commit 7f2251b1bcdd3d2971b2fde3008b270ea11b8780
author Jack Steiner <steiner@sgi.com> Tue Dec 15 16:48:08 2009 -0800
committer Linus Torvalds <torvalds@linux-foundation.org> Wed Dec 16 07:20:15 2009 -0800
tree 5fc3a2fc089188a6a61e16374a5b715db280aca7
parent 6c9620c64be3920487c0533e0ab6724dad565d59

gru: handle failures to mmu_notifier_register

Under some conditions, mmu_notifier_register() will fail to register a
mmu_notifier.  Fix the GRU driver to correctly handle these failures.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc/sgi-gru/grufault.c

diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c
index 9470303..ada7df7 100644
--- a/drivers/misc/sgi-gru/grufault.c
+++ b/drivers/misc/sgi-gru/grufault.c
@@ -96,7 +96,7 @@
 	vma = gru_find_vma(vaddr);
 	if (vma)
 		gts = gru_alloc_thread_state(vma, TSID(vaddr, vma));
-	if (gts) {
+	if (!IS_ERR(gts)) {
 		mutex_lock(&gts->ts_ctxlock);
 		downgrade_write(&mm->mmap_sem);
 	} else {
@@ -747,8 +747,8 @@
 	gru_dbg(grudev, "op %d, gseg 0x%lx, value1 0x%lx\n", req.op, req.gseg, req.val1);
 
 	gts = gru_alloc_locked_gts(req.gseg);
-	if (!gts)
-		return -EINVAL;
+	if (IS_ERR(gts))
+		return PTR_ERR(gts);
 
 	switch (req.op) {
 	case sco_blade_chiplet: