Re: [PATCH net] bnxt_en: Fix the resource check condition for RSS contexts

[Simon Horman <horms@kernel.org>]

On Wed, Jul 03, 2024 at 11:01:12AM -0700, Michael Chan wrote:
> From: Pavan Chebbi <pavan.chebbi@broadcom.com>
> 
> While creating a new RSS context, bnxt_rfs_capable() currently
> makes a strict check to see if the required VNICs are already
> available.  If the current VNICs are not what is required,
> either too many or not enough, it will call the firmware to
> reserve the exact number required.
> 
> There is a bug in the firmware when the driver tries to
> relinquish some reserved VNICs and RSS contexts.  It will
> cause the default VNIC to lose its RSS configuration and
> cause receive packets to be placed incorrectly.
> 
> Workaround this problem by skipping the resource reduction.
> The driver will not reduce the VNIC and RSS context reservations
> when a context is deleted.  The resources will be available for
> use when new contexts are created later.
> 
> Potentially, this workaround can cause us to run out of VNIC
> and RSS contexts if there are a lot of VF functions creating
> and deleting RSS contexts.  In the future, we will conditionally
> disable this workaround when the firmware fix is available.
> 
> Fixes: 438ba39b25fe ("bnxt_en: Improve RSS context reservation infrastructure")
> Reported-by: Jakub Kicinski <kuba@kernel.org>
> Link: https://lore.kernel.org/netdev/20240625010210.2002310-1-kuba@kernel.org/
> Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
> Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
> Signed-off-by: Michael Chan <michael.chan@broadcom.com>

Reviewed-by: Simon Horman <horms@kernel.org>