From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753086AbbC3QrU (ORCPT ); Mon, 30 Mar 2015 12:47:20 -0400 Received: from mail-ig0-f170.google.com ([209.85.213.170]:37914 "EHLO mail-ig0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752752AbbC3QrS (ORCPT ); Mon, 30 Mar 2015 12:47:18 -0400 MIME-Version: 1.0 In-Reply-To: <1427414105-3480-1-git-send-email-sbranden@broadcom.com> References: <1427414105-3480-1-git-send-email-sbranden@broadcom.com> Date: Mon, 30 Mar 2015 22:17:17 +0530 Message-ID: Subject: Re: [PATCH] dmaengine: pl330: fix the race condition in pl330 driver. From: Jassi Brar To: Scott Branden Cc: Dan Williams , Vinod Koul , Linux Kernel Mailing List , ismail , Anatol Pomazao , Dmitry Torokhov , bcm-kernel-feedback-list@broadcom.com, "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 27, 2015 at 5:25 AM, Scott Branden wrote: > From: ismail > > Update the thread running index before issuing the > GO command to the DMAC. > > Tested-by: Mohamed Ismail Abdul Packir Mohamed > Reviewed-by: Ray Jui > Reviewed-by: Arun Parameswaran > Reviewed-by: Scott Branden > Signed-off-by: Scott Branden > Signed-off-by: Mohamed Ismail Abdul Packir Mohamed > --- > drivers/dma/pl330.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c > index 0e1f567..631642d 100644 > --- a/drivers/dma/pl330.c > +++ b/drivers/dma/pl330.c > @@ -1072,11 +1072,11 @@ static bool _trigger(struct pl330_thread *thrd) > /* Set to generate interrupts for SEV */ > writel(readl(regs + INTEN) | (1 << thrd->ev), regs + INTEN); > > + thrd->req_running = idx; > + > /* Only manager can execute GO */ > _execute_DBGINSN(thrd, insn, true); > > - thrd->req_running = idx; > - It would help to know what the behavior looks like before and after the patch. If anything we should look at locking rather the reordering. Thanks From mboxrd@z Thu Jan 1 00:00:00 1970 From: jassisinghbrar@gmail.com (Jassi Brar) Date: Mon, 30 Mar 2015 22:17:17 +0530 Subject: [PATCH] dmaengine: pl330: fix the race condition in pl330 driver. In-Reply-To: <1427414105-3480-1-git-send-email-sbranden@broadcom.com> References: <1427414105-3480-1-git-send-email-sbranden@broadcom.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Mar 27, 2015 at 5:25 AM, Scott Branden wrote: > From: ismail > > Update the thread running index before issuing the > GO command to the DMAC. > > Tested-by: Mohamed Ismail Abdul Packir Mohamed > Reviewed-by: Ray Jui > Reviewed-by: Arun Parameswaran > Reviewed-by: Scott Branden > Signed-off-by: Scott Branden > Signed-off-by: Mohamed Ismail Abdul Packir Mohamed > --- > drivers/dma/pl330.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c > index 0e1f567..631642d 100644 > --- a/drivers/dma/pl330.c > +++ b/drivers/dma/pl330.c > @@ -1072,11 +1072,11 @@ static bool _trigger(struct pl330_thread *thrd) > /* Set to generate interrupts for SEV */ > writel(readl(regs + INTEN) | (1 << thrd->ev), regs + INTEN); > > + thrd->req_running = idx; > + > /* Only manager can execute GO */ > _execute_DBGINSN(thrd, insn, true); > > - thrd->req_running = idx; > - It would help to know what the behavior looks like before and after the patch. If anything we should look at locking rather the reordering. Thanks