On Tue, 28 Feb 2023 16:35:44 -0800 Peter Collingbourne pcc@google.com wrote:
This reverts commit 487a32ec24be819e747af8c2ab0d5c515508086a.
The should_skip_kasan_poison() function reads the PG_skip_kasan_poison flag from page->flags. However, this line of code in free_pages_prepare():
page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
clears most of page->flags, including PG_skip_kasan_poison, before calling should_skip_kasan_poison(), which meant that it would never return true as a result of the page flag being set. Therefore, fix the code to call should_skip_kasan_poison() before clearing the flags, as we were doing before the reverted patch.
What are the user visible effects of this change?
Cc: stable@vger.kernel.org # 6.1
Especially if it's cc:stable.
Thanks.