diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 5ad2151c43dd..50ae5286f59b 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -127,8 +127,8 @@ config ARM select PERF_USE_VMALLOC select RTC_LIB select SYS_SUPPORTS_APM_EMULATION - select THREAD_INFO_IN_TASK if CURRENT_POINTER_IN_TPIDRURO - select HAVE_ARCH_VMAP_STACK if MMU && THREAD_INFO_IN_TASK && (!LD_IS_LLD || LLD_VERSION >= 140000) + select THREAD_INFO_IN_TASK + select HAVE_ARCH_VMAP_STACK if MMU && (!LD_IS_LLD || LLD_VERSION >= 140000) select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M # Above selects are sorted alphabetically; please add new ones # according to that. Thanks. @@ -1158,7 +1158,7 @@ config CURRENT_POINTER_IN_TPIDRURO config IRQSTACKS def_bool y - depends on THREAD_INFO_IN_TASK + depends on MMU select HAVE_IRQ_EXIT_ON_IRQ_STACK select HAVE_SOFTIRQ_ON_OWN_STACK @@ -1608,7 +1608,7 @@ config CC_HAVE_STACKPROTECTOR_TLS config STACKPROTECTOR_PER_TASK bool "Use a unique stack canary value for each task" - depends on STACKPROTECTOR && THREAD_INFO_IN_TASK && !XIP_DEFLATED_DATA + depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS default y diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index f9b3dd0e9ef5..59d7b9e81934 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -203,41 +203,12 @@ THUMB( fpreg .req r7 ) .endm .endr - .macro get_current, rd -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO - mrc p15, 0, \rd, c13, c0, 3 @ get TPIDRURO register -#else - get_thread_info \rd - ldr \rd, [\rd, #TI_TASK] -#endif - .endm - - .macro set_current, rn -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO - mcr p15, 0, \rn, c13, c0, 3 @ set TPIDRURO register -#endif - .endm - - .macro reload_current, t1:req, t2:req -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO - ldr_this_cpu \t1, __entry_task, \t1, \t2 - mcr p15, 0, \t1, c13, c0, 3 @ store in TPIDRURO -#endif - .endm - /* * Get current thread_info. */ .macro get_thread_info, rd -#ifdef CONFIG_THREAD_INFO_IN_TASK /* thread_info is the first member of struct task_struct */ get_current \rd -#else - ARM( mov \rd, sp, lsr #THREAD_SIZE_ORDER + PAGE_SHIFT ) - THUMB( mov \rd, sp ) - THUMB( lsr \rd, \rd, #THREAD_SIZE_ORDER + PAGE_SHIFT ) - mov \rd, \rd, lsl #THREAD_SIZE_ORDER + PAGE_SHIFT -#endif .endm /* @@ -330,6 +301,60 @@ ALT_UP_B(.L1_\@) #endif .endm + /* + * set_current - store the task pointer of this CPU's current task + */ + .macro set_current, rn:req, tmp:req +#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP) +9998: mcr p15, 0, \rn, c13, c0, 3 @ set TPIDRURO register +#ifdef CONFIG_CPU_V6 +ALT_UP_B(.L0_\@) + .subsection 1 +.L0_\@: str_va \rn, __current, \tmp + b .L1_\@ + .previous +.L1_\@: +#endif +#else + str_va \rn, __current, \tmp +#endif + .endm + + /* + * get_current - load the task pointer of this CPU's current task + */ + .macro get_current, rd:req +#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP) +9998: mrc p15, 0, \rd, c13, c0, 3 @ get TPIDRURO register +#ifdef CONFIG_CPU_V6 +ALT_UP_B(.L0_\@) + .subsection 1 +.L0_\@: ldr_va \rd, __current + b .L1_\@ + .previous +.L1_\@: +#endif +#else + ldr_va \rd, __current +#endif + .endm + + /* + * reload_current - reload the task pointer of this CPU's current task + * into the TLS register + */ + .macro reload_current, t1:req, t2:req +#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP) +#ifdef CONFIG_CPU_V6 +ALT_SMP(nop) +ALT_UP_B(.L0_\@) +#endif + ldr_this_cpu \t1, __entry_task, \t1, \t2 + mcr p15, 0, \t1, c13, c0, 3 @ store in TPIDRURO +.L0_\@: +#endif + .endm + /* * Instruction barrier */ diff --git a/arch/arm/include/asm/current.h b/arch/arm/include/asm/current.h index 6bf0aad672c3..69ecf4c6c725 100644 --- a/arch/arm/include/asm/current.h +++ b/arch/arm/include/asm/current.h @@ -8,25 +8,18 @@ #define _ASM_ARM_CURRENT_H #ifndef __ASSEMBLY__ +#include struct task_struct; -static inline void set_current(struct task_struct *cur) -{ - if (!IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO)) - return; +extern struct task_struct *__current; - /* Set TPIDRURO */ - asm("mcr p15, 0, %0, c13, c0, 3" :: "r"(cur) : "memory"); -} - -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO - -static inline struct task_struct *get_current(void) +static inline __attribute_const__ struct task_struct *get_current(void) { struct task_struct *cur; #if __has_builtin(__builtin_thread_pointer) && \ + defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) && \ !(defined(CONFIG_THUMB2_KERNEL) && \ defined(CONFIG_CC_IS_CLANG) && CONFIG_CLANG_VERSION < 130001) /* @@ -39,16 +32,30 @@ static inline struct task_struct *get_current(void) * https://github.com/ClangBuiltLinux/linux/issues/1485 */ cur = __builtin_thread_pointer(); +#elif defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP) + asm("0: mrc p15, 0, %0, c13, c0, 3 \n\t" +#ifdef CONFIG_CPU_V6 + "1: \n\t" + " .subsection 1 \n\t" + "2: " LOAD_SYM_ARMV6(%0, __current) " \n\t" + " b 1b \n\t" + " .previous \n\t" + " .pushsection \".alt.smp.init\", \"a\" \n\t" + " .long 0b - . \n\t" + " b . + (2b - 0b) \n\t" + " .popsection \n\t" +#endif + : "=r"(cur)); +#elif __LINUX_ARM_ARCH__>=7 || \ + (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS)) + cur = __current; #else - asm("mrc p15, 0, %0, c13, c0, 3" : "=r"(cur)); + asm(LOAD_SYM_ARMV6(%0, __current) : "=r"(cur)); #endif return cur; } #define current get_current() -#else -#include -#endif /* CONFIG_CURRENT_POINTER_IN_TPIDRURO */ #endif /* __ASSEMBLY__ */ diff --git a/arch/arm/include/asm/switch_to.h b/arch/arm/include/asm/switch_to.h index b55c7b2755e4..a482c99934ff 100644 --- a/arch/arm/include/asm/switch_to.h +++ b/arch/arm/include/asm/switch_to.h @@ -40,7 +40,8 @@ static inline void set_ti_cpu(struct task_struct *p) do { \ __complete_pending_tlbi(); \ set_ti_cpu(next); \ - if (IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO)) \ + if (IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || \ + IS_ENABLED(CONFIG_SMP)) \ __this_cpu_write(__entry_task, next); \ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \ } while (0) diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index 004b89d86224..aecc403b2880 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -62,9 +62,6 @@ struct cpu_context_save { struct thread_info { unsigned long flags; /* low level flags */ int preempt_count; /* 0 => preemptable, <0 => bug */ -#ifndef CONFIG_THREAD_INFO_IN_TASK - struct task_struct *task; /* main task structure */ -#endif __u32 cpu; /* cpu */ __u32 cpu_domain; /* cpu domain */ struct cpu_context_save cpu_context; /* cpu context */ @@ -80,39 +77,15 @@ struct thread_info { #define INIT_THREAD_INFO(tsk) \ { \ - INIT_THREAD_INFO_TASK(tsk) \ .flags = 0, \ .preempt_count = INIT_PREEMPT_COUNT, \ } -#ifdef CONFIG_THREAD_INFO_IN_TASK -#define INIT_THREAD_INFO_TASK(tsk) - static inline struct task_struct *thread_task(struct thread_info* ti) { return (struct task_struct *)ti; } -#else -#define INIT_THREAD_INFO_TASK(tsk) .task = &(tsk), - -static inline struct task_struct *thread_task(struct thread_info* ti) -{ - return ti->task; -} - -/* - * how to get the thread information struct from C - */ -static inline struct thread_info *current_thread_info(void) __attribute_const__; - -static inline struct thread_info *current_thread_info(void) -{ - return (struct thread_info *) - (current_stack_pointer & ~(THREAD_SIZE - 1)); -} -#endif - #define thread_saved_pc(tsk) \ ((unsigned long)(task_thread_info(tsk)->cpu_context.pc)) #define thread_saved_sp(tsk) \ diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index 645845e4982a..2c8d76fd7c66 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -43,9 +43,6 @@ int main(void) BLANK(); DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count)); -#ifndef CONFIG_THREAD_INFO_IN_TASK - DEFINE(TI_TASK, offsetof(struct thread_info, task)); -#endif DEFINE(TI_CPU, offsetof(struct thread_info, cpu)); DEFINE(TI_CPU_DOMAIN, offsetof(struct thread_info, cpu_domain)); DEFINE(TI_CPU_SAVE, offsetof(struct thread_info, cpu_context)); diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 43d917f0d9a9..b58bda51e4b8 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -807,12 +807,13 @@ ENTRY(__switch_to) switch_tls r1, r4, r5, r3, r7 #if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) && \ !defined(CONFIG_STACKPROTECTOR_PER_TASK) - ldr r9, [r2, #TI_TASK] ldr r8, =__stack_chk_guard .if (TSK_STACK_CANARY > IMM12_MASK) - add r9, r9, #TSK_STACK_CANARY & ~IMM12_MASK - .endif + add r9, r2, #TSK_STACK_CANARY & ~IMM12_MASK ldr r9, [r9, #TSK_STACK_CANARY & IMM12_MASK] + .else + ldr r9, [r2, #TSK_STACK_CANARY & IMM12_MASK] + .endif #endif mov r7, r2 @ Preserve 'next' #ifdef CONFIG_CPU_USE_DOMAINS @@ -829,7 +830,7 @@ ENTRY(__switch_to) #endif mov r0, r5 #if !defined(CONFIG_THUMB2_KERNEL) && !defined(CONFIG_VMAP_STACK) - set_current r7 + set_current r7, r8 ldmia r4, {r4 - sl, fp, sp, pc} @ Load all regs saved previously #else mov r1, r7 @@ -851,7 +852,7 @@ ENTRY(__switch_to) @ switches us to another stack, with few other side effects. In order @ to prevent this distinction from causing any inconsistencies, let's @ keep the 'set_current' call as close as we can to the update of SP. - set_current r1 + set_current r1, r2 mov sp, ip ret lr #endif diff --git a/arch/arm/kernel/entry-v7m.S b/arch/arm/kernel/entry-v7m.S index 520dd43e7e08..4e0d318b67c6 100644 --- a/arch/arm/kernel/entry-v7m.S +++ b/arch/arm/kernel/entry-v7m.S @@ -97,15 +97,17 @@ ENTRY(__switch_to) str sp, [ip], #4 str lr, [ip], #4 mov r5, r0 + mov r6, r2 @ Preserve 'next' add r4, r2, #TI_CPU_SAVE ldr r0, =thread_notify_head mov r1, #THREAD_NOTIFY_SWITCH bl atomic_notifier_call_chain - mov ip, r4 mov r0, r5 - ldmia ip!, {r4 - r11} @ Load all regs saved previously - ldr sp, [ip] - ldr pc, [ip, #4]! + mov r1, r6 + ldmia r4, {r4 - r12, lr} @ Load all regs saved previously + set_current r1, r2 + mov sp, ip + bx lr .fnend ENDPROC(__switch_to) diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index da18e0a17dc2..42cae73fcc19 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -105,10 +105,8 @@ __mmap_switched: mov r1, #0 bl __memset @ clear .bss -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO adr_l r0, init_task @ get swapper task_struct - set_current r0 -#endif + set_current r0, r1 ldmia r4, {r0, r1, r2, r3} str r9, [r0] @ Save processor ID diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index d47159f3791c..0617af11377f 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -36,7 +36,7 @@ #include "signal.h" -#ifdef CONFIG_CURRENT_POINTER_IN_TPIDRURO +#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP) DEFINE_PER_CPU(struct task_struct *, __entry_task); #endif @@ -46,6 +46,11 @@ unsigned long __stack_chk_guard __read_mostly; EXPORT_SYMBOL(__stack_chk_guard); #endif +#ifndef CONFIG_CURRENT_POINTER_IN_TPIDRURO +asmlinkage struct task_struct *__current; +EXPORT_SYMBOL(__current); +#endif + static const char *processor_modes[] __maybe_unused = { "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" , "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26", diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 9c55ca915ba4..951559e5bea3 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -403,6 +403,17 @@ static void smp_store_cpu_info(unsigned int cpuid) check_cpu_icache_size(cpuid); } +static void set_current(struct task_struct *cur) +{ + if (!IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO) && !is_smp()) { + __current = cur; + return; + } + + /* Set TPIDRURO */ + asm("mcr p15, 0, %0, c13, c0, 3" :: "r"(cur) : "memory"); +} + /* * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index b28a705c49cb..3f38357efc46 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -865,7 +865,9 @@ early_initcall(allocate_overflow_stacks); asmlinkage void handle_bad_stack(struct pt_regs *regs) { unsigned long tsk_stk = (unsigned long)current->stack; +#ifdef CONFIG_IRQSTACKS unsigned long irq_stk = (unsigned long)this_cpu_read(irq_stack_ptr); +#endif unsigned long ovf_stk = (unsigned long)this_cpu_read(overflow_stack_ptr); console_verbose(); @@ -873,8 +875,10 @@ asmlinkage void handle_bad_stack(struct pt_regs *regs) pr_emerg("Task stack: [0x%08lx..0x%08lx]\n", tsk_stk, tsk_stk + THREAD_SIZE); +#ifdef CONFIG_IRQSTACKS pr_emerg("IRQ stack: [0x%08lx..0x%08lx]\n", irq_stk - THREAD_SIZE, irq_stk); +#endif pr_emerg("Overflow stack: [0x%08lx..0x%08lx]\n", ovf_stk - OVERFLOW_STACK_SIZE, ovf_stk);