Anshuman Khandual 475a4307c1 arm64/mm: Fix pfn_valid() for ZONE_DEVICE based memory ... [ Upstream commit eeb0753ba2 ] pfn_valid() validates a pfn but basically it checks for a valid struct page backing for that pfn. It should always return positive for memory ranges backed with struct page mapping. But currently pfn_valid() fails for all ZONE_DEVICE based memory types even though they have struct page mapping. pfn_valid() asserts that there is a memblock entry for a given pfn without MEMBLOCK_NOMAP flag being set. The problem with ZONE_DEVICE based memory is that they do not have memblock entries. Hence memblock_is_map_memory() will invariably fail via memblock_search() for a ZONE_DEVICE based address. This eventually fails pfn_valid() which is wrong. memblock_is_map_memory() needs to be skipped for such memory ranges. As ZONE_DEVICE memory gets hotplugged into the system via memremap_pages() called from a driver, their respective memory sections will not have SECTION_IS_EARLY set. Normal hotplug memory will never have MEMBLOCK_NOMAP set in their memblock regions. Because the flag MEMBLOCK_NOMAP was specifically designed and set for firmware reserved memory regions. memblock_is_map_memory() can just be skipped as its always going to be positive and that will be an optimization for the normal hotplug memory. Like ZONE_DEVICE based memory, all normal hotplugged memory too will not have SECTION_IS_EARLY set for their sections Skipping memblock_is_map_memory() for all non early memory sections would fix pfn_valid() problem for ZONE_DEVICE based memory and also improve its performance for normal hotplug memory as well. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Acked-by: David Hildenbrand <david@redhat.com> Fixes: 73b20c84d4 ("arm64: mm: implement pte_devmap support") Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/1614921898-4099-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-03-17 17:06:33 +01:00
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boot	Revert "arm64: dts: amlogic: add missing ethernet reset ID"	2021-03-09 11:11:15 +01:00
configs	arm64: defconfig: Build in CONFIG_GPIO_MXC by default	2020-10-26 15:48:58 +08:00
crypto	crypto: arm64/sha - add missing module aliases	2021-03-04 11:38:31 +01:00
include	arm64: mte: Map hotplugged memory as Normal Tagged	2021-03-17 17:06:28 +01:00
kernel	arm64: perf: Fix 64-bit event counter read truncation	2021-03-17 17:06:28 +01:00
kvm	KVM: arm64: Filter out v8.1+ events on v8.0 HW	2021-02-03 23:28:41 +01:00
lib	arm64: Change .weak to SYM_FUNC_START_WEAK_PI for arch/arm64/lib/mem*.S	2020-10-30 08:32:31 +00:00
mm	arm64/mm: Fix pfn_valid() for ZONE_DEVICE based memory	2021-03-17 17:06:33 +01:00
net	arm64: bpf: Fix branch offset in JIT	2020-09-17 12:05:36 +01:00
xen
Kbuild
Kconfig	arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+	2021-03-11 14:17:22 +01:00
Kconfig.debug	arm64: remove TEXT_OFFSET randomization	2020-06-15 13:10:59 +01:00
Kconfig.platforms	arm64: berlin: Select DW_APB_TIMER_OF	2020-10-26 10:45:03 +01:00
Makefile	arm64: link with -z norelro for LLD or aarch64-elf	2021-01-12 20:18:24 +01:00