diff mbox series

crypto: ccree - avoid out-of-range warnings from clang

Message ID 20210927121811.940899-1-arnd@kernel.org
State New
Headers show
Series crypto: ccree - avoid out-of-range warnings from clang | expand

Commit Message

Arnd Bergmann Sept. 27, 2021, 12:18 p.m. UTC
From: Arnd Bergmann <arnd@arndb.de>


clang points out inconsistencies in the FIELD_PREP() invocation in
this driver that result from the 'mask' being a 32-bit value:

drivers/crypto/ccree/cc_driver.c:117:18: error: result of comparison of constant 18446744073709551615 with expression of type 'u32' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare]
        cache_params |= FIELD_PREP(mask, val);
                        ^~~~~~~~~~~~~~~~~~~~~
include/linux/bitfield.h:94:3: note: expanded from macro 'FIELD_PREP'
                __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: ");    \
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/bitfield.h:52:28: note: expanded from macro '__BF_FIELD_CHECK'
                BUILD_BUG_ON_MSG((_mask) > (typeof(_reg))~0ull,         \
                ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This does not happen in other places that just pass a constant here.

Work around the warnings by widening the type of the temporary variable.

Fixes: 05c2a705917b ("crypto: ccree - rework cache parameters handling")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

---
 drivers/crypto/ccree/cc_driver.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

-- 
2.29.2

Comments

Gilad Ben-Yossef Sept. 28, 2021, 2:02 p.m. UTC | #1
Hi,

Thank you Arnd.

On Mon, Sep 27, 2021 at 3:18 PM Arnd Bergmann <arnd@kernel.org> wrote:
>

> From: Arnd Bergmann <arnd@arndb.de>

>

> clang points out inconsistencies in the FIELD_PREP() invocation in

> this driver that result from the 'mask' being a 32-bit value:

>

> drivers/crypto/ccree/cc_driver.c:117:18: error: result of comparison of constant 18446744073709551615 with expression of type 'u32' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare]

>         cache_params |= FIELD_PREP(mask, val);

>                         ^~~~~~~~~~~~~~~~~~~~~

> include/linux/bitfield.h:94:3: note: expanded from macro 'FIELD_PREP'

>                 __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: ");    \

>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> include/linux/bitfield.h:52:28: note: expanded from macro '__BF_FIELD_CHECK'

>                 BUILD_BUG_ON_MSG((_mask) > (typeof(_reg))~0ull,         \

>                 ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

>

> This does not happen in other places that just pass a constant here.

>

> Work around the warnings by widening the type of the temporary variable.

>

> Fixes: 05c2a705917b ("crypto: ccree - rework cache parameters handling")

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


Acked-by: Gilad ben-Yossef <gilad@benyossef.com>


Gilad



-- 
Gilad Ben-Yossef
Chief Coffee Drinker

values of β will give rise to dom!
Herbert Xu Oct. 8, 2021, 12:23 p.m. UTC | #2
On Mon, Sep 27, 2021 at 02:18:03PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>

> 

> clang points out inconsistencies in the FIELD_PREP() invocation in

> this driver that result from the 'mask' being a 32-bit value:

> 

> drivers/crypto/ccree/cc_driver.c:117:18: error: result of comparison of constant 18446744073709551615 with expression of type 'u32' (aka 'unsigned int') is always false [-Werror,-Wtautological-constant-out-of-range-compare]

>         cache_params |= FIELD_PREP(mask, val);

>                         ^~~~~~~~~~~~~~~~~~~~~

> include/linux/bitfield.h:94:3: note: expanded from macro 'FIELD_PREP'

>                 __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: ");    \

>                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> include/linux/bitfield.h:52:28: note: expanded from macro '__BF_FIELD_CHECK'

>                 BUILD_BUG_ON_MSG((_mask) > (typeof(_reg))~0ull,         \

>                 ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> 

> This does not happen in other places that just pass a constant here.

> 

> Work around the warnings by widening the type of the temporary variable.

> 

> Fixes: 05c2a705917b ("crypto: ccree - rework cache parameters handling")

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

> ---

>  drivers/crypto/ccree/cc_driver.c | 3 ++-

>  1 file changed, 2 insertions(+), 1 deletion(-)


Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
diff mbox series

Patch

diff --git a/drivers/crypto/ccree/cc_driver.c b/drivers/crypto/ccree/cc_driver.c
index e599ac6dc162..790fa9058a36 100644
--- a/drivers/crypto/ccree/cc_driver.c
+++ b/drivers/crypto/ccree/cc_driver.c
@@ -103,7 +103,8 @@  MODULE_DEVICE_TABLE(of, arm_ccree_dev_of_match);
 static void init_cc_cache_params(struct cc_drvdata *drvdata)
 {
 	struct device *dev = drvdata_to_dev(drvdata);
-	u32 cache_params, ace_const, val, mask;
+	u32 cache_params, ace_const, val;
+	u64 mask;
 
 	/* compute CC_AXIM_CACHE_PARAMS */
 	cache_params = cc_ioread(drvdata, CC_REG(AXIM_CACHE_PARAMS));