From patchwork Fri Dec 21 14:41:42 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Madalin Bucur X-Patchwork-Id: 1017552 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 43LrwF5ZgWz9sCr for ; Sat, 22 Dec 2018 01:43:25 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=nxp.com Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43LrwF4FxXzDrB3 for ; Sat, 22 Dec 2018 01:43:25 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=nxp.com X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nxp.com (client-ip=92.121.34.21; helo=inva021.nxp.com; envelope-from=madalin.bucur@nxp.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=nxp.com Received: from inva021.nxp.com (inva021.nxp.com [92.121.34.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43LrtQ3M7rzDqv2 for ; Sat, 22 Dec 2018 01:41:48 +1100 (AEDT) Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 469862004DE; Fri, 21 Dec 2018 15:41:45 +0100 (CET) Received: from inva024.eu-rdc02.nxp.com (inva024.eu-rdc02.nxp.com [134.27.226.22]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 3A353200023; Fri, 21 Dec 2018 15:41:45 +0100 (CET) Received: from fsr-fed2164-101.ea.freescale.net (fsr-fed2164-101.ea.freescale.net [10.171.82.91]) by inva024.eu-rdc02.nxp.com (Postfix) with ESMTP id D0D50205E9; Fri, 21 Dec 2018 15:41:44 +0100 (CET) From: Madalin Bucur To: leoyang.li@nxp.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH] soc: fsl: qbman: avoid race in clearing QMan interrupt Date: Fri, 21 Dec 2018 16:41:42 +0200 Message-Id: <1545403302-22475-1-git-send-email-madalin.bucur@nxp.com> X-Mailer: git-send-email 2.1.0 X-Virus-Scanned: ClamAV using ClamSMTP X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: madalin.bucur@nxp.com Cc: Madalin Bucur , netdev@vger.kernel.org, roy.pledge@nxp.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, davem@davemloft.net Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" By clearing all interrupt sources, not only those that already occurred, the existing code may acknowledge by mistake interrupts that occurred after the code checks for them. Signed-off-by: Madalin Bucur Signed-off-by: Roy Pledge --- drivers/soc/fsl/qbman/qman.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/soc/fsl/qbman/qman.c b/drivers/soc/fsl/qbman/qman.c index 52c153cd795a..636f83f781f5 100644 --- a/drivers/soc/fsl/qbman/qman.c +++ b/drivers/soc/fsl/qbman/qman.c @@ -1143,18 +1143,19 @@ static void qm_mr_process_task(struct work_struct *work); static irqreturn_t portal_isr(int irq, void *ptr) { struct qman_portal *p = ptr; - - u32 clear = QM_DQAVAIL_MASK | p->irq_sources; u32 is = qm_in(&p->p, QM_REG_ISR) & p->irq_sources; + u32 clear = 0; if (unlikely(!is)) return IRQ_NONE; /* DQRR-handling if it's interrupt-driven */ - if (is & QM_PIRQ_DQRI) + if (is & QM_PIRQ_DQRI) { __poll_portal_fast(p, QMAN_POLL_LIMIT); + clear = QM_DQAVAIL_MASK | QM_PIRQ_DQRI; + } /* Handling of anything else that's interrupt-driven */ - clear |= __poll_portal_slow(p, is); + clear |= __poll_portal_slow(p, is) & QM_PIRQ_SLOW; qm_out(&p->p, QM_REG_ISR, clear); return IRQ_HANDLED; }