From: Aneesh Kumar K.V aneesh.kumar@linux.ibm.com
[ Upstream commit 6722b25712054c0f903b839b8f5088438dd04df3 ]
altmap->free includes the entire free space from which altmap blocks can be allocated. So when checking whether the kernel is doing altmap block free, compute the boundary correctly, otherwise memory hotunplug can fail.
Fixes: 9ef34630a461 ("powerpc/mm: Fallback to RAM if the altmap is unusable") Signed-off-by: "Aneesh Kumar K.V" aneesh.kumar@linux.ibm.com Reviewed-by: David Hildenbrand david@redhat.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://msgid.link/20230724181320.471386-1-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/mm/init_64.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c index e4fb5ab41e2d3..cfb97fabd5320 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -279,8 +279,7 @@ void __ref vmemmap_free(unsigned long start, unsigned long end, start = _ALIGN_DOWN(start, page_size); if (altmap) { alt_start = altmap->base_pfn; - alt_end = altmap->base_pfn + altmap->reserve + - altmap->free + altmap->alloc + altmap->align; + alt_end = altmap->base_pfn + altmap->reserve + altmap->free; }
pr_debug("vmemmap_free %lx...%lx\n", start, end);