Re: [PATCH net-next v3 09/13] net: mana: keep per-queue statistics in the port context

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] False-positive ASSERT_RTNL() warning during probe failure.
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commit b6c8581e036e2f21afeed4eb0d2e9961d1a0d2f5
Author: Long Li <longli@microsoft.com>
Subject: net: mana: keep per-queue statistics in the port context

This patch moves rx and tx statistics from the individual queue structures
into port-context arrays. This ensures that the interface counters are not
lost across reconfigurations such as ethtool channel count or MTU changes.

> diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
> --- a/drivers/net/ethernet/microsoft/mana/mana_en.c
> +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
[ ... ]
> +static void mana_fold_rxq_stats(struct mana_port_context *apc,
> +				struct mana_rxq *rxq)
> +{
> +	struct mana_stats_rx *src = &rxq->drain_stats;
> +	struct mana_stats_rx *dst;
> +	unsigned int i;
> +
> +	ASSERT_RTNL();
[ ... ]
> @@ -3017,6 +3163,11 @@ static void mana_destroy_rxq(struct mana_port_context *apc,
>  		netif_napi_del_locked(napi);
>  	}
>  
> +	/* No poller left, so this is the last chance to keep what the queue
> +	 * counted after it stopped being the live one.
> +	 */
> +	mana_fold_rxq_stats(apc, rxq);
> +

[Severity: Medium]
Will this trigger a false-positive ASSERT_RTNL() warning if the driver
fails to probe?

If mana_init_port() fails during device probe (e.g., due to a memory
allocation failure or hardware timeout), the error recovery path calls
mana_destroy_rxqs() and then mana_destroy_rxq(), which now unconditionally
calls mana_fold_rxq_stats().

Since the probe path in mana_probe_port() invokes mana_init_port()
before calling register_netdev(), the RTNL lock is not held yet. This
seems like it would trigger the new ASSERT_RTNL() inside
mana_fold_rxq_stats() during a valid error recovery path.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260901014442.2945689-1-longli@microsoft.com?part=9