diff options
Diffstat (limited to 'arch/arm/kernel/entry-armv.S')
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 30 |
1 files changed, 17 insertions, 13 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index d40d0ef389d..52a949a8077 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -192,6 +192,7 @@ __dabt_svc: svc_entry mov r2, sp dabt_helper + THUMB( ldr r5, [sp, #S_PSR] ) @ potentially updated CPSR svc_exit r5 @ return from exception UNWIND(.fnend ) ENDPROC(__dabt_svc) @@ -343,7 +344,7 @@ ENDPROC(__pabt_svc) @ @ Enable the alignment trap while in kernel mode @ - alignment_trap r0 + alignment_trap r0, .LCcralign @ @ Clear FP to mark the first stack frame @@ -357,7 +358,8 @@ ENDPROC(__pabt_svc) .endm .macro kuser_cmpxchg_check -#if !defined(CONFIG_CPU_32v6K) && !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG) +#if !defined(CONFIG_CPU_32v6K) && defined(CONFIG_KUSER_HELPERS) && \ + !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG) #ifndef CONFIG_MMU #warning "NPTL on non MMU needs fixing" #else @@ -411,13 +413,17 @@ __und_usr: @ adr r9, BSYM(ret_from_exception) + @ IRQs must be enabled before attempting to read the instruction from + @ user space since that could cause a page/translation fault if the + @ page table was modified by another CPU. + enable_irq + tst r3, #PSR_T_BIT @ Thumb mode? bne __und_usr_thumb sub r4, r2, #4 @ ARM instr at LR - 4 1: ldrt r0, [r4] -#ifdef CONFIG_CPU_ENDIAN_BE8 - rev r0, r0 @ little endian instruction -#endif + ARM_BE8(rev r0, r0) @ little endian instruction + @ 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 @@ -450,9 +456,11 @@ __und_usr_thumb: .arch armv6t2 #endif 2: ldrht r5, [r4] +ARM_BE8(rev16 r5, r5) @ little endian instruction cmp r5, #0xe800 @ 32bit instruction if xx != 0 blo __und_usr_fault_16 @ 16bit undefined instruction 3: ldrht r0, [r2] +ARM_BE8(rev16 r0, r0) @ little endian instruction 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 @@ -481,7 +489,8 @@ ENDPROC(__und_usr) */ .pushsection .fixup, "ax" .align 2 -4: mov pc, r9 +4: str r4, [sp, #S_PC] @ retry current instruction + mov pc, r9 .popsection .pushsection __ex_table,"a" .long 1b, 4b @@ -514,7 +523,7 @@ ENDPROC(__und_usr) * r9 = normal "successful" return address * r10 = this threads thread_info structure * lr = unrecognised instruction return address - * IRQs disabled, FIQs enabled. + * IRQs enabled, FIQs enabled. */ @ @ Fall-through from Thumb-2 __und_usr @@ -621,7 +630,6 @@ call_fpe: #endif do_fpe: - enable_irq ldr r4, .LCfp add r10, r10, #TI_FPSTATE @ r10 = workspace ldr pc, [r4] @ Call FP module USR entry point @@ -649,8 +657,7 @@ __und_usr_fault_32: b 1f __und_usr_fault_16: mov r1, #2 -1: enable_irq - mov r0, sp +1: mov r0, sp adr lr, BSYM(ret_from_exception) b __und_fault ENDPROC(__und_usr_fault_32) @@ -1140,11 +1147,8 @@ __vectors_start: .data .globl cr_alignment - .globl cr_no_alignment cr_alignment: .space 4 -cr_no_alignment: - .space 4 #ifdef CONFIG_MULTI_IRQ_HANDLER .globl handle_arch_irq |