x86/sev: Move early startup code into .head.text section

[ 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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ard Biesheuvel
2024-04-19 10:11:28 +02:00
committed by Greg Kroah-Hartman
parent d6f5bc5ff0
commit f56faf87c1
4 changed files with 24 additions and 23 deletions

View File

@@ -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 */

View File

@@ -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);

View File

@@ -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;

View File

@@ -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 @@ e_term:
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 @@ fail:
*
* 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 @@ found_cc_info:
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);
}