diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index 0d289240b6ca110ab961a280ddd20fc1c567f2a4..775cac3c02bb0a31facb970e16feef83f86c6632 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -111,6 +111,7 @@ #include extern unsigned int processor_id; +struct proc_info_list *lookup_processor(u32 midr); #ifdef CONFIG_CPU_CP15 #define read_cpuid(reg) \ diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h index e25f4392e1b2868446de858701d408aaaee26eab..e1b6f280ab088fb0b8ac59b6ceb3543606c97e01 100644 --- a/arch/arm/include/asm/proc-fns.h +++ b/arch/arm/include/asm/proc-fns.h @@ -23,7 +23,7 @@ struct mm_struct; /* * Don't change this structure - ASM code relies on it. */ -extern struct processor { +struct processor { /* MISC * get data abort address/flags */ @@ -79,9 +79,13 @@ extern struct processor { unsigned int suspend_size; void (*do_suspend)(void *); void (*do_resume)(void *); -} processor; +}; #ifndef MULTI_CPU +static inline void init_proc_vtable(const struct processor *p) +{ +} + extern void cpu_proc_init(void); extern void cpu_proc_fin(void); extern int cpu_do_idle(void); @@ -98,17 +102,50 @@ extern void cpu_reset(unsigned long addr, bool hvc) __attribute__((noreturn)); extern void cpu_do_suspend(void *); extern void cpu_do_resume(void *); #else -#define cpu_proc_init processor._proc_init -#define cpu_proc_fin processor._proc_fin -#define cpu_reset processor.reset -#define cpu_do_idle processor._do_idle -#define cpu_dcache_clean_area processor.dcache_clean_area -#define cpu_set_pte_ext processor.set_pte_ext -#define cpu_do_switch_mm processor.switch_mm -/* These three are private to arch/arm/kernel/suspend.c */ -#define cpu_do_suspend processor.do_suspend -#define cpu_do_resume processor.do_resume +extern struct processor processor; +#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) +#include +/* + * This can't be a per-cpu variable because we need to access it before + * per-cpu has been initialised. We have a couple of functions that are + * called in a pre-emptible context, and so can't use smp_processor_id() + * there, hence PROC_TABLE(). We insist in init_proc_vtable() that the + * function pointers for these are identical across all CPUs. + */ +extern struct processor *cpu_vtable[]; +#define PROC_VTABLE(f) cpu_vtable[smp_processor_id()]->f +#define PROC_TABLE(f) cpu_vtable[0]->f +static inline void init_proc_vtable(const struct processor *p) +{ + unsigned int cpu = smp_processor_id(); + *cpu_vtable[cpu] = *p; + WARN_ON_ONCE(cpu_vtable[cpu]->dcache_clean_area != + cpu_vtable[0]->dcache_clean_area); + WARN_ON_ONCE(cpu_vtable[cpu]->set_pte_ext != + cpu_vtable[0]->set_pte_ext); +} +#else +#define PROC_VTABLE(f) processor.f +#define PROC_TABLE(f) processor.f +static inline void init_proc_vtable(const struct processor *p) +{ + processor = *p; +} +#endif + +#define cpu_proc_init PROC_VTABLE(_proc_init) +#define cpu_check_bugs PROC_VTABLE(check_bugs) +#define cpu_proc_fin PROC_VTABLE(_proc_fin) +#define cpu_reset PROC_VTABLE(reset) +#define cpu_do_idle PROC_VTABLE(_do_idle) +#define cpu_dcache_clean_area PROC_TABLE(dcache_clean_area) +#define cpu_set_pte_ext PROC_TABLE(set_pte_ext) +#define cpu_do_switch_mm PROC_VTABLE(switch_mm) + +/* These two are private to arch/arm/kernel/suspend.c */ +#define cpu_do_suspend PROC_VTABLE(do_suspend) +#define cpu_do_resume PROC_VTABLE(do_resume) #endif extern void cpu_resume(void); diff --git a/arch/arm/kernel/bugs.c b/arch/arm/kernel/bugs.c index 7be5113101915cd81a5558f45238041138fb5a58..d41d3598e5e541115c08f9b81b26fd187a7fe7af 100644 --- a/arch/arm/kernel/bugs.c +++ b/arch/arm/kernel/bugs.c @@ -6,8 +6,8 @@ void check_other_bugs(void) { #ifdef MULTI_CPU - if (processor.check_bugs) - processor.check_bugs(); + if (cpu_check_bugs) + cpu_check_bugs(); #endif } diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 6e0375e7db055bc82cf0674b37b74646e2d64ff0..997b02302c3145f5ac380ae18823eba50d916ac7 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -145,6 +145,9 @@ __mmap_switched_data: #endif .size __mmap_switched_data, . - __mmap_switched_data + __FINIT + .text + /* * This provides a C-API version of __lookup_processor_type */ @@ -156,9 +159,6 @@ ENTRY(lookup_processor_type) ldmfd sp!, {r4 - r6, r9, pc} ENDPROC(lookup_processor_type) - __FINIT - .text - /* * Read processor ID register (CP#15, CR0), and look up in the linker-built * supported processor list. Note that we can't use the absolute addresses diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index ac7e08886863cfa74855e5b91c4f436e85da1e0a..375b13f7e780663eddb3f04e632751064a6b5bfd 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -114,6 +114,11 @@ EXPORT_SYMBOL(elf_hwcap2); #ifdef MULTI_CPU struct processor processor __ro_after_init; +#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) +struct processor *cpu_vtable[NR_CPUS] = { + [0] = &processor, +}; +#endif #endif #ifdef MULTI_TLB struct cpu_tlb_fns cpu_tlb __ro_after_init; @@ -666,28 +671,33 @@ static void __init smp_build_mpidr_hash(void) } #endif -static void __init setup_processor(void) +/* + * locate processor in the list of supported processor types. The linker + * builds this table for us from the entries in arch/arm/mm/proc-*.S + */ +struct proc_info_list *lookup_processor(u32 midr) { - struct proc_info_list *list; + struct proc_info_list *list = lookup_processor_type(midr); - /* - * locate processor in the list of supported processor - * types. The linker builds this table for us from the - * entries in arch/arm/mm/proc-*.S - */ - list = lookup_processor_type(read_cpuid_id()); if (!list) { - pr_err("CPU configuration botched (ID %08x), unable to continue.\n", - read_cpuid_id()); - while (1); + pr_err("CPU%u: configuration botched (ID %08x), CPU halted\n", + smp_processor_id(), midr); + while (1) + /* can't use cpu_relax() here as it may require MMU setup */; } + return list; +} + +static void __init setup_processor(void) +{ + unsigned int midr = read_cpuid_id(); + struct proc_info_list *list = lookup_processor(midr); + cpu_name = list->cpu_name; __cpu_architecture = __get_cpu_architecture(); -#ifdef MULTI_CPU - processor = *list->proc; -#endif + init_proc_vtable(list->proc); #ifdef MULTI_TLB cpu_tlb = *list->tlb; #endif @@ -699,7 +709,7 @@ static void __init setup_processor(void) #endif pr_info("CPU: %s [%08x] revision %d (ARMv%s), cr=%08lx\n", - cpu_name, read_cpuid_id(), read_cpuid_id() & 15, + list->cpu_name, midr, midr & 15, proc_arch[cpu_architecture()], get_cr()); snprintf(init_utsname()->machine, __NEW_UTS_LEN + 1, "%s%c", diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 0978282d5fc27a7c4a5e6b0e274da8bfc4c14c8d..12a6172263c0b057a94f2041accf581088374fb0 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include #include @@ -102,6 +103,30 @@ static unsigned long get_arch_pgd(pgd_t *pgd) #endif } +#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR) +static int secondary_biglittle_prepare(unsigned int cpu) +{ + if (!cpu_vtable[cpu]) + cpu_vtable[cpu] = kzalloc(sizeof(*cpu_vtable[cpu]), GFP_KERNEL); + + return cpu_vtable[cpu] ? 0 : -ENOMEM; +} + +static void secondary_biglittle_init(void) +{ + init_proc_vtable(lookup_processor(read_cpuid_id())->proc); +} +#else +static int secondary_biglittle_prepare(unsigned int cpu) +{ + return 0; +} + +static void secondary_biglittle_init(void) +{ +} +#endif + int __cpu_up(unsigned int cpu, struct task_struct *idle) { int ret; @@ -109,6 +134,10 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) if (!smp_ops.smp_boot_secondary) return -ENOSYS; + ret = secondary_biglittle_prepare(cpu); + if (ret) + return ret; + /* * We need to tell the secondary core where to find * its stack and the page tables. @@ -359,6 +388,8 @@ asmlinkage void secondary_start_kernel(void) struct mm_struct *mm = &init_mm; unsigned int cpu; + secondary_biglittle_init(); + /* * The identity mapping is uncached (strongly ordered), so * switch away from it before attempting any exclusive accesses. diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c index 5544b82a2e7a553d015e23d77a9017682dd91f11..9a07916af8dd27dd021781c06451340ce6d03032 100644 --- a/arch/arm/mm/proc-v7-bugs.c +++ b/arch/arm/mm/proc-v7-bugs.c @@ -52,8 +52,6 @@ static void cpu_v7_spectre_init(void) case ARM_CPU_PART_CORTEX_A17: case ARM_CPU_PART_CORTEX_A73: case ARM_CPU_PART_CORTEX_A75: - if (processor.switch_mm != cpu_v7_bpiall_switch_mm) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = harden_branch_predictor_bpiall; spectre_v2_method = "BPIALL"; @@ -61,8 +59,6 @@ static void cpu_v7_spectre_init(void) case ARM_CPU_PART_CORTEX_A15: case ARM_CPU_PART_BRAHMA_B15: - if (processor.switch_mm != cpu_v7_iciallu_switch_mm) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = harden_branch_predictor_iciallu; spectre_v2_method = "ICIALLU"; @@ -88,11 +84,9 @@ static void cpu_v7_spectre_init(void) ARM_SMCCC_ARCH_WORKAROUND_1, &res); if ((int)res.a0 != 0) break; - if (processor.switch_mm != cpu_v7_hvc_switch_mm && cpu) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = call_hvc_arch_workaround_1; - processor.switch_mm = cpu_v7_hvc_switch_mm; + cpu_do_switch_mm = cpu_v7_hvc_switch_mm; spectre_v2_method = "hypervisor"; break; @@ -101,11 +95,9 @@ static void cpu_v7_spectre_init(void) ARM_SMCCC_ARCH_WORKAROUND_1, &res); if ((int)res.a0 != 0) break; - if (processor.switch_mm != cpu_v7_smc_switch_mm && cpu) - goto bl_error; per_cpu(harden_branch_predictor_fn, cpu) = call_smc_arch_workaround_1; - processor.switch_mm = cpu_v7_smc_switch_mm; + cpu_do_switch_mm = cpu_v7_smc_switch_mm; spectre_v2_method = "firmware"; break; @@ -119,11 +111,6 @@ static void cpu_v7_spectre_init(void) if (spectre_v2_method) pr_info("CPU%u: Spectre v2: using %s workaround\n", smp_processor_id(), spectre_v2_method); - return; - -bl_error: - pr_err("CPU%u: Spectre v2: incorrect context switching function, system vulnerable\n", - cpu); } #else static void cpu_v7_spectre_init(void)