On Thu, Oct 28, 2021 at 10:58 AM Peter Gonda <pgonda@xxxxxxxxxx> wrote: > > From: David Rientjes <rientjes@xxxxxxxxxx> > > Add new module parameter to allow users to use SEV_INIT_EX instead of > SEV_INIT. This helps users who lock their SPI bus to use the PSP for SEV > functionality. The 'init_ex_path' parameter defaults to NULL which means > the kernel will use SEV_INIT, if a path is specified SEV_INIT_EX will be > used with the data found at the path. On certain PSP commands this > file is written to as the PSP updates the NV memory region. Depending on > file system initialization this file open may fail during module init > but the CCP driver for SEV already has sufficient retries for platform > initialization. During normal operation of PSP system and SEV commands > if the PSP has not been initialized it is at run time. > > Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> > Co-developed-by: Peter Gonda <pgonda@xxxxxxxxxx> > Signed-off-by: Peter Gonda <pgonda@xxxxxxxxxx> > Cc: Tom Lendacky <thomas.lendacky@xxxxxxx> > Cc: Brijesh Singh <brijesh.singh@xxxxxxx> > Cc: Marc Orr <marcorr@xxxxxxxxxx> > Cc: Joerg Roedel <jroedel@xxxxxxx> > Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Cc: John Allen <john.allen@xxxxxxx> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> ( > Cc: linux-crypto@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > --- > drivers/crypto/ccp/sev-dev.c | 186 ++++++++++++++++++++++++++++++++--- > include/linux/psp-sev.h | 21 ++++ > 2 files changed, 192 insertions(+), 15 deletions(-) > > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c > index b568ae734857..c8718b4cbc93 100644 > --- a/drivers/crypto/ccp/sev-dev.c > +++ b/drivers/crypto/ccp/sev-dev.c > @@ -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, 0660); > +MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); > + > 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 */ > @@ -58,6 +63,14 @@ 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 << 10) > +static void *sev_init_ex_nv_address; > + > static inline bool sev_version_greater_or_equal(u8 maj, u8 min) > { > struct sev_device *sev = psp_master->sev_data; > @@ -135,6 +148,7 @@ static int sev_cmd_buffer_len(int cmd) > 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_INIT_EX: return sizeof(struct sev_data_init_ex); > default: return 0; > } > > @@ -156,6 +170,89 @@ static void *sev_fw_alloc(unsigned long len) > return page_address(page); > } > > +static int sev_read_nv_memory(void) > +{ > + struct file *fp; > + ssize_t nread; > + > + if (!sev_init_ex_nv_address) > + return -EOPNOTSUPP; > + > + fp = filp_open(init_ex_path, O_RDONLY, 0); > + if (IS_ERR(fp)) { > + dev_err(psp_master->dev, "sev could not open file for read\n"); > + return PTR_ERR(fp); > + } > + > + nread = kernel_read(fp, sev_init_ex_nv_address, NV_LENGTH, 0); > + dev_dbg(psp_master->dev, "sev NV read %d bytes\n", nread); > + filp_close(fp, NULL); > + return 0; > +} > + > +static int sev_write_nv_memory(void) > +{ > + struct sev_device *sev = psp_master->sev_data; > + struct file *fp; > + loff_t offset = 0; > + int ret; > + > + if (!sev_init_ex_nv_address) > + return -EOPNOTSUPP; > + > + fp = filp_open(init_ex_path, O_CREAT | O_WRONLY, 0600); > + if (IS_ERR(fp)) { > + dev_err(sev->dev, "sev NV data could not be created\n"); > + return PTR_ERR(fp); > + } > + ret = kernel_write(fp, sev_init_ex_nv_address, NV_LENGTH, &offset); > + vfs_fsync(fp, 0); > + filp_close(fp, NULL); > + > + if (ret != NV_LENGTH) { > + dev_err(sev->dev, > + "failed to write %d bytes to non volatile memory area, ret=%lu\n", > + NV_LENGTH, ret); > + if (ret >= 0) > + return -EIO; > + return ret; > + } > + > + dev_dbg(sev->dev, "wrote to non volatile memory area\n"); > + return 0; > +} > + > +static void sev_write_nv_memory_if_required(int cmd_id) > +{ > + struct sev_device *sev = psp_master->sev_data; > + int ret; > + > + if (!sev_init_ex_nv_address) > + return; > + > + /* > + * Only a few platform commands modify the SPI/NV area, > + * but none of the non-platform commands do. Only INIT, > + * 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: > + case SEV_CMD_SHUTDOWN: > + break; > + default: > + return; > + }; > + > + ret = sev_write_nv_memory(); > + if (ret) > + dev_err(sev->dev, "sev NV write failed %d\n", ret); > +} > + > static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) > { > struct psp_device *psp = psp_master; > @@ -225,6 +322,8 @@ 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_nv_memory_if_required(cmd); > } > > print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, > @@ -251,22 +350,42 @@ 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 rc = 0; > > - if (!psp || !psp->sev_data) > - return -ENODEV; > + memset(&data, 0, sizeof(data)); > + if (sev_es_tmr) { > + u64 tmr_pa; > > - sev = psp->sev_data; > + /* > + * Do not include the encryption mask on the physical > + * address of the TMR (firmware should clear it anyway). > + */ > + tmr_pa = __pa(sev_es_tmr); > > - if (sev->state == SEV_STATE_INIT) > - return 0; > + data.flags |= SEV_INIT_FLAGS_SEV_ES; > + data.tmr_address = tmr_pa; > + 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; > + int ret; > > memset(&data, 0, sizeof(data)); > + data.length = sizeof(data); > + data.nv_address = __psp_pa(sev_init_ex_nv_address); > + data.nv_len = NV_LENGTH; > + > + ret = sev_read_nv_memory(); > + if (ret) > + return ret; > + > if (sev_es_tmr) { > u64 tmr_pa; > > @@ -276,12 +395,30 @@ static int __sev_platform_init_locked(int *error) > */ > tmr_pa = __pa(sev_es_tmr); > > - data.flags |= SEV_INIT_FLAGS_SEV_ES; > data.tmr_address = tmr_pa; > data.tmr_len = SEV_ES_TMR_SIZE; > } > + 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; > + int (*init_function)(int *error) = sev_init_ex_nv_address ? > + __sev_init_ex_locked : > + __sev_init_locked; > + > + if (!psp || !psp->sev_data) > + return -ENODEV; > + > + sev = psp->sev_data; > > - rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); > + if (sev->state == SEV_STATE_INIT) > + return 0; > + > + rc = init_function(error); > if (rc && *error == SEV_RET_SECURE_DATA_INVALID) { > /* > * INIT command returned an integrity check failure > @@ -290,8 +427,8 @@ static int __sev_platform_init_locked(int *error) > * failed and persistent state has been erased. > * Retrying INIT command here should succeed. > */ > - dev_dbg(sev->dev, "SEV: retrying INIT command"); > - rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); > + dev_err(sev->dev, "SEV: retrying INIT command"); > + rc = init_function(error); > } > > if (rc) > @@ -307,7 +444,7 @@ static int __sev_platform_init_locked(int *error) > > dev_dbg(sev->dev, "SEV firmware initialized\n"); > > - return rc; > + return 0; > } > > int sev_platform_init(int *error) > @@ -987,7 +1124,7 @@ static int sev_misc_init(struct sev_device *sev) > > init_waitqueue_head(&sev->int_queue); > sev->misc = misc_dev; > - dev_dbg(dev, "registered SEV device\n"); > + dev_err(dev, "registered SEV device\n"); > > return 0; > } > @@ -1061,6 +1198,12 @@ static void sev_firmware_shutdown(struct sev_device *sev) > get_order(SEV_ES_TMR_SIZE)); > sev_es_tmr = NULL; > } > + > + if (sev_init_ex_nv_address) { > + free_pages((unsigned long)sev_init_ex_nv_address, > + get_order(NV_LENGTH)); > + sev_init_ex_nv_address = NULL; > + } > } > > void sev_dev_destroy(struct psp_device *psp) > @@ -1105,6 +1248,19 @@ 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_nv_address = sev_fw_alloc(NV_LENGTH); > + if (!sev_init_ex_nv_address) { > + dev_warn( > + sev->dev, > + "SEV: INIT_EX NV storage allocation failed, INIT-EX support unavailable\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) > diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h > index d48a7192e881..1595088c428b 100644 > --- a/include/linux/psp-sev.h > +++ b/include/linux/psp-sev.h > @@ -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 > > /** > -- > 2.33.1.1089.g2158813163f-goog > Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx>