }
+
+ dev_dbg(sev->dev, "SEV: write successful to NV file\n");
+}
+
+static void sev_write_init_ex_file_if_required(int cmd_id)
+{
+ lockdep_assert_held(sev_cmd_mutex);
+
+ if (!sev_init_ex_buffer)
+ return;
+
+ /*
+ * 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;
+ };
+
+ sev_write_init_ex_file();
+}
+
static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
{
struct psp_device *psp = psp_master;
@@ -225,6 +335,8 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
cmd, reg & PSP_CMDRESP_ERR_MASK);
ret = -EIO;
+ } else {
+ sev_write_init_ex_file_if_required(cmd);
}
print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
@@ -251,37 +363,71 @@ static int sev_do_cmd(int cmd, void *data, int *psp_ret)
return rc;
}
-static int __sev_platform_init_locked(int *error)
+static int __sev_init_locked(int *error)
{
- struct psp_device *psp = psp_master;
struct sev_data_init data;
- struct sev_device *sev;
- int psp_ret, rc = 0;
- if (!psp || !psp->sev_data)
- return -ENODEV;
+ 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);
- sev = psp->sev_data;
+ data.flags |= SEV_INIT_FLAGS_SEV_ES;
+ data.tmr_len = SEV_ES_TMR_SIZE;
+ }
- if (sev->state == SEV_STATE_INIT)
- return 0;
+ return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
+}
+
+static int __sev_init_ex_locked(int *error)
+{
+ struct sev_data_init_ex data;
+ int ret;
memset(&data, 0, sizeof(data));
- if (sev_es_tmr) {
- u64 tmr_pa;
+ data.length = sizeof(data);
+ data.nv_address = __psp_pa(sev_init_ex_buffer);
+ data.nv_len = NV_LENGTH;
+ ret = sev_read_init_ex_file();
+ if (ret)
+ return ret;
+
+ if (sev_es_tmr) {
/*
* Do not include the encryption mask on the physical
* address of the TMR (firmware should clear it anyway).
*/
- tmr_pa = __pa(sev_es_tmr);
+ data.tmr_address = __pa(sev_es_tmr);
data.flags |= SEV_INIT_FLAGS_SEV_ES;
- data.tmr_address = tmr_pa;
data.tmr_len = SEV_ES_TMR_SIZE;
}
- rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, &psp_ret);
+ return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
+}
+
+static int __sev_platform_init_locked(int *error)
+{
+ struct psp_device *psp = psp_master;
+ struct sev_device *sev;
+ int rc, psp_ret;
+ int (*init_function)(int *error);
+
+ if (!psp || !psp->sev_data)
+ return -ENODEV;
+
+ sev = psp->sev_data;
+
+ if (sev->state == SEV_STATE_INIT)
+ return 0;
+
+ init_function = sev_init_ex_buffer ? __sev_init_ex_locked :
+ __sev_init_locked;
+ rc = init_function(&psp_ret);
if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
/*
* Initialization command returned an integrity check failure
@@ -291,7 +437,7 @@ static int __sev_platform_init_locked(int *error)
* with a reset state.
*/
dev_dbg(sev->dev, "SEV: retrying INIT command");
- rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, &psp_ret);
+ rc = init_function(&psp_ret);
}
if (error)
*error = psp_ret;
@@ -1066,6 +1212,12 @@ static void sev_firmware_shutdown(struct sev_device *sev)
get_order(SEV_ES_TMR_SIZE));
sev_es_tmr = NULL;
}
+
+ if (sev_init_ex_buffer) {
+ free_pages((unsigned long)sev_init_ex_buffer,
+ get_order(NV_LENGTH));
+ sev_init_ex_buffer = NULL;
+ }
}
void sev_dev_destroy(struct psp_device *psp)
@@ -1111,6 +1263,18 @@ void sev_pci_init(void)
sev_update_firmware(sev->dev) == 0)
sev_get_api_version();
+ /* If an init_ex_path is provided rely on INIT_EX for PSP initialization
+ * instead of INIT.
+ */
+ if (init_ex_path) {
+ sev_init_ex_buffer = sev_fw_alloc(NV_LENGTH);
+ if (!sev_init_ex_buffer) {
+ dev_err(sev->dev,
+ "SEV: INIT_EX NV memory allocation failed\n");
+ goto err;
+ }
+ }
+
/* Obtain the TMR memory area for SEV-ES use */
sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
if (!sev_es_tmr)
@@ -52,6 +52,7 @@ enum sev_cmd {
SEV_CMD_DF_FLUSH = 0x00A,
SEV_CMD_DOWNLOAD_FIRMWARE = 0x00B,
SEV_CMD_GET_ID = 0x00C,
+ SEV_CMD_INIT_EX = 0x00D,
/* Guest commands */
SEV_CMD_DECOMMISSION = 0x020,
@@ -102,6 +103,26 @@ struct sev_data_init {
u32 tmr_len; /* In */
} __packed;
+/**
+ * struct sev_data_init_ex - INIT_EX command parameters
+ *
+ * @length: len of the command buffer read by the PSP
+ * @flags: processing flags
+ * @tmr_address: system physical address used for SEV-ES
+ * @tmr_len: len of tmr_address
+ * @nv_address: system physical address used for PSP NV storage
+ * @nv_len: len of nv_address
+ */
+struct sev_data_init_ex {
+ u32 length; /* In */
+ u32 flags; /* In */
+ u64 tmr_address; /* In */
+ u32 tmr_len; /* In */
+ u32 reserved; /* In */
+ u64 nv_address; /* In/Out */
+ u32 nv_len; /* In */
+} __packed;
+
#define SEV_INIT_FLAGS_SEV_ES 0x01
/**