From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.bootlin.com (mail.bootlin.com [62.4.15.54]) by lists.ozlabs.org (Postfix) with ESMTP id 41xHlz00QyzDq5k for ; Fri, 24 Aug 2018 07:36:10 +1000 (AEST) From: Alexandre Belloni To: Li Yang Cc: Roy Pledge , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Alexandre Belloni Subject: [PATCH 1/2] soc: fsl: qbman: qman_portal: defer probing when qman is not available Date: Thu, 23 Aug 2018 23:35:59 +0200 Message-Id: <20180823213600.23426-1-alexandre.belloni@bootlin.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , If the qman driver (qman_ccsr) doesn't probe or fail to probe before qman_portal, qm_ccsr_start will be either NULL or a stale pointer to an unmapped page. This leads to a crash when probing qman_portal as the init_pcfg function calls qman_liodn_fixup that tries to read qman registers. Assume that qman didn't probe when the pool mask is 0. Signed-off-by: Alexandre Belloni --- drivers/soc/fsl/qbman/qman_portal.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/soc/fsl/qbman/qman_portal.c b/drivers/soc/fsl/qbman/qman_portal.c index a120002b630e..4fc80d2c8feb 100644 --- a/drivers/soc/fsl/qbman/qman_portal.c +++ b/drivers/soc/fsl/qbman/qman_portal.c @@ -277,6 +277,8 @@ static int qman_portal_probe(struct platform_device *pdev) } pcfg->pools = qm_get_pools_sdqcr(); + if (pcfg->pools == 0) + return -EPROBE_DEFER; spin_lock(&qman_lock); cpu = cpumask_next_zero(-1, &portal_cpus); -- 2.18.0