Commit 18ea89ea authored by Tom Lendacky's avatar Tom Lendacky Committed by Ingo Molnar
Browse files

x86/sev: Share the sev_secrets_pa value again 



This commits breaks SNP guests:

  234cf67f ("x86/sev: Split off startup code from core code")

The SNP guest boots, but no longer has access to the VMPCK keys needed
to communicate with the ASP, which is used, for example, to obtain an
attestation report.

The secrets_pa value is defined as static in both startup.c and
core.c. It is set by a function in startup.c and so when used in
core.c its value will be 0.

Share it again and add the sev_ prefix to put it into the global
SEV symbols namespace.

[ mingo: Renamed to sev_secrets_pa ]

Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Acked-by: default avatarArd Biesheuvel <ardb@kernel.org>
Cc: Dionna Amalie Glaze <dionnaglaze@google.com>
Cc: Kevin Loughlin <kevinloughlin@google.com>
Link: https://lore.kernel.org/r/cf878810-81ed-3017-52c6-ce6aa41b5f01@amd.com
parent 121c335b

arch/x86/boot/startup/sev-startup.c

+2 −2
Original line number Diff line number Diff line
@@ -55,7 +55,7 @@ struct ghcb *boot_ghcb __section(".data"); 
u64 sev_hv_features __ro_after_init;



/* Secrets page physical address from the CC blob */

static u64 secrets_pa __ro_after_init;

u64 sev_secrets_pa __ro_after_init;



/* For early boot SVSM communication */

struct svsm_ca boot_svsm_ca_page __aligned(PAGE_SIZE);
@@ -1367,7 +1367,7 @@ bool __head snp_init(struct boot_params *bp) 
		return false;



	if (cc_info->secrets_phys && cc_info->secrets_len == PAGE_SIZE)

		secrets_pa = cc_info->secrets_phys;

		sev_secrets_pa = cc_info->secrets_phys;

	else

		return false;

arch/x86/coco/sev/core.c

+2 −5
Original line number Diff line number Diff line
@@ -80,9 +80,6 @@ static const char * const sev_status_feat_names[] = { 
	[MSR_AMD64_SNP_SMT_PROT_BIT]		= "SMTProt",

};



/* Secrets page physical address from the CC blob */

static u64 secrets_pa __ro_after_init;



/*

 * For Secure TSC guests, the BSP fetches TSC_INFO using SNP guest messaging and

 * initializes snp_tsc_scale and snp_tsc_offset. These values are replicated
@@ -109,7 +106,7 @@ static u64 __init get_snp_jump_table_addr(void) 
	void __iomem *mem;

	u64 addr;



	mem = ioremap_encrypted(secrets_pa, PAGE_SIZE);

	mem = ioremap_encrypted(sev_secrets_pa, PAGE_SIZE);

	if (!mem) {

		pr_err("Unable to locate AP jump table address: failed to map the SNP secrets page.\n");

		return 0;
@@ -1599,7 +1596,7 @@ struct snp_msg_desc *snp_msg_alloc(void) 
	if (!mdesc)

		return ERR_PTR(-ENOMEM);



	mem = ioremap_encrypted(secrets_pa, PAGE_SIZE);

	mem = ioremap_encrypted(sev_secrets_pa, PAGE_SIZE);

	if (!mem)

		goto e_free_mdesc;

arch/x86/include/asm/sev-internal.h

+1 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
extern struct ghcb boot_ghcb_page;

extern struct ghcb *boot_ghcb;

extern u64 sev_hv_features;

extern u64 sev_secrets_pa;



/* #VC handler runtime per-CPU data */

struct sev_es_runtime_data {