Commit 6072cf56 authored Oct 26, 2018 by Mike Rapoport Committed by Linus Torvalds Oct 26, 2018

of: ignore sub-page memory regions

Memory region size is rounded down to page boundary and with sub-page
region it becomes 0 and there is no point to add an empty region.
Moreover, when the base is less than PAGE_SIZE we get a bogus size as
(base + size - 1) evaluates to -1.

8cccffc5 ("of: check for size < 0 after rounding in
early_init_dt_add_memory_arch") introduced a test for wrap around for the
case when base is not page aligned, the same test can be used to ignore
sub-page region sizes.

Link: http://lkml.kernel.org/r/1533326330-31677-3-git-send-email-rppt@linux.vnet.ibm.com


Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 426dcd4b

drivers/of/fdt.c

+6 −5

Original line number	Diff line number	Diff line
		@@ -1127,12 +1127,13 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
		{
		const u64 phys_offset = MIN_MEMBLOCK_ADDR;

		if (!PAGE_ALIGNED(base)) {
		if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
		pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
		base, base + size);
		return;
		}

		if (!PAGE_ALIGNED(base)) {
		size -= PAGE_SIZE - (base & ~PAGE_MASK);
		base = PAGE_ALIGN(base);
		}

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