From: Joerg Roedel <jroe...@suse.de> Setup sev-es.c and include the code from the pre-decompression stage to also build it into the image of the running kernel. Temporarily add __maybe_unused annotations to avoid build warnings until the functions get used.
Signed-off-by: Joerg Roedel <jroe...@suse.de> Link: https://lore.kernel.org/r/20200724160336.5435-41-j...@8bytes.org --- arch/x86/kernel/Makefile | 1 + arch/x86/kernel/sev-es-shared.c | 21 ++-- arch/x86/kernel/sev-es.c | 163 ++++++++++++++++++++++++++++++++ 3 files changed, 175 insertions(+), 10 deletions(-) create mode 100644 arch/x86/kernel/sev-es.c diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index e77261db2391..23bc0f830f18 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -145,6 +145,7 @@ obj-$(CONFIG_UNWINDER_ORC) += unwind_orc.o obj-$(CONFIG_UNWINDER_FRAME_POINTER) += unwind_frame.o obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o +obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev-es.o ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c index a6b41910b8ab..18619279a46f 100644 --- a/arch/x86/kernel/sev-es-shared.c +++ b/arch/x86/kernel/sev-es-shared.c @@ -9,7 +9,7 @@ * and is included directly into both code-bases. */ -static void sev_es_terminate(unsigned int reason) +static void __maybe_unused sev_es_terminate(unsigned int reason) { u64 val = GHCB_SEV_TERMINATE; @@ -27,7 +27,7 @@ static void sev_es_terminate(unsigned int reason) asm volatile("hlt\n" : : : "memory"); } -static bool sev_es_negotiate_protocol(void) +static bool __maybe_unused sev_es_negotiate_protocol(void) { u64 val; @@ -46,7 +46,7 @@ static bool sev_es_negotiate_protocol(void) return true; } -static void vc_ghcb_invalidate(struct ghcb *ghcb) +static void __maybe_unused vc_ghcb_invalidate(struct ghcb *ghcb) { memset(ghcb->save.valid_bitmap, 0, sizeof(ghcb->save.valid_bitmap)); } @@ -58,9 +58,9 @@ static bool vc_decoding_needed(unsigned long exit_code) exit_code <= SVM_EXIT_LAST_EXCP); } -static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt, - struct pt_regs *regs, - unsigned long exit_code) +static enum es_result __maybe_unused vc_init_em_ctxt(struct es_em_ctxt *ctxt, + struct pt_regs *regs, + unsigned long exit_code) { enum es_result ret = ES_OK; @@ -73,7 +73,7 @@ static enum es_result vc_init_em_ctxt(struct es_em_ctxt *ctxt, return ret; } -static void vc_finish_insn(struct es_em_ctxt *ctxt) +static void __maybe_unused vc_finish_insn(struct es_em_ctxt *ctxt) { ctxt->regs->ip += ctxt->insn.length; } @@ -325,7 +325,8 @@ static enum es_result vc_ioio_exitinfo(struct es_em_ctxt *ctxt, u64 *exitinfo) return ES_OK; } -static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) +static enum es_result __maybe_unused +vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; u64 exit_info_1, exit_info_2; @@ -433,8 +434,8 @@ static enum es_result vc_handle_ioio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) return ret; } -static enum es_result vc_handle_cpuid(struct ghcb *ghcb, - struct es_em_ctxt *ctxt) +static enum es_result __maybe_unused vc_handle_cpuid(struct ghcb *ghcb, + struct es_em_ctxt *ctxt) { struct pt_regs *regs = ctxt->regs; u32 cr4 = native_read_cr4(); diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c new file mode 100644 index 000000000000..0b698b653c0b --- /dev/null +++ b/arch/x86/kernel/sev-es.c @@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Memory Encryption Support + * + * Copyright (C) 2019 SUSE + * + * Author: Joerg Roedel <jroe...@suse.de> + */ + +#include <linux/kernel.h> +#include <linux/mm.h> + +#include <asm/sev-es.h> +#include <asm/insn-eval.h> +#include <asm/fpu/internal.h> +#include <asm/processor.h> +#include <asm/trap_pf.h> +#include <asm/trapnr.h> +#include <asm/svm.h> + +static inline u64 sev_es_rd_ghcb_msr(void) +{ + return native_read_msr(MSR_AMD64_SEV_ES_GHCB); +} + +static inline void sev_es_wr_ghcb_msr(u64 val) +{ + u32 low, high; + + low = (u32)(val); + high = (u32)(val >> 32); + + native_write_msr(MSR_AMD64_SEV_ES_GHCB, low, high); +} + +static int vc_fetch_insn_kernel(struct es_em_ctxt *ctxt, + unsigned char *buffer) +{ + return copy_from_kernel_nofault(buffer, (unsigned char *)ctxt->regs->ip, MAX_INSN_SIZE); +} + +static enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) +{ + char buffer[MAX_INSN_SIZE]; + enum es_result ret; + int res; + + res = vc_fetch_insn_kernel(ctxt, buffer); + if (unlikely(res == -EFAULT)) { + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = 0; + ctxt->fi.cr2 = ctxt->regs->ip; + return ES_EXCEPTION; + } + + insn_init(&ctxt->insn, buffer, MAX_INSN_SIZE - res, 1); + insn_get_length(&ctxt->insn); + + ret = ctxt->insn.immediate.got ? ES_OK : ES_DECODE_FAILED; + + return ret; +} + +static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, + char *dst, char *buf, size_t size) +{ + unsigned long error_code = X86_PF_PROT | X86_PF_WRITE; + char __user *target = (char __user *)dst; + u64 d8; + u32 d4; + u16 d2; + u8 d1; + + switch (size) { + case 1: + memcpy(&d1, buf, 1); + if (put_user(d1, target)) + goto fault; + break; + case 2: + memcpy(&d2, buf, 2); + if (put_user(d2, target)) + goto fault; + break; + case 4: + memcpy(&d4, buf, 4); + if (put_user(d4, target)) + goto fault; + break; + case 8: + memcpy(&d8, buf, 8); + if (put_user(d8, target)) + goto fault; + break; + default: + WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size); + return ES_UNSUPPORTED; + } + + return ES_OK; + +fault: + if (user_mode(ctxt->regs)) + error_code |= X86_PF_USER; + + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = error_code; + ctxt->fi.cr2 = (unsigned long)dst; + + return ES_EXCEPTION; +} + +static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, + char *src, char *buf, size_t size) +{ + unsigned long error_code = X86_PF_PROT; + char __user *s = (char __user *)src; + u64 d8; + u32 d4; + u16 d2; + u8 d1; + + switch (size) { + case 1: + if (get_user(d1, s)) + goto fault; + memcpy(buf, &d1, 1); + break; + case 2: + if (get_user(d2, s)) + goto fault; + memcpy(buf, &d2, 2); + break; + case 4: + if (get_user(d4, s)) + goto fault; + memcpy(buf, &d4, 4); + break; + case 8: + if (get_user(d8, s)) + goto fault; + memcpy(buf, &d8, 8); + break; + default: + WARN_ONCE(1, "%s: Invalid size: %zu\n", __func__, size); + return ES_UNSUPPORTED; + } + + return ES_OK; + +fault: + if (user_mode(ctxt->regs)) + error_code |= X86_PF_USER; + + ctxt->fi.vector = X86_TRAP_PF; + ctxt->fi.error_code = error_code; + ctxt->fi.cr2 = (unsigned long)src; + + return ES_EXCEPTION; +} + +/* Include code shared with pre-decompression boot stage */ +#include "sev-es-shared.c" -- 2.28.0
