This is a note to let you know that I've just added the patch titled
powerpc/mm/altmap: Fix altmap boundary check
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-mm-altmap-fix-altmap-boundary-check.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 462bc16051f514bb37a7f9e76bf95dc2f06866dc
Author: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Date: Mon Jul 24 23:43:20 2023 +0530
powerpc/mm/altmap: Fix altmap boundary check
[ 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@xxxxxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://msgid.link/20230724181320.471386-1-aneesh.kumar@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
index a5091c0347475..aff86679af961 100644
--- a/arch/powerpc/mm/init_64.c
+++ b/arch/powerpc/mm/init_64.c
@@ -266,8 +266,7 @@ 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);
