efi/unaccepted: do not let /proc/vmcore try to access unaccepted memory

Patch series "Do not try to access unaccepted memory", v2.

Support for unaccepted memory was added recently, refer commit
dcdfdd40 ("mm: Add support for unaccepted memory"), whereby
a virtual machine may need to accept memory before it can be used.

Plug a few gaps where RAM is exposed without checking if it is
unaccepted memory.


This patch (of 2):

Support for unaccepted memory was added recently, refer commit
dcdfdd40 ("mm: Add support for unaccepted memory"), whereby a virtual
machine may need to accept memory before it can be used.

Do not let /proc/vmcore try to access unaccepted memory because it can
cause the guest to fail.

For /proc/vmcore, which is read-only, this means a read or mmap of
unaccepted memory will return zeros.

Link: https://lkml.kernel.org/r/20230911112114.91323-1-adrian.hunter@intel.com
Link: https://lkml.kernel.org/r/20230911112114.91323-2-adrian.hunter@intel.com


Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>