[IA64] need r29=psr *after* rsm psr.i

Yanmin Zhang pointed out a sequence problem when saving the psr.  David
Mosberger provided this patch (which gave up a cycle).

Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/arch/ia64/kernel/gate.S b/arch/ia64/kernel/gate.S
index 272e64c0e21bc6705d7c5062ed2182fb81917b16..86948ce63e43ac8ac583eec74622434b86e5cd73 100644 (file)
--- a/arch/ia64/kernel/gate.S
+++ b/arch/ia64/kernel/gate.S
@@ -77,7 +77,7 @@ GLOBAL_ENTRY(__kernel_syscall_via_epc)
        epc                                     // B    causes split-issue
 }
        ;;
-       rsm psr.be                              // M2 (5 cyc to srlz.d)
+       rsm psr.be | psr.i                      // M2 (5 cyc to srlz.d)
        LOAD_FSYSCALL_TABLE(r14)                // X
        ;;
        mov r16=IA64_KR(CURRENT)                // M2 (12 cyc)
@@ -98,15 +98,14 @@ GLOBAL_ENTRY(__kernel_syscall_via_epc)
        nop.i 0
        ;;
        nop.m 0
-(p6)   mov b7=r18                              // I0
 (p6)   tbit.z.unc p8,p0=r18,0                  // I0 (dual-issues with "mov b7=r18"!)
-
-       nop.m 0
        nop.i 0
+       ;;
+(p8)   ssm psr.i
+(p6)   mov b7=r18                              // I0
 (p8)   br.dptk.many b7                         // B
 
        mov r27=ar.rsc                          // M2 (12 cyc)
-(p6)   rsm psr.i                               // M2
 /*
  * brl.cond doesn't work as intended because the linker would convert this branch
  * into a branch to a PLT.  Perhaps there will be a way to avoid this with some
@@ -123,7 +122,7 @@ GLOBAL_ENTRY(__kernel_syscall_via_epc)
 #else
        BRL_COND_FSYS_BUBBLE_DOWN(p6)
 #endif
-
+       ssm psr.i
        mov r10=-1
 (p10)  mov r8=EINVAL
 (p9)   mov r8=ENOSYS