sh: cleanup of do_address_error()

This patch fixes a few problems with the existing code in do_address_error().

a) the variable used to printk()d the offending instruction wasn't
   initialized correctly. This is a fix to bug 5727

b) behaviour for CONFIG_CPU_SH2A wasn't correct

c) the 'ignore address error' behaviour didn't update the PC, causing an
   infinite loop.

Signed-off-by: Andre Draszik <andre.draszik@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 10 insertions, 10 deletions

diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index 0ad356d00ac8..c581dc31d92a 100644
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -621,12 +621,21 @@ asmlinkage void do_address_error(struct pt_regs *regs,
 
                 se_user += 1;
 
+#ifndef CONFIG_CPU_SH2A
+                set_fs(USER_DS);
+                if (copy_from_user(&instruction, (u16 *)(regs->pc & ~1), 2)) {
+                        set_fs(oldfs);
+                        goto uspace_segv;
+                }
+                set_fs(oldfs);
+
                 /* shout about userspace fixups */
                 if (se_usermode & 1)
                         printk(KERN_NOTICE "Unaligned userspace access "
                                "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
                                current->comm, current->pid, (void *)regs->pc,
                                instruction);
+#endif
 
                 if (se_usermode & 2)
                         goto fixup;
@@ -635,7 +644,7 @@ asmlinkage void do_address_error(struct pt_regs *regs,
                         goto uspace_segv;
                 else {
                         /* ignore */
-                        trace_mark(kernel_arch_trap_exit, MARK_NOARGS);
+                        regs->pc += instruction_size(instruction);
                         return;
                 }
 
@@ -647,15 +656,6 @@ fixup:
                 }
 
                 set_fs(USER_DS);
-                if (copy_from_user(&instruction, (void __user *)(regs->pc),
-                                   sizeof(instruction))) {
-                        /* Argh. Fault on the instruction itself.
-                           This should never happen non-SMP
-                        */
-                        set_fs(oldfs);
-                        goto uspace_segv;
-                }
-
                 tmp = handle_unaligned_access(instruction, regs,
                                               &user_mem_access);
                 set_fs(oldfs);