Re: [PATCH] crypto: ccree - reduce kernel stack usage with clang

From: Gilad Ben-Yossef
Date: Sun Mar 17 2019 - 02:07:02 EST

On Thu, Mar 14, 2019 at 11:10 AM Arnd Bergmann <arnd@xxxxxxxx> wrote:
> Building with clang for a 32-bit architecture runs over the stack
> frame limit in the setkey function:
> drivers/crypto/ccree/cc_cipher.c:318:12: error: stack frame size of 1152 bytes in function 'cc_cipher_setkey' [-Werror,-Wframe-larger-than=]
> The problem is that there are two large variables: the temporary
> 'tmp' array and the SHASH_DESC_ON_STACK() declaration. Moving
> the first into the block in which it is used reduces the
> total frame size to 768 bytes, which seems more reasonable
> and is under the warning limit.

Thank you , Ard.

I will also revisit splitting that function to further reduce stack
usage after I finish tackling the fallout of the new testmgr... :-)

Acked-By: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx>

Gilad Ben-Yossef
Chief Coffee Drinker

values of Î will give rise to dom!