From: Ard Biesheuvel ardb@kernel.org
[ Commit 428080c9b19bfda37c478cd626dbd3851db1aff9 upstream ]
In preparation for implementing rigorous build time checks to enforce that only code that can support it will be called from the early 1:1 mapping of memory, move SEV init code that is called in this manner to the .head.text section.
Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Tested-by: Tom Lendacky thomas.lendacky@amd.com Link: https://lore.kernel.org/r/20240227151907.387873-19-ardb+git@google.com Signed-off-by: Ard Biesheuvel ardb@kernel.org --- arch/x86/boot/compressed/sev.c | 3 +++ arch/x86/include/asm/sev.h | 10 ++++----- arch/x86/kernel/sev-shared.c | 23 +++++++++----------- arch/x86/kernel/sev.c | 11 +++++----- 4 files changed, 24 insertions(+), 23 deletions(-)
diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c index d07e665bb265..3c5d5c97f8f7 100644 --- a/arch/x86/boot/compressed/sev.c +++ b/arch/x86/boot/compressed/sev.c @@ -118,6 +118,9 @@ static bool fault_in_kernel_space(unsigned long address) #define __init #define __pa(x) ((unsigned long)(x))
+#undef __head +#define __head + #define __BOOT_COMPRESSED
/* Basic instruction decoding support needed */ diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h index c57dd21155bd..bcac2e53d50b 100644 --- a/arch/x86/include/asm/sev.h +++ b/arch/x86/include/asm/sev.h @@ -192,15 +192,15 @@ static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate) struct snp_guest_request_ioctl;
void setup_ghcb(void); -void __init early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, - unsigned long npages); -void __init early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, - unsigned long npages); +void early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, + unsigned long npages); +void early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, + unsigned long npages); void snp_set_memory_shared(unsigned long vaddr, unsigned long npages); void snp_set_memory_private(unsigned long vaddr, unsigned long npages); void snp_set_wakeup_secondary_cpu(void); bool snp_init(struct boot_params *bp); -void __init __noreturn snp_abort(void); +void __noreturn snp_abort(void); void snp_dmi_setup(void); int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio); u64 snp_get_unsupported_features(u64 status); diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c index 271e70d5748e..3fe76bf17d95 100644 --- a/arch/x86/kernel/sev-shared.c +++ b/arch/x86/kernel/sev-shared.c @@ -86,7 +86,8 @@ static bool __init sev_es_check_cpu_features(void) return true; }
-static void __noreturn sev_es_terminate(unsigned int set, unsigned int reason) +static void __head __noreturn +sev_es_terminate(unsigned int set, unsigned int reason) { u64 val = GHCB_MSR_TERM_REQ;
@@ -323,13 +324,7 @@ static int sev_cpuid_hv(struct ghcb *ghcb, struct es_em_ctxt *ctxt, struct cpuid */ static const struct snp_cpuid_table *snp_cpuid_get_table(void) { - void *ptr; - - asm ("lea cpuid_table_copy(%%rip), %0" - : "=r" (ptr) - : "p" (&cpuid_table_copy)); - - return ptr; + return &RIP_REL_REF(cpuid_table_copy); }
/* @@ -388,7 +383,7 @@ static u32 snp_cpuid_calc_xsave_size(u64 xfeatures_en, bool compacted) return xsave_size; }
-static bool +static bool __head snp_cpuid_get_validated_func(struct cpuid_leaf *leaf) { const struct snp_cpuid_table *cpuid_table = snp_cpuid_get_table(); @@ -525,7 +520,8 @@ static int snp_cpuid_postprocess(struct ghcb *ghcb, struct es_em_ctxt *ctxt, * Returns -EOPNOTSUPP if feature not enabled. Any other non-zero return value * should be treated as fatal by caller. */ -static int snp_cpuid(struct ghcb *ghcb, struct es_em_ctxt *ctxt, struct cpuid_leaf *leaf) +static int __head +snp_cpuid(struct ghcb *ghcb, struct es_em_ctxt *ctxt, struct cpuid_leaf *leaf) { const struct snp_cpuid_table *cpuid_table = snp_cpuid_get_table();
@@ -567,7 +563,7 @@ static int snp_cpuid(struct ghcb *ghcb, struct es_em_ctxt *ctxt, struct cpuid_le * page yet, so it only supports the MSR based communication with the * hypervisor and only the CPUID exit-code. */ -void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code) +void __head do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code) { unsigned int subfn = lower_bits(regs->cx, 32); unsigned int fn = lower_bits(regs->ax, 32); @@ -1013,7 +1009,8 @@ struct cc_setup_data { * Search for a Confidential Computing blob passed in as a setup_data entry * via the Linux Boot Protocol. */ -static struct cc_blob_sev_info *find_cc_blob_setup_data(struct boot_params *bp) +static __head +struct cc_blob_sev_info *find_cc_blob_setup_data(struct boot_params *bp) { struct cc_setup_data *sd = NULL; struct setup_data *hdr; @@ -1040,7 +1037,7 @@ static struct cc_blob_sev_info *find_cc_blob_setup_data(struct boot_params *bp) * mapping needs to be updated in sync with all the changes to virtual memory * layout and related mapping facilities throughout the boot process. */ -static void __init setup_cpuid_table(const struct cc_blob_sev_info *cc_info) +static void __head setup_cpuid_table(const struct cc_blob_sev_info *cc_info) { const struct snp_cpuid_table *cpuid_table_fw, *cpuid_table; int i; diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index e35fcc8d4bae..f8a8249ae117 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -26,6 +26,7 @@ #include <linux/dmi.h> #include <uapi/linux/sev-guest.h>
+#include <asm/init.h> #include <asm/cpu_entry_area.h> #include <asm/stacktrace.h> #include <asm/sev.h> @@ -690,7 +691,7 @@ static void pvalidate_pages(unsigned long vaddr, unsigned long npages, bool vali } }
-static void __init early_set_pages_state(unsigned long paddr, unsigned long npages, enum psc_op op) +static void __head early_set_pages_state(unsigned long paddr, unsigned long npages, enum psc_op op) { unsigned long paddr_end; u64 val; @@ -728,7 +729,7 @@ static void __init early_set_pages_state(unsigned long paddr, unsigned long npag sev_es_terminate(SEV_TERM_SET_LINUX, GHCB_TERM_PSC); }
-void __init early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, +void __head early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { /* @@ -2085,7 +2086,7 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs) * * Scan for the blob in that order. */ -static __init struct cc_blob_sev_info *find_cc_blob(struct boot_params *bp) +static __head struct cc_blob_sev_info *find_cc_blob(struct boot_params *bp) { struct cc_blob_sev_info *cc_info;
@@ -2111,7 +2112,7 @@ static __init struct cc_blob_sev_info *find_cc_blob(struct boot_params *bp) return cc_info; }
-bool __init snp_init(struct boot_params *bp) +bool __head snp_init(struct boot_params *bp) { struct cc_blob_sev_info *cc_info;
@@ -2133,7 +2134,7 @@ bool __init snp_init(struct boot_params *bp) return true; }
-void __init __noreturn snp_abort(void) +void __head __noreturn snp_abort(void) { sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SNP_UNSUPPORTED); }