On Tue, Mar 30, 2021 at 12:07 AM Vlastimil Babka <vbabka@xxxxxxx> wrote: > > On 3/30/21 12:00 AM, Andrey Konovalov wrote: > > On Mon, Mar 29, 2021 at 2:10 PM Vlastimil Babka <vbabka@xxxxxxx> wrote: > >> > >> > commit 855a9c4018f3219db8be7e4b9a65ab22aebfde82 > >> > Author: Andrey Konovalov <andreyknvl@xxxxxxxxx> > >> > Date: Thu Mar 18 17:01:40 2021 +1100 > >> > > >> > kasan, mm: integrate page_alloc init with HW_TAGS > >> > >> But the mmotm patch/-next commit also changes post_alloc_hook() > >> > >> Before the patch it was: > >> kernel_unpoison_pages(page, 1 << order); > >> ... > >> kernel_init_free_pages(page, 1 << order); > >> > >> Now it is (for !kasan_has_integrated_init()): > >> > >> kernel_init_free_pages(page, 1 << order); > >> > >> kernel_unpoison_pages(page, 1 << order); > >> > >> That has to be wrong, because we init the page with zeroes and then call > >> kernel_unpoison_pages() which checks for the 0xaa pattern. Andrey? > > > > It's similar to free_pages_prepare(): kernel_unpoison_pages() and > > want_init_on_alloc() are exclusive, so the order shouldn't matter. Am > > I missing something? > > Yeah, when the allocation has __GFP_ZERO, want_init_on_alloc() will return true > even with the static branches disabled. Ah, I see. I'll post a fix soon. Thank you!
