x86/mm: Fix marking of unused sub-pmd ranges

The unused part precedes the new range spanned by the start, end parameters
of vmemmap_use_new_sub_pmd(). This means it actually goes from
ALIGN_DOWN(start, PMD_SIZE) up to start.

Use the correct address when applying the mark using memset.

Fixes: 8d400913c2 ("x86/vmemmap: handle unpopulated sub-pmd ranges")
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220509090637.24152-2-ken@codelabs.ch
This commit is contained in:
Adrian-Ken Rueegsegger 2022-05-09 11:06:37 +02:00 committed by Thomas Gleixner
parent c5eb0a6123
commit 280abe14b6

View File

@ -902,6 +902,8 @@ static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end
static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
{
const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
vmemmap_flush_unused_pmd();
/*
@ -914,8 +916,7 @@ static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long
* Mark with PAGE_UNUSED the unused parts of the new memmap range
*/
if (!IS_ALIGNED(start, PMD_SIZE))
memset((void *)start, PAGE_UNUSED,
start - ALIGN_DOWN(start, PMD_SIZE));
memset((void *)page, PAGE_UNUSED, start - page);
/*
* We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of