Re: [PATCH v2] crypto: arm64/aes-blk - fix and move skcipher_walk_done out of kernel_neon_begin,_end

From: Will Deacon
Date: Fri Jun 08 2018 - 04:53:01 EST


On Fri, Jun 08, 2018 at 03:41:44PM +0800, Jia He wrote:
> In a arm64 server(QDF2400),I met a similar might-sleep warning as [1]:
> [ 7.019116] BUG: sleeping function called from invalid context at
> ./include/crypto/algapi.h:416
> [ 7.027863] in_atomic(): 1, irqs_disabled(): 0, pid: 410, name:
> cryptomgr_test
> [ 7.035106] 1 lock held by cryptomgr_test/410:
> [ 7.039549] #0: (ptrval) (&drbg->drbg_mutex){+.+.}, at:
> drbg_instantiate+0x34/0x398
> [ 7.048038] CPU: 9 PID: 410 Comm: cryptomgr_test Not tainted
> 4.17.0-rc6+ #27
> [ 7.068228] dump_backtrace+0x0/0x1c0
> [ 7.071890] show_stack+0x24/0x30
> [ 7.075208] dump_stack+0xb0/0xec
> [ 7.078523] ___might_sleep+0x160/0x238
> [ 7.082360] skcipher_walk_done+0x118/0x2c8
> [ 7.086545] ctr_encrypt+0x98/0x130
> [ 7.090035] simd_skcipher_encrypt+0x68/0xc0
> [ 7.094304] drbg_kcapi_sym_ctr+0xd4/0x1f8
> [ 7.098400] drbg_ctr_update+0x98/0x330
> [ 7.102236] drbg_seed+0x1b8/0x2f0
> [ 7.105637] drbg_instantiate+0x2ac/0x398
> [ 7.109646] drbg_kcapi_seed+0xbc/0x188
> [ 7.113482] crypto_rng_reset+0x4c/0xb0
> [ 7.117319] alg_test_drbg+0xec/0x330
> [ 7.120981] alg_test.part.6+0x1c8/0x3c8
> [ 7.124903] alg_test+0x58/0xa0
> [ 7.128044] cryptomgr_test+0x50/0x58
> [ 7.131708] kthread+0x134/0x138
> [ 7.134936] ret_from_fork+0x10/0x1c
>
> Seems there is a bug in Ard Biesheuvel's commit.
> Fixes: 683381747270 ("crypto: arm64/aes-blk - move kernel mode neon
> en/disable into loop")
>
> [1] https://www.spinics.net/lists/linux-crypto/msg33103.html
>
> Signed-off-by: jia.he@xxxxxxxxxxxxxxxx
> Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # 4.17
> ---
> v2: cc stable
> ---
> arch/arm64/crypto/aes-glue.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Acked-by: Will Deacon <will.deacon@xxxxxxx>

I'm assuming Herbert will pick this up as a fix.

Cheers,

Will