[IA64] Failure to resume after INIT in user space

The OS INIT handler is loading incorrect values into cr.ifa on exit.
This shows up as a hang when resuming after an INIT that is delivered
while a cpu is in user space.  Correct the value loaded into cr.ifa.

Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/arch/ia64/kernel/mca_asm.S b/arch/ia64/kernel/mca_asm.S
index 60a464b..6dff024 100644 (file)
--- a/arch/ia64/kernel/mca_asm.S
+++ b/arch/ia64/kernel/mca_asm.S
@@ -827,7 +827,7 @@ ia64_state_restore:
        ld8 r9=[temp2],16       // sal_gp
        ;;
        ld8 r22=[temp1],16      // pal_min_state, virtual
-       ld8 r21=[temp2],16      // prev_IA64_KR_CURRENT
+       ld8 r13=[temp2],16      // prev_IA64_KR_CURRENT
        ;;
        ld8 r16=[temp1],16      // prev_IA64_KR_CURRENT_STACK
        ld8 r20=[temp2],16      // prev_task
@@ -848,7 +848,7 @@ ia64_state_restore:
        mov cr.iim=temp3
        mov cr.iha=temp4
        dep r22=0,r22,62,1      // pal_min_state, physical, uncached
-       mov IA64_KR(CURRENT)=r21
+       mov IA64_KR(CURRENT)=r13
        ld8 r8=[temp1]          // os_status
        ld8 r10=[temp2]         // context
 
@@ -856,7 +856,7 @@ ia64_state_restore:
         * avoid any dependencies on the algorithm in ia64_switch_to(), just
         * purge any existing CURRENT_STACK mapping and insert the new one.
         *
-        * r16 contains prev_IA64_KR_CURRENT_STACK, r21 contains
+        * r16 contains prev_IA64_KR_CURRENT_STACK, r13 contains
         * prev_IA64_KR_CURRENT, these values may have been changed by the C
         * code.  Do not use r8, r9, r10, r22, they contain values ready for
         * the return to SAL.
@@ -873,7 +873,7 @@ ia64_state_restore:
        ;;
        srlz.d
 
-       extr.u r19=r21,61,3                     // r21 = prev_IA64_KR_CURRENT
+       extr.u r19=r13,61,3                     // r13 = prev_IA64_KR_CURRENT
        shl r20=r16,IA64_GRANULE_SHIFT          // r16 = prev_IA64_KR_CURRENT_STACK
        movl r21=PAGE_KERNEL                    // page properties
        ;;
@@ -883,7 +883,7 @@ ia64_state_restore:
 (p6)   br.spnt 1f                              // the dreaded cpu 0 idle task in region 5:(
        ;;
        mov cr.itir=r18
-       mov cr.ifa=r21
+       mov cr.ifa=r13
        mov r20=IA64_TR_CURRENT_STACK
        ;;
        itr.d dtr[r20]=r21