[SPARC64]: Do not call winfix_dax blindly

Verify we really are taking a data access exception trap, at TL1, from
one of the window spill/fill handlers.

Else call a new function, data_access_exception_tl1, to log the error.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 27 insertions, 0 deletions

diff --git a/arch/sparc64/kernel/entry.S b/arch/sparc64/kernel/entry.S
index 6d0476ff4ff8..214cd0ebe832 100644
--- a/arch/sparc64/kernel/entry.S
+++ b/arch/sparc64/kernel/entry.S
@@ -701,8 +701,24 @@ __do_data_access_exception_tl1:
         ldxa            [%g5] ASI_DMMU, %g5     ! Get SFAR
         stxa            %g0, [%g3] ASI_DMMU     ! Clear SFSR.FaultValid bit
         membar          #Sync
+        rdpr            %tt, %g3
+        cmp             %g3, 0x80               ! first win spill/fill trap
+        blu,pn          %xcc, 1f
+         cmp            %g3, 0xff               ! last win spill/fill trap
+        bgu,pn          %xcc, 1f
+         nop
         ba,pt           %xcc, winfix_dax
          rdpr           %tpc, %g3
+1:      sethi           %hi(109f), %g7
+        ba,pt           %xcc, etraptl1
+109:     or             %g7, %lo(109b), %g7
+        mov             %l4, %o1
+        mov             %l5, %o2
+        call            data_access_exception_tl1
+         add            %sp, PTREGS_OFF, %o0
+        ba,pt           %xcc, rtrap
+         clr            %l6
+
 __do_data_access_exception:
         rdpr            %pstate, %g4
         wrpr            %g4, PSTATE_MG|PSTATE_AG, %pstate
diff --git a/arch/sparc64/kernel/traps.c b/arch/sparc64/kernel/traps.c
index 0c9e54b2f0c8..210b3e321c29 100644
--- a/arch/sparc64/kernel/traps.c
+++ b/arch/sparc64/kernel/traps.c
@@ -220,6 +220,17 @@ void data_access_exception(struct pt_regs *regs,
         force_sig_info(SIGSEGV, &info, current);
 }
 
+void data_access_exception_tl1(struct pt_regs *regs,
+                               unsigned long sfsr, unsigned long sfar)
+{
+        if (notify_die(DIE_TRAP_TL1, "data access exception tl1", regs,
+                       0, 0x30, SIGTRAP) == NOTIFY_STOP)
+                return;
+
+        dump_tl1_traplog((struct tl1_traplog *)(regs + 1));
+        data_access_exception(regs, sfsr, sfar);
+}
+
 #ifdef CONFIG_PCI
 /* This is really pathetic... */
 extern volatile int pci_poke_in_progress;