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SubjectRe: [PATCH v2] [v2] crypto: aes-generic - fix aes-generic regression on powerpc
On Mon, Jan 15, 2018 at 05:07:22PM +0100, Arnd Bergmann wrote:
> My last bugfix added -Os on the command line, which unfortunately caused
> a build regression on powerpc in some configurations.
> I've done some more analysis of the original problem and found slightly
> different workaround that avoids this regression and also results in
> better performance on gcc-7.0: -fcode-hoisting is an optimization step
> that got added in gcc-7 and that for all gcc-7 versions causes worse
> performance.
> This disables -fcode-hoisting on all compilers that understand the option.
> For gcc-7.1 and 7.2 I found the same performance as my previous patch
> (using -Os), in gcc-7.0 it was even better. On gcc-8 I could see no
> change in performance from this patch. In theory, code hoisting should
> not be able make things better for the AES cipher, so leaving it
> disabled for gcc-8 only serves to simplify the Makefile change.
> Reported-by: kbuild test robot <>
> Link:
> Link:
> Link:
> Fixes: 148b974deea9 ("crypto: aes-generic - build with -Os on gcc-7+")
> Signed-off-by: Arnd Bergmann <>

Patch applied. Thanks.
Email: Herbert Xu <>
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