This is a note to let you know that I've just added the patch titled
selftests: mm: fix map_hugetlb failure on 64K page size systems
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
selftests-mm-fix-map_hugetlb-failure-on-64k-page-size-systems.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 91b80cc5b39f00399e8e2d17527cad2c7fa535e2 Mon Sep 17 00:00:00 2001
From: Nico Pache <npache@xxxxxxxxxx>
Date: Fri, 19 Jan 2024 06:14:29 -0700
Subject: selftests: mm: fix map_hugetlb failure on 64K page size systems
From: Nico Pache <npache@xxxxxxxxxx>
commit 91b80cc5b39f00399e8e2d17527cad2c7fa535e2 upstream.
On systems with 64k page size and 512M huge page sizes, the allocation and
test succeeds but errors out at the munmap. As the comment states, munmap
will failure if its not HUGEPAGE aligned. This is due to the length of
the mapping being 1/2 the size of the hugepage causing the munmap to not
be hugepage aligned. Fix this by making the mapping length the full
hugepage if the hugepage is larger than the length of the mapping.
Link: https://lkml.kernel.org/r/20240119131429.172448-1-npache@xxxxxxxxxx
Signed-off-by: Nico Pache <npache@xxxxxxxxxx>
Cc: Donet Tom <donettom@xxxxxxxxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/mm/map_hugetlb.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/tools/testing/selftests/mm/map_hugetlb.c
+++ b/tools/testing/selftests/mm/map_hugetlb.c
@@ -15,6 +15,7 @@
#include <unistd.h>
#include <sys/mman.h>
#include <fcntl.h>
+#include "vm_util.h"
#define LENGTH (256UL*1024*1024)
#define PROTECTION (PROT_READ | PROT_WRITE)
@@ -58,10 +59,16 @@ int main(int argc, char **argv)
{
void *addr;
int ret;
+ size_t hugepage_size;
size_t length = LENGTH;
int flags = FLAGS;
int shift = 0;
+ hugepage_size = default_huge_page_size();
+ /* munmap with fail if the length is not page aligned */
+ if (hugepage_size > length)
+ length = hugepage_size;
+
if (argc > 1)
length = atol(argv[1]) << 20;
if (argc > 2) {
Patches currently in stable-queue which might be from npache@xxxxxxxxxx are
queue-6.6/selftests-mm-fix-map_hugetlb-failure-on-64k-page-size-systems.patch
