| Message ID | 20190314090951.840339-1-arnd@arndb.de (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | crypto: ccree - reduce kernel stack usage with clang | expand |
On Thu, Mar 14, 2019 at 11:10 AM Arnd Bergmann <arnd@arndb.de> wrote: > > Building with clang for a 32-bit architecture runs over the stack > frame limit in the setkey function: > > drivers/crypto/ccree/cc_cipher.c:318:12: error: stack frame size of 1152 bytes in function 'cc_cipher_setkey' [-Werror,-Wframe-larger-than=] > > The problem is that there are two large variables: the temporary > 'tmp' array and the SHASH_DESC_ON_STACK() declaration. Moving > the first into the block in which it is used reduces the > total frame size to 768 bytes, which seems more reasonable > and is under the warning limit. > Thank you , Ard. I will also revisit splitting that function to further reduce stack usage after I finish tackling the fallout of the new testmgr... :-) Acked-By: Gilad Ben-Yossef <gilad@benyossef.com> Gilad
On Thu, Mar 14, 2019 at 10:09:44AM +0100, Arnd Bergmann wrote: > Building with clang for a 32-bit architecture runs over the stack > frame limit in the setkey function: > > drivers/crypto/ccree/cc_cipher.c:318:12: error: stack frame size of 1152 bytes in function 'cc_cipher_setkey' [-Werror,-Wframe-larger-than=] > > The problem is that there are two large variables: the temporary > 'tmp' array and the SHASH_DESC_ON_STACK() declaration. Moving > the first into the block in which it is used reduces the > total frame size to 768 bytes, which seems more reasonable > and is under the warning limit. > > Fixes: 63ee04c8b491 ("crypto: ccree - add skcipher support") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > drivers/crypto/ccree/cc_cipher.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Patch applied. Thanks.
diff --git a/drivers/crypto/ccree/cc_cipher.c b/drivers/crypto/ccree/cc_cipher.c index d9c17078517b..0abcdc224ab0 100644 --- a/drivers/crypto/ccree/cc_cipher.c +++ b/drivers/crypto/ccree/cc_cipher.c @@ -321,7 +321,6 @@ static int cc_cipher_setkey(struct crypto_skcipher *sktfm, const u8 *key, struct crypto_tfm *tfm = crypto_skcipher_tfm(sktfm); struct cc_cipher_ctx *ctx_p = crypto_tfm_ctx(tfm); struct device *dev = drvdata_to_dev(ctx_p->drvdata); - u32 tmp[DES3_EDE_EXPKEY_WORDS]; struct cc_crypto_alg *cc_alg = container_of(tfm->__crt_alg, struct cc_crypto_alg, skcipher_alg.base); @@ -347,6 +346,7 @@ static int cc_cipher_setkey(struct crypto_skcipher *sktfm, const u8 *key, * HW does the expansion on its own. */ if (ctx_p->flow_mode == S_DIN_to_DES) { + u32 tmp[DES3_EDE_EXPKEY_WORDS]; if (keylen == DES3_EDE_KEY_SIZE && __des3_ede_setkey(tmp, &tfm->crt_flags, key, DES3_EDE_KEY_SIZE)) {
Building with clang for a 32-bit architecture runs over the stack frame limit in the setkey function: drivers/crypto/ccree/cc_cipher.c:318:12: error: stack frame size of 1152 bytes in function 'cc_cipher_setkey' [-Werror,-Wframe-larger-than=] The problem is that there are two large variables: the temporary 'tmp' array and the SHASH_DESC_ON_STACK() declaration. Moving the first into the block in which it is used reduces the total frame size to 768 bytes, which seems more reasonable and is under the warning limit. Fixes: 63ee04c8b491 ("crypto: ccree - add skcipher support") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/crypto/ccree/cc_cipher.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)