Re: [PATCH 0/4] Fix type confusion in page_table_check

[Ruihan Li]

On Sat, May 13, 2023 at 06:37:52PM +0900, Greg Kroah-Hartman wrote:
> 
> 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

There are some comments from Alan and David, so I'll send a v2 series to
address them (probably tomorrow).

Thanks,
Ruihan Li