[PATCH] crypto: serpent - mark __serpent_setkey_sbox noinline

From: Arnd Bergmann <arnd@arndb.de>
To: Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>, Eric Biggers <ebiggers@google.com>,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] crypto: serpent - mark __serpent_setkey_sbox noinline
Date: Mon, 17 Jun 2019 13:59:08 +0200	[thread overview]
Message-ID: <20190617115927.3813471-1-arnd@arndb.de> (raw)

The same bug that gcc hit in the past is apparently now showing
up with clang, which decides to inline __serpent_setkey_sbox:

crypto/serpent_generic.c:268:5: error: stack frame size of 2112 bytes in function '__serpent_setkey' [-Werror,-Wframe-larger-than=]

Marking it 'noinline' reduces the stack usage from 2112 bytes to
192 and 96 bytes, respectively, and seems to generate more
useful object code.

Fixes: c871c10e4ea7 ("crypto: serpent - improve __serpent_setkey with UBSAN")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 crypto/serpent_generic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/serpent_generic.c b/crypto/serpent_generic.c
index e57757904677..183661faf420 100644
--- a/crypto/serpent_generic.c
+++ b/crypto/serpent_generic.c
@@ -225,7 +225,7 @@
 	x4 ^= x2;					\
 	})
 
-static void __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2, u32 r3, u32 r4, u32 *k)
+static void noinline __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2, u32 r3, u32 r4, u32 *k)
 {
 	k += 100;
 	S3(r3, r4, r0, r1, r2); store_and_load_keys(r1, r2, r4, r3, 28, 24);
-- 
2.20.0

