[PATCH] mm: thp: fix a double unlock bug

From: Dan Carpenter
Date: Tue Jun 01 2021 - 05:24:33 EST


We're supposed to be holding the "vmf->ptl" spin_lock when we goto
out_map. The lock is dropped after if finishes cleaning up.

Fixes: 9aff7b33c74a ("mm: thp: refactor NUMA fault handling")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
mm/huge_memory.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index e353bbc6cee3..caa0148f15bb 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1465,10 +1465,8 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)

pmd = pmd_modify(oldpmd, vma->vm_page_prot);
page = vm_normal_page_pmd(vma, haddr, pmd);
- if (!page) {
- spin_unlock(vmf->ptl);
+ if (!page)
goto out_map;
- }

/* See similar comment in do_numa_page for explanation */
if (!was_writable)
--
2.30.2