On Fri, Oct 29, 2021 at 8:45 AM Tom Lendacky <thomas.lendacky@xxxxxxx> wrote: > > On 10/28/21 12:57 PM, Peter Gonda 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. > > IIUC, it looks as though the file has to exist before the very first use, > otherwise the initialization will fail. Did you consider checking for the > presence of the file first and, if not there, just using a memory area of > all f's (as documented in the SEV API)? Then on successful INIT, the > memory would be written and the file created. Thats a great idea. I'll add that functionality. > > Either way, probably worth adding to the commit message. And if you stay > with having to pre-allocate the file, it's worth adding to the SEV > documentation what is required to be done to initialize the file. > > Although, INIT_EX is probably worth adding to the SEV documentation in > general. Is this (https://www.kernel.org/doc/Documentation/virt/kvm/amd-memory-encryption.rst) the documentation you were referring too? If so I can add another patch before this one to document INIT, then add the INIT_EX documentation here. Or were you thinking something else? > > > > > 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) > > Just me, but I think '32 * 1024' would be a bit clearer. SGTM and more consistent with SEV_ES_TMR_SIZE. > > > +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); > > Maybe move this to just under the SEV_CMD_INIT: case statement? > > > 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); > > Add a blank line here. > > > + 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); > > + } > > Add a blank line here. > > > + 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"); > > Add a blank line here. Added all these blank lines. > > > + 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, > > maybe say INIT(_EX)? Done. > > > + * PLATFORM_RESET, PEK_GEN, PEK_CERT_IMPORT, and > > + * PDH_GEN do. > > Does SHUTDOWN modify the SPI/NV area? Otherwise a separate comment about > why it is included below. Double checked the FW doc looks like it does not. Richard can you confirm? If it doesn't I'll remove this case. > > > + */ > > + 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); > > You already have error messages in the sev_write_nv_memory() function, > this one probably isn't needed. Removed. > > > +} > > + > > 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; > > Inadvertant deletion? Oops only testing with SEV guests. Will test with ES too. Fixed. > > > data.tmr_address = tmr_pa; > > data.tmr_len = SEV_ES_TMR_SIZE; > > } > > Add a blank line here. > > > + 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; > > This seems a bit much in the declaration. How about moving the assignment > down to just before the first call? Done. > > > + > > + 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"); > > Maybe dev_notice() instead of dev_err()? Done., > > > + 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"); > > Not sure this is a necessary change... but, if you don't want this as a > dev_dbg() then it should be a dev_info(), because it is not an error. Oops this was my debugging. Reverted. > > > > > 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( > > Shouldn't this be a dev_err(), since you are erroring out? > > > + sev->dev, > > Move this up to the previous line, i.e.: dev_err(sev->dev, > > > + "SEV: INIT_EX NV storage allocation failed, INIT-EX support unavailable\n"); > > Since you're erroring out, probably enough to just have the first part of > that message. But if not: > > s/INIT-EX/INIT_EX/ Fixed this log line. > > Thanks, > Tom > > > + 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 > > > > /** > >
