diff options
Diffstat (limited to 'arch/arm/kernel/traps.c')
-rw-r--r-- | arch/arm/kernel/traps.c | 80 |
1 files changed, 49 insertions, 31 deletions
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 18b32e8e4497..b4fd850c34b2 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -34,10 +34,15 @@ #include <asm/unwind.h> #include <asm/tls.h> #include <asm/system_misc.h> - -#include "signal.h" - -static const char *handler[]= { "prefetch abort", "data abort", "address exception", "interrupt" }; +#include <asm/opcodes.h> + +static const char *handler[]= { + "prefetch abort", + "data abort", + "address exception", + "interrupt", + "undefined instruction", +}; void *vectors_page; @@ -343,15 +348,17 @@ void arm_notify_die(const char *str, struct pt_regs *regs, int is_valid_bugaddr(unsigned long pc) { #ifdef CONFIG_THUMB2_KERNEL - unsigned short bkpt; + u16 bkpt; + u16 insn = __opcode_to_mem_thumb16(BUG_INSTR_VALUE); #else - unsigned long bkpt; + u32 bkpt; + u32 insn = __opcode_to_mem_arm(BUG_INSTR_VALUE); #endif if (probe_kernel_address((unsigned *)pc, bkpt)) return 0; - return bkpt == BUG_INSTR_VALUE; + return bkpt == insn; } #endif @@ -404,25 +411,28 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs) if (processor_mode(regs) == SVC_MODE) { #ifdef CONFIG_THUMB2_KERNEL if (thumb_mode(regs)) { - instr = ((u16 *)pc)[0]; + instr = __mem_to_opcode_thumb16(((u16 *)pc)[0]); if (is_wide_instruction(instr)) { - instr <<= 16; - instr |= ((u16 *)pc)[1]; + u16 inst2; + inst2 = __mem_to_opcode_thumb16(((u16 *)pc)[1]); + instr = __opcode_thumb32_compose(instr, inst2); } } else #endif - instr = *(u32 *) pc; + instr = __mem_to_opcode_arm(*(u32 *) pc); } else if (thumb_mode(regs)) { if (get_user(instr, (u16 __user *)pc)) goto die_sig; + instr = __mem_to_opcode_thumb16(instr); if (is_wide_instruction(instr)) { unsigned int instr2; if (get_user(instr2, (u16 __user *)pc+1)) goto die_sig; - instr <<= 16; - instr |= instr2; + instr2 = __mem_to_opcode_thumb16(instr2); + instr = __opcode_thumb32_compose(instr, instr2); } } else if (get_user(instr, (u32 __user *)pc)) { + instr = __mem_to_opcode_arm(instr); goto die_sig; } @@ -800,47 +810,55 @@ void __init trap_init(void) return; } -static void __init kuser_get_tls_init(unsigned long vectors) +#ifdef CONFIG_KUSER_HELPERS +static void __init kuser_init(void *vectors) { + extern char __kuser_helper_start[], __kuser_helper_end[]; + int kuser_sz = __kuser_helper_end - __kuser_helper_start; + + memcpy(vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz); + /* * vectors + 0xfe0 = __kuser_get_tls * vectors + 0xfe8 = hardware TLS instruction at 0xffff0fe8 */ if (tls_emu || has_tls_reg) - memcpy((void *)vectors + 0xfe0, (void *)vectors + 0xfe8, 4); + memcpy(vectors + 0xfe0, vectors + 0xfe8, 4); } +#else +static void __init kuser_init(void *vectors) +{ +} +#endif void __init early_trap_init(void *vectors_base) { unsigned long vectors = (unsigned long)vectors_base; extern char __stubs_start[], __stubs_end[]; extern char __vectors_start[], __vectors_end[]; - extern char __kuser_helper_start[], __kuser_helper_end[]; - int kuser_sz = __kuser_helper_end - __kuser_helper_start; + unsigned i; vectors_page = vectors_base; /* + * Poison the vectors page with an undefined instruction. This + * instruction is chosen to be undefined for both ARM and Thumb + * ISAs. The Thumb version is an undefined instruction with a + * branch back to the undefined instruction. + */ + for (i = 0; i < PAGE_SIZE / sizeof(u32); i++) + ((u32 *)vectors_base)[i] = 0xe7fddef1; + + /* * Copy the vectors, stubs and kuser helpers (in entry-armv.S) * into the vector page, mapped at 0xffff0000, and ensure these * are visible to the instruction stream. */ memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start); - memcpy((void *)vectors + 0x200, __stubs_start, __stubs_end - __stubs_start); - memcpy((void *)vectors + 0x1000 - kuser_sz, __kuser_helper_start, kuser_sz); + memcpy((void *)vectors + 0x1000, __stubs_start, __stubs_end - __stubs_start); - /* - * Do processor specific fixups for the kuser helpers - */ - kuser_get_tls_init(vectors); - - /* - * Copy signal return handlers into the vector page, and - * set sigreturn to be a pointer to these. - */ - memcpy((void *)(vectors + KERN_SIGRETURN_CODE - CONFIG_VECTORS_BASE), - sigreturn_codes, sizeof(sigreturn_codes)); + kuser_init(vectors_base); - flush_icache_range(vectors, vectors + PAGE_SIZE); + flush_icache_range(vectors, vectors + PAGE_SIZE * 2); modify_domain(DOMAIN_USER, DOMAIN_CLIENT); } |