| Message ID | ba565128b88661a656fc3972f01bb2e295158a15.1627424774.git.thomas.lendacky@amd.com (mailing list archive) |
|---|---|
| State | Deferred, archived |
| Headers | show |
| Series | Implement generic prot_guest_has() helper function | expand |
On Tue, Jul 27, 2021 at 05:26:09PM -0500, Tom Lendacky wrote: > @@ -48,7 +47,7 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th) > if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT)) > th->flags |= TH_FLAGS_SME_ACTIVE; > > - if (sev_es_active()) { > + if (prot_guest_has(PATTR_GUEST_PROT_STATE)) { > /* > * Skip the call to verify_cpu() in secondary_startup_64 as it > * will cause #VC exceptions when the AP can't handle them yet. Not sure how TDX will handle AP booting, are you sure it needs this special setup as well? Otherwise a check for SEV-ES would be better instead of the generic PATTR_GUEST_PROT_STATE. Regards, Joerg
On 8/2/21 5:45 AM, Joerg Roedel wrote: > On Tue, Jul 27, 2021 at 05:26:09PM -0500, Tom Lendacky wrote: >> @@ -48,7 +47,7 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th) >> if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT)) >> th->flags |= TH_FLAGS_SME_ACTIVE; >> >> - if (sev_es_active()) { >> + if (prot_guest_has(PATTR_GUEST_PROT_STATE)) { >> /* >> * Skip the call to verify_cpu() in secondary_startup_64 as it >> * will cause #VC exceptions when the AP can't handle them yet. > > Not sure how TDX will handle AP booting, are you sure it needs this > special setup as well? Otherwise a check for SEV-ES would be better > instead of the generic PATTR_GUEST_PROT_STATE. Yes, I'm not sure either. I figure that change can be made, if needed, as part of the TDX support. Thanks, Tom > > Regards, > > Joerg >
On 8/9/21 2:59 PM, Tom Lendacky wrote: >> Not sure how TDX will handle AP booting, are you sure it needs this >> special setup as well? Otherwise a check for SEV-ES would be better >> instead of the generic PATTR_GUEST_PROT_STATE. > Yes, I'm not sure either. I figure that change can be made, if needed, as > part of the TDX support. We don't plan to set PROT_STATE. So it does not affect TDX. For SMP, we use MADT ACPI table for AP booting.
diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 7e25de37c148..797146e0cd6b 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -50,7 +50,6 @@ void __init mem_encrypt_free_decrypted_mem(void); void __init mem_encrypt_init(void); void __init sev_es_init_vc_handling(void); -bool sev_es_active(void); bool amd_prot_guest_has(unsigned int attr); #define __bss_decrypted __section(".bss..decrypted") @@ -74,7 +73,6 @@ static inline void __init sme_encrypt_kernel(struct boot_params *bp) { } static inline void __init sme_enable(struct boot_params *bp) { } static inline void sev_es_init_vc_handling(void) { } -static inline bool sev_es_active(void) { return false; } static inline bool amd_prot_guest_has(unsigned int attr) { return false; } static inline int __init diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index a6895e440bc3..66a4ab9d95d7 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -11,7 +11,7 @@ #include <linux/sched/debug.h> /* For show_regs() */ #include <linux/percpu-defs.h> -#include <linux/mem_encrypt.h> +#include <linux/protected_guest.h> #include <linux/printk.h> #include <linux/mm_types.h> #include <linux/set_memory.h> @@ -615,7 +615,7 @@ int __init sev_es_efi_map_ghcbs(pgd_t *pgd) int cpu; u64 pfn; - if (!sev_es_active()) + if (!prot_guest_has(PATTR_SEV_ES)) return 0; pflags = _PAGE_NX | _PAGE_RW; @@ -774,7 +774,7 @@ void __init sev_es_init_vc_handling(void) BUILD_BUG_ON(offsetof(struct sev_es_runtime_data, ghcb_page) % PAGE_SIZE); - if (!sev_es_active()) + if (!prot_guest_has(PATTR_SEV_ES)) return; if (!sev_es_check_cpu_features()) diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index eb5cae93b238..451de8e84fce 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -383,8 +383,7 @@ static bool sme_active(void) return sme_me_mask && !sev_active(); } -/* Needs to be called from non-instrumentable code */ -bool noinstr sev_es_active(void) +static bool sev_es_active(void) { return sev_status & MSR_AMD64_SEV_ES_ENABLED; } @@ -482,7 +481,7 @@ static void print_mem_encrypt_feature_info(void) pr_cont(" SEV"); /* Encrypted Register State */ - if (sev_es_active()) + if (amd_prot_guest_has(PATTR_SEV_ES)) pr_cont(" SEV-ES"); pr_cont("\n"); @@ -501,7 +500,7 @@ void __init mem_encrypt_init(void) * With SEV, we need to unroll the rep string I/O instructions, * but SEV-ES supports them through the #VC handler. */ - if (amd_prot_guest_has(PATTR_SEV) && !sev_es_active()) + if (amd_prot_guest_has(PATTR_SEV) && !amd_prot_guest_has(PATTR_SEV_ES)) static_branch_enable(&sev_enable_key); print_mem_encrypt_feature_info(); diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index 2109ae569c67..7711d0071f41 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -2,7 +2,6 @@ #include <linux/io.h> #include <linux/slab.h> #include <linux/memblock.h> -#include <linux/mem_encrypt.h> #include <linux/protected_guest.h> #include <linux/pgtable.h> @@ -48,7 +47,7 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th) if (prot_guest_has(PATTR_HOST_MEM_ENCRYPT)) th->flags |= TH_FLAGS_SME_ACTIVE; - if (sev_es_active()) { + if (prot_guest_has(PATTR_GUEST_PROT_STATE)) { /* * Skip the call to verify_cpu() in secondary_startup_64 as it * will cause #VC exceptions when the AP can't handle them yet.
Replace occurrences of sev_es_active() with the more generic prot_guest_has() using PATTR_GUEST_PROT_STATE, except for in arch/x86/kernel/sev*.c and arch/x86/mm/mem_encrypt*.c where PATTR_SEV_ES will be used. If future support is added for other memory encyrption techonologies, the use of PATTR_GUEST_PROT_STATE can be updated, as required, to specifically use PATTR_SEV_ES. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> --- arch/x86/include/asm/mem_encrypt.h | 2 -- arch/x86/kernel/sev.c | 6 +++--- arch/x86/mm/mem_encrypt.c | 7 +++---- arch/x86/realmode/init.c | 3 +-- 4 files changed, 7 insertions(+), 11 deletions(-)