diff options
Diffstat (limited to 'arch/x86/boot/compressed/pgtable_64.c')
| -rw-r--r-- | arch/x86/boot/compressed/pgtable_64.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index a362fa0b849c..8c5107545251 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -31,16 +31,23 @@ static char trampoline_save[TRAMPOLINE_32BIT_SIZE]; */ unsigned long *trampoline_32bit __section(.data); -struct paging_config paging_prepare(void) +extern struct boot_params *boot_params; +int cmdline_find_option_bool(const char *option); + +struct paging_config paging_prepare(void *rmode) { struct paging_config paging_config = {}; unsigned long bios_start, ebda_start; + /* Initialize boot_params. Required for cmdline_find_option_bool(). */ + boot_params = rmode; + /* * Check if LA57 is desired and supported. * - * There are two parts to the check: + * There are several parts to the check: * - if the kernel supports 5-level paging: CONFIG_X86_5LEVEL=y + * - if user asked to disable 5-level paging: no5lvl in cmdline * - if the machine supports 5-level paging: * + CPUID leaf 7 is supported * + the leaf has the feature bit set @@ -48,6 +55,7 @@ struct paging_config paging_prepare(void) * That's substitute for boot_cpu_has() in early boot code. */ if (IS_ENABLED(CONFIG_X86_5LEVEL) && + !cmdline_find_option_bool("no5lvl") && native_cpuid_eax(0) >= 7 && (native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) { paging_config.l5_required = 1; @@ -130,7 +138,7 @@ void cleanup_trampoline(void *pgtable) { void *trampoline_pgtable; - trampoline_pgtable = trampoline_32bit + TRAMPOLINE_32BIT_PGTABLE_OFFSET; + trampoline_pgtable = trampoline_32bit + TRAMPOLINE_32BIT_PGTABLE_OFFSET / sizeof(unsigned long); /* * Move the top level page table out of trampoline memory, |