diff options
Diffstat (limited to 'arch/x86/coco')
| -rw-r--r-- | arch/x86/coco/core.c | 10 | ||||
| -rw-r--r-- | arch/x86/coco/tdx/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/coco/tdx/tdx-shared.c | 71 | ||||
| -rw-r--r-- | arch/x86/coco/tdx/tdx.c | 171 |
4 files changed, 137 insertions, 117 deletions
diff --git a/arch/x86/coco/core.c b/arch/x86/coco/core.c index 73f83233d25d..eeec9986570e 100644 --- a/arch/x86/coco/core.c +++ b/arch/x86/coco/core.c @@ -13,10 +13,10 @@ #include <asm/coco.h> #include <asm/processor.h> -enum cc_vendor cc_vendor __ro_after_init; +enum cc_vendor cc_vendor __ro_after_init = CC_VENDOR_NONE; static u64 cc_mask __ro_after_init; -static bool intel_cc_platform_has(enum cc_attr attr) +static bool noinstr intel_cc_platform_has(enum cc_attr attr) { switch (attr) { case CC_ATTR_GUEST_UNROLL_STRING_IO: @@ -34,7 +34,7 @@ static bool intel_cc_platform_has(enum cc_attr attr) * the other levels of SME/SEV functionality, including C-bit * based SEV-SNP, are not enabled. */ -static __maybe_unused bool amd_cc_platform_vtom(enum cc_attr attr) +static __maybe_unused __always_inline bool amd_cc_platform_vtom(enum cc_attr attr) { switch (attr) { case CC_ATTR_GUEST_MEM_ENCRYPT: @@ -58,7 +58,7 @@ static __maybe_unused bool amd_cc_platform_vtom(enum cc_attr attr) * the trampoline area must be encrypted. */ -static bool amd_cc_platform_has(enum cc_attr attr) +static bool noinstr amd_cc_platform_has(enum cc_attr attr) { #ifdef CONFIG_AMD_MEM_ENCRYPT @@ -97,7 +97,7 @@ static bool amd_cc_platform_has(enum cc_attr attr) #endif } -bool cc_platform_has(enum cc_attr attr) +bool noinstr cc_platform_has(enum cc_attr attr) { switch (cc_vendor) { case CC_VENDOR_AMD: diff --git a/arch/x86/coco/tdx/Makefile b/arch/x86/coco/tdx/Makefile index 46c55998557d..2c7dcbf1458b 100644 --- a/arch/x86/coco/tdx/Makefile +++ b/arch/x86/coco/tdx/Makefile @@ -1,3 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 -obj-y += tdx.o tdcall.o +obj-y += tdx.o tdx-shared.o tdcall.o diff --git a/arch/x86/coco/tdx/tdx-shared.c b/arch/x86/coco/tdx/tdx-shared.c new file mode 100644 index 000000000000..ef20ddc37b58 --- /dev/null +++ b/arch/x86/coco/tdx/tdx-shared.c @@ -0,0 +1,71 @@ +#include <asm/tdx.h> +#include <asm/pgtable.h> + +static unsigned long try_accept_one(phys_addr_t start, unsigned long len, + enum pg_level pg_level) +{ + unsigned long accept_size = page_level_size(pg_level); + u64 tdcall_rcx; + u8 page_size; + + if (!IS_ALIGNED(start, accept_size)) + return 0; + + if (len < accept_size) + return 0; + + /* + * Pass the page physical address to the TDX module to accept the + * pending, private page. + * + * Bits 2:0 of RCX encode page size: 0 - 4K, 1 - 2M, 2 - 1G. + */ + switch (pg_level) { + case PG_LEVEL_4K: + page_size = 0; + break; + case PG_LEVEL_2M: + page_size = 1; + break; + case PG_LEVEL_1G: + page_size = 2; + break; + default: + return 0; + } + + tdcall_rcx = start | page_size; + if (__tdx_module_call(TDX_ACCEPT_PAGE, tdcall_rcx, 0, 0, 0, NULL)) + return 0; + + return accept_size; +} + +bool tdx_accept_memory(phys_addr_t start, phys_addr_t end) +{ + /* + * For shared->private conversion, accept the page using + * TDX_ACCEPT_PAGE TDX module call. + */ + while (start < end) { + unsigned long len = end - start; + unsigned long accept_size; + + /* + * Try larger accepts first. It gives chance to VMM to keep + * 1G/2M Secure EPT entries where possible and speeds up + * process by cutting number of hypercalls (if successful). + */ + + accept_size = try_accept_one(start, len, PG_LEVEL_1G); + if (!accept_size) + accept_size = try_accept_one(start, len, PG_LEVEL_2M); + if (!accept_size) + accept_size = try_accept_one(start, len, PG_LEVEL_4K); + if (!accept_size) + return false; + start += accept_size; + } + + return true; +} diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index e146b599260f..1d6b863c42b0 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -14,20 +14,6 @@ #include <asm/insn-eval.h> #include <asm/pgtable.h> -/* TDX module Call Leaf IDs */ -#define TDX_GET_INFO 1 -#define TDX_GET_VEINFO 3 -#define TDX_GET_REPORT 4 -#define TDX_ACCEPT_PAGE 6 -#define TDX_WR 8 - -/* TDCS fields. To be used by TDG.VM.WR and TDG.VM.RD module calls */ -#define TDCS_NOTIFY_ENABLES 0x9100000000000010 - -/* TDX hypercall Leaf IDs */ -#define TDVMCALL_MAP_GPA 0x10001 -#define TDVMCALL_REPORT_FATAL_ERROR 0x10003 - /* MMIO direction */ #define EPT_READ 0 #define EPT_WRITE 1 @@ -51,24 +37,6 @@ #define TDREPORT_SUBTYPE_0 0 -/* - * Wrapper for standard use of __tdx_hypercall with no output aside from - * return code. - */ -static inline u64 _tdx_hypercall(u64 fn, u64 r12, u64 r13, u64 r14, u64 r15) -{ - struct tdx_hypercall_args args = { - .r10 = TDX_HYPERCALL_STANDARD, - .r11 = fn, - .r12 = r12, - .r13 = r13, - .r14 = r14, - .r15 = r15, - }; - - return __tdx_hypercall(&args); -} - /* Called from __tdx_hypercall() for unrecoverable failure */ noinstr void __tdx_hypercall_failed(void) { @@ -76,17 +44,6 @@ noinstr void __tdx_hypercall_failed(void) panic("TDVMCALL failed. TDX module bug?"); } -/* - * The TDG.VP.VMCALL-Instruction-execution sub-functions are defined - * independently from but are currently matched 1:1 with VMX EXIT_REASONs. - * Reusing the KVM EXIT_REASON macros makes it easier to connect the host and - * guest sides of these calls. - */ -static __always_inline u64 hcall_func(u64 exit_reason) -{ - return exit_reason; -} - #ifdef CONFIG_KVM_GUEST long tdx_kvm_hypercall(unsigned int nr, unsigned long p1, unsigned long p2, unsigned long p3, unsigned long p4) @@ -745,47 +702,6 @@ static bool tdx_cache_flush_required(void) return true; } -static bool try_accept_one(phys_addr_t *start, unsigned long len, - enum pg_level pg_level) -{ - unsigned long accept_size = page_level_size(pg_level); - u64 tdcall_rcx; - u8 page_size; - - if (!IS_ALIGNED(*start, accept_size)) - return false; - - if (len < accept_size) - return false; - - /* - * Pass the page physical address to the TDX module to accept the - * pending, private page. - * - * Bits 2:0 of RCX encode page size: 0 - 4K, 1 - 2M, 2 - 1G. - */ - switch (pg_level) { - case PG_LEVEL_4K: - page_size = 0; - break; - case PG_LEVEL_2M: - page_size = 1; - break; - case PG_LEVEL_1G: - page_size = 2; - break; - default: - return false; - } - - tdcall_rcx = *start | page_size; - if (__tdx_module_call(TDX_ACCEPT_PAGE, tdcall_rcx, 0, 0, 0, NULL)) - return false; - - *start += accept_size; - return true; -} - /* * Inform the VMM of the guest's intent for this physical page: shared with * the VMM or private to the guest. The VMM is expected to change its mapping @@ -810,33 +726,34 @@ static bool tdx_enc_status_changed(unsigned long vaddr, int numpages, bool enc) if (_tdx_hypercall(TDVMCALL_MAP_GPA, start, end - start, 0, 0)) return false; - /* private->shared conversion requires only MapGPA call */ - if (!enc) - return true; + /* shared->private conversion requires memory to be accepted before use */ + if (enc) + return tdx_accept_memory(start, end); + + return true; +} +static bool tdx_enc_status_change_prepare(unsigned long vaddr, int numpages, + bool enc) +{ /* - * For shared->private conversion, accept the page using - * TDX_ACCEPT_PAGE TDX module call. + * Only handle shared->private conversion here. + * See the comment in tdx_early_init(). */ - while (start < end) { - unsigned long len = end - start; - - /* - * Try larger accepts first. It gives chance to VMM to keep - * 1G/2M SEPT entries where possible and speeds up process by - * cutting number of hypercalls (if successful). - */ - - if (try_accept_one(&start, len, PG_LEVEL_1G)) - continue; - - if (try_accept_one(&start, len, PG_LEVEL_2M)) - continue; - - if (!try_accept_one(&start, len, PG_LEVEL_4K)) - return false; - } + if (enc) + return tdx_enc_status_changed(vaddr, numpages, enc); + return true; +} +static bool tdx_enc_status_change_finish(unsigned long vaddr, int numpages, + bool enc) +{ + /* + * Only handle private->shared conversion here. + * See the comment in tdx_early_init(). + */ + if (!enc) + return tdx_enc_status_changed(vaddr, numpages, enc); return true; } @@ -852,7 +769,7 @@ void __init tdx_early_init(void) setup_force_cpu_cap(X86_FEATURE_TDX_GUEST); - cc_set_vendor(CC_VENDOR_INTEL); + cc_vendor = CC_VENDOR_INTEL; tdx_parse_tdinfo(&cc_mask); cc_set_mask(cc_mask); @@ -867,9 +784,41 @@ void __init tdx_early_init(void) */ physical_mask &= cc_mask - 1; - x86_platform.guest.enc_cache_flush_required = tdx_cache_flush_required; - x86_platform.guest.enc_tlb_flush_required = tdx_tlb_flush_required; - x86_platform.guest.enc_status_change_finish = tdx_enc_status_changed; + /* + * The kernel mapping should match the TDX metadata for the page. + * load_unaligned_zeropad() can touch memory *adjacent* to that which is + * owned by the caller and can catch even _momentary_ mismatches. Bad + * things happen on mismatch: + * + * - Private mapping => Shared Page == Guest shutdown + * - Shared mapping => Private Page == Recoverable #VE + * + * guest.enc_status_change_prepare() converts the page from + * shared=>private before the mapping becomes private. + * + * guest.enc_status_change_finish() converts the page from + * private=>shared after the mapping becomes private. + * + * In both cases there is a temporary shared mapping to a private page, + * which can result in a #VE. But, there is never a private mapping to + * a shared page. + */ + x86_platform.guest.enc_status_change_prepare = tdx_enc_status_change_prepare; + x86_platform.guest.enc_status_change_finish = tdx_enc_status_change_finish; + + x86_platform.guest.enc_cache_flush_required = tdx_cache_flush_required; + x86_platform.guest.enc_tlb_flush_required = tdx_tlb_flush_required; + + /* + * TDX intercepts the RDMSR to read the X2APIC ID in the parallel + * bringup low level code. That raises #VE which cannot be handled + * there. + * + * Intel-TDX has a secure RDMSR hypercall, but that needs to be + * implemented seperately in the low level startup ASM code. + * Until that is in place, disable parallel bringup for TDX. + */ + x86_cpuinit.parallel_bringup = false; pr_info("Guest detected\n"); } |