Before SNP VMs can be launched, the platform must be appropriately configured and initialized. Platform initialization is accomplished via the SNP_INIT command. Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx> --- drivers/crypto/ccp/sev-dev.c | 111 +++++++++++++++++++++++++++++++++-- drivers/crypto/ccp/sev-dev.h | 2 + include/linux/psp-sev.h | 16 +++++ 3 files changed, 124 insertions(+), 5 deletions(-) diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 0331d4cea7da..2203167dbc2e 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -591,6 +591,92 @@ static int sev_update_firmware(struct device *dev) return ret; } +static void snp_set_hsave_pa(void *arg) +{ + wrmsrl(MSR_VM_HSAVE_PA, 0); +} + +static int __sev_snp_init_locked(int *error) +{ + struct psp_device *psp = psp_master; + struct sev_device *sev; + int rc = 0; + + if (!psp || !psp->sev_data) + return -ENODEV; + + sev = psp->sev_data; + + if (sev->snp_inited) + return 0; + + /* SNP_INIT requires the MSR_VM_HSAVE_PA must be set to 0h across all cores. */ + on_each_cpu(snp_set_hsave_pa, NULL, 1); + + /* Prepare for first SEV guest launch after INIT */ + wbinvd_on_all_cpus(); + + /* Issue the SNP_INIT firmware command. */ + rc = __sev_do_cmd_locked(SEV_CMD_SNP_INIT, NULL, error); + if (rc) + return rc; + + sev->snp_inited = true; + dev_dbg(sev->dev, "SEV-SNP firmware initialized\n"); + + return rc; +} + +int sev_snp_init(int *error) +{ + int rc; + + if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP)) + return -ENODEV; + + mutex_lock(&sev_cmd_mutex); + rc = __sev_snp_init_locked(error); + mutex_unlock(&sev_cmd_mutex); + + return rc; +} +EXPORT_SYMBOL_GPL(sev_snp_init); + +static int __sev_snp_shutdown_locked(int *error) +{ + struct sev_device *sev = psp_master->sev_data; + int ret; + + if (!sev->snp_inited) + return 0; + + /* SHUTDOWN requires the DF_FLUSH */ + wbinvd_on_all_cpus(); + __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, NULL); + + ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN, NULL, error); + if (ret) { + dev_err(sev->dev, "SEV-SNP firmware shutdown failed\n"); + return ret; + } + + sev->snp_inited = false; + dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n"); + + return ret; +} + +static int sev_snp_shutdown(int *error) +{ + int rc; + + mutex_lock(&sev_cmd_mutex); + rc = __sev_snp_shutdown_locked(NULL); + mutex_unlock(&sev_cmd_mutex); + + return rc; +} + static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; @@ -1095,6 +1181,21 @@ void sev_pci_init(void) "SEV: TMR allocation failed, SEV-ES support unavailable\n"); } + /* + * If boot CPU supports the SNP, then let first attempt to initialize + * the SNP firmware. + */ + if (cpu_feature_enabled(X86_FEATURE_SEV_SNP)) { + rc = sev_snp_init(&error); + if (rc) { + /* + * If we failed to INIT SNP then don't abort the probe. + * Continue to initialize the legacy SEV firmware. + */ + dev_err(sev->dev, "SEV-SNP: failed to INIT error %#x\n", error); + } + } + /* Initialize the platform */ rc = sev_platform_init(&error); if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) { @@ -1109,13 +1210,11 @@ void sev_pci_init(void) rc = sev_platform_init(&error); } - if (rc) { + if (rc) dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error); - return; - } - dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, - sev->api_minor, sev->build); + dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_inited ? + "-SNP" : "", sev->api_major, sev->api_minor, sev->build); return; @@ -1138,4 +1237,6 @@ void sev_pci_exit(void) get_order(SEV_ES_TMR_SIZE)); sev_es_tmr = NULL; } + + sev_snp_shutdown(NULL); } diff --git a/drivers/crypto/ccp/sev-dev.h b/drivers/crypto/ccp/sev-dev.h index 666c21eb81ab..186ad20cbd24 100644 --- a/drivers/crypto/ccp/sev-dev.h +++ b/drivers/crypto/ccp/sev-dev.h @@ -52,6 +52,8 @@ struct sev_device { u8 build; void *cmd_buf; + + bool snp_inited; }; int sev_dev_init(struct psp_device *psp); diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h index c3755099ab55..1b53e8782250 100644 --- a/include/linux/psp-sev.h +++ b/include/linux/psp-sev.h @@ -748,6 +748,20 @@ struct sev_data_snp_init_ex { */ int sev_platform_init(int *error); +/** + * sev_snp_init - perform SEV SNP_INIT command + * + * @error: SEV command return code + * + * Returns: + * 0 if the SEV successfully processed the command + * -%ENODEV if the SEV device is not available + * -%ENOTSUPP if the SEV does not support SEV + * -%ETIMEDOUT if the SEV command timed out + * -%EIO if the SEV returned a non-zero return code + */ +int sev_snp_init(int *error); + /** * sev_platform_status - perform SEV PLATFORM_STATUS command * @@ -855,6 +869,8 @@ sev_platform_status(struct sev_user_data_status *status, int *error) { return -E static inline int sev_platform_init(int *error) { return -ENODEV; } +static inline int sev_snp_init(int *error) { return -ENODEV; } + static inline int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) { return -ENODEV; } -- 2.17.1