diff options
| author | Jarkko Sakkinen <jarkko.sakkinen@intel.com> | 2012-05-08 20:22:46 +0200 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-05-09 00:04:27 +0200 |
| commit | cda846f101fb1396b6924f1d9b68ac3d42de5403 (patch) | |
| tree | 1fa8716c308b8e10156a1caf51d8ff6c98eceea9 /arch/x86/kernel | |
| parent | x86, realmode: fixes compilation issue in tboot.c (diff) | |
| download | linux-cda846f101fb1396b6924f1d9b68ac3d42de5403.tar.xz linux-cda846f101fb1396b6924f1d9b68ac3d42de5403.zip | |
x86, realmode: read cr4 and EFER from kernel for 64-bit trampoline
This patch changes 64-bit trampoline so that CR4 and
EFER are provided by the kernel instead of using fixed
values.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-24-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/realmode.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 2 |
2 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/kernel/realmode.c b/arch/x86/kernel/realmode.c index 712fba8fd774..66ac276cf361 100644 --- a/arch/x86/kernel/realmode.c +++ b/arch/x86/kernel/realmode.c @@ -6,6 +6,7 @@ #include <asm/realmode.h> struct real_mode_header *real_mode_header; +u32 *trampoline_cr4_features; void __init setup_real_mode(void) { @@ -64,7 +65,14 @@ void __init setup_real_mode(void) trampoline_header->gdt_limit = __BOOT_DS + 7; trampoline_header->gdt_base = __pa(boot_gdt); #else + if (rdmsr_safe(MSR_EFER, &trampoline_header->efer_low, + &trampoline_header->efer_high)) + BUG(); + trampoline_header->start = (u64) secondary_startup_64; + trampoline_cr4_features = &trampoline_header->cr4; + *trampoline_cr4_features = read_cr4(); + trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd); trampoline_pgd[0] = __pa(level3_ident_pgt) + _KERNPG_TABLE; trampoline_pgd[511] = __pa(level3_kernel_pgt) + _KERNPG_TABLE; diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 7a14fece9cfc..efcf305210a4 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -975,6 +975,8 @@ void __init setup_arch(char **cmdline_p) if (boot_cpu_data.cpuid_level >= 0) { /* A CPU has %cr4 if and only if it has CPUID */ mmu_cr4_features = read_cr4(); + if (trampoline_cr4_features) + *trampoline_cr4_features = mmu_cr4_features; } #ifdef CONFIG_X86_32 |