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Date:   Sat, 13 May 2023 18:37:52 +0900
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Ruihan Li <lrh2000@pku.edu.cn>
Cc:     Christoph Hellwig <hch@infradead.org>, linux-mm@kvack.org,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        Pasha Tatashin <pasha.tatashin@soleen.com>,
        David Hildenbrand <david@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 0/4] Fix type confusion in page_table_check
Message-ID: <2023051324-attentive-footwork-9dec@gregkh>
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On Fri, May 12, 2023 at 12:19:09AM +0800, Ruihan Li wrote:
> On Thu, May 11, 2023 at 08:32:01AM -0700, Christoph Hellwig wrote:
> > On Thu, May 11, 2023 at 09:44:55PM +0800, Ruihan Li wrote:
> > > Christoph's patch perfectly fixes _one_ problem: kmalloc'ed memory
> > > cannot be mapped to user space. However, as I detailed in the commit
> > > message, this series of patches fixes _three_ problems.
> > 
> > FYI, I agree with you.  My simple patch was sent before reading
> > your new series, and is a strict subset of it.
> 
> Thank you for the clarification.
> 
> > > I have to say that the original code is quite buggy. In the
> > > gen_pool_dma_alloc path, there is no guarantee of page alignment. 
> > 
> > I also find this whole interface very problematic to start with,
> > but that's a separate discussion for later.
> 
> Yes. I don't think hybrid allocation of DMA memory and normal memory in
> one function is a good thing, but currently there is no clear way to fix
> this. Mixing memory allocation and page allocation is another bad thing,
> and at least, my patch can (hopefully) solve the second (and much
> easier) issue.

Ok, I'll take these through the usb tree if I can get an ack for the
mm-specific patches.  Or were you going to send a v2 series?

thanks,

greg k-h