The following commit has been merged into the x86/sev branch of tip: Commit-ID: 58f3e6b71f42f99ab5d0ab26ddf6e7ee5631f5db Gitweb: https://git.kernel.org/tip/58f3e6b71f42f99ab5d0ab26ddf6e7ee5631f5db Author: Michael Roth <michael.roth@xxxxxxx> AuthorDate: Thu, 24 Feb 2022 10:56:05 -06:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Wed, 06 Apr 2022 17:07:09 +02:00 x86/compressed/acpi: Move EFI system table lookup to helper Future patches for SEV-SNP-validated CPUID will also require early parsing of the EFI configuration. Incrementally move the related code into a set of helpers that can be re-used for that purpose. Signed-off-by: Michael Roth <michael.roth@xxxxxxx> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Link: https://lore.kernel.org/r/20220307213356.2797205-26-brijesh.singh@xxxxxxx --- arch/x86/boot/compressed/acpi.c | 21 +++++++-------------- arch/x86/boot/compressed/efi.c | 29 +++++++++++++++++++++++++++++ arch/x86/boot/compressed/misc.h | 6 ++++++ 3 files changed, 42 insertions(+), 14 deletions(-) diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c index db6c561..58a3d3f 100644 --- a/arch/x86/boot/compressed/acpi.c +++ b/arch/x86/boot/compressed/acpi.c @@ -105,7 +105,7 @@ static acpi_physical_address kexec_get_rsdp_addr(void) } /* Get systab from boot params. */ - systab = (efi_system_table_64_t *) (ei->efi_systab | ((__u64)ei->efi_systab_hi << 32)); + systab = (efi_system_table_64_t *)efi_get_system_table(boot_params); if (!systab) error("EFI system table not found in kexec boot_params."); @@ -118,9 +118,8 @@ static acpi_physical_address kexec_get_rsdp_addr(void) { return 0; } static acpi_physical_address efi_get_rsdp_addr(void) { #ifdef CONFIG_EFI - unsigned long systab, config_tables; + unsigned long systab_pa, config_tables; unsigned int nr_tables; - struct efi_info *ei; enum efi_type et; bool efi_64; @@ -132,24 +131,18 @@ static acpi_physical_address efi_get_rsdp_addr(void) else return 0; - /* Get systab from boot params. */ - ei = &boot_params->efi_info; -#ifdef CONFIG_X86_64 - systab = ei->efi_systab | ((__u64)ei->efi_systab_hi << 32); -#else - systab = ei->efi_systab; -#endif - if (!systab) - error("EFI system table not found."); + systab_pa = efi_get_system_table(boot_params); + if (!systab_pa) + error("EFI support advertised, but unable to locate system table."); /* Handle EFI bitness properly */ if (efi_64) { - efi_system_table_64_t *stbl = (efi_system_table_64_t *)systab; + efi_system_table_64_t *stbl = (efi_system_table_64_t *)systab_pa; config_tables = stbl->tables; nr_tables = stbl->nr_tables; } else { - efi_system_table_32_t *stbl = (efi_system_table_32_t *)systab; + efi_system_table_32_t *stbl = (efi_system_table_32_t *)systab_pa; config_tables = stbl->tables; nr_tables = stbl->nr_tables; diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c index bad0ce3..72a81ba 100644 --- a/arch/x86/boot/compressed/efi.c +++ b/arch/x86/boot/compressed/efi.c @@ -48,3 +48,32 @@ enum efi_type efi_get_type(struct boot_params *bp) return et; } + +/** + * efi_get_system_table - Given a pointer to boot_params, retrieve the physical address + * of the EFI system table. + * + * @bp: pointer to boot_params + * + * Return: EFI system table address on success. On error, return 0. + */ +unsigned long efi_get_system_table(struct boot_params *bp) +{ + unsigned long sys_tbl_pa; + struct efi_info *ei; + enum efi_type et; + + /* Get systab from boot params. */ + ei = &bp->efi_info; +#ifdef CONFIG_X86_64 + sys_tbl_pa = ei->efi_systab | ((__u64)ei->efi_systab_hi << 32); +#else + sys_tbl_pa = ei->efi_systab; +#endif + if (!sys_tbl_pa) { + debug_putstr("EFI system table not found."); + return 0; + } + + return sys_tbl_pa; +} diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index fede1af..b2acd3a 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -185,11 +185,17 @@ enum efi_type { #ifdef CONFIG_EFI /* helpers for early EFI config table access */ enum efi_type efi_get_type(struct boot_params *bp); +unsigned long efi_get_system_table(struct boot_params *bp); #else static inline enum efi_type efi_get_type(struct boot_params *bp) { return EFI_TYPE_NONE; } + +static inline unsigned long efi_get_system_table(struct boot_params *bp) +{ + return 0; +} #endif /* CONFIG_EFI */ #endif /* BOOT_COMPRESSED_MISC_H */
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