x86 PAT: remove PFNMAP type on track_pfn_vma_new() error
Impact: fix (harmless) double-free of memtype entries and avoid warning
On track_pfn_vma_new() failure, reset the vm_flags so that there will be
no second cleanup happening when upper level routines call unmap_vmas().
This patch fixes part of the bug reported here:
http://marc.info/?l=linux-kernel&m=123108883716357&w=2
Specifically the error message:
X:5010 freeing invalid memtype d0000000-d0101000
Is due to multiple frees on error path, will not happen with the patch below.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/mm/memory.c b/mm/memory.c
index c2d4c47..d3ee2ea 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1672,8 +1672,14 @@
vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
err = track_pfn_vma_new(vma, prot, pfn, PAGE_ALIGN(size));
- if (err)
+ if (err) {
+ /*
+ * To indicate that track_pfn related cleanup is not
+ * needed from higher level routine calling unmap_vmas
+ */
+ vma->vm_flags &= ~(VM_IO | VM_RESERVED | VM_PFNMAP);
return -EINVAL;
+ }
BUG_ON(addr >= end);
pfn -= addr >> PAGE_SHIFT;