linux-kernel - Re: [PATCH 04/25] dmaengine: Fix dma_slave_config.dst

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: <20220331105031.GA104799@thinkpad>
Date:   Thu, 31 Mar 2022 16:20:31 +0530
From:   Manivannan Sadhasivam <manivannan.sadhasivam@...aro.org>
To:     Serge Semin <fancer.lancer@...il.com>
Cc:     Vinod Koul <vkoul@...nel.org>,
        Serge Semin <Sergey.Semin@...kalelectronics.ru>,
        Gustavo Pimentel <gustavo.pimentel@...opsys.com>,
        Jingoo Han <jingoohan1@...il.com>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Frank Li <Frank.Li@....com>,
        Alexey Malahov <Alexey.Malahov@...kalelectronics.ru>,
        Pavel Parkhomenko <Pavel.Parkhomenko@...kalelectronics.ru>,
        Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
        Rob Herring <robh@...nel.org>,
        Krzysztof Wilczyński <kw@...ux.com>,
        linux-pci@...r.kernel.org, dmaengine@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 04/25] dmaengine: Fix dma_slave_config.dst_addr
 description

On Thu, Mar 31, 2022 at 10:13:43AM +0300, Serge Semin wrote:
> On Thu, Mar 31, 2022 at 11:08:06AM +0530, Vinod Koul wrote:
> > On 24-03-22, 19:38, Manivannan Sadhasivam wrote:
> > > On Thu, Mar 24, 2022 at 04:48:15AM +0300, Serge Semin wrote:
> > > > Most likely due to a copy-paste mistake the dst_addr member of the
> > > > dma_slave_config structure has been marked as ignored if the !source!
> > > > address belong to the memory. That is relevant to the src_addr field of
> > > > the structure while the dst_addr field as containing a destination device
> > > > address is supposed to be ignored if the destination is the CPU memory.
> > > > Let's fix the field description accordingly.
> > > > 
> > > > Signed-off-by: Serge Semin <Sergey.Semin@...kalelectronics.ru>
> > > 
> > > Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@...aro.org>
> > > 
> > > One suggestion below.
> > > 
> > > > ---
> > > >  include/linux/dmaengine.h | 2 +-
> > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > > 
> > > > diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> > > > index 842d4f7ca752..f204ea16ac1c 100644
> > > > --- a/include/linux/dmaengine.h
> > > > +++ b/include/linux/dmaengine.h
> > > > @@ -395,7 +395,7 @@ enum dma_slave_buswidth {
> > > >   * should be read (RX), if the source is memory this argument is
> > > >   * ignored.
> > > >   * @dst_addr: this is the physical address where DMA slave data
> > > > - * should be written (TX), if the source is memory this argument
> > > > + * should be written (TX), if the destination is memory this argument
> > >
>  
> > > Should we rename "memory" to "local memory" or something similar?
> > 
> > what do you mean by local memory :)
> 
> Most likely Manivannan just confused the whole eDMA device specifics
> with this patch purpose. This commit has nothing to do with "local"
> and "remote" device memory. Such definitions are relevant to the DW
> eDMA setups (whether device is integrated into the PCIe Host/End-point
> controller then the CPU memory is a local memory for it, or it's a
> remote PCI End-point, then the CPU memory is a remote memory for it).
> 

Ah, yes indeed. While I was reviewing the eDMA patches I just went with that
context. Sorry for the noise.

Thanks,
Mani

> Guys. Regarding the patchsets review procedure. I notice all the
> comments. Just didn't have time to respond so far. Will do that till
> the end of the week.
> 
> -Sergey
> 
> > 
> > -- 
> > ~Vinod