diff options
Diffstat (limited to 'arch/arm/kernel/entry-armv.S')
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 1879e8dd2acc..52a949a8077d 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -344,7 +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 @@ -413,6 +413,11 @@ __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 @@ -484,7 +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 @@ -517,7 +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 @@ -624,7 +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 @@ -652,8 +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) @@ -1143,11 +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 |