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Learn why this is important at https://aka.ms/ >> LearnAboutSenderIdentification ] >> [...] >>>>   mm/page_alloc.c | 19 +++++++++++++++++-- >>>>   1 file changed, 17 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >>>> index b1c5430cad4e..178cbebadd50 100644 >>>> --- a/mm/page_alloc.c >>>> +++ b/mm/page_alloc.c >>>> @@ -1224,8 +1224,23 @@ static void kernel_init_pages(struct page >>>> *page, int numpages) >>>> >>>>        /* s390's use of memset() could override KASAN redzones. */ >>>>        kasan_disable_current(); >>>> -     for (i = 0; i < numpages; i++) >>>> -             clear_highpage_kasan_tagged(page + i); >>>> + >>>> +     if (!IS_ENABLED(CONFIG_HIGHMEM)) { >>>> +             void *addr = kasan_reset_tag(page_address(page)); >>>> +             unsigned int unit = preempt_model_preemptible() ? >>>> +                                     numpages : >>>> PROCESS_PAGES_NON_PREEMPT_BATCH; >>>> +             int count; >>>> + >>>> +             for (i = 0; i < numpages; i += count) { >>>> +                     cond_resched(); > > Just thinking, > Considering that for preemptible kernel/preempt_auto preempt_count() > knows about preemption points to decide where it can preempt, > > and > > for non_preemptible kernel and voluntary kernel it is safe to do > preemption at PROCESS_PAGES_NON_PREEMPT_BATCH granularity s/preemption/clear_page/ > do we need cond_resched() here ? > > Let me know if I am missing something. > I do see Andrew also has same thoughts, (to remove cond_resched() and sorry for being not crisp :)) But please ensure you test with the below configs to ensure there are no surprises viz., preempt=none,voluntary,full(/auto). Regards - Raghu