linux-kernel - Re: [PATCH][next] dmaengine: dw-axi-dmac: remove redundant null check on desc

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

Message-ID: <20210208120907.GD879029@vkoul-mobl.Dlink>
Date:   Mon, 8 Feb 2021 17:39:07 +0530
From:   Vinod Koul <vkoul@...nel.org>
To:     "Sia, Jee Heng" <jee.heng.sia@...el.com>
Cc:     Colin King <colin.king@...onical.com>,
        Eugeniy Paltsev <Eugeniy.Paltsev@...opsys.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        "dmaengine@...r.kernel.org" <dmaengine@...r.kernel.org>,
        "kernel-janitors@...r.kernel.org" <kernel-janitors@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH][next] dmaengine: dw-axi-dmac: remove redundant null
 check on desc

On 04-02-21, 00:18, Sia, Jee Heng wrote:
> The code looks good to me. I have also verified it on Intel KeemBay platform.
> 
> Reviewed-by: Sia Jee Heng <jee.heng.sia@...el.com>
> Tested-by: Sia Jee Heng <jee.heng.sia@...el.com>

Please *do not* top post!

> 
> Thanks
> Regards
> Jee Heng
> > -----Original Message-----
> > From: Colin King <colin.king@...onical.com>
> > Sent: 03 February 2021 9:47 PM
> > To: Eugeniy Paltsev <Eugeniy.Paltsev@...opsys.com>; Vinod Koul
> > <vkoul@...nel.org>; Sia, Jee Heng <jee.heng.sia@...el.com>; Andy
> > Shevchenko <andriy.shevchenko@...ux.intel.com>;
> > dmaengine@...r.kernel.org
> > Cc: kernel-janitors@...r.kernel.org; linux-kernel@...r.kernel.org
> > Subject: [PATCH][next] dmaengine: dw-axi-dmac: remove redundant
> > null check on desc
> > 
> > From: Colin Ian King <colin.king@...onical.com>
> > 
> > The pointer desc is being null checked twice, the second null check is
> > redundant because desc has not been re-assigned between the checks.
> > Remove the redundant second null check on desc.
> > 
> > Addresses-Coverity: ("Logically dead code")
> > Fixes: ef6fb2d6f1ab ("dmaengine: dw-axi-dmac: simplify descriptor
> > management")
> > Signed-off-by: Colin Ian King <colin.king@...onical.com>
> > ---
> >  drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 4 ----
> >  1 file changed, 4 deletions(-)
> > 
> > diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > index ac3d81b72a15..d9e4ac3edb4e 100644
> > --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> > @@ -919,10 +919,6 @@ dma_chan_prep_dma_memcpy(struct
> > dma_chan *dchan, dma_addr_t dst_adr,
> >  		num++;
> >  	}
> > 
> > -	/* Total len of src/dest sg == 0, so no descriptor were
> > allocated */
> > -	if (unlikely(!desc))
> > -		return NULL;
> > -
> >  	/* Set end-of-link to the last link descriptor of list */
> >  	set_desc_last(&desc->hw_desc[num - 1]);
> >  	/* Managed transfer list */
> > --
> > 2.29.2
> 

-- 
~Vinod