[PATCH V2 1/2] efi/unaccepted: Do not let /proc/vmcore try to access unaccepted memory
David Hildenbrand
david at redhat.com
Tue Sep 12 00:18:30 PDT 2023
On 11.09.23 13:21, Adrian Hunter wrote:
> 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.
>
> Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
> ---
[...]
> +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 */
As stated, if the relevant table is not already properly populated with
information about unaccepted memory by the first kernel, this probably
logically belongs into Kirills series.
Reviewed-by: David Hildenbrand <david at redhat.com>
--
Cheers,
David / dhildenb
More information about the kexec
mailing list