Re: [PATCH v2 2/2] smartpqi: limit transfer length to 1MB

From: Johannes Thumshirn
Date: Fri Jun 23 2017 - 09:02:06 EST


On Fri, Jun 23, 2017 at 05:40:06PM +0800, Yadan Fan wrote:
> The smartpqi firmware will bypass the cache for any request larger
> than 1MB, so we should cap the request size to avoid any
> performance degradation in kernels later than v4.3
>
> This degradation is caused from d2be537c3ba3568acd79cd178327b842e60d035e,
> which changed max_sectors_kb to 1280k, but the hardware is able to
> work fine with it, so the true fix should be from smartpqi driver.
>
> Signed-off-by: Yadan Fan <ydfan@xxxxxxxx>
> ---

Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
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