The following commit has been merged into the x86/cc branch of tip: Commit-ID: 6283f2effbd62a71a7c29062f8093c335ff3ea89 Gitweb: https://git.kernel.org/tip/6283f2effbd62a71a7c29062f8093c335ff3ea89 Author: Tom Lendacky <thomas.lendacky@xxxxxxx> AuthorDate: Wed, 08 Sep 2021 17:58:38 -05:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Mon, 04 Oct 2021 11:47:09 +02:00 x86/sev: Replace occurrences of sev_es_active() with cc_platform_has() Replace uses of sev_es_active() with the more generic cc_platform_has() using CC_ATTR_GUEST_STATE_ENCRYPT. If future support is added for other memory encyrption techonologies, the use of CC_ATTR_GUEST_STATE_ENCRYPT can be updated, as required. Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Link: https://lkml.kernel.org/r/20210928191009.32551-8-bp@xxxxxxxxx --- arch/x86/include/asm/mem_encrypt.h | 2 -- arch/x86/kernel/sev.c | 6 +++--- arch/x86/mm/mem_encrypt.c | 24 +++--------------------- arch/x86/realmode/init.c | 3 +-- 4 files changed, 7 insertions(+), 28 deletions(-) diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index a5a58cc..da14ede 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -51,7 +51,6 @@ 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); #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 int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; } diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index a6895e4..53a6837 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/cc_platform.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 (!cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) 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 (!cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) return; if (!sev_es_check_cpu_features()) diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 932007a..2d04c39 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -361,25 +361,6 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size) return early_set_memory_enc_dec(vaddr, size, true); } -/* - * SME and SEV are very similar but they are not the same, so there are - * times that the kernel will need to distinguish between SME and SEV. The - * cc_platform_has() function is used for this. When a distinction isn't - * needed, the CC_ATTR_MEM_ENCRYPT attribute can be used. - * - * The trampoline code is a good example for this requirement. Before - * paging is activated, SME will access all memory as decrypted, but SEV - * will access all memory as encrypted. So, when APs are being brought - * up under SME the trampoline area cannot be encrypted, whereas under SEV - * the trampoline area must be encrypted. - */ - -/* Needs to be called from non-instrumentable code */ -bool noinstr sev_es_active(void) -{ - return sev_status & MSR_AMD64_SEV_ES_ENABLED; -} - /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ bool force_dma_unencrypted(struct device *dev) { @@ -449,7 +430,7 @@ static void print_mem_encrypt_feature_info(void) pr_cont(" SEV"); /* Encrypted Register State */ - if (sev_es_active()) + if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) pr_cont(" SEV-ES"); pr_cont("\n"); @@ -468,7 +449,8 @@ 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 (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) && !sev_es_active()) + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) && + !cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) 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 c878c5e..4a3da75 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/cc_platform.h> #include <linux/pgtable.h> @@ -48,7 +47,7 @@ static void sme_sev_setup_real_mode(struct trampoline_header *th) if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) th->flags |= TH_FLAGS_SME_ACTIVE; - if (sev_es_active()) { + if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) { /* * Skip the call to verify_cpu() in secondary_startup_64 as it * will cause #VC exceptions when the AP can't handle them yet.
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