diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/asm-offsets.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 15 | ||||
| -rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 9 |
3 files changed, 24 insertions, 1 deletions
diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c index 55858b277cf6..61b1af88ac07 100644 --- a/arch/x86/kernel/asm-offsets.c +++ b/arch/x86/kernel/asm-offsets.c @@ -101,4 +101,5 @@ void common(void) { /* Layout info for cpu_entry_area */ OFFSET(CPU_ENTRY_AREA_tss, cpu_entry_area, tss); + OFFSET(CPU_ENTRY_AREA_entry_trampoline, cpu_entry_area, entry_trampoline); } 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); diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index a4009fb9be87..d2a8b5a24a44 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -107,6 +107,15 @@ SECTIONS SOFTIRQENTRY_TEXT *(.fixup) *(.gnu.warning) + +#ifdef CONFIG_X86_64 + . = ALIGN(PAGE_SIZE); + _entry_trampoline = .; + *(.entry_trampoline) + . = ALIGN(PAGE_SIZE); + ASSERT(. - _entry_trampoline == PAGE_SIZE, "entry trampoline is too big"); +#endif + /* End of text section */ _etext = .; } :text = 0x9090 |