powerpc: Disable interrupts for data breakpoint exceptions
Data address breakpoint exceptions are currently handled along with page-faults
which require interrupts to remain in enabled state. Since exception handling
for data breakpoints aren't pre-empt safe, we handle them separately.
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index e3be98f..3e423fb 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -735,8 +735,11 @@
std r3,_DAR(r1)
std r4,_DSISR(r1)
- andis. r0,r4,0xa450 /* weird error? */
+ andis. r0,r4,0xa410 /* weird error? */
bne- handle_page_fault /* if not, try to insert a HPTE */
+ andis. r0,r4,DSISR_DABRMATCH@h
+ bne- handle_dabr_fault
+
BEGIN_FTR_SECTION
andis. r0,r4,0x0020 /* Is it a segment table fault? */
bne- do_ste_alloc /* If so handle it */
@@ -823,6 +826,14 @@
bl .raw_local_irq_restore
b 11f
+/* We have a data breakpoint exception - handle it */
+handle_dabr_fault:
+ ld r4,_DAR(r1)
+ ld r5,_DSISR(r1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl .do_dabr
+ b .ret_from_except_lite
+
/* Here we have a page fault that hash_page can't handle. */
handle_page_fault:
ENABLE_INTS
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 26fb6b9..83ac493 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -151,13 +151,14 @@
if (!user_mode(regs) && (address >= TASK_SIZE))
return SIGSEGV;
-#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
+#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE) || \
+ defined(CONFIG_PPC_BOOK3S_64))
if (error_code & DSISR_DABRMATCH) {
/* DABR match */
do_dabr(regs, address, error_code);
return 0;
}
-#endif /* !(CONFIG_4xx || CONFIG_BOOKE)*/
+#endif
if (in_atomic() || mm == NULL) {
if (!user_mode(regs))