[PATCH v2] powerpc/crypto/crct10dif-vpmsum: Fix missing preempt_disable()

[Herbert Xu]

On Thu, Apr 20, 2017 at 03:35:09PM +1000, Michael Ellerman wrote:
> In crct10dif_vpmsum() we call enable_kernel_altivec() without first
> disabling preemption, which is not allowed.
> 
> It used to be sufficient just to call pagefault_disable(), because that
> also disabled preemption. But the two were decoupled in commit 8222dbe21e79
> ("sched/preempt, mm/fault: Decouple preemption from the page fault
> logic") in mid 2015.
> 
> The crct10dif-vpmsum code inherited this bug from the crc32c-vpmsum code
> on which it was modelled.
> 
> So add the missing preempt_disable/enable(). We should also call
> disable_kernel_fp(), although it does nothing by default, there is a
> debug switch to make it active and all enables should be paired with
> disables.
> 
> Fixes: b01df1c16c9a ("crypto: powerpc - Add CRC-T10DIF acceleration")
> Acked-by: Daniel Axtens <dja at axtens.net>
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
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