linux-kernel - Re: [PATCH net-next 3/3] net: stmmac: Introducing support for Page Pool

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 4 Jul 2019 11:39:16 +0200
From:   Jesper Dangaard Brouer <brouer@...hat.com>
To:     Jose Abreu <Jose.Abreu@...opsys.com>
Cc:     brouer@...hat.com, linux-kernel@...r.kernel.org,
        netdev@...r.kernel.org, linux-stm32@...md-mailman.stormreply.com,
        linux-arm-kernel@...ts.infradead.org,
        Joao Pinto <Joao.Pinto@...opsys.com>,
        "David S . Miller" <davem@...emloft.net>,
        Giuseppe Cavallaro <peppe.cavallaro@...com>,
        Alexandre Torgue <alexandre.torgue@...com>,
        Maxime Coquelin <mcoquelin.stm32@...il.com>,
        Maxime Ripard <maxime.ripard@...tlin.com>,
        Chen-Yu Tsai <wens@...e.org>
Subject: Re: [PATCH net-next 3/3] net: stmmac: Introducing support for Page
 Pool

On Wed,  3 Jul 2019 12:37:50 +0200
Jose Abreu <Jose.Abreu@...opsys.com> wrote:

> @@ -1498,8 +1479,9 @@ static void free_dma_rx_desc_resources(struct stmmac_priv *priv)
>  					  sizeof(struct dma_extended_desc),
>  					  rx_q->dma_erx, rx_q->dma_rx_phy);
>  
> -		kfree(rx_q->rx_skbuff_dma);
> -		kfree(rx_q->rx_skbuff);
> +		kfree(rx_q->buf_pool);
> +		if (rx_q->page_pool)
> +			page_pool_request_shutdown(rx_q->page_pool);
>  	}
>  }
>  

The page_pool_request_shutdown() API return indication if there are any
in-flight frames/pages, to know when it is safe to call
page_pool_free(), which you are also missing a call to.

This page_pool_request_shutdown() is only intended to be called from
xdp_rxq_info_unreg() code, that handles and schedule a work queue if it
need to wait for in-flight frames/pages.

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer