[PATCH] mm: restore vm_normal_page check (315ab19a) · Commits · e / devices / android_kernel_xiaomi_markw

Hugh is rightly concerned that the CONFIG_DEBUG_VM coverage has gone too far in vm_normal_page, considering that we expect production kernels to be shipped with the option turned off, and that the code has been under some large changes recently. Signed-off-by:

Nick Piggin <npiggin@suse.de> Signed-off-by:

Linus Torvalds <torvalds@osdl.org>

mm/memory.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -395,12 +395,16 @@ struct page vm_normal_page(struct vm_area_struct vma, unsigned long addr, pte_
		return NULL;
		}

		#ifdef CONFIG_DEBUG_VM
		/*
		* Add some anal sanity checks for now. Eventually,
		* we should just do "return pfn_to_page(pfn)", but
		* in the meantime we check that we get a valid pfn,
		* and that the resulting page looks ok.
		*/
		if (unlikely(!pfn_valid(pfn))) {
		print_bad_pte(vma, pte, addr);
		return NULL;
		}
		#endif

		/*
		* NOTE! We still have PageReserved() pages in the page