lkml.org 
[lkml]   [2015]   [Sep]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] powerpc: define empty enable_kernel_vsx() when CONFIG_VSX=n
From
Date
On 09/08/2015 08:13 PM, Michael Ellerman wrote:
> On Tue, 2015-09-08 at 17:19 -0600, Tim Gardner wrote:
>> On 09/08/2015 04:47 PM, Paul Mackerras wrote:
>>> On Tue, Sep 08, 2015 at 12:13:11PM -0600, tim.gardner@canonical.com wrote:
>>>> From: Tim Gardner <tim.gardner@canonical.com>
>>>>
>>>> commit 72cd7b44bc99 ("powerpc: Uncomment and make enable_kernel_vsx()
>>>> routine available") neglected to define an empty inline replacement for
>>>> enable_kernel_vsx() when CONFIG_VSX=n.
>>>
>>> If code that wants to call enable_kernel_vsx() is getting compiled in
>>> when CONFIG_VSX=n, that's a worry. Is this patch motivated by an
>>> actual compile failure? If so what was the failure?
>>
>> I was having link failures after backporting 'crypto: nx' patches to a
>> 4.2 based kernel. You may have a point in that the upstream Kconfig will
>> not allow those files to be compiled if CONFIG_VSX=n. I will check in my
>> morning if to see if I can reproduce the same link error in mainline.
>
> I suspect the problem is the "vmx" crypto actually.
>
> $ git grep enable_kernel_vsx drivers/
> drivers/crypto/vmx/aes.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes_cbc.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes_cbc.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes_cbc.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes_ctr.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes_ctr.c: enable_kernel_vsx();
> drivers/crypto/vmx/aes_ctr.c: enable_kernel_vsx();
> drivers/crypto/vmx/ghash.c: enable_kernel_vsx();
> drivers/crypto/vmx/ghash.c: enable_kernel_vsx();
> drivers/crypto/vmx/ghash.c: enable_kernel_vsx();
> drivers/crypto/vmx/ghash.c: enable_kernel_vsx();
>
>
> That appears to all be controlled by CONFIG_CRYPTO_DEV_VMX_ENCRYPT, which
> depends on CONFIG_CRYPTO_DEV_VMX, which depends on PPC64.
>
> So that looks like it will break terribly if VSX is turned off.
>
> We do have an automated test build with VSX turned off, but it doesn't have
> CONFIG_CRYPTO_DEV_VMX enabled :/
>
>
> Having said all that, why are you building a ppc64 kernel with VSX turned off?
>
> cheers
>
>

I'm pretty sure my problem is that I'm building a 32bit powerpc with
CONFIG_CRYPTO_DEV_VMX_ENCRYPT=y, though it is hard to tell for sure with
the interleaved build output from 4 parallel builds (powerpc-smp
powerpc64-smp powerpc-e500mc powerpc64-emb). Your proposed patch
("[PATCH v2] crypto: vmx - VMX crypto should depend on CONFIG_VSX")
fixes my problems (and makes more sense then my patch), so I suddenly
don't care as much.

rtg
--
Tim Gardner tim.gardner@canonical.com


\
 
 \ /
  Last update: 2015-09-09 15:41    [W:0.069 / U:2.096 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site