diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-21 11:38:53 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-21 11:38:53 -0700 |
commit | 6b9bfb1365f40f14b1ad908c44dff61672c6404a (patch) | |
tree | c11c726a02de75ca3eea97d76c1bbf3394778050 /arch/x86 | |
parent | 61e2658e37b3c0c7c82aab84f4cc162e1b90f6ca (diff) | |
parent | 1e8c5971c249893ac33ca983c32bafcf5d50c727 (diff) |
Merge tag 'x86_cc_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 confidential computing updates from Borislav Petkov:
- Add shared confidential computing code which will be used by both
vendors instead of proliferating home-grown solutions for
technologies (SEV/SNP and TDX) which are pretty similar
* tag 'x86_cc_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/cpa: Generalize __set_memory_enc_pgtable()
x86/coco: Add API to handle encryption mask
x86/coco: Explicitly declare type of confidential computing platform
x86/cc: Move arch/x86/{kernel/cc_platform.c => coco/core.c}
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/Kbuild | 2 | ||||
-rw-r--r-- | arch/x86/coco/Makefile | 6 | ||||
-rw-r--r-- | arch/x86/coco/core.c (renamed from arch/x86/kernel/cc_platform.c) | 56 | ||||
-rw-r--r-- | arch/x86/include/asm/coco.h | 32 | ||||
-rw-r--r-- | arch/x86/include/asm/pgtable.h | 13 | ||||
-rw-r--r-- | arch/x86/include/asm/set_memory.h | 1 | ||||
-rw-r--r-- | arch/x86/include/asm/x86_init.h | 16 | ||||
-rw-r--r-- | arch/x86/kernel/Makefile | 5 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/mshyperv.c | 6 | ||||
-rw-r--r-- | arch/x86/kernel/x86_init.c | 16 | ||||
-rw-r--r-- | arch/x86/mm/mem_encrypt_amd.c | 72 | ||||
-rw-r--r-- | arch/x86/mm/mem_encrypt_identity.c | 12 | ||||
-rw-r--r-- | arch/x86/mm/pat/set_memory.c | 25 |
13 files changed, 199 insertions, 63 deletions
diff --git a/arch/x86/Kbuild b/arch/x86/Kbuild index f384cb1a4f7a..5a83da703e87 100644 --- a/arch/x86/Kbuild +++ b/arch/x86/Kbuild @@ -1,4 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += coco/ + obj-y += entry/ obj-$(CONFIG_PERF_EVENTS) += events/ diff --git a/arch/x86/coco/Makefile b/arch/x86/coco/Makefile new file mode 100644 index 000000000000..c1ead00017a7 --- /dev/null +++ b/arch/x86/coco/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +CFLAGS_REMOVE_core.o = -pg +KASAN_SANITIZE_core.o := n +CFLAGS_core.o += -fno-stack-protector + +obj-y += core.o diff --git a/arch/x86/kernel/cc_platform.c b/arch/x86/coco/core.c index 6a6ffcd978f6..fc1365dd927e 100644 --- a/arch/x86/kernel/cc_platform.c +++ b/arch/x86/coco/core.c @@ -9,18 +9,16 @@ #include <linux/export.h> #include <linux/cc_platform.h> -#include <linux/mem_encrypt.h> -#include <asm/mshyperv.h> +#include <asm/coco.h> #include <asm/processor.h> -static bool __maybe_unused intel_cc_platform_has(enum cc_attr attr) +static enum cc_vendor vendor __ro_after_init; +static u64 cc_mask __ro_after_init; + +static bool intel_cc_platform_has(enum cc_attr attr) { -#ifdef CONFIG_INTEL_TDX_GUEST - return false; -#else return false; -#endif } /* @@ -74,12 +72,46 @@ static bool hyperv_cc_platform_has(enum cc_attr attr) bool cc_platform_has(enum cc_attr attr) { - if (sme_me_mask) + switch (vendor) { + case CC_VENDOR_AMD: return amd_cc_platform_has(attr); - - if (hv_is_isolation_supported()) + case CC_VENDOR_INTEL: + return intel_cc_platform_has(attr); + case CC_VENDOR_HYPERV: return hyperv_cc_platform_has(attr); - - return false; + default: + return false; + } } EXPORT_SYMBOL_GPL(cc_platform_has); + +u64 cc_mkenc(u64 val) +{ + switch (vendor) { + case CC_VENDOR_AMD: + return val | cc_mask; + default: + return val; + } +} + +u64 cc_mkdec(u64 val) +{ + switch (vendor) { + case CC_VENDOR_AMD: + return val & ~cc_mask; + default: + return val; + } +} +EXPORT_SYMBOL_GPL(cc_mkdec); + +__init void cc_set_vendor(enum cc_vendor v) +{ + vendor = v; +} + +__init void cc_set_mask(u64 mask) +{ + cc_mask = mask; +} diff --git a/arch/x86/include/asm/coco.h b/arch/x86/include/asm/coco.h new file mode 100644 index 000000000000..3d98c3a60d34 --- /dev/null +++ b/arch/x86/include/asm/coco.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_COCO_H +#define _ASM_X86_COCO_H + +#include <asm/types.h> + +enum cc_vendor { + CC_VENDOR_NONE, + CC_VENDOR_AMD, + CC_VENDOR_HYPERV, + CC_VENDOR_INTEL, +}; + +void cc_set_vendor(enum cc_vendor v); +void cc_set_mask(u64 mask); + +#ifdef CONFIG_ARCH_HAS_CC_PLATFORM +u64 cc_mkenc(u64 val); +u64 cc_mkdec(u64 val); +#else +static inline u64 cc_mkenc(u64 val) +{ + return val; +} + +static inline u64 cc_mkdec(u64 val) +{ + return val; +} +#endif + +#endif /* _ASM_X86_COCO_H */ diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 8a9432fb3802..62ab07e24aef 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -15,17 +15,12 @@ cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS))) \ : (prot)) -/* - * Macros to add or remove encryption attribute - */ -#define pgprot_encrypted(prot) __pgprot(__sme_set(pgprot_val(prot))) -#define pgprot_decrypted(prot) __pgprot(__sme_clr(pgprot_val(prot))) - #ifndef __ASSEMBLY__ #include <linux/spinlock.h> #include <asm/x86_init.h> #include <asm/pkru.h> #include <asm/fpu/api.h> +#include <asm/coco.h> #include <asm-generic/pgtable_uffd.h> #include <linux/page_table_check.h> @@ -38,6 +33,12 @@ void ptdump_walk_pgd_level_debugfs(struct seq_file *m, struct mm_struct *mm, void ptdump_walk_pgd_level_checkwx(void); void ptdump_walk_user_pgd_level_checkwx(void); +/* + * Macros to add or remove encryption attribute + */ +#define pgprot_encrypted(prot) __pgprot(cc_mkenc(pgprot_val(prot))) +#define pgprot_decrypted(prot) __pgprot(cc_mkdec(pgprot_val(prot))) + #ifdef CONFIG_DEBUG_WX #define debug_checkwx() ptdump_walk_pgd_level_checkwx() #define debug_checkwx_user() ptdump_walk_user_pgd_level_checkwx() diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h index ff0f2d90338a..ce8dd215f5b3 100644 --- a/arch/x86/include/asm/set_memory.h +++ b/arch/x86/include/asm/set_memory.h @@ -84,7 +84,6 @@ int set_pages_rw(struct page *page, int numpages); int set_direct_map_invalid_noflush(struct page *page); int set_direct_map_default_noflush(struct page *page); bool kernel_page_present(struct page *page); -void notify_range_enc_status_changed(unsigned long vaddr, int npages, bool enc); extern int kernel_set_to_readonly; diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index 22b7412c08f6..e9170457697e 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -142,6 +142,21 @@ struct x86_init_acpi { }; /** + * struct x86_guest - Functions used by misc guest incarnations like SEV, TDX, etc. + * + * @enc_status_change_prepare Notify HV before the encryption status of a range is changed + * @enc_status_change_finish Notify HV after the encryption status of a range is changed + * @enc_tlb_flush_required Returns true if a TLB flush is needed before changing page encryption status + * @enc_cache_flush_required Returns true if a cache flush is needed before changing page encryption status + */ +struct x86_guest { + void (*enc_status_change_prepare)(unsigned long vaddr, int npages, bool enc); + bool (*enc_status_change_finish)(unsigned long vaddr, int npages, bool enc); + bool (*enc_tlb_flush_required)(bool enc); + bool (*enc_cache_flush_required)(void); +}; + +/** * struct x86_init_ops - functions for platform specific setup * */ @@ -287,6 +302,7 @@ struct x86_platform_ops { struct x86_legacy_features legacy; void (*set_legacy_features)(void); struct x86_hyper_runtime hyper; + struct x86_guest guest; }; struct x86_apic_ops { diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 6aef9ee28a39..6462e3dd98f4 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -21,7 +21,6 @@ CFLAGS_REMOVE_ftrace.o = -pg CFLAGS_REMOVE_early_printk.o = -pg CFLAGS_REMOVE_head64.o = -pg CFLAGS_REMOVE_sev.o = -pg -CFLAGS_REMOVE_cc_platform.o = -pg endif KASAN_SANITIZE_head$(BITS).o := n @@ -30,7 +29,6 @@ KASAN_SANITIZE_dumpstack_$(BITS).o := n KASAN_SANITIZE_stacktrace.o := n KASAN_SANITIZE_paravirt.o := n KASAN_SANITIZE_sev.o := n -KASAN_SANITIZE_cc_platform.o := n # With some compiler versions the generated code results in boot hangs, caused # by several compilation units. To be safe, disable all instrumentation. @@ -49,7 +47,6 @@ endif KCOV_INSTRUMENT := n CFLAGS_head$(BITS).o += -fno-stack-protector -CFLAGS_cc_platform.o += -fno-stack-protector CFLAGS_irq.o := -I $(srctree)/$(src)/../include/asm/trace @@ -151,8 +148,6 @@ obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev.o -obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += cc_platform.o - ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 5a99f993e639..e0a572472052 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -33,6 +33,7 @@ #include <asm/nmi.h> #include <clocksource/hyperv_timer.h> #include <asm/numa.h> +#include <asm/coco.h> /* Is Linux running as the root partition? */ bool hv_root_partition; @@ -344,6 +345,11 @@ static void __init ms_hyperv_init_platform(void) */ swiotlb_force = SWIOTLB_FORCE; #endif + /* Isolation VMs are unenlightened SEV-based VMs, thus this check: */ + if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) { + if (hv_get_isolation_type() != HV_ISOLATION_TYPE_NONE) + cc_set_vendor(CC_VENDOR_HYPERV); + } } if (hv_max_functions_eax >= HYPERV_CPUID_NESTED_FEATURES) { diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c index 7d20c1d34a3c..e84ee5cdbd8c 100644 --- a/arch/x86/kernel/x86_init.c +++ b/arch/x86/kernel/x86_init.c @@ -129,6 +129,11 @@ struct x86_cpuinit_ops x86_cpuinit = { static void default_nmi_init(void) { }; +static void enc_status_change_prepare_noop(unsigned long vaddr, int npages, bool enc) { } +static bool enc_status_change_finish_noop(unsigned long vaddr, int npages, bool enc) { return false; } +static bool enc_tlb_flush_required_noop(bool enc) { return false; } +static bool enc_cache_flush_required_noop(void) { return false; } + struct x86_platform_ops x86_platform __ro_after_init = { .calibrate_cpu = native_calibrate_cpu_early, .calibrate_tsc = native_calibrate_tsc, @@ -138,9 +143,16 @@ struct x86_platform_ops x86_platform __ro_after_init = { .is_untracked_pat_range = is_ISA_range, .nmi_init = default_nmi_init, .get_nmi_reason = default_get_nmi_reason, - .save_sched_clock_state = tsc_save_sched_clock_state, - .restore_sched_clock_state = tsc_restore_sched_clock_state, + .save_sched_clock_state = tsc_save_sched_clock_state, + .restore_sched_clock_state = tsc_restore_sched_clock_state, .hyper.pin_vcpu = x86_op_int_noop, + + .guest = { + .enc_status_change_prepare = enc_status_change_prepare_noop, + .enc_status_change_finish = enc_status_change_finish_noop, + .enc_tlb_flush_required = enc_tlb_flush_required_noop, + .enc_cache_flush_required = enc_cache_flush_required_noop, + }, }; EXPORT_SYMBOL_GPL(x86_platform); diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c index 2b2d018ea345..6169053c2854 100644 --- a/arch/x86/mm/mem_encrypt_amd.c +++ b/arch/x86/mm/mem_encrypt_amd.c @@ -177,25 +177,6 @@ void __init sme_map_bootdata(char *real_mode_data) __sme_early_map_unmap_mem(__va(cmdline_paddr), COMMAND_LINE_SIZE, true); } -void __init sme_early_init(void) -{ - unsigned int i; - - if (!sme_me_mask) - return; - - early_pmd_flags = __sme_set(early_pmd_flags); - - __supported_pte_mask = __sme_set(__supported_pte_mask); - - /* Update the protection map with memory encryption mask */ - for (i = 0; i < ARRAY_SIZE(protection_map); i++) - protection_map[i] = pgprot_encrypted(protection_map[i]); - - if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) - swiotlb_force = SWIOTLB_FORCE; -} - void __init sev_setup_arch(void) { phys_addr_t total_mem = memblock_phys_mem_size(); @@ -256,7 +237,17 @@ static unsigned long pg_level_to_pfn(int level, pte_t *kpte, pgprot_t *ret_prot) return pfn; } -void notify_range_enc_status_changed(unsigned long vaddr, int npages, bool enc) +static bool amd_enc_tlb_flush_required(bool enc) +{ + return true; +} + +static bool amd_enc_cache_flush_required(void) +{ + return !cpu_feature_enabled(X86_FEATURE_SME_COHERENT); +} + +static void enc_dec_hypercall(unsigned long vaddr, int npages, bool enc) { #ifdef CONFIG_PARAVIRT unsigned long sz = npages << PAGE_SHIFT; @@ -287,6 +278,19 @@ void notify_range_enc_status_changed(unsigned long vaddr, int npages, bool enc) #endif } +static void amd_enc_status_change_prepare(unsigned long vaddr, int npages, bool enc) +{ +} + +/* Return true unconditionally: return value doesn't matter for the SEV side */ +static bool amd_enc_status_change_finish(unsigned long vaddr, int npages, bool enc) +{ + if (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) + enc_dec_hypercall(vaddr, npages, enc); + + return true; +} + static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) { pgprot_t old_prot, new_prot; @@ -392,7 +396,7 @@ static int __init early_set_memory_enc_dec(unsigned long vaddr, ret = 0; - notify_range_enc_status_changed(start, PAGE_ALIGN(size) >> PAGE_SHIFT, enc); + early_set_mem_enc_dec_hypercall(start, PAGE_ALIGN(size) >> PAGE_SHIFT, enc); out: __flush_tlb_all(); return ret; @@ -410,7 +414,31 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size) void __init early_set_mem_enc_dec_hypercall(unsigned long vaddr, int npages, bool enc) { - notify_range_enc_status_changed(vaddr, npages, enc); + enc_dec_hypercall(vaddr, npages, enc); +} + +void __init sme_early_init(void) +{ + unsigned int i; + + if (!sme_me_mask) + return; + + early_pmd_flags = __sme_set(early_pmd_flags); + + __supported_pte_mask = __sme_set(__supported_pte_mask); + + /* Update the protection map with memory encryption mask */ + for (i = 0; i < ARRAY_SIZE(protection_map); i++) + protection_map[i] = pgprot_encrypted(protection_map[i]); + + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) + swiotlb_force = SWIOTLB_FORCE; + + x86_platform.guest.enc_status_change_prepare = amd_enc_status_change_prepare; + x86_platform.guest.enc_status_change_finish = amd_enc_status_change_finish; + x86_platform.guest.enc_tlb_flush_required = amd_enc_tlb_flush_required; + x86_platform.guest.enc_cache_flush_required = amd_enc_cache_flush_required; } void __init mem_encrypt_free_decrypted_mem(void) diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c index 3f0abb403340..b43bc24d2bb6 100644 --- a/arch/x86/mm/mem_encrypt_identity.c +++ b/arch/x86/mm/mem_encrypt_identity.c @@ -44,6 +44,7 @@ #include <asm/setup.h> #include <asm/sections.h> #include <asm/cmdline.h> +#include <asm/coco.h> #include "mm_internal.h" @@ -565,8 +566,7 @@ void __init sme_enable(struct boot_params *bp) } else { /* SEV state cannot be controlled by a command line option */ sme_me_mask = me_mask; - physical_mask &= ~sme_me_mask; - return; + goto out; } /* @@ -600,6 +600,10 @@ void __init sme_enable(struct boot_params *bp) sme_me_mask = 0; else sme_me_mask = active_by_default ? me_mask : 0; - - physical_mask &= ~sme_me_mask; +out: + if (sme_me_mask) { + physical_mask &= ~sme_me_mask; + cc_set_vendor(CC_VENDOR_AMD); + cc_set_mask(sme_me_mask); + } } diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index b4072115c8ef..3b75262cfb27 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1989,6 +1989,7 @@ int set_memory_global(unsigned long addr, int numpages) */ static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc) { + pgprot_t empty = __pgprot(0); struct cpa_data cpa; int ret; @@ -1999,18 +2000,20 @@ static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc) memset(&cpa, 0, sizeof(cpa)); cpa.vaddr = &addr; cpa.numpages = numpages; - cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0); - cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC); + cpa.mask_set = enc ? pgprot_encrypted(empty) : pgprot_decrypted(empty); + cpa.mask_clr = enc ? pgprot_decrypted(empty) : pgprot_encrypted(empty); cpa.pgd = init_mm.pgd; /* Must avoid aliasing mappings in the highmem code */ kmap_flush_unused(); vm_unmap_aliases(); - /* - * Before changing the encryption attribute, we need to flush caches. - */ - cpa_flush(&cpa, !this_cpu_has(X86_FEATURE_SME_COHERENT)); + /* Flush the caches as needed before changing the encryption attribute. */ + if (x86_platform.guest.enc_tlb_flush_required(enc)) + cpa_flush(&cpa, x86_platform.guest.enc_cache_flush_required()); + + /* Notify hypervisor that we are about to set/clr encryption attribute. */ + x86_platform.guest.enc_status_change_prepare(addr, numpages, enc); ret = __change_page_attr_set_clr(&cpa, 1); @@ -2023,11 +2026,11 @@ static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc) */ cpa_flush(&cpa, 0); - /* - * Notify hypervisor that a given memory range is mapped encrypted - * or decrypted. - */ - notify_range_enc_status_changed(addr, numpages, enc); + /* Notify hypervisor that we have successfully set/clr encryption attribute. */ + if (!ret) { + if (!x86_platform.guest.enc_status_change_finish(addr, numpages, enc)) + ret = -EIO; + } return ret; } |