From cb7a5d58a9936f2a93648988cbaff2a34bd37c8d Mon Sep 17 00:00:00 2001 From: Sudarshan Rajagopalan Date: Wed, 22 Sep 2021 15:56:36 -0700 Subject: [PATCH] FROMLIST: arm64: mm: update max_pfn after memory hotplug After new memory blocks have been hotplugged, max_pfn and max_low_pfn needs updating to reflect on new PFNs being hot added to system. Without this patch, debug-related functions that use max_pfn such as get_max_dump_pfn() or read_page_owner() will not work with any page in memory that is hot-added after boot. Link: https://lore.kernel.org/lkml/cover.1632853776.git.quic_cgoldswo@quicinc.com/T/#md084740c6377eb12369bfe6eb8786f4689dc8498 Bug: 200171991 Fixes: 4ab215061554 ("arm64: Add memory hotplug support") Signed-off-by: Sudarshan Rajagopalan Signed-off-by: Chris Goldsworthy Acked-by: David Hildenbrand Cc: Florian Fainelli Cc: Georgi Djakov Change-Id: I1cb50889299957c871c498e19aa05778c7583c9d --- arch/arm64/mm/mmu.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 91a21d36d38c..c42c53e9e10c 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1506,6 +1506,11 @@ int arch_add_memory(int nid, u64 start, u64 size, if (ret) __remove_pgd_mapping(swapper_pg_dir, __phys_to_virt(start), size); + else { + max_pfn = PFN_UP(start + size); + max_low_pfn = max_pfn; + } + return ret; }