diff options
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 111 | ||||
| -rw-r--r-- | arch/arm/kernel/ftrace.c | 17 | ||||
| -rw-r--r-- | arch/arm/kernel/process.c | 2 | ||||
| -rw-r--r-- | arch/arm/kernel/setup.c | 6 | ||||
| -rw-r--r-- | arch/arm/kernel/smp.c | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/traps.c | 8 |
6 files changed, 88 insertions, 59 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 0d1851ca6eb9..0f82098c9bfe 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -244,6 +244,19 @@ svc_preempt: b 1b #endif +__und_fault: + @ Correct the PC such that it is pointing at the instruction + @ which caused the fault. If the faulting instruction was ARM + @ the PC will be pointing at the next instruction, and have to + @ subtract 4. Otherwise, it is Thumb, and the PC will be + @ pointing at the second half of the Thumb instruction. We + @ have to subtract 2. + ldr r2, [r0, #S_PC] + sub r2, r2, r1 + str r2, [r0, #S_PC] + b do_undefinstr +ENDPROC(__und_fault) + .align 5 __und_svc: #ifdef CONFIG_KPROBES @@ -261,25 +274,32 @@ __und_svc: @ @ r0 - instruction @ -#ifndef CONFIG_THUMB2_KERNEL +#ifndef CONFIG_THUMB2_KERNEL ldr r0, [r4, #-4] #else + mov r1, #2 ldrh r0, [r4, #-2] @ Thumb instruction at LR - 2 cmp r0, #0xe800 @ 32-bit instruction if xx >= 0 - ldrhhs r9, [r4] @ bottom 16 bits - orrhs r0, r9, r0, lsl #16 + blo __und_svc_fault + ldrh r9, [r4] @ bottom 16 bits + add r4, r4, #2 + str r4, [sp, #S_PC] + orr r0, r9, r0, lsl #16 #endif - adr r9, BSYM(1f) + adr r9, BSYM(__und_svc_finish) mov r2, r4 bl call_fpe + mov r1, #4 @ PC correction to apply +__und_svc_fault: mov r0, sp @ struct pt_regs *regs - bl do_undefinstr + bl __und_fault @ @ IRQs off again before pulling preserved data off the stack @ -1: disable_irq_notrace +__und_svc_finish: + disable_irq_notrace @ @ restore SPSR and restart the instruction @@ -423,25 +443,33 @@ __und_usr: mov r2, r4 mov r3, r5 + @ r2 = regs->ARM_pc, which is either 2 or 4 bytes ahead of the + @ faulting instruction depending on Thumb mode. + @ r3 = regs->ARM_cpsr @ - @ fall through to the emulation code, which returns using r9 if - @ it has emulated the instruction, or the more conventional lr - @ if we are to treat this as a real undefined instruction - @ - @ r0 - instruction + @ The emulation code returns using r9 if it has emulated the + @ instruction, or the more conventional lr if we are to treat + @ this as a real undefined instruction @ adr r9, BSYM(ret_from_exception) - adr lr, BSYM(__und_usr_unknown) + tst r3, #PSR_T_BIT @ Thumb mode? - itet eq @ explicit IT needed for the 1f label - subeq r4, r2, #4 @ ARM instr at LR - 4 - subne r4, r2, #2 @ Thumb instr at LR - 2 -1: ldreqt r0, [r4] + bne __und_usr_thumb + sub r4, r2, #4 @ ARM instr at LR - 4 +1: ldrt r0, [r4] #ifdef CONFIG_CPU_ENDIAN_BE8 - reveq r0, r0 @ little endian instruction + rev r0, r0 @ little endian instruction #endif - beq call_fpe + @ r0 = 32-bit ARM instruction which caused the exception + @ r2 = PC value for the following instruction (:= regs->ARM_pc) + @ r4 = PC value for the faulting instruction + @ lr = 32-bit undefined instruction function + adr lr, BSYM(__und_usr_fault_32) + b call_fpe + +__und_usr_thumb: @ Thumb instruction + sub r4, r2, #2 @ First half of thumb instr at LR - 2 #if CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7 /* * Thumb-2 instruction handling. Note that because pre-v6 and >= v6 platforms @@ -455,7 +483,7 @@ __und_usr: ldr r5, .LCcpu_architecture ldr r5, [r5] cmp r5, #CPU_ARCH_ARMv7 - blo __und_usr_unknown + blo __und_usr_fault_16 @ 16bit undefined instruction /* * The following code won't get run unless the running CPU really is v7, so * coding round the lack of ldrht on older arches is pointless. Temporarily @@ -463,15 +491,18 @@ __und_usr: */ .arch armv6t2 #endif -2: - ARM( ldrht r5, [r4], #2 ) - THUMB( ldrht r5, [r4] ) - THUMB( add r4, r4, #2 ) +2: ldrht r5, [r4] cmp r5, #0xe800 @ 32bit instruction if xx != 0 - blo __und_usr_unknown -3: ldrht r0, [r4] + blo __und_usr_fault_16 @ 16bit undefined instruction +3: ldrht r0, [r2] add r2, r2, #2 @ r2 is PC + 2, make it PC + 4 + str r2, [sp, #S_PC] @ it's a 2x16bit instr, update orr r0, r0, r5, lsl #16 + adr lr, BSYM(__und_usr_fault_32) + @ r0 = the two 16-bit Thumb instructions which caused the exception + @ r2 = PC value for the following Thumb instruction (:= regs->ARM_pc) + @ r4 = PC value for the first 16-bit Thumb instruction + @ lr = 32bit undefined instruction function #if __LINUX_ARM_ARCH__ < 7 /* If the target arch was overridden, change it back: */ @@ -482,17 +513,13 @@ __und_usr: #endif #endif /* __LINUX_ARM_ARCH__ < 7 */ #else /* !(CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7) */ - b __und_usr_unknown + b __und_usr_fault_16 #endif - UNWIND(.fnend ) + UNWIND(.fnend) ENDPROC(__und_usr) - @ - @ fallthrough to call_fpe - @ - /* - * The out of line fixup for the ldrt above. + * The out of line fixup for the ldrt instructions above. */ .pushsection .fixup, "ax" .align 2 @@ -524,11 +551,12 @@ ENDPROC(__und_usr) * NEON handler code. * * Emulators may wish to make use of the following registers: - * r0 = instruction opcode. - * r2 = PC+4 + * r0 = instruction opcode (32-bit ARM or two 16-bit Thumb) + * r2 = PC value to resume execution after successful emulation * r9 = normal "successful" return address - * r10 = this threads thread_info structure. + * r10 = this threads thread_info structure * lr = unrecognised instruction return address + * IRQs disabled, FIQs enabled. */ @ @ Fall-through from Thumb-2 __und_usr @@ -659,12 +687,17 @@ ENTRY(no_fp) mov pc, lr ENDPROC(no_fp) -__und_usr_unknown: - enable_irq +__und_usr_fault_32: + mov r1, #4 + b 1f +__und_usr_fault_16: + mov r1, #2 +1: enable_irq mov r0, sp adr lr, BSYM(ret_from_exception) - b do_undefinstr -ENDPROC(__und_usr_unknown) + b __und_fault +ENDPROC(__und_usr_fault_32) +ENDPROC(__und_usr_fault_16) .align 5 __pabt_usr: diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c index df0bf0c8cb79..34e56647dcee 100644 --- a/arch/arm/kernel/ftrace.c +++ b/arch/arm/kernel/ftrace.c @@ -179,19 +179,20 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, old = *parent; *parent = return_hooker; - err = ftrace_push_return_trace(old, self_addr, &trace.depth, - frame_pointer); - if (err == -EBUSY) { - *parent = old; - return; - } - trace.func = self_addr; + trace.depth = current->curr_ret_stack + 1; /* Only trace if the calling function expects to */ if (!ftrace_graph_entry(&trace)) { - current->curr_ret_stack--; *parent = old; + return; + } + + err = ftrace_push_return_trace(old, self_addr, &trace.depth, + frame_pointer); + if (err == -EBUSY) { + *parent = old; + return; } } diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 19c95ea65b2f..693b744fd572 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -247,6 +247,7 @@ void machine_shutdown(void) void machine_halt(void) { machine_shutdown(); + local_irq_disable(); while (1); } @@ -268,6 +269,7 @@ void machine_restart(char *cmd) /* Whoops - the platform was unable to reboot. Tell the user! */ printk("Reboot failed -- System halted\n"); + local_irq_disable(); while (1); } diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index e15d83bb4ea3..a81dcecc7343 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -508,7 +508,7 @@ void __init dump_machine_table(void) /* can't use cpu_relax() here as it may require MMU setup */; } -int __init arm_add_memory(phys_addr_t start, unsigned long size) +int __init arm_add_memory(phys_addr_t start, phys_addr_t size) { struct membank *bank = &meminfo.bank[meminfo.nr_banks]; @@ -538,7 +538,7 @@ int __init arm_add_memory(phys_addr_t start, unsigned long size) } #endif - bank->size = size & PAGE_MASK; + bank->size = size & ~(phys_addr_t)(PAGE_SIZE - 1); /* * Check whether this memory region has non-zero size or @@ -558,7 +558,7 @@ int __init arm_add_memory(phys_addr_t start, unsigned long size) static int __init early_mem(char *p) { static int usermem __initdata = 0; - unsigned long size; + phys_addr_t size; phys_addr_t start; char *endp; diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index aea74f5bc34a..ebd8ad274d76 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -563,7 +563,8 @@ void smp_send_stop(void) cpumask_copy(&mask, cpu_online_mask); cpumask_clear_cpu(smp_processor_id(), &mask); - smp_cross_call(&mask, IPI_CPU_STOP); + if (!cpumask_empty(&mask)) + smp_cross_call(&mask, IPI_CPU_STOP); /* Wait up to one second for other CPUs to stop */ timeout = USEC_PER_SEC; diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 8b97d739b17b..7978d4f0f3ae 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -402,18 +402,10 @@ static int call_undef_hook(struct pt_regs *regs, unsigned int instr) asmlinkage void __exception do_undefinstr(struct pt_regs *regs) { - unsigned int correction = thumb_mode(regs) ? 2 : 4; unsigned int instr; siginfo_t info; void __user *pc; - /* - * According to the ARM ARM, PC is 2 or 4 bytes ahead, - * depending whether we're in Thumb mode or not. - * Correct this offset. - */ - regs->ARM_pc -= correction; - pc = (void __user *)instruction_pointer(regs); if (processor_mode(regs) == SVC_MODE) { |