From: David S. Miller <davem@sunset.davemloft.net>
Date: Thu, 23 Feb 2006 00:15:45 +0000 (-0800)
Subject: [SPARC64]: Drop %gl to 0 before re-enabling PSTATE_IE in rtrap
X-Git-Tag: firefly_0821_release~37607^2~46
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fc504928677049f0ad3f1fd4e0bb3908172df8f3;p=firefly-linux-kernel-4.4.55.git

[SPARC64]: Drop %gl to 0 before re-enabling PSTATE_IE in rtrap

If we take a window fault, on SUN4V set %gl to zero before we
turn PSTATE_IE back on in %pstate.  Otherwise if we take an
interrupt we'll end up with corrupt register state.

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

diff --git a/arch/sparc64/kernel/rtrap.S b/arch/sparc64/kernel/rtrap.S
index 1e724fe172ae..7130e866f935 100644
--- a/arch/sparc64/kernel/rtrap.S
+++ b/arch/sparc64/kernel/rtrap.S
@@ -333,7 +333,6 @@ user_rtt_fill_fixup:
 
 		mov	%g6, %l1
 		wrpr	%g0, 0x0, %tl
-		wrpr	%g0, RTRAP_PSTATE, %pstate
 
 661:		nop
 		.section		.sun4v_1insn_patch, "ax"
@@ -341,6 +340,8 @@ user_rtt_fill_fixup:
 		SET_GL(0)
 		.previous
 
+		wrpr	%g0, RTRAP_PSTATE, %pstate
+
 		mov	%l1, %g6
 		ldx	[%g6 + TI_TASK], %g4
 		LOAD_PER_CPU_BASE(%g5, %g6, %g1, %g2, %g3)