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From: vikrams@codeaurora.org
To: xen-devel@lists.xenproject.org
Cc: stefano.stabellini@citrix.com, ian.campbell@citrix.com,
	shankerd@codeaurora.org
Subject: arm: Missing memset in setup_frametable_mappings
Date: Thu, 10 Mar 2016 00:08:00 -0000	[thread overview]
Message-ID: <136debf45304997fb7ff87bd0a1a10be.squirrel@codeaurora.org> (raw)

Hello Ian, Stefano,
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.

Thanks,
Vikram
Qualcomm Technologies Inc, on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux
Foundation Collaborative Project



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             reply	other threads:[~2016-03-10  0:08 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-10  0:08 vikrams [this message]
2016-03-10  8:51 ` arm: Missing memset in setup_frametable_mappings Jan Beulich

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