diff options
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 40 |
1 files changed, 24 insertions, 16 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index a1b756c49a93..a99d00393206 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1773,10 +1773,16 @@ void syscall_init(void) wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); #endif - /* Flags to clear on syscall */ + /* + * Flags to clear on syscall; clear as much as possible + * to minimize user space-kernel interference. + */ wrmsrl(MSR_SYSCALL_MASK, - X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF| - X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT); + X86_EFLAGS_CF|X86_EFLAGS_PF|X86_EFLAGS_AF| + X86_EFLAGS_ZF|X86_EFLAGS_SF|X86_EFLAGS_TF| + X86_EFLAGS_IF|X86_EFLAGS_DF|X86_EFLAGS_OF| + X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_RF| + X86_EFLAGS_AC|X86_EFLAGS_ID); } #else /* CONFIG_X86_64 */ @@ -1938,13 +1944,12 @@ void cpu_init_exception_handling(void) /* * cpu_init() initializes state that is per-CPU. Some data is already - * initialized (naturally) in the bootstrap process, such as the GDT - * and IDT. We reload them nevertheless, this function acts as a - * 'CPU state barrier', nothing should get across. + * initialized (naturally) in the bootstrap process, such as the GDT. We + * reload it nevertheless, this function acts as a 'CPU state barrier', + * nothing should get across. */ void cpu_init(void) { - struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw); struct task_struct *cur = current; int cpu = raw_smp_processor_id(); @@ -1957,8 +1962,6 @@ void cpu_init(void) early_cpu_to_node(cpu) != NUMA_NO_NODE) set_numa_node(early_cpu_to_node(cpu)); #endif - setup_getcpu(cpu); - pr_debug("Initializing CPU#%d\n", cpu); if (IS_ENABLED(CONFIG_X86_64) || cpu_feature_enabled(X86_FEATURE_VME) || @@ -1970,7 +1973,6 @@ void cpu_init(void) * and set up the GDT descriptor: */ switch_to_new_gdt(cpu); - load_current_idt(); if (IS_ENABLED(CONFIG_X86_64)) { loadsegment(fs, 0); @@ -1990,12 +1992,6 @@ void cpu_init(void) initialize_tlbstate_and_flush(); enter_lazy_tlb(&init_mm, cur); - /* Initialize the TSS. */ - tss_setup_ist(tss); - tss_setup_io_bitmap(tss); - set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss); - - load_TR_desc(); /* * sp0 points to the entry trampoline stack regardless of what task * is running. @@ -2017,6 +2013,18 @@ void cpu_init(void) load_fixmap_gdt(cpu); } +#ifdef CONFIG_SMP +void cpu_init_secondary(void) +{ + /* + * Relies on the BP having set-up the IDT tables, which are loaded + * on this CPU in cpu_init_exception_handling(). + */ + cpu_init_exception_handling(); + cpu_init(); +} +#endif + /* * The microcode loader calls this upon late microcode load to recheck features, * only when microcode has been updated. Caller holds microcode_mutex and CPU |