[PATCH 4.4 31/43] mm: fix cache mode tracking in vm_insert_mixed()

From: Greg Kroah-Hartman
Date: Tue Aug 14 2018 - 13:47:22 EST

4.4-stable review patch. If anyone has any objections, please let me know.


From: Dan Williams <dan.j.williams@xxxxxxxxx>

commit 87744ab3832b83ba71b931f86f9cfdb000d07da5 upstream

vm_insert_mixed() unlike vm_insert_pfn_prot() and vmf_insert_pfn_pmd(),
fails to check the pgprot_t it uses for the mapping against the one
recorded in the memtype tracking tree. Add the missing call to
track_pfn_insert() to preclude cases where incompatible aliased mappings
are established for a given physical address range.

[groeck: Backport to v4.4.y]

Link: http://lkml.kernel.org/r/147328717909.35069.14256589123570653697.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
Cc: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
mm/memory.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1654,10 +1654,14 @@ EXPORT_SYMBOL(vm_insert_pfn_prot);
int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn)
+ pgprot_t pgprot = vma->vm_page_prot;
BUG_ON(!(vma->vm_flags & VM_MIXEDMAP));

if (addr < vma->vm_start || addr >= vma->vm_end)
return -EFAULT;
+ if (track_pfn_insert(vma, &pgprot, pfn))
+ return -EINVAL;

* If we don't have pte special, then we have to use the pfn_valid()
@@ -1670,9 +1674,9 @@ int vm_insert_mixed(struct vm_area_struc
struct page *page;

page = pfn_to_page(pfn);
- return insert_page(vma, addr, page, vma->vm_page_prot);
+ return insert_page(vma, addr, page, pgprot);
- return insert_pfn(vma, addr, pfn, vma->vm_page_prot);
+ return insert_pfn(vma, addr, pfn, pgprot);