Subject: Re: linux-next: build failure after merge of the kvm tree

From: Paolo Bonzini <[email-masked]>
Date: Fri, 5 Feb 2021 11:08:39 +0100

On 05/02/21 06:02, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the kvm tree, today's linux-next build (powerpc
> ppc64_defconfig) failed like this:
> 
> ERROR: modpost: ".follow_pte" [arch/powerpc/kvm/kvm.ko] undefined!
> 
> Caused by commit
> 
>    bd2fae8da794 ("KVM: do not assume PTE is writable after follow_pfn")
> 
> follow_pte is not EXPORTed.
> 
> I have used the kvm tree from next-20210204 for today.
> 

Stephen, can you squash in the following for the time being?

diff --git a/mm/memory.c b/mm/memory.c
index feff48e1465a..15cbd10afd59 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4775,6 +4775,7 @@ int follow_pte(struct mm_struct *mm, unsigned long 
address,
  out:
  	return -EINVAL;
  }
+EXPORT_SYMBOL_GPL(follow_pte);

  /**
   * follow_pfn - look up PFN at a user virtual address

A similar patch has been posted already, but Jason Gunthorpe asked to 
add some kerneldoc comments.  Therefore it will not be in kvm/next for a 
few more days.

Paolo