[PATCH 1/7] crypto: octeon - don't disable bottom half in octeon-md5

From: Aaro Koskinen
Date: Sun Mar 08 2015 - 16:08:17 EST


Don't disable bottom half while the crypto engine is in use, as it
should be unnecessary: All kernel crypto engine usage is wrapped with
crypto engine state save/restore, so if we get interrupted by softirq
that uses crypto they should save and restore our context.

This actually fixes an issue when running OCTEON MD5 with interrupts
disabled (tcrypt mode=302). There's a WARNING because the module is
trying to enable the bottom half with irqs disabled:

[ 52.656610] ------------[ cut here ]------------
[ 52.661439] WARNING: CPU: 1 PID: 428 at /home/aaro/git/linux/kernel/softirq.c:150 __local_bh_enable_ip+0x9c/0xd8()
[ 52.671780] Modules linked in: tcrypt(+)
[...]
[ 52.763539] [<ffffffff8114082c>] warn_slowpath_common+0x94/0xd8
[ 52.769465] [<ffffffff81144614>] __local_bh_enable_ip+0x9c/0xd8
[ 52.775390] [<ffffffff81119574>] octeon_md5_final+0x12c/0x1e8
[ 52.781144] [<ffffffff81337050>] shash_compat_digest+0xd0/0x1b0

Signed-off-by: Aaro Koskinen <aaro.koskinen@xxxxxx>
---
arch/mips/cavium-octeon/crypto/octeon-md5.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/arch/mips/cavium-octeon/crypto/octeon-md5.c b/arch/mips/cavium-octeon/crypto/octeon-md5.c
index b909881..3dd8845 100644
--- a/arch/mips/cavium-octeon/crypto/octeon-md5.c
+++ b/arch/mips/cavium-octeon/crypto/octeon-md5.c
@@ -97,7 +97,6 @@ static int octeon_md5_update(struct shash_desc *desc, const u8 *data,
memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data,
avail);

- local_bh_disable();
preempt_disable();
flags = octeon_crypto_enable(&state);
octeon_md5_store_hash(mctx);
@@ -115,7 +114,6 @@ static int octeon_md5_update(struct shash_desc *desc, const u8 *data,
octeon_md5_read_hash(mctx);
octeon_crypto_disable(&state, flags);
preempt_enable();
- local_bh_enable();

memcpy(mctx->block, data, len);

@@ -133,7 +131,6 @@ static int octeon_md5_final(struct shash_desc *desc, u8 *out)

*p++ = 0x80;

- local_bh_disable();
preempt_disable();
flags = octeon_crypto_enable(&state);
octeon_md5_store_hash(mctx);
@@ -153,7 +150,6 @@ static int octeon_md5_final(struct shash_desc *desc, u8 *out)
octeon_md5_read_hash(mctx);
octeon_crypto_disable(&state, flags);
preempt_enable();
- local_bh_enable();

memcpy(out, mctx->hash, sizeof(mctx->hash));
memset(mctx, 0, sizeof(*mctx));
--
2.2.0

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