From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Unaligned writes on the kexec path
Date: Mon, 28 Nov 2011 14:24:39 +0000
Message-ID: <4ED399A7.1070108@citrix.com>
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To: Keir Fraser <keir.xen@gmail.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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Hello,

In c/s 7493bb48d89f, you change the internals of kexec_crash_save_info()
to reduce unaligned writes, but pass the resulting pointer back to
machine_crash_shutdown() which performs writes on the possibly unaligned
data structure.  There are also plenty of other writes on the kexec path
which are possibly or certainly unaligned.

What is the reason for wanting to reduce unaligned writes?

Would a better solution be to just ensure that the crash note itself is
properly aligned?

-- 
Andrew Cooper - Dom0 Kernel Engineer, Citrix XenServer
T: +44 (0)1223 225 900, http://www.citrix.com