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| author | Tom Lendacky <thomas.lendacky@amd.com> | 2022-03-07 15:33:32 -0600 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2022-04-06 17:06:49 +0200 |
| commit | 0afb6b660a6b58cb336d1175ed687bf9525849a4 (patch) | |
| tree | 9f12fd9423ad05806c230dd998e9c7a18e77212a /arch/x86/include/asm/sev.h | |
| parent | dc3f3d2474b80eaee8be89f4c5eb344f10648f42 (diff) | |
| download | lwn-0afb6b660a6b58cb336d1175ed687bf9525849a4.tar.gz lwn-0afb6b660a6b58cb336d1175ed687bf9525849a4.zip | |
x86/sev: Use SEV-SNP AP creation to start secondary CPUs
To provide a more secure way to start APs under SEV-SNP, use the SEV-SNP
AP Creation NAE event. This allows for guest control over the AP register
state rather than trusting the hypervisor with the SEV-ES Jump Table
address.
During native_smp_prepare_cpus(), invoke an SEV-SNP function that, if
SEV-SNP is active, will set/override apic->wakeup_secondary_cpu. This
will allow the SEV-SNP AP Creation NAE event method to be used to boot
the APs. As a result of installing the override when SEV-SNP is active,
this method of starting the APs becomes the required method. The override
function will fail to start the AP if the hypervisor does not have
support for AP creation.
[ bp: Work in forgotten review comments. ]
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20220307213356.2797205-23-brijesh.singh@amd.com
Diffstat (limited to 'arch/x86/include/asm/sev.h')
| -rw-r--r-- | arch/x86/include/asm/sev.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index feeb93e6ec97..a3203b2caaca 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -66,6 +66,8 @@ extern bool handle_vc_boot_ghcb(struct pt_regs *regs); /* RMP page size */ #define RMP_PG_SIZE_4K 0 +#define RMPADJUST_VMSA_PAGE_BIT BIT(16) + #ifdef CONFIG_AMD_MEM_ENCRYPT extern struct static_key_false sev_es_enable_key; extern void __sev_es_ist_enter(struct pt_regs *regs); @@ -130,6 +132,7 @@ void __init early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op); void snp_set_memory_shared(unsigned long vaddr, unsigned int npages); void snp_set_memory_private(unsigned long vaddr, unsigned int npages); +void snp_set_wakeup_secondary_cpu(void); #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } @@ -146,6 +149,7 @@ early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned i static inline void __init snp_prep_memory(unsigned long paddr, unsigned int sz, enum psc_op op) { } static inline void snp_set_memory_shared(unsigned long vaddr, unsigned int npages) { } static inline void snp_set_memory_private(unsigned long vaddr, unsigned int npages) { } +static inline void snp_set_wakeup_secondary_cpu(void) { } #endif #endif |