diff options
| author | Adrian Hunter <adrian.hunter@intel.com> | 2023-09-11 14:21:13 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-04 10:32:22 -0700 |
| commit | 7cd34dd3c9bf1d67ce7d1ab3fe8886c583ae0d9a (patch) | |
| tree | a76caf2a4376cdc6598e2a4952c92f741e784ccb /include/linux/mm.h | |
| parent | 46fa84a2b920f91780db3347de81d65efb668301 (diff) | |
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
dcdfdd40fa82 ("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
dcdfdd40fa82 ("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>
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 21c3d4e8a282..31dc25d3f6b5 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -4054,4 +4054,11 @@ static inline void accept_memory(phys_addr_t start, phys_addr_t end) #endif +static inline bool pfn_is_unaccepted_memory(unsigned long pfn) +{ + phys_addr_t paddr = pfn << PAGE_SHIFT; + + return range_contains_unaccepted_memory(paddr, paddr + PAGE_SIZE); +} + #endif /* _LINUX_MM_H */ |