This is a note to let you know that I've just added the patch titled powerpc/mm/dax: Fix the condition when checking if altmap vmemap can cross-boundary to the 5.10-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-dax-fix-the-condition-when-checking-if-al.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 77ce992044466d4b35641b1f2fb12da039ba5fc4 Author: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Date: Fri Jun 16 16:38:15 2023 +0530 powerpc/mm/dax: Fix the condition when checking if altmap vmemap can cross-boundary [ Upstream commit c8eebc4a99f15280654f23e914e746c40a516e50 ] Without this fix, the last subsection vmemmap can end up in memory even if the namespace is created with -M mem and has sufficient space in the altmap area. Fixes: cf387d9644d8 ("libnvdimm/altmap: Track namespace boundaries in altmap") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Tested-by: Sachin Sant <sachinp@xxxxxxxxxxxxx <mailto:sachinp@xxxxxxxxxxxxx>> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://msgid.link/20230616110826.344417-6-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 386be136026e8..b76cd49d521b9 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -188,7 +188,7 @@ static bool altmap_cross_boundary(struct vmem_altmap *altmap, unsigned long star unsigned long nr_pfn = page_size / sizeof(struct page); unsigned long start_pfn = page_to_pfn((struct page *)start); - if ((start_pfn + nr_pfn) > altmap->end_pfn) + if ((start_pfn + nr_pfn - 1) > altmap->end_pfn) return true; if (start_pfn < altmap->base_pfn)