linux-kernel - Re: Re: [PATCH] dmaengine: tegra20: Fix runtime PM imbalance in tegra_dma_issue

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <7c55cf68.45570.178b5bbe111.Coremail.dinghao.liu@zju.edu.cn>
Date:   Fri, 9 Apr 2021 16:24:52 +0800 (GMT+08:00)
From:   dinghao.liu@....edu.cn
To:     "Jon Hunter" <jonathanh@...dia.com>
Cc:     kjlu@....edu, "Laxman Dewangan" <ldewangan@...dia.com>,
        "Vinod Koul" <vkoul@...nel.org>,
        "Thierry Reding" <thierry.reding@...il.com>,
        dmaengine@...r.kernel.org, linux-tegra@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: Re: [PATCH] dmaengine: tegra20: Fix runtime PM imbalance in
 tegra_dma_issue_pending

> On 08/04/2021 08:11, Dinghao Liu wrote:
> > pm_runtime_get_sync() will increase the rumtime PM counter
> > even it returns an error. Thus a pairing decrement is needed
> > to prevent refcount leak. Fix this by replacing this API with
> > pm_runtime_resume_and_get(), which will not change the runtime
> > PM counter on error.
> > 
> > Signed-off-by: Dinghao Liu <dinghao.liu@....edu.cn>
> > ---
> >  drivers/dma/tegra20-apb-dma.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
> > index 71827d9b0aa1..73178afaf4c2 100644
> > --- a/drivers/dma/tegra20-apb-dma.c
> > +++ b/drivers/dma/tegra20-apb-dma.c
> > @@ -723,7 +723,7 @@ static void tegra_dma_issue_pending(struct dma_chan *dc)
> >  		goto end;
> >  	}
> >  	if (!tdc->busy) {
> > -		err = pm_runtime_get_sync(tdc->tdma->dev);
> > +		err = pm_runtime_resume_and_get(tdc->tdma->dev);
> >  		if (err < 0) {
> >  			dev_err(tdc2dev(tdc), "Failed to enable DMA\n");
> >  			goto end;
> > 
> 
> 
> Thanks! Looks like there are two instances of this that need fixing.
> 

Thanks for pointing out this! I will fix this and send a new patch soon.

Regards,
Dinghao