[PATCH RFC net-next 2/5] net: stmmac: remove redundant racy tear-down in stmmac_dvr_remove()

[Andrew Lunn]

On Thu, Feb 27, 2025 at 03:05:07PM +0000, Russell King (Oracle) wrote:
> While the network device is registered, it is published to userspace,
> and thus userspace can change its state. This means calling
> functions such as stmmac_stop_all_dma() and stmmac_mac_set() are
> racy.
> 
> Moreover, unregister_netdev() will unpublish the network device, and
> then if appropriate call the .ndo_stop() method, which is
> stmmac_release(). This will first call phylink_stop() which will
> synchronously take the link down, resulting in stmmac_mac_link_down()
> and stmmac_mac_set(, false) being called.
> 
> stmmac_release() will also call stmmac_stop_all_dma().
> 
> Consequently, neither of these two functions need to called prior
> to unregister_netdev() as that will safely call paths that will
> result in this work being done if necessary.
> 
> Remove these redundant racy calls.
> 
> Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>

Reviewed-by: Andrew Lunn <andrew at lunn.ch>

    Andrew