Re: [PATCH 5.7 233/244] RISC-V: Acquire mmap lock before invoking walk_page_range

[gregkh@xxxxxxxxxxxxxxxxxxx]

On Mon, Jul 20, 2020 at 06:50:10PM +0000, Atish Patra wrote:
> On Mon, 2020-07-20 at 23:11 +0530, Naresh Kamboju wrote:
> > RISC-V build breaks on stable-rc 5.7 branch.
> > build failed with gcc-8, gcc-9 and gcc-9.
> > 
> 
> Sorry for the compilation issue.
> 
> mmap_read_lock was intrdouced in the following commit.
> 
> commit 9740ca4e95b4
> Author: Michel Lespinasse <walken@xxxxxxxxxx>
> Date:   Mon Jun 8 21:33:14 2020 -0700
> 
>     mmap locking API: initial implementation as rwsem wrappers
> 
> The following two commits replaced the usage of mmap_sem rwsem calls
> with mmap_lock.
> 
> d8ed45c5dcd4 (mmap locking API: use coccinelle to convert mmap_sem
> rwsem call sites)
> 89154dd5313f (mmap locking API: convert mmap_sem call sites missed by
> coccinelle)
> 
> The first commit is not present in stale 5.7-y for obvious reasons.
> 
> Do we need to send a separate patch only for stable branch with
> mmap_sem ? I am not sure if that will cause a conflict again in future.

I do not like taking odd backports, and would rather take the real patch
that is upstream.

I will drop this patch from the tree now, so everyone can figure out
what they want to do in the future :)

thanks,

greg k-h