Merge tag 'x86_sev_for_v6.10_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (964bbdfd) · Commits · git / linux-net

arch/x86/boot/compressed/sev.c

+95 −102

Original line number	Diff line number	Diff line
		@@ -335,26 +335,6 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code)
		sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SEV_ES_GEN_REQ);
		}

		static void enforce_vmpl0(void)
		{
		u64 attrs;
		int err;

		/*
		* RMPADJUST modifies RMP permissions of a lesser-privileged (numerically
		* higher) privilege level. Here, clear the VMPL1 permission mask of the
		* GHCB page. If the guest is not running at VMPL0, this will fail.
		*
		* If the guest is running at VMPL0, it will succeed. Even if that operation
		* modifies permission bits, it is still ok to do so currently because Linux
		* SNP guests are supported only on VMPL0 so VMPL1 or higher permission masks
		* changing is a don't-care.
		*/
		attrs = 1;
		if (rmpadjust((unsigned long)&boot_ghcb_page, RMP_PG_SIZE_4K, attrs))
		sev_es_terminate(SEV_TERM_SET_LINUX, GHCB_TERM_NOT_VMPL0);
		}

		/*
		* SNP_FEATURES_IMPL_REQ is the mask of SNP features that will need
		* guest side implementation for proper functioning of the guest. If any
		@@ -413,6 +393,85 @@ void snp_check_features(void)
		}
		}

		/* Search for Confidential Computing blob in the EFI config table. */
		static struct cc_blob_sev_info find_cc_blob_efi(struct boot_params bp)
		{
		unsigned long cfg_table_pa;
		unsigned int cfg_table_len;
		int ret;

		ret = efi_get_conf_table(bp, &cfg_table_pa, &cfg_table_len);
		if (ret)
		return NULL;

		return (struct cc_blob_sev_info *)efi_find_vendor_table(bp, cfg_table_pa,
		cfg_table_len,
		EFI_CC_BLOB_GUID);
		}

		/*
		* Initial set up of SNP relies on information provided by the
		* Confidential Computing blob, which can be passed to the boot kernel
		* by firmware/bootloader in the following ways:
		*
		* - via an entry in the EFI config table
		* - via a setup_data structure, as defined by the Linux Boot Protocol
		*
		* Scan for the blob in that order.
		*/
		static struct cc_blob_sev_info find_cc_blob(struct boot_params bp)
		{
		struct cc_blob_sev_info *cc_info;

		cc_info = find_cc_blob_efi(bp);
		if (cc_info)
		goto found_cc_info;

		cc_info = find_cc_blob_setup_data(bp);
		if (!cc_info)
		return NULL;

		found_cc_info:
		if (cc_info->magic != CC_BLOB_SEV_HDR_MAGIC)
		sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SNP_UNSUPPORTED);

		return cc_info;
		}

		/*
		* Indicate SNP based on presence of SNP-specific CC blob. Subsequent checks
		* will verify the SNP CPUID/MSR bits.
		*/
		static bool early_snp_init(struct boot_params *bp)
		{
		struct cc_blob_sev_info *cc_info;

		if (!bp)
		return false;

		cc_info = find_cc_blob(bp);
		if (!cc_info)
		return false;

		/*
		* If a SNP-specific Confidential Computing blob is present, then
		* firmware/bootloader have indicated SNP support. Verifying this
		* involves CPUID checks which will be more reliable if the SNP
		* CPUID table is used. See comments over snp_setup_cpuid_table() for
		* more details.
		*/
		setup_cpuid_table(cc_info);

		/*
		* Pass run-time kernel a pointer to CC info via boot_params so EFI
		* config table doesn't need to be searched again during early startup
		* phase.
		*/
		bp->cc_blob_address = (u32)(unsigned long)cc_info;

		return true;
		}

		/*
		* sev_check_cpu_support - Check for SEV support in the CPU capabilities
		*
		@@ -463,7 +522,7 @@ void sev_enable(struct boot_params *bp)
		bp->cc_blob_address = 0;

		/*
		* Do an initial SEV capability check before snp_init() which
		* Do an initial SEV capability check before early_snp_init() which
		* loads the CPUID page and the same checks afterwards are done
		* without the hypervisor and are trustworthy.
		*
		@@ -478,7 +537,7 @@ void sev_enable(struct boot_params *bp)
		* Setup/preliminary detection of SNP. This will be sanity-checked
		* against CPUID/MSR values later.
		*/
		snp = snp_init(bp);
		snp = early_snp_init(bp);

		/* Now repeat the checks with the SNP CPUID table. */

		@@ -509,7 +568,20 @@ void sev_enable(struct boot_params *bp)
		if (!(get_hv_features() & GHCB_HV_FT_SNP))
		sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SNP_UNSUPPORTED);

		enforce_vmpl0();
		/*
		* Enforce running at VMPL0.
		*
		* RMPADJUST modifies RMP permissions of a lesser-privileged (numerically
		* higher) privilege level. Here, clear the VMPL1 permission mask of the
		* GHCB page. If the guest is not running at VMPL0, this will fail.
		*
		* If the guest is running at VMPL0, it will succeed. Even if that operation
		* modifies permission bits, it is still ok to do so currently because Linux
		* SNP guests running at VMPL0 only run at VMPL0, so VMPL1 or higher
		* permission mask changes are a don't-care.
		*/
		if (rmpadjust((unsigned long)&boot_ghcb_page, RMP_PG_SIZE_4K, 1))
		sev_es_terminate(SEV_TERM_SET_LINUX, GHCB_TERM_NOT_VMPL0);
		}

		if (snp && !(sev_status & MSR_AMD64_SEV_SNP_ENABLED))
		@@ -535,85 +607,6 @@ u64 sev_get_status(void)
		return m.q;
		}

		/* Search for Confidential Computing blob in the EFI config table. */
		static struct cc_blob_sev_info find_cc_blob_efi(struct boot_params bp)
		{
		unsigned long cfg_table_pa;
		unsigned int cfg_table_len;
		int ret;

		ret = efi_get_conf_table(bp, &cfg_table_pa, &cfg_table_len);
		if (ret)
		return NULL;

		return (struct cc_blob_sev_info *)efi_find_vendor_table(bp, cfg_table_pa,
		cfg_table_len,
		EFI_CC_BLOB_GUID);
		}

		/*
		* Initial set up of SNP relies on information provided by the
		* Confidential Computing blob, which can be passed to the boot kernel
		* by firmware/bootloader in the following ways:
		*
		* - via an entry in the EFI config table
		* - via a setup_data structure, as defined by the Linux Boot Protocol
		*
		* Scan for the blob in that order.
		*/
		static struct cc_blob_sev_info find_cc_blob(struct boot_params bp)
		{
		struct cc_blob_sev_info *cc_info;

		cc_info = find_cc_blob_efi(bp);
		if (cc_info)
		goto found_cc_info;

		cc_info = find_cc_blob_setup_data(bp);
		if (!cc_info)
		return NULL;

		found_cc_info:
		if (cc_info->magic != CC_BLOB_SEV_HDR_MAGIC)
		sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SNP_UNSUPPORTED);

		return cc_info;
		}

		/*
		* Indicate SNP based on presence of SNP-specific CC blob. Subsequent checks
		* will verify the SNP CPUID/MSR bits.
		*/
		bool snp_init(struct boot_params *bp)
		{
		struct cc_blob_sev_info *cc_info;

		if (!bp)
		return false;

		cc_info = find_cc_blob(bp);
		if (!cc_info)
		return false;

		/*
		* If a SNP-specific Confidential Computing blob is present, then
		* firmware/bootloader have indicated SNP support. Verifying this
		* involves CPUID checks which will be more reliable if the SNP
		* CPUID table is used. See comments over snp_setup_cpuid_table() for
		* more details.
		*/
		setup_cpuid_table(cc_info);

		/*
		* Pass run-time kernel a pointer to CC info via boot_params so EFI
		* config table doesn't need to be searched again during early startup
		* phase.
		*/
		bp->cc_blob_address = (u32)(unsigned long)cc_info;

		return true;
		}

		void sev_prep_identity_maps(unsigned long top_level_pgt)
		{
		/*

arch/x86/include/asm/sev.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -140,7 +140,7 @@ struct secrets_os_area {
		#define VMPCK_KEY_LEN 32

		/* See the SNP spec version 0.9 for secrets page format */
		struct snp_secrets_page_layout {
		struct snp_secrets_page {
		u32 version;
		u32 imien : 1,
		rsvd1 : 31;

arch/x86/kernel/sev.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -648,7 +648,7 @@ static u64 __init get_secrets_page(void)

		static u64 __init get_snp_jump_table_addr(void)
		{
		struct snp_secrets_page_layout *layout;
		struct snp_secrets_page *secrets;
		void __iomem *mem;
		u64 pa, addr;

		@@ -662,9 +662,9 @@ static u64 __init get_snp_jump_table_addr(void)
		return 0;
		}

		layout = (__force struct snp_secrets_page_layout *)mem;
		secrets = (__force struct snp_secrets_page *)mem;

		addr = layout->os_area.ap_jump_table_pa;
		addr = secrets->os_area.ap_jump_table_pa;
		iounmap(mem);

		return addr;

drivers/virt/coco/sev-guest/sev-guest.c

+14 −14

Original line number	Diff line number	Diff line
		@@ -59,7 +59,7 @@ struct snp_guest_dev {
		*/
		struct snp_guest_msg secret_request, secret_response;

		struct snp_secrets_page_layout *layout;
		struct snp_secrets_page *secrets;
		struct snp_req_data input;
		union {
		struct snp_report_req report;
		@@ -743,26 +743,26 @@ static const struct file_operations snp_guest_fops = {
		.unlocked_ioctl = snp_guest_ioctl,
		};

		static u8 get_vmpck(int id, struct snp_secrets_page_layout layout, u32 **seqno)
		static u8 get_vmpck(int id, struct snp_secrets_page secrets, u32 **seqno)
		{
		u8 *key = NULL;

		switch (id) {
		case 0:
		*seqno = &layout->os_area.msg_seqno_0;
		key = layout->vmpck0;
		*seqno = &secrets->os_area.msg_seqno_0;
		key = secrets->vmpck0;
		break;
		case 1:
		*seqno = &layout->os_area.msg_seqno_1;
		key = layout->vmpck1;
		*seqno = &secrets->os_area.msg_seqno_1;
		key = secrets->vmpck1;
		break;
		case 2:
		*seqno = &layout->os_area.msg_seqno_2;
		key = layout->vmpck2;
		*seqno = &secrets->os_area.msg_seqno_2;
		key = secrets->vmpck2;
		break;
		case 3:
		*seqno = &layout->os_area.msg_seqno_3;
		key = layout->vmpck3;
		*seqno = &secrets->os_area.msg_seqno_3;
		key = secrets->vmpck3;
		break;
		default:
		break;
		@@ -897,8 +897,8 @@ static void unregister_sev_tsm(void *data)

		static int __init sev_guest_probe(struct platform_device *pdev)
		{
		struct snp_secrets_page_layout *layout;
		struct sev_guest_platform_data *data;
		struct snp_secrets_page *secrets;
		struct device *dev = &pdev->dev;
		struct snp_guest_dev *snp_dev;
		struct miscdevice *misc;
		@@ -916,7 +916,7 @@ static int __init sev_guest_probe(struct platform_device *pdev)
		if (!mapping)
		return -ENODEV;

		layout = (__force void *)mapping;
		secrets = (__force void *)mapping;

		ret = -ENOMEM;
		snp_dev = devm_kzalloc(&pdev->dev, sizeof(struct snp_guest_dev), GFP_KERNEL);
		@@ -924,7 +924,7 @@ static int __init sev_guest_probe(struct platform_device *pdev)
		goto e_unmap;

		ret = -EINVAL;
		snp_dev->vmpck = get_vmpck(vmpck_id, layout, &snp_dev->os_area_msg_seqno);
		snp_dev->vmpck = get_vmpck(vmpck_id, secrets, &snp_dev->os_area_msg_seqno);
		if (!snp_dev->vmpck) {
		dev_err(dev, "invalid vmpck id %d\n", vmpck_id);
		goto e_unmap;
		@@ -938,7 +938,7 @@ static int __init sev_guest_probe(struct platform_device *pdev)

		platform_set_drvdata(pdev, snp_dev);
		snp_dev->dev = dev;
		snp_dev->layout = layout;
		snp_dev->secrets = secrets;

		/* Allocate the shared page used for the request and response message. */
		snp_dev->request = alloc_shared_pages(dev, sizeof(struct snp_guest_msg));