Re: [Xen-devel] arm: Missing memset in setup_frametable_mappings

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 10.03.16 at 01:08, <vikrams@xxxxxxxxxxxxxx> wrote:
> I believe there is a bug in setup_frametable_mappings() where the function
> allocates pages for pagetables via alloc_boot_pages() but does not zero them
> out. This results in a crash on Qualcomm systems when prefetching is enabled
> since the processor is free to prefetch a location for which it finds a
> 'valid'
> translation in the page tables, but actually holds uninitialized memory.
> 
> A memset to 0 of the variable 'second' for the nr_second pages that were
> allocated fixes the problem.
> 
> I didn't see a fix in master branch but may have missed a bug report on the
> mailing list.

Why don't you submit your patch then? That said, I'm getting the
impression that all three uses of alloc_boot_pages() in arm/mm.c
have this problem, not just the one you mention.

Jan


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