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>>> set_page_refcounted(page); >>> + >>> + trace_mm_page_alloc(page, 0, gfp, ac.migratetype); >>> + kmsan_alloc_page(page, 0, gfp); >>> + >>> page_array[nr_populated++] = page; >>> } >>> >>> @@ -6911,6 +6915,12 @@ static void split_free_frozen_pages(struct list_head *list, gfp_t gfp_mask) >>> int i; >>> >>> post_alloc_hook(page, order, gfp_mask); >>> + /* >>> + * Initialize KMSAN state right after post_alloc_hook(). >>> + * This prepares the pages for subsequent outer callers >>> + * that might free sub-pages after the split. >>> + */ >>> + kmsan_alloc_page(page, order, gfp_mask); >>> if (!order) >>> continue; >>> >>> @@ -7117,6 +7127,9 @@ int alloc_contig_frozen_range_noprof(unsigned long start, unsigned long end, >>> >>> check_new_pages(head, order); >>> prep_new_page(head, order, gfp_mask, 0); >>> + >>> + trace_mm_page_alloc(page, order, gfp_mask, get_pageblock_migratetype(page)); >>> + kmsan_alloc_page(page, order, gfp_mask); >> There is no page defined in this function. Most probably you wanted >> to use head in place of page here. >> >> How did you compiled and tested this change? > Sorry, I just simply compiled with the change but add wrong code into > the commit. I can hardly make an environment that could trigger the same > warning here. I'm not sure if I can trigger syzbot to test this. Please try to send another version (v2) of this patch and then [1] follow instructions mentioned here. [1] https://github.com/google/syzkaller/blob/master/docs/syzbot.md#testing-patches >>> } else { >>> ret = -EINVAL; >>> WARN(true, "PFN range: requested [%lu, %lu), allocated [%lu, %lu)\n", >>> >>> --- >>> base-commit: bbeb83d3182abe0d245318e274e8531e5dd7a948 >>> change-id: 20260325-fix-kmsan-e291f752a949 >>> >>> Best regards, >> Thanks, >> Usama