This is a note to let you know that I've just added the patch titled
iommufd/selftest: Fix dirty bitmap tests with u8 bitmaps
to the 6.10-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:
iommufd-selftest-fix-dirty-bitmap-tests-with-u8-bitm.patch
and it can be found in the queue-6.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e07392b398c932af48386141d5182b6ad9331000
Author: Joao Martins <joao.m.martins@xxxxxxxxxx>
Date: Thu Jun 27 12:00:55 2024 +0100
iommufd/selftest: Fix dirty bitmap tests with u8 bitmaps
[ Upstream commit ec61f820a2ff07d1717583bd57d6ee45d2763a6e ]
With 64k base pages, the first 128k iova length test requires less than a
byte for a bitmap, exposing a bug in the tests that assume that bitmaps are
at least a byte.
Rather than dealing with bytes, have _test_mock_dirty_bitmaps() pass the
number of bits. The caller functions are adjusted to also use bits as well,
and converting to bytes when clearing, allocating and freeing the bitmap.
Link: https://lore.kernel.org/r/20240627110105.62325-2-joao.m.martins@xxxxxxxxxx
Reported-by: Matt Ochs <mochs@xxxxxxxxxx>
Fixes: a9af47e382a4 ("iommufd/selftest: Test IOMMU_HWPT_GET_DIRTY_BITMAP")
Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Tested-by: Matt Ochs <mochs@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index edf1c99c9936c..0b04d782a19fc 100644
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -1722,6 +1722,7 @@ FIXTURE_VARIANT(iommufd_dirty_tracking)
FIXTURE_SETUP(iommufd_dirty_tracking)
{
+ unsigned long size;
int mmap_flags;
void *vrc;
int rc;
@@ -1749,12 +1750,11 @@ FIXTURE_SETUP(iommufd_dirty_tracking)
assert(vrc == self->buffer);
self->page_size = MOCK_PAGE_SIZE;
- self->bitmap_size =
- variant->buffer_size / self->page_size / BITS_PER_BYTE;
+ self->bitmap_size = variant->buffer_size / self->page_size;
/* Provision with an extra (PAGE_SIZE) for the unaligned case */
- rc = posix_memalign(&self->bitmap, PAGE_SIZE,
- self->bitmap_size + PAGE_SIZE);
+ size = DIV_ROUND_UP(self->bitmap_size, BITS_PER_BYTE);
+ rc = posix_memalign(&self->bitmap, PAGE_SIZE, size + PAGE_SIZE);
assert(!rc);
assert(self->bitmap);
assert((uintptr_t)self->bitmap % PAGE_SIZE == 0);
@@ -1775,7 +1775,7 @@ FIXTURE_SETUP(iommufd_dirty_tracking)
FIXTURE_TEARDOWN(iommufd_dirty_tracking)
{
munmap(self->buffer, variant->buffer_size);
- munmap(self->bitmap, self->bitmap_size);
+ munmap(self->bitmap, DIV_ROUND_UP(self->bitmap_size, BITS_PER_BYTE));
teardown_iommufd(self->fd, _metadata);
}
diff --git a/tools/testing/selftests/iommu/iommufd_utils.h b/tools/testing/selftests/iommu/iommufd_utils.h
index 8d2b46b2114da..c612fbf0195ba 100644
--- a/tools/testing/selftests/iommu/iommufd_utils.h
+++ b/tools/testing/selftests/iommu/iommufd_utils.h
@@ -22,6 +22,8 @@
#define BIT_MASK(nr) (1UL << ((nr) % __BITS_PER_LONG))
#define BIT_WORD(nr) ((nr) / __BITS_PER_LONG)
+#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
+
static inline void set_bit(unsigned int nr, unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
@@ -346,12 +348,12 @@ static int _test_cmd_mock_domain_set_dirty(int fd, __u32 hwpt_id, size_t length,
static int _test_mock_dirty_bitmaps(int fd, __u32 hwpt_id, size_t length,
__u64 iova, size_t page_size,
size_t pte_page_size, __u64 *bitmap,
- __u64 bitmap_size, __u32 flags,
+ __u64 nbits, __u32 flags,
struct __test_metadata *_metadata)
{
unsigned long npte = pte_page_size / page_size, pteset = 2 * npte;
- unsigned long nbits = bitmap_size * BITS_PER_BYTE;
unsigned long j, i, nr = nbits / pteset ?: 1;
+ unsigned long bitmap_size = DIV_ROUND_UP(nbits, BITS_PER_BYTE);
__u64 out_dirty = 0;
/* Mark all even bits as dirty in the mock domain */
