Re: [PATCH v3 1/6] binder: Fix selftest page indexing

[Tiffany Yang]

Kees Cook <kees@xxxxxxxxxx> writes:

> On Mon, Jul 14, 2025 at 11:53:14AM -0700, Tiffany Yang wrote:
> > The binder allocator selftest was only checking the last page of buffers
> > that ended on a page boundary. Correct the page indexing to account for
> > buffers that are not page-aligned.

> > Signed-off-by: Tiffany Yang <ynaffit@xxxxxxxxxx>
> > ---
> >   drivers/android/binder_alloc_selftest.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)

> > diff --git a/drivers/android/binder_alloc_selftest.c  
> > b/drivers/android/binder_alloc_selftest.c
> > index c88735c54848..486af3ec3c02 100644
> > --- a/drivers/android/binder_alloc_selftest.c
> > +++ b/drivers/android/binder_alloc_selftest.c
> > @@ -142,12 +142,12 @@ static void binder_selftest_free_buf(struct  
> > binder_alloc *alloc,
> >   	for (i = 0; i < BUFFER_NUM; i++)
> >   		binder_alloc_free_buf(alloc, buffers[seq[i]]);

> > -	for (i = 0; i < end / PAGE_SIZE; i++) {
> >   		/**
> >   		 * Error message on a free page can be false positive
> >   		 * if binder shrinker ran during binder_alloc_free_buf
> >   		 * calls above.
> >   		 */
> > +	for (i = 0; i <= (end - 1) / PAGE_SIZE; i++) {

> Nit: this comment is now not aligned correctly. Probably the best would
> be the leave the "for" line above the comment.

> -Kees


Thank you for catching this! Will be fixed in v4.

> >   		if (list_empty(page_to_lru(alloc->pages[i]))) {
> >   			pr_err_size_seq(sizes, seq);
> >   			pr_err("expect lru but is %s at page index %d\n",
> > --
> > 2.50.0.727.gbf7dc18ff4-goog


--
Tiffany Y. Yang