[PATCH 3/3] drivers/misc/sgi-gru: fix return of error

Sudip Mukherjee
2015-09-21T10:18:45Z

If kzalloc() fails then gms is NULL and we are returning NULL, but the
functions which called this function gru_register_mmu_notifier() are not
expecting NULL as the return. They are expecting either a valid pointer
or the error code in ERR_PTR.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
---

The patch at https://patchwork.kernel.org/patch/6394911/ is not applied
and not relevant now as gms is checked before gru_dbg. But the idea for
this patch was obtained from that one.

drivers/misc/sgi-gru/grutlbpurge.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/misc/sgi-gru/grutlbpurge.c b/drivers/misc/sgi-gru/grutlbpurge.c
index 757a8e9..e936d43 100644
--- a/drivers/misc/sgi-gru/grutlbpurge.c
+++ b/drivers/misc/sgi-gru/grutlbpurge.c
@@ -306,16 +306,16 @@ struct gru_mm_struct *gru_register_mmu_notifier(void)
atomic_inc(&gms->ms_refcnt);
} else {
gms = kzalloc(sizeof(*gms), GFP_KERNEL);
- if (gms) {
- STAT(gms_alloc);
- spin_lock_init(&gms->ms_asid_lock);
- gms->ms_notifier.ops = &gru_mmuops;
- atomic_set(&gms->ms_refcnt, 1);
- init_waitqueue_head(&gms->ms_wait_queue);
- err = __mmu_notifier_register(&gms->ms_notifier, current->mm);
- if (err)
- goto error;
- }
+ if (!gms)
+ return ERR_PTR(-ENOMEM);
+ STAT(gms_alloc);
+ spin_lock_init(&gms->ms_asid_lock);
+ gms->ms_notifier.ops = &gru_mmuops;
+ atomic_set(&gms->ms_refcnt, 1);
+ init_waitqueue_head(&gms->ms_wait_queue);
+ err = __mmu_notifier_register(&gms->ms_notifier, current->mm);
+ if (err)
+ goto error;
}
if (gms)
gru_dbg(grudev, "gms %p, refcnt %d\n", gms,
--
1.9.1