From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932102AbbIDE0b (ORCPT ); Fri, 4 Sep 2015 00:26:31 -0400 Received: from mail-pa0-f50.google.com ([209.85.220.50]:34098 "EHLO mail-pa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795AbbIDE0a (ORCPT ); Fri, 4 Sep 2015 00:26:30 -0400 From: Sudip Mukherjee To: Dimitri Sivanich , Arnd Bergmann , Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, Sudip Mukherjee Subject: [PATCH v3] drivers/misc/sgi-gru: fix dereference of ERR_PTR Date: Fri, 4 Sep 2015 09:56:20 +0530 Message-Id: <1441340780-5634-1-git-send-email-sudipm.mukherjee@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1441291851-29411-4-git-send-email-sudipm.mukherjee@gmail.com> References: <1441291851-29411-4-git-send-email-sudipm.mukherjee@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- v3: compact code for if logic v2: on error retry after msleep(1). v1: returned error. drivers/misc/sgi-gru/grukservices.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c index 490b79a..7812e34 100644 --- 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; -- 1.9.1