linux/arch/x86/mm
Oscar Salvador 8d400913c2 x86/vmemmap: handle unpopulated sub-pmd ranges
When sizeof(struct page) is not a power of 2, sections do not span a PMD
anymore and so when populating them some parts of the PMD will remain
unused.

Because of this, PMDs will be left behind when depopulating sections since
remove_pmd_table() thinks that those unused parts are still in use.

Fix this by marking the unused parts with PAGE_UNUSED, so memchr_inv()
will do the right thing and will let us free the PMD when the last user of
it is gone.

This patch is based on a similar patch by David Hildenbrand:

https://lore.kernel.org/linux-mm/20200722094558.9828-9-david@redhat.com/

[osalvador@suse.de: go back to the ifdef version]
  Link: https://lkml.kernel.org/r/YGy++mSft7K4u+88@localhost.localdomain

Link: https://lkml.kernel.org/r/20210309214050.4674-4-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:38 -07:00
..
pat x86/pat: Do not compile stubbed functions when X86_PAT is off 2021-04-14 08:21:41 +02:00
amdtopology.c
cpu_entry_area.c x86/dumpstack/64: Add noinstr version of get_stack_info() 2020-09-09 11:33:19 +02:00
debug_pagetables.c mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
dump_pagetables.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
extable.c This feature enhances the current guest memory encryption support 2020-10-14 10:21:34 -07:00
fault.c x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
highmem_32.c x86/mm/highmem: Use generic kmap atomic implementation 2020-11-06 23:14:55 +01:00
hugetlbpage.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
ident_map.c x86/mm/ident_map: Check for errors from ident_pud_init() 2020-10-28 14:48:30 +01:00
init_32.c x86/mm/highmem: Use generic kmap atomic implementation 2020-11-06 23:14:55 +01:00
init_64.c x86/vmemmap: handle unpopulated sub-pmd ranges 2021-04-30 11:20:38 -07:00
init.c The x86 MM changes in this cycle were: 2021-04-29 11:41:43 -07:00
iomap_32.c io-mapping: Cleanup atomic iomap 2020-11-06 23:14:58 +01:00
ioremap.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
kasan_init_64.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
kaslr.c x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
kmmio.c x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
maccess.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
Makefile kbuild: remove cc-option test of -fno-stack-protector 2020-07-07 11:13:10 +09:00
mem_encrypt_boot.S x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
mem_encrypt_identity.c x86/sev: Do not require Hypervisor CPUID bit for SEV guests 2021-03-18 16:44:40 +01:00
mem_encrypt.c Add support for SEV-ES guests booting through the 32-bit boot path, along with 2021-04-26 09:11:10 -07:00
mm_internal.h x86/mm: thread pgprot_t through init_memory_mapping() 2020-04-10 15:36:21 -07:00
mmap.c x86/mm/mmap: Fix -Wmissing-prototypes warnings 2020-04-22 20:19:48 +02:00
mmio-mod.c x86: Remove definition of DEBUG 2021-01-15 08:23:10 +01:00
numa_32.c x86/mm: Drop deprecated DISCONTIGMEM support for 32-bit 2020-05-28 18:34:30 +02:00
numa_64.c
numa_emulation.c x86/numa: cleanup configuration dependent command-line options 2020-10-13 18:38:27 -07:00
numa_internal.h
numa.c mm: fix phys_to_target_node() and memory_add_physaddr_to_nid() exports 2020-11-22 10:48:22 -08:00
pf_in.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
pf_in.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
pgtable_32.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
pgtable.c x86/mm: Fix leak of pmd ptlock 2021-01-05 11:40:23 +01:00
physaddr.c mm, x86/mm: Untangle address space layout definitions from basic pgtable type definitions 2019-12-10 10:12:55 +01:00
physaddr.h
pkeys.c x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
pti.c x86/process/64: Move cpu_current_top_of_stack out of TSS 2021-03-28 22:40:10 +02:00
setup_nx.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
srat.c
testmmiotrace.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
tlb.c The x86 MM changes in this cycle were: 2021-04-29 11:41:43 -07:00