Subject: spufs: catch nosched contexts in spu_deactivate

From: Christoph Hellwig <hch@lst.de>
spu_deactivate should never be called for nosched contets.  Put in
a check so we can print a stacktrace and exit early in case it
happes errornously.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>

Index: linux-2.6/arch/powerpc/platforms/cell/spufs/sched.c
===================================================================
--- linux-2.6.orig/arch/powerpc/platforms/cell/spufs/sched.c
+++ linux-2.6/arch/powerpc/platforms/cell/spufs/sched.c
@@ -669,6 +669,15 @@ static int __spu_deactivate(struct spu_c
  */
 void spu_deactivate(struct spu_context *ctx)
 {
+	/*
+	 * We must never reach this for a nosched context,
+	 * but handle the case gracefull instead of panicing.
+	 */
+	if (ctx->flags & SPU_CREATE_NOSCHED) {
+		WARN_ON(1);
+		return;
+	}
+
 	__spu_deactivate(ctx, 1, MAX_PRIO);
 }