drivers/misc/sgi-gru: fix dereference of ERR_PTR

gru_alloc_gts() can fail and it can return ERR_PTR(errvalue). We should
not dereference it if it has returned error. And incase it has returned
error then wait for some time and try again.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Acked-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index 490b79a27c882cec8b569fc213b4339e0bd604b6..7812e34a111274962f4720fad68f053f9149c0f5 100644 (file)
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -160,7 +160,12 @@ static void gru_load_kernel_context(struct gru_blade_state *bs, int blade_id)
        down_write(&bs->bs_kgts_sema);
 
        if (!bs->bs_kgts) {
-               bs->bs_kgts = gru_alloc_gts(NULL, 0, 0, 0, 0, 0);
+               do {
+                       bs->bs_kgts = gru_alloc_gts(NULL, 0, 0, 0, 0, 0);
+                       if (!IS_ERR(bs->bs_kgts))
+                               break;
+                       msleep(1);
+               } while (true);
                bs->bs_kgts->ts_user_blade_id = blade_id;
        }
        kgts = bs->bs_kgts;