Re: [PATCH v2 1/3] readq/writeq: Add explicit lo_hi_[read|write]_q and hi_lo_[read|write]_q
From: Borislav Petkov
Date: Fri Jul 04 2014 - 10:08:13 EST
On Thu, Jun 26, 2014 at 09:58:28PM +0000, Jason Baron wrote:
> Even on x86-64, I've found the need to break up a readq() into 2 readl()
> calls. According to the Intel datasheet for the E3-1200 processor:
>
> "
> Software must not access B0/D0/F0 32-bit memory-mapped registers with
> requests that cross a DW boundary.
> "
>
> (http://www.intel.com/content/www/us/en/processors/xeon/xeon-e3-1200-family-vol-2-datasheet.html p. 16)
>
> I can confirm this is true via several hard machine lockups.
>
> Thus, add explicit hi_lo_[readq|write]_q and lo_hi_[read|write]_q so that these
> uses are spelled out.
>
> Signed-off-by: Jason Baron <jbaron@xxxxxxxxxx>
Applied, thanks.
--
Regards/Gruss,
Boris.
Sent from a fat crate under my desk. Formatting is fine.
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