Message-ID: <91984541-504a-f029-47ca-bde538e07436@amd.com>
Date: Mon, 4 Nov 2024 11:06:12 -0600
From: Tom Lendacky <thomas.lendacky@....com>
To: Dionna Glaze <dionnaglaze@...gle.com>, linux-kernel@...r.kernel.org,
 x86@...nel.org, John Allen <john.allen@....com>,
 Herbert Xu <herbert@...dor.apana.org.au>,
 "David S. Miller" <davem@...emloft.net>, Ashish Kalra <ashish.kalra@....com>
Cc: Sean Christopherson <seanjc@...gle.com>,
 Paolo Bonzini <pbonzini@...hat.com>, Thomas Gleixner <tglx@...utronix.de>,
 Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
 Dave Hansen <dave.hansen@...ux.intel.com>,
 Michael Roth <michael.roth@....com>, Luis Chamberlain <mcgrof@...nel.org>,
 Russ Weight <russ.weight@...ux.dev>, Danilo Krummrich <dakr@...hat.com>,
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
 "Rafael J. Wysocki" <rafael@...nel.org>,
 Tianfei zhang <tianfei.zhang@...el.com>, Alexey Kardashevskiy <aik@....com>,
 linux-crypto@...r.kernel.org
Subject: Re: [PATCH v3 3/4] crypto: ccp: Add SNP firmware hotload support

On 11/1/24 19:08, Dionna Glaze wrote:
> uapi changes: The status values added are defined in AMD's SEV-SNP API
> documentation as new error modes for the DOWNLOAD_FIRMWARE_EX command.
> 
> On init, the ccp device will make /sys/class/firmware/amd/loading etc
> firmware upload API attributes available to late-load a SEV-SNP firmware
> binary.
> 
> The firmware upload api errors reported are actionable in the following
> ways:
> * FW_UPLOAD_ERR_HW_ERROR: the machine is in an unstable state and must
>   be reset.
> * FW_UPLOAD_ERR_RW_ERROR: the firmware update went bad but can be
>   recovered by hotloading the previous firmware version.
>   Also used in the case that the kernel used the API wrong (bug).
> * FW_UPLOAD_ERR_FW_INVALID: user error with the data provided, but no
>   instability is expected and no recovery actions are needed.
> * FW_UPLOAD_ERR_BUSY: upload attempted at a bad time either due to
>   overload or the machine is in the wrong platform state.
> 
> snp_asid_to_gctx_page_map:
> Compliance with SEV-SNP API section 3.3 Firmware Updates and 4.1.1
> Live Update: before a firmware is committed, all active GCTX pages
> should be updated with SNP_GUEST_STATUS to ensure their data structure
> remains consistent for the new firmware version.
> There can only be cpuid_edx(0x8000001f)-1 many SEV-SNP asids in use at
> one time, so this map associates asid to gctx in order to track which
> addresses are active gctx pages that need updating. When an asid and
> gctx page are decommissioned, the page is removed from tracking for
> update-purposes.
> Given that GCTX page creation and binding through the SNP_ACTIVATE
> command are separate, the creation operation also tracks pages that are
> yet to be bound to an asid.
> 
> synthetic_restore_required:
> Instead of tracking the status of whether an individual GCTX is safe for
> use in a firmware command, force all following commands to fail with an
> error that is indicative of needing a firmware rollback.
> 
> According to SEV-SNP API section 3.3 Firmware Updates, the
> DOWNLOAD_FIRMWARE_EX command is usable when the SNP firmware is in
> either UNINIT or INIT states, but SEV-legacy firmware must be in the
> UNINIT state. A sev_platform_init call when only SEV-SNP VMs are
> expected should set supports_download_firmware_ex to delay legacy
> initialization actions.
> The firmware can only be hotloaded for SEV VMs when legacy
> initialization has not happened.
> 
> To test:
> 1. Build the kernel enabling SEV-SNP as normal and add CONFIG_FW_UPLOAD=y.
> 2. Add the following to your kernel_cmdline: ccp.psp_init_on_probe=0.
> 3.Get an AMD SEV-SNP firmware sbin appropriate to your Epyc chip model at
> https://www.amd.com/en/developer/sev.html and extract to get a .sbin
> file.
> 4. Run the following with your sbinfile in FW:
> 
> echo 1 > /sys/class/firmware/snp_dlfw_ex/loading
> cat "${FW?}" > /sys/class/firmware/snp_dlfw_ex/data
> echo 0 > /sys/class/firmware/snp_dlfw_ex/loading
> 
> 5. Verify the firmware update message in dmesg.
> 
> CC: Sean Christopherson <seanjc@...gle.com>
> CC: Paolo Bonzini <pbonzini@...hat.com>
> CC: Thomas Gleixner <tglx@...utronix.de>
> CC: Ingo Molnar <mingo@...hat.com>
> CC: Borislav Petkov <bp@...en8.de>
> CC: Dave Hansen <dave.hansen@...ux.intel.com>
> CC: Ashish Kalra <ashish.kalra@....com>
> CC: Tom Lendacky <thomas.lendacky@....com>
> CC: John Allen <john.allen@....com>
> CC: Herbert Xu <herbert@...dor.apana.org.au>
> CC: "David S. Miller" <davem@...emloft.net>
> CC: Michael Roth <michael.roth@....com>
> CC: Luis Chamberlain <mcgrof@...nel.org>
> CC: Russ Weight <russ.weight@...ux.dev>
> CC: Danilo Krummrich <dakr@...hat.com>
> CC: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
> CC: "Rafael J. Wysocki" <rafael@...nel.org>
> CC: Tianfei zhang <tianfei.zhang@...el.com>
> CC: Alexey Kardashevskiy <aik@....com>
> 
> Co-developed-by: Ashish Kalra <ashish.kalra@....com>
> Signed-off-by: Ashish Kalra <ashish.kalra@....com>
> Tested-by: Ashish Kalra <ashish.kalra@....com>
> Signed-off-by: Dionna Glaze <dionnaglaze@...gle.com>
> ---
>  drivers/crypto/ccp/Kconfig   |   2 +
>  drivers/crypto/ccp/sev-dev.c | 399 ++++++++++++++++++++++++++++++++++-
>  drivers/crypto/ccp/sev-dev.h |  14 ++
>  include/linux/psp-sev.h      |  29 +++
>  include/uapi/linux/psp-sev.h |   5 +
>  5 files changed, 441 insertions(+), 8 deletions(-)

This is a big patch. Can you split this up into smaller patches? At a
minimum, one patch that adds the context tracking and one that adds the
firmware support.

Also, can the guest context page tracking and new firmware related
functions be placed in a new file, sev-fw.c or similar, that is
conditionally built based on CONFIG_FW_UPLOAD. Then a header file can be
used to provide the different implementations of the new functions
removing the #ifdefs from the code.

Thanks,
Tom

> 
> diff --git a/drivers/crypto/ccp/Kconfig b/drivers/crypto/ccp/Kconfig
> index f394e45e11ab4..cd9b667640e7c 100644
> --- a/drivers/crypto/ccp/Kconfig
> +++ b/drivers/crypto/ccp/Kconfig
> @@ -39,6 +39,8 @@ config CRYPTO_DEV_SP_PSP
>  	bool "Platform Security Processor (PSP) device"
>  	default y
>  	depends on CRYPTO_DEV_CCP_DD && X86_64 && AMD_IOMMU
> +	select FW_LOADER
> +        select FW_UPLOAD
>  	help
>  	 Provide support for the AMD Platform Security Processor (PSP).
>  	 The PSP is a dedicated processor that provides support for key
> diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
> index 9810edbb272d2..1da183e8a9ebc 100644
> --- a/drivers/crypto/ccp/sev-dev.c
> +++ b/drivers/crypto/ccp/sev-dev.c
> @@ -223,6 +223,7 @@ static int sev_cmd_buffer_len(int cmd)
>  	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);
> +	case SEV_CMD_SNP_DOWNLOAD_FIRMWARE_EX:	return sizeof(struct sev_data_download_firmware_ex);
>  	default:				return 0;
>  	}
>  
> @@ -829,6 +830,7 @@ static int snp_reclaim_cmd_buf(int cmd, void *cmd_buf)
>  	return 0;
>  }
>  
> +static void snp_cmd_bookkeeping_locked(int cmd, struct sev_device *sev, void *data);
>  static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
>  {
>  	struct cmd_buf_desc desc_list[CMD_BUF_DESC_MAX] = {0};
> @@ -852,6 +854,15 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
>  	if (WARN_ON_ONCE(!data != !buf_len))
>  		return -EINVAL;
>  
> +	/* The firmware does not coordinate all GCTX page updates. Force an
> +	 * error to ensure that no new VM can be started and no active VM makes
> +	 * progress on guest requests until the firmware is rolled back.
> +	 */
> +	if (sev->synthetic_restore_required) {
> +		*psp_ret = SEV_RET_RESTORE_REQUIRED;
> +		return -EBUSY;
> +	}
> +
>  	/*
>  	 * 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
> @@ -982,6 +993,9 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
>  	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
>  			     buf_len, false);
>  
> +	if (!ret)
> +		snp_cmd_bookkeeping_locked(cmd, sev, data);
> +
>  	return ret;
>  }
>  
> @@ -1082,6 +1096,7 @@ static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
>  	return 0;
>  }
>  
> +static int sev_snp_platform_init_firmware_upload(struct sev_device *sev);
>  static int __sev_snp_init_locked(int *error)
>  {
>  	struct psp_device *psp = psp_master;
> @@ -1179,6 +1194,8 @@ static int __sev_snp_init_locked(int *error)
>  
>  	sev_es_tmr_size = SNP_TMR_SIZE;
>  
> +	rc = sev_snp_platform_init_firmware_upload(sev);
> +
>  	return rc;
>  }
>  
> @@ -1326,6 +1343,13 @@ static int _sev_platform_init_locked(struct sev_platform_init_args *args)
>  	if (args->probe && !psp_init_on_probe)
>  		return 0;
>  
> +	/*
> +	 * Defer legacy SEV/SEV-ES support if legacy VMs are not being launched
> +	 * and module psp_init_on_probe parameter is false.
> +	 */
> +	if (args->supports_download_firmware_ex && !psp_init_on_probe)
> +		return 0;
> +
>  	return __sev_platform_init_locked(&args->error);
>  }
>  
> @@ -1592,14 +1616,8 @@ static int sev_update_firmware(struct device *dev)
>  		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);
> +	data_size = ALIGN(sizeof(struct sev_data_download_firmware),
> +			  SEV_FW_ALIGNMENT);
>  
>  	order = get_order(firmware->size + data_size);
>  	p = alloc_pages(GFP_KERNEL, order);
> @@ -2224,6 +2242,367 @@ static int sev_misc_init(struct sev_device *sev)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_FW_UPLOAD
> +
> +static enum fw_upload_err snp_dlfw_ex_prepare(struct fw_upload *fw_upload,
> +					      const u8 *data, u32 size)
> +{
> +	return FW_UPLOAD_ERR_NONE;
> +}
> +
> +static enum fw_upload_err snp_dlfw_ex_poll_complete(struct fw_upload *fw_upload)
> +{
> +	return FW_UPLOAD_ERR_NONE;
> +}
> +
> +/*
> + * This may be called asynchronously with an on-going update.  All other
> + * functions are called sequentially in a single thread. To avoid contention on
> + * register accesses, only update the cancel_request flag. Other functions will
> + * check this flag and handle the cancel request synchronously.
> + */
> +static void snp_dlfw_ex_cancel(struct fw_upload *fw_upload)
> +{
> +	struct sev_device *sev = psp_master->sev_data;
> +
> +	mutex_lock(&sev->fw_lock);
> +	sev->fw_cancel = true;
> +	mutex_unlock(&sev->fw_lock);
> +}
> +
> +static enum fw_upload_err snp_dlfw_ex_err_translate(struct sev_device *sev, int psp_ret)
> +{
> +	dev_dbg(sev->dev, "Failed to update SEV firmware: %#x\n", psp_ret);
> +	/*
> +	 * Operation error:
> +	 *   HW_ERROR: Critical error. Machine needs repairs now.
> +	 *   RW_ERROR: Severe error. Roll back to the prior version to recover.
> +	 * User error:
> +	 *   FW_INVALID: Bad input for this interface.
> +	 *   BUSY: Wrong machine state to run download_firmware_ex.
> +	 */
> +	switch (psp_ret) {
> +	case SEV_RET_RESTORE_REQUIRED:
> +		dev_warn(sev->dev, "Firmware updated but unusable\n");
> +		dev_warn(sev->dev, "Need to do manual firmware rollback!!!\n");
> +		return FW_UPLOAD_ERR_RW_ERROR;
> +	case SEV_RET_SHUTDOWN_REQUIRED:
> +		/* No state changes made. Not a hardware error. */
> +		dev_warn(sev->dev, "Firmware image cannot be live updated\n");
> +		return FW_UPLOAD_ERR_FW_INVALID;
> +	case SEV_RET_BAD_VERSION:
> +		/* No state changes made. Not a hardware error. */
> +		dev_warn(sev->dev, "Firmware image is not well formed\n");
> +		return FW_UPLOAD_ERR_FW_INVALID;
> +		/* SEV-specific errors that can still happen. */
> +	case SEV_RET_BAD_SIGNATURE:
> +		/* No state changes made. Not a hardware error. */
> +		dev_warn(sev->dev, "Firmware image signature is bad\n");
> +		return FW_UPLOAD_ERR_FW_INVALID;
> +	case SEV_RET_INVALID_PLATFORM_STATE:
> +		/* Calling at the wrong time. Not a hardware error. */
> +		dev_warn(sev->dev, "Firmware not updated as SEV in INIT state\n");
> +		return FW_UPLOAD_ERR_BUSY;
> +	case SEV_RET_HWSEV_RET_UNSAFE:
> +		dev_err(sev->dev, "Firmware is unstable. Reset your machine!!!\n");
> +		return FW_UPLOAD_ERR_HW_ERROR;
> +		/* Kernel bug cases. */
> +	case SEV_RET_INVALID_PARAM:
> +		dev_err(sev->dev, "Download-firmware-EX invalid parameter\n");
> +		return FW_UPLOAD_ERR_RW_ERROR;
> +	case SEV_RET_INVALID_ADDRESS:
> +		dev_err(sev->dev, "Download-firmware-EX invalid address\n");
> +		return FW_UPLOAD_ERR_RW_ERROR;
> +	default:
> +		dev_err(sev->dev, "Unhandled download_firmware_ex err %d\n", psp_ret);
> +		return FW_UPLOAD_ERR_HW_ERROR;
> +	}
> +}
> +
> +static enum fw_upload_err snp_dlfw_ex_write(struct fw_upload *fwl, const u8 *data,
> +					    u32 offset, u32 size, u32 *written)
> +{
> +	struct sev_data_download_firmware_ex *data_ex;
> +	struct sev_data_snp_guest_status status_data;
> +	struct sev_device *sev = fwl->dd_handle;
> +	void *snp_guest_status, *fw_dest;
> +	u8 api_major, api_minor, build;
> +	int ret, error, order;
> +	struct page *p;
> +	u64 data_size;
> +	bool cancel;
> +
> +	if (!sev)
> +		return FW_UPLOAD_ERR_HW_ERROR;
> +
> +	mutex_lock(&sev->fw_lock);
> +	cancel = sev->fw_cancel;
> +	mutex_unlock(&sev->fw_lock);
> +
> +	if (cancel)
> +		return FW_UPLOAD_ERR_CANCELED;
> +
> +	/*
> +	 * SEV firmware update is a one-shot update operation, the write()
> +	 * callback to be invoked multiple times for the same update is
> +	 * unexpected.
> +	 */
> +	if (offset)
> +		return FW_UPLOAD_ERR_INVALID_SIZE;
> +
> +	if (sev_get_api_version())
> +		return FW_UPLOAD_ERR_HW_ERROR;
> +
> +	api_major = sev->api_major;
> +	api_minor = sev->api_minor;
> +	build     = sev->build;
> +
> +	data_size = ALIGN(sizeof(struct sev_data_download_firmware_ex),
> +			  SEV_FW_ALIGNMENT);
> +
> +	order = get_order(size + data_size);
> +	p = alloc_pages(GFP_KERNEL, order);
> +	if (!p) {
> +		ret = FW_UPLOAD_ERR_INVALID_SIZE;
> +		goto fw_err;
> +	}
> +
> +	/*
> +	 * Copy firmware data to a kernel allocated contiguous
> +	 * memory region.
> +	 */
> +	data_ex = page_address(p);
> +	fw_dest = page_address(p) + data_size;
> +	memset(data_ex, 0, data_size);
> +	memcpy(fw_dest, data, size);
> +
> +	data_ex->address = __psp_pa(fw_dest);
> +	data_ex->len = size;
> +	data_ex->cmdlen = sizeof(struct sev_data_download_firmware_ex);
> +
> +	/*
> +	 * SNP_COMMIT should be issued explicitly to commit the updated
> +	 * firmware after guest context pages have been updated.
> +	 */
> +
> +	ret = sev_do_cmd(SEV_CMD_SNP_DOWNLOAD_FIRMWARE_EX, data_ex, &error);
> +
> +	if (ret) {
> +		ret = snp_dlfw_ex_err_translate(sev, error);
> +		goto free_err;
> +	}
> +
> +	__free_pages(p, order);
> +
> +	/* Need to do a DF_FLUSH after live firmware update */
> +	wbinvd_on_all_cpus();
> +	ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, &error);
> +	if (ret) {
> +		dev_dbg(sev->dev, "DF_FLUSH error %d\n", error);
> +		ret = FW_UPLOAD_ERR_HW_ERROR;
> +		goto fw_err;
> +	}
> +
> +	sev_get_api_version();
> +
> +	/*
> +	 * Force an update of guest context pages after SEV firmware
> +	 * live update by issuing SNP_GUEST_STATUS on all guest
> +	 * context pages.
> +	 */
> +	snp_guest_status = sev_fw_alloc(PAGE_SIZE);
> +	if (!snp_guest_status) {
> +		ret = FW_UPLOAD_ERR_INVALID_SIZE;
> +		goto fw_err;
> +	}
> +
> +	/*
> +	 * After the last bound asid-to-gctx page is snp_unbound_gctx_end-many
> +	 * unbound gctx pages that also need updating.
> +	 */
> +	for (int i = 1; i <= sev->last_snp_asid + sev->snp_unbound_gctx_end; i++) {
> +		if (sev->snp_asid_to_gctx_pages_map[i]) {
> +			status_data.gctx_paddr = sev->snp_asid_to_gctx_pages_map[i];
> +			status_data.address = __psp_pa(snp_guest_status);
> +			ret = sev_do_cmd(SEV_CMD_SNP_GUEST_STATUS, &status_data, &error);
> +			if (ret) {
> +				/*
> +				 * Handle race with SNP VM being destroyed/decommissoned,
> +				 * if guest context page invalid error is returned,
> +				 * assume guest has been destroyed.
> +				 */
> +				if (error == SEV_RET_INVALID_GUEST)
> +					continue;
> +				sev->synthetic_restore_required = true;
> +				dev_err(sev->dev, "SNP GCTX update error: %#x\n", error);
> +				dev_err(sev->dev, "Roll back SNP firmware!\n");
> +				snp_free_firmware_page(snp_guest_status);
> +				ret = FW_UPLOAD_ERR_RW_ERROR;
> +				goto fw_err;
> +			}
> +		}
> +	}
> +	snp_free_firmware_page(snp_guest_status);
> +
> +	if (api_major != sev->api_major || api_minor != sev->api_minor ||
> +	    build != sev->build) {
> +		dev_info(sev->dev, "SEV firmware updated from %d.%d.%d to %d.%d.%d\n",
> +			 api_major, api_minor, build,
> +			 sev->api_major, sev->api_minor, sev->build);
> +	} else {
> +		dev_info(sev->dev, "SEV firmware same as old %d.%d.%d\n",
> +			 api_major, api_minor, build);
> +	}
> +
> +	*written = size;
> +	return FW_UPLOAD_ERR_NONE;
> +
> +free_err:
> +	__free_pages(p, order);
> +fw_err:
> +	return ret;
> +}
> +
> +static const struct fw_upload_ops snp_dlfw_ex_ops = {
> +	.prepare = snp_dlfw_ex_prepare,
> +	.write = snp_dlfw_ex_write,
> +	.poll_complete = snp_dlfw_ex_poll_complete,
> +	.cancel = snp_dlfw_ex_cancel,
> +};
> +
> +static void sev_snp_dev_init_firmware_upload(struct sev_device *sev)
> +{
> +	struct fw_upload *fwl;
> +
> +	fwl = firmware_upload_register(THIS_MODULE, sev->dev, "snp_dlfw_ex", &snp_dlfw_ex_ops, sev);
> +
> +	if (IS_ERR(fwl))
> +		dev_err(sev->dev, "SEV firmware upload initialization error %ld\n", PTR_ERR(fwl));
> +
> +	sev->fwl = fwl;
> +	mutex_init(&sev->fw_lock);
> +}
> +
> +static void sev_snp_destroy_firmware_upload(struct sev_device *sev)
> +{
> +	firmware_upload_unregister(sev->fwl);
> +}
> +
> +/*
> + * After a gctx is created, it is used by snp_launch_start before getting
> + * bound to an asid. The launch protocol allocates an asid before creating a
> + * matching gctx page, so there should never be more unbound gctx pages than
> + * there are possible SNP asids.
> + *
> + * The unbound gctx pages must be updated after executing DOWNLOAD_FIRMWARE_EX
> + * and before committing the firmware.
> + */
> +static void snp_gctx_create_track_locked(struct sev_device *sev, void *data)
> +{
> +	struct sev_data_snp_addr *gctx_create = data;
> +
> +	/* This condition should never happen, but is needed for memory safety. */
> +	if (sev->snp_unbound_gctx_end >= sev->last_snp_asid) {
> +		dev_warn(sev->dev, "Too many unbound SNP GCTX pages to track\n");
> +		return;
> +	}
> +
> +	sev->snp_unbound_gctx_pages[sev->snp_unbound_gctx_end] = gctx_create->address;
> +	sev->snp_unbound_gctx_end++;
> +}
> +
> +/*
> + * PREREQUISITE: The snp_activate command was successful, meaning the asid
> + * is in the acceptable range 1..sev->last_snp_asid.
> + *
> + * The gctx_paddr must be in the unbound gctx buffer.
> + */
> +static void snp_activate_track_locked(struct sev_device *sev, void *data)
> +{
> +	struct sev_data_snp_activate *data_activate = data;
> +
> +	sev->snp_asid_to_gctx_pages_map[data_activate->asid] = data_activate->gctx_paddr;
> +
> +	for (int i = 0; i < sev->snp_unbound_gctx_end; i++) {
> +		if (sev->snp_unbound_gctx_pages[i] == data_activate->gctx_paddr) {
> +			/*
> +			 * Swap the last unbound gctx page with the now-bound
> +			 * gctx page to shrink the buffer.
> +			 */
> +			sev->snp_unbound_gctx_end--;
> +			sev->snp_unbound_gctx_pages[i] =
> +				sev->snp_unbound_gctx_pages[sev->snp_unbound_gctx_end];
> +			sev->snp_unbound_gctx_pages[sev->snp_unbound_gctx_end] = 0;
> +			break;
> +		}
> +	}
> +}
> +
> +static void snp_decommission_track_locked(struct sev_device *sev, void *data)
> +{
> +	struct sev_data_snp_addr *data_decommission = data;
> +
> +	for (int i = 1; i <= sev->last_snp_asid; i++) {
> +		if (sev->snp_asid_to_gctx_pages_map[i] == data_decommission->address) {
> +			sev->snp_asid_to_gctx_pages_map[i] = 0;
> +			break;
> +		}
> +	}
> +}
> +
> +static void snp_cmd_bookkeeping_locked(int cmd, struct sev_device *sev, void *data)
> +{
> +	if (!sev->snp_asid_to_gctx_pages_map)
> +		return;
> +
> +	switch (cmd) {
> +	case SEV_CMD_SNP_GCTX_CREATE:
> +		snp_gctx_create_track_locked(sev, data);
> +		break;
> +	case SEV_CMD_SNP_ACTIVATE:
> +		snp_activate_track_locked(sev, data);
> +		break;
> +	case SEV_CMD_SNP_DECOMMISSION:
> +		snp_decommission_track_locked(sev, data);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +static int sev_snp_platform_init_firmware_upload(struct sev_device *sev)
> +{
> +	u32 max_snp_asid;
> +
> +	/*
> +	 * cpuid_edx(0x8000001f) is the minimum SEV ASID, hence the exclusive
> +	 * maximum SEV-SNP ASID. Save the inclusive maximum to avoid confusing
> +	 * logic elsewhere.
> +	 */
> +	max_snp_asid = cpuid_edx(0x8000001f);
> +	sev->last_snp_asid = max_snp_asid - 1;
> +	if (sev->last_snp_asid) {
> +		sev->snp_asid_to_gctx_pages_map = devm_kmalloc_array(
> +			sev->dev, max_snp_asid * 2, sizeof(u64), GFP_KERNEL | __GFP_ZERO);
> +		sev->snp_unbound_gctx_pages = &sev->snp_asid_to_gctx_pages_map[max_snp_asid];
> +		if (!sev->snp_asid_to_gctx_pages_map) {
> +			kfree(snp_range_list);
> +			dev_err(sev->dev,
> +				"SEV-SNP: snp_asid_to_gctx_pages_map memory allocation failed\n");
> +			return -ENOMEM;
> +		}
> +	}
> +	return 0;
> +}
> +
> +#else
> +
> +static int sev_snp_platform_init_firmware_upload(struct sev_device *sev) { return 0; }
> +static void sev_snp_dev_init_firmware_upload(struct sev_device *sev) { }
> +static void sev_snp_destroy_firmware_upload(struct sev_device *sev) { }
> +static void snp_cmd_bookkeeping_locked(int cmd, struct sev_device *sev, void *data) { }
> +#endif
> +
>  int sev_dev_init(struct psp_device *psp)
>  {
>  	struct device *dev = psp->dev;
> @@ -2265,6 +2644,8 @@ int sev_dev_init(struct psp_device *psp)
>  	if (ret)
>  		goto e_irq;
>  
> +	sev_snp_dev_init_firmware_upload(sev);
> +
>  	dev_notice(dev, "sev enabled\n");
>  
>  	return 0;
> @@ -2343,6 +2724,8 @@ void sev_dev_destroy(struct psp_device *psp)
>  		kref_put(&misc_dev->refcount, sev_exit);
>  
>  	psp_clear_sev_irq_handler(psp);
> +
> +	sev_snp_destroy_firmware_upload(sev);
>  }
>  
>  static int snp_shutdown_on_panic(struct notifier_block *nb,
> diff --git a/drivers/crypto/ccp/sev-dev.h b/drivers/crypto/ccp/sev-dev.h
> index 3e4e5574e88a3..d6280688675d9 100644
> --- a/drivers/crypto/ccp/sev-dev.h
> +++ b/drivers/crypto/ccp/sev-dev.h
> @@ -57,6 +57,20 @@ struct sev_device {
>  	bool cmd_buf_backup_active;
>  
>  	bool snp_initialized;
> +
> +#ifdef CONFIG_FW_UPLOAD
> +	/* Lock to protect fw_cancel */
> +	struct mutex fw_lock;
> +	struct fw_upload *fwl;
> +	bool fw_cancel;
> +
> +	/* Firmware update management. */
> +	u32 last_snp_asid;
> +	bool synthetic_restore_required;
> +	u64 *snp_asid_to_gctx_pages_map;
> +	u64 *snp_unbound_gctx_pages;
> +	u32 snp_unbound_gctx_end;
> +#endif /* CONFIG_FW_UPLOAD */
>  };
>  
>  int sev_dev_init(struct psp_device *psp);
> diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
> index 903ddfea85850..ff7f9e33f3335 100644
> --- a/include/linux/psp-sev.h
> +++ b/include/linux/psp-sev.h
> @@ -16,6 +16,15 @@
>  
>  #define SEV_FW_BLOB_MAX_SIZE	0x4000	/* 16KB */
>  
> +/*
> + * 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.
> + */
> +#define SEV_FW_ALIGNMENT	32
> +
>  /**
>   * SEV platform state
>   */
> @@ -185,6 +194,23 @@ struct sev_data_download_firmware {
>  	u32 len;				/* In */
>  } __packed;
>  
> +/**
> + * struct sev_data_download_firmware_ex - DOWNLOAD_FIRMWARE_EX command parameters
> + *
> + * @length: length of this command buffer
> + * @address: physical address of firmware image
> + * @len: len of the firmware image
> + * @commit: automatically commit the newly installed image
> + */
> +struct sev_data_download_firmware_ex {
> +	u32 cmdlen;				/* In */
> +	u32 reserved;				/* in */
> +	u64 address;				/* In */
> +	u32 len;				/* In */
> +	u32 commit:1;				/* In */
> +	u32 reserved2:31;			/* In */
> +} __packed;
> +
>  /**
>   * struct sev_data_get_id - GET_ID command parameters
>   *
> @@ -797,10 +823,13 @@ struct sev_data_snp_shutdown_ex {
>   * @probe: True if this is being called as part of CCP module probe, which
>   *  will defer SEV_INIT/SEV_INIT_EX firmware initialization until needed
>   *  unless psp_init_on_probe module param is set
> + * @supports_download_firmware_ex: True if legacy SEV/SEV-ES guests are not
> + *  being launched via KVM
>   */
>  struct sev_platform_init_args {
>  	int error;
>  	bool probe;
> +	bool supports_download_firmware_ex;
>  };
>  
>  /**
> diff --git a/include/uapi/linux/psp-sev.h b/include/uapi/linux/psp-sev.h
> index 832c15d9155bd..936464d4f282a 100644
> --- a/include/uapi/linux/psp-sev.h
> +++ b/include/uapi/linux/psp-sev.h
> @@ -80,6 +80,11 @@ typedef enum {
>  	SEV_RET_INVALID_PAGE_OWNER,
>  	SEV_RET_INVALID_PAGE_AEAD_OFLOW,
>  	SEV_RET_RMP_INIT_REQUIRED,
> +	SEV_RET_BAD_SVN,
> +	SEV_RET_BAD_VERSION,
> +	SEV_RET_SHUTDOWN_REQUIRED,
> +	SEV_RET_UPDATE_FAILED,
> +	SEV_RET_RESTORE_REQUIRED,
>  	SEV_RET_MAX,
>  } sev_ret_code;
>  

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