[net,v1] devlink: Don't throw an error if flash notification sent before devlink visible

Commit Message

Leon Romanovsky Nov. 17, 2021, 2:49 p.m. UTC

From: Leon Romanovsky <[e-mail]>

The mlxsw driver calls to various devlink flash routines even before
users can get any access to the devlink instance itself. For example,
mlxsw_core_fw_rev_validate() one of such functions.

__mlxsw_core_bus_device_register
 -> mlxsw_core_fw_rev_validate
  -> mlxsw_core_fw_flash
   -> mlxfw_firmware_flash
    -> mlxfw_status_notify
     -> devlink_flash_update_status_notify
      -> __devlink_flash_update_notify
       -> WARN_ON(...)

It causes to the WARN_ON to trigger warning about devlink not registered.

Fixes: cf530217408e ("devlink: Notify users when objects are accessible")
Reported-by: Danielle Ratson <[e-mail]>
Tested-by: Danielle Ratson <[e-mail]>
Signed-off-by: Leon Romanovsky <[e-mail]>
---
v1:
 * Used Jakub's suggestion to silently drop flash notifications if
   devlink is not visible yet.
 * Used right person for Reported and Tested tags. 
v0: https://lore.kernel.org/all/[e-mail]
---
 net/core/devlink.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Jakub Kicinski Nov. 18, 2021, 4:29 a.m. UTC | #1

On Wed, 17 Nov 2021 16:49:09 +0200 Leon Romanovsky wrote:
> From: Leon Romanovsky <[e-mail]>
> 
> The mlxsw driver calls to various devlink flash routines even before
> users can get any access to the devlink instance itself. For example,
> mlxsw_core_fw_rev_validate() one of such functions.
> 
> __mlxsw_core_bus_device_register
>  -> mlxsw_core_fw_rev_validate
>   -> mlxsw_core_fw_flash
>    -> mlxfw_firmware_flash
>     -> mlxfw_status_notify
>      -> devlink_flash_update_status_notify
>       -> __devlink_flash_update_notify
>        -> WARN_ON(...)  
> 
> It causes to the WARN_ON to trigger warning about devlink not registered.
> 
> Fixes: cf530217408e ("devlink: Notify users when objects are accessible")
> Reported-by: Danielle Ratson <[e-mail]>
> Tested-by: Danielle Ratson <[e-mail]>
> Signed-off-by: Leon Romanovsky <[e-mail]>

Acked-by: Jakub Kicinski <[e-mail]>

[e-mail] Nov. 18, 2021, 11:40 a.m. UTC | #2

Hello:

This patch was applied to netdev/net.git (master)
by David S. Miller <[e-mail]>:

On Wed, 17 Nov 2021 16:49:09 +0200 you wrote:
> From: Leon Romanovsky <[e-mail]>
> 
> The mlxsw driver calls to various devlink flash routines even before
> users can get any access to the devlink instance itself. For example,
> mlxsw_core_fw_rev_validate() one of such functions.
> 
> __mlxsw_core_bus_device_register
>  -> mlxsw_core_fw_rev_validate
>   -> mlxsw_core_fw_flash
>    -> mlxfw_firmware_flash
>     -> mlxfw_status_notify
>      -> devlink_flash_update_status_notify
>       -> __devlink_flash_update_notify
>        -> WARN_ON(...)
> 
> [...]

Here is the summary with links:
  - [net,v1] devlink: Don't throw an error if flash notification sent before devlink visible
    https://git.kernel.org/netdev/net/c/fec1faf221f6

You are awesome, thank you!

Patch

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 5ba4f9434acd..5ad72dbfcd07 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -4229,7 +4229,9 @@  static void __devlink_flash_update_notify(struct devlink *devlink,
 	WARN_ON(cmd != DEVLINK_CMD_FLASH_UPDATE &&
 		cmd != DEVLINK_CMD_FLASH_UPDATE_END &&
 		cmd != DEVLINK_CMD_FLASH_UPDATE_STATUS);
-	WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));
+
+	if (!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED))
+		return;
 
 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (!msg)