1 files changed, 52 insertions, 58 deletions

diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index 785a51b0ad8e..69f88d561d62 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -470,18 +470,6 @@ ENTRY(load_switch_stack)
         br.cond.sptk.many b7
 END(load_switch_stack)
 
-GLOBAL_ENTRY(__ia64_syscall)
-        .regstk 6,0,0,0
-        mov r15=in5                             // put syscall number in place
-        break __BREAK_SYSCALL
-        movl r2=errno
-        cmp.eq p6,p7=-1,r10
-        ;;
-(p6)    st4 [r2]=r8
-(p6)    mov r8=-1
-        br.ret.sptk.many rp
-END(__ia64_syscall)
-
 GLOBAL_ENTRY(execve)
         mov r15=__NR_execve                     // put syscall number in place
         break __BREAK_SYSCALL
@@ -637,7 +625,7 @@ END(ia64_ret_from_syscall)
  *            r8-r11: restored (syscall return value(s))
  *               r12: restored (user-level stack pointer)
  *               r13: restored (user-level thread pointer)
- *               r14: cleared
+ *               r14: set to __kernel_syscall_via_epc
  *               r15: restored (syscall #)
  *           r16-r17: cleared
  *               r18: user-level b6
@@ -658,7 +646,7 @@ END(ia64_ret_from_syscall)
  *                pr: restored (user-level pr)
  *                b0: restored (user-level rp)
  *                b6: restored
- *                b7: cleared
+ *                b7: set to __kernel_syscall_via_epc
  *           ar.unat: restored (user-level ar.unat)
  *            ar.pfs: restored (user-level ar.pfs)
  *            ar.rsc: restored (user-level ar.rsc)
@@ -704,72 +692,79 @@ ENTRY(ia64_leave_syscall)
         ;;
 (p6)    ld4 r31=[r18]                           // load current_thread_info()->flags
         ld8 r19=[r2],PT(B6)-PT(LOADRS)          // load ar.rsc value for "loadrs"
-        mov b7=r0               // clear b7
+        nop.i 0
         ;;
-        ld8 r23=[r3],PT(R11)-PT(AR_BSPSTORE)    // load ar.bspstore (may be garbage)
+        mov r16=ar.bsp                          // M2  get existing backing store pointer
         ld8 r18=[r2],PT(R9)-PT(B6)              // load b6
 (p6)    and r15=TIF_WORK_MASK,r31               // any work other than TIF_SYSCALL_TRACE?
         ;;
-        mov r16=ar.bsp                          // M2  get existing backing store pointer
+        ld8 r23=[r3],PT(R11)-PT(AR_BSPSTORE)    // load ar.bspstore (may be garbage)
 (p6)    cmp4.ne.unc p6,p0=r15, r0               // any special work pending?
 (p6)    br.cond.spnt .work_pending_syscall
         ;;
         // start restoring the state saved on the kernel stack (struct pt_regs):
         ld8 r9=[r2],PT(CR_IPSR)-PT(R9)
         ld8 r11=[r3],PT(CR_IIP)-PT(R11)
-        mov f6=f0               // clear f6
+(pNonSys) break 0               //      bug check: we shouldn't be here if pNonSys is TRUE!
         ;;
         invala                  // M0|1 invalidate ALAT
-        rsm psr.i | psr.ic      // M2 initiate turning off of interrupt and interruption collection
-        mov f9=f0               // clear f9
+        rsm psr.i | psr.ic      // M2   turn off interrupts and interruption collection
+        cmp.eq p9,p0=r0,r0      // A    set p9 to indicate that we should restore cr.ifs
 
-        ld8 r29=[r2],16         // load cr.ipsr
-        ld8 r28=[r3],16                 // load cr.iip
-        mov f8=f0               // clear f8
+        ld8 r29=[r2],16         // M0|1 load cr.ipsr
+        ld8 r28=[r3],16         // M0|1 load cr.iip
+        mov r22=r0              // A    clear r22
         ;;
         ld8 r30=[r2],16         // M0|1 load cr.ifs
         ld8 r25=[r3],16         // M0|1 load ar.unat
-        cmp.eq p9,p0=r0,r0      // set p9 to indicate that we should restore cr.ifs
+(pUStk) add r14=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13
         ;;
         ld8 r26=[r2],PT(B0)-PT(AR_PFS)  // M0|1 load ar.pfs
-(pKStk) mov r22=psr             // M2 read PSR now that interrupts are disabled
-        mov f10=f0              // clear f10
+(pKStk) mov r22=psr                     // M2   read PSR now that interrupts are disabled
+        nop 0
         ;;
-        ld8 r21=[r2],PT(AR_RNAT)-PT(B0) // load b0
-        ld8 r27=[r3],PT(PR)-PT(AR_RSC)  // load ar.rsc
-        mov f11=f0              // clear f11
+        ld8 r21=[r2],PT(AR_RNAT)-PT(B0) // M0|1 load b0
+        ld8 r27=[r3],PT(PR)-PT(AR_RSC)  // M0|1 load ar.rsc
+        mov f6=f0                       // F    clear f6
         ;;
-        ld8 r24=[r2],PT(AR_FPSR)-PT(AR_RNAT)    // load ar.rnat (may be garbage)
-        ld8 r31=[r3],PT(R1)-PT(PR)              // load predicates
-(pUStk) add r14=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13
+        ld8 r24=[r2],PT(AR_FPSR)-PT(AR_RNAT)    // M0|1 load ar.rnat (may be garbage)
+        ld8 r31=[r3],PT(R1)-PT(PR)              // M0|1 load predicates
+        mov f7=f0                               // F    clear f7
         ;;
-        ld8 r20=[r2],PT(R12)-PT(AR_FPSR)        // load ar.fpsr
-        ld8.fill r1=[r3],16     // load r1
-(pUStk) mov r17=1
+        ld8 r20=[r2],PT(R12)-PT(AR_FPSR)        // M0|1 load ar.fpsr
+        ld8.fill r1=[r3],16                     // M0|1 load r1
+(pUStk) mov r17=1                               // A
         ;;
-        srlz.d                  // M0  ensure interruption collection is off
-        ld8.fill r13=[r3],16
-        mov f7=f0               // clear f7
+(pUStk) st1 [r14]=r17                           // M2|3
+        ld8.fill r13=[r3],16                    // M0|1
+        mov f8=f0                               // F    clear f8
         ;;
-        ld8.fill r12=[r2]       // restore r12 (sp)
-        mov.m ar.ssd=r0         // M2 clear ar.ssd
-        mov r22=r0              // clear r22
+        ld8.fill r12=[r2]                       // M0|1 restore r12 (sp)
+        ld8.fill r15=[r3]                       // M0|1 restore r15
+        mov b6=r18                              // I0   restore b6
 
-        ld8.fill r15=[r3]       // restore r15
-(pUStk) st1 [r14]=r17
-        addl r3=THIS_CPU(ia64_phys_stacked_size_p8),r0
+        addl r17=THIS_CPU(ia64_phys_stacked_size_p8),r0 // A
+        mov f9=f0                                       // F    clear f9
+(pKStk) br.cond.dpnt.many skip_rbs_switch               // B
+
+        srlz.d                          // M0   ensure interruption collection is off (for cover)
+        shr.u r18=r19,16                // I0|1 get byte size of existing "dirty" partition
+        cover                           // B    add current frame into dirty partition & set cr.ifs
         ;;
-(pUStk) ld4 r17=[r3]            // r17 = cpu_data->phys_stacked_size_p8
-        mov.m ar.csd=r0         // M2 clear ar.csd
-        mov b6=r18              // I0  restore b6
+(pUStk) ld4 r17=[r17]                   // M0|1 r17 = cpu_data->phys_stacked_size_p8
+        mov r19=ar.bsp                  // M2   get new backing store pointer
+        mov f10=f0                      // F    clear f10
+
+        nop.m 0
+        movl r14=__kernel_syscall_via_epc // X
         ;;
-        mov r14=r0              // clear r14
-        shr.u r18=r19,16        // I0|1 get byte size of existing "dirty" partition
-(pKStk) br.cond.dpnt.many skip_rbs_switch
+        mov.m ar.csd=r0                 // M2   clear ar.csd
+        mov.m ar.ccv=r0                 // M2   clear ar.ccv
+        mov b7=r14                      // I0   clear b7 (hint with __kernel_syscall_via_epc)
 
-        mov.m ar.ccv=r0         // clear ar.ccv
-(pNonSys) br.cond.dpnt.many dont_preserve_current_frame
-        br.cond.sptk.many rbs_switch
+        mov.m ar.ssd=r0                 // M2   clear ar.ssd
+        mov f11=f0                      // F    clear f11
+        br.cond.sptk.many rbs_switch    // B
 END(ia64_leave_syscall)
 
 #ifdef CONFIG_IA32_SUPPORT
@@ -885,7 +880,7 @@ GLOBAL_ENTRY(ia64_leave_kernel)
         ldf.fill f7=[r2],PT(F11)-PT(F7)
         ldf.fill f8=[r3],32
         ;;
-        srlz.i                  // ensure interruption collection is off
+        srlz.d  // ensure that inter. collection is off (VHPT is don't care, since text is pinned)
         mov ar.ccv=r15
         ;;
         ldf.fill f11=[r2]
@@ -945,11 +940,10 @@ GLOBAL_ENTRY(ia64_leave_kernel)
          * NOTE: alloc, loadrs, and cover can't be predicated.
          */
 (pNonSys) br.cond.dpnt dont_preserve_current_frame
-
-rbs_switch:
         cover                           // add current frame into dirty partition and set cr.ifs
         ;;
         mov r19=ar.bsp                  // get new backing store pointer
+rbs_switch:
         sub r16=r16,r18                 // krbs = old bsp - size of dirty partition
         cmp.ne p9,p0=r0,r0              // clear p9 to skip restore of cr.ifs
         ;;
@@ -1024,14 +1018,14 @@ rse_clear_invalid:
         mov loc5=0
         mov loc6=0
         mov loc7=0
-(pRecurse) br.call.sptk.few b0=rse_clear_invalid
+(pRecurse) br.call.dptk.few b0=rse_clear_invalid
         ;;
         mov loc8=0
         mov loc9=0
         cmp.ne pReturn,p0=r0,in1        // if recursion count != 0, we need to do a br.ret
         mov loc10=0
         mov loc11=0
-(pReturn) br.ret.sptk.many b0
+(pReturn) br.ret.dptk.many b0
 #endif /* !CONFIG_ITANIUM */
 #       undef pRecurse
 #       undef pReturn