[PATCH] mm: Export follow_pte() for KVM so that KVM can stop using follow_pfn()

From: Sean Christopherson
Date: Thu Feb 04 2021 - 12:19:08 EST


Export follow_pte() to fix build breakage when KVM is built as a module.
An in-flight KVM fix switches from follow_pfn() to follow_pte() in order
to grab the page protections along with the PFN.

Fixes: bd2fae8da794 ("KVM: do not assume PTE is writable after follow_pfn")
Cc: David Stevens <stevensd@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: kvm@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---

Paolo, maybe you can squash this with the appropriate acks?

mm/memory.c | 1 +
1 file changed, 1 insertion(+)

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
--
2.30.0.365.g02bc693789-goog