Re: [PATCH 6.12.y 4/4] crypto: x86/aegis - Fix sleeping when disallowed on PREEMPT_RT

[Eric Biggers <ebiggers@kernel.org>]

On Thu, Aug 21, 2025 at 11:06:17PM -0400, Sasha Levin wrote:
> From: Eric Biggers <ebiggers@kernel.org>
> 
> [ Upstream commit c7f49dadfcdf27e1f747442e874e9baa52ab7674 ]
> 
> skcipher_walk_done() can call kfree(), which takes a spinlock, which
> makes it incorrect to call while preemption is disabled on PREEMPT_RT.
> Therefore, end the kernel-mode FPU section before calling
> skcipher_walk_done(), and restart it afterwards.
> 
> Moreover, pass atomic=false to skcipher_walk_aead_encrypt() instead of
> atomic=true.  The point of atomic=true was to make skcipher_walk_done()
> safe to call while in a kernel-mode FPU section, but that does not
> actually work.  So just use the usual atomic=false.
> 
> Fixes: 1d373d4e8e15 ("crypto: x86 - Add optimized AEGIS implementations")
> Cc: stable@vger.kernel.org
> Signed-off-by: Eric Biggers <ebiggers@kernel.org>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  arch/x86/crypto/aegis128-aesni-glue.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)

1. Missing Cc of the relevant mailing lists
2. Missing cover letter
3. Missing base-commit, and doesn't apply to stable/linux-6.16.y
4. Two different series were sent out, both containing this patch

No reason to even take a look at the patch content until it's in a
reviewable state.

- Eric