Hi Jens,
On 2019-01-16 18:49, Jens Axboe wrote:
[...]
+static void *io_mem_alloc(size_t size)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP
|
+ __GFP_NORETRY;
+
+ return (void *) __get_free_pages(gfp_flags, get_order(size));
Since these pages are shared between kernel and userspace, do we need
to care about d-cache aliasing on armv6 (or other "strange" archs
which I've never seen) with vivt or vipt cpu caches?
E.g. vmalloc_user() targets this problem by aligning kernel address
on SHMLBA, so no flush_dcache_page() is required.
--
Roman