[PATCH] platform/mellanox: mlxreg-hotplug: Remove redundant NULL-check

Daniil Dulov posted 1 patch 1 year, 9 months ago
drivers/platform/mellanox/mlxreg-hotplug.c | 14 --------------
1 file changed, 14 deletions(-)
[PATCH] platform/mellanox: mlxreg-hotplug: Remove redundant NULL-check
Posted by Daniil Dulov 1 year, 9 months ago
Pointer item is checked fo NULL at mlxreg_hotplug_work_helper() and then
it is dereferenced to produce dev_err().
This pointer is also dereferenced before calling this function and should
never be NULL except some piece of hardware is broken as it is said in
the comment before the check. So, this check can be safely removed.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: c6acad68eb2d ("platform/mellanox: mlxreg-hotplug: Modify to use a regmap interface")
Signed-off-by: Daniil Dulov <d.dulov@aladdin.ru>
---
 drivers/platform/mellanox/mlxreg-hotplug.c | 14 --------------
 1 file changed, 14 deletions(-)

diff --git a/drivers/platform/mellanox/mlxreg-hotplug.c b/drivers/platform/mellanox/mlxreg-hotplug.c
index 5c022b258f91..0ce9fff1f7d4 100644
--- a/drivers/platform/mellanox/mlxreg-hotplug.c
+++ b/drivers/platform/mellanox/mlxreg-hotplug.c
@@ -348,20 +348,6 @@ mlxreg_hotplug_work_helper(struct mlxreg_hotplug_priv_data *priv,
 	u32 regval, bit;
 	int ret;
 
-	/*
-	 * Validate if item related to received signal type is valid.
-	 * It should never happen, excepted the situation when some
-	 * piece of hardware is broken. In such situation just produce
-	 * error message and return. Caller must continue to handle the
-	 * signals from other devices if any.
-	 */
-	if (unlikely(!item)) {
-		dev_err(priv->dev, "False signal: at offset:mask 0x%02x:0x%02x.\n",
-			item->reg, item->mask);
-
-		return;
-	}
-
 	/* Mask event. */
 	ret = regmap_write(priv->regmap, item->reg + MLXREG_HOTPLUG_MASK_OFF,
 			   0);
-- 
2.25.1
Re: [PATCH] platform/mellanox: mlxreg-hotplug: Remove redundant NULL-check
Posted by Ilpo Järvinen 1 year, 9 months ago
On Wed, 06 Mar 2024 18:38:04 +0300, Daniil Dulov wrote:

> Pointer item is checked fo NULL at mlxreg_hotplug_work_helper() and then
> it is dereferenced to produce dev_err().
> This pointer is also dereferenced before calling this function and should
> never be NULL except some piece of hardware is broken as it is said in
> the comment before the check. So, this check can be safely removed.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> [...]


Thank you for your contribution, it has been applied to my local
review-ilpo branch. Note it will show up in the public
platform-drivers-x86/review-ilpo branch only once I've pushed my
local branch there, which might take a while.

The list of commits applied:
[1/1] platform/mellanox: mlxreg-hotplug: Remove redundant NULL-check
      commit: 576b82c3c9bf021af4984aafc105508c99660667

--
 i.