diff options
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 57968880e39b..430f950b0b7f 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -486,6 +486,8 @@ DEFINE_PER_CPU(struct cpu_entry_area *, cpu_entry_area); static inline void setup_cpu_entry_area(int cpu) { #ifdef CONFIG_X86_64 + extern char _entry_trampoline[]; + /* On 64-bit systems, we use a read-only fixmap GDT. */ pgprot_t gdt_prot = PAGE_KERNEL_RO; #else @@ -532,6 +534,11 @@ static inline void setup_cpu_entry_area(int cpu) #ifdef CONFIG_X86_32 this_cpu_write(cpu_entry_area, get_cpu_entry_area(cpu)); #endif + +#ifdef CONFIG_X86_64 + __set_fixmap(get_cpu_entry_area_index(cpu, entry_trampoline), + __pa_symbol(_entry_trampoline), PAGE_KERNEL_RX); +#endif } /* Load the original GDT from the per-cpu structure */ @@ -1395,10 +1402,16 @@ static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks /* May not be marked __init: used by software suspend */ void syscall_init(void) { + extern char _entry_trampoline[]; + extern char entry_SYSCALL_64_trampoline[]; + int cpu = smp_processor_id(); + unsigned long SYSCALL64_entry_trampoline = + (unsigned long)get_cpu_entry_area(cpu)->entry_trampoline + + (entry_SYSCALL_64_trampoline - _entry_trampoline); wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); - wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); + wrmsrl(MSR_LSTAR, SYSCALL64_entry_trampoline); #ifdef CONFIG_IA32_EMULATION wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat); |