Merge branch 'fix/hda' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6

[pandora-kernel.git] / arch / sparc / kernel / rtrap_64.S

diff --git a/arch/sparc/kernel/rtrap_64.S b/arch/sparc/kernel/rtrap_64.S
index 83f1873..090b9e9 100644 (file)
--- a/arch/sparc/kernel/rtrap_64.S
+++ b/arch/sparc/kernel/rtrap_64.S
@@ -130,7 +130,17 @@ rtrap_xcall:
                 nop
                call                    trace_hardirqs_on
                 nop
-               wrpr                    %l4, %pil
+               /* Do not actually set the %pil here.  We will do that
+                * below after we clear PSTATE_IE in the %pstate register.
+                * If we re-enable interrupts here, we can recurse down
+                * the hardirq stack potentially endlessly, causing a
+                * stack overflow.
+                *
+                * It is tempting to put this test and trace_hardirqs_on
+                * call at the 'rt_continue' label, but that will not work
+                * as that path hits unconditionally and we do not want to
+                * execute this in NMI return paths, for example.
+                */
 #endif
 rtrap_no_irq_enable:
                andcc                   %l1, TSTATE_PRIV, %l3