netdev - Re: [PATCH net-next 2/6] tsnep: Add XDP TX support

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:   Wed, 07 Dec 2022 11:24:21 +0100
From:   Paolo Abeni <pabeni@...hat.com>
To:     Gerhard Engleder <gerhard@...leder-embedded.com>,
        netdev@...r.kernel.org, bpf@...r.kernel.org
Cc:     davem@...emloft.net, kuba@...nel.org, edumazet@...gle.com,
        ast@...nel.org, daniel@...earbox.net, hawk@...nel.org,
        john.fastabend@...il.com
Subject: Re: [PATCH net-next 2/6] tsnep: Add XDP TX support

On Sat, 2022-12-03 at 22:54 +0100, Gerhard Engleder wrote:
[...]
> +/* This function requires __netif_tx_lock is held by the caller. */
> +static int tsnep_xdp_xmit_frame_ring(struct xdp_frame *xdpf,
> +				     struct tsnep_tx *tx, bool dma_map)
> +{
> +	struct skb_shared_info *shinfo = xdp_get_shared_info_from_frame(xdpf);
> +	unsigned long flags;
> +	int count = 1;
> +	struct tsnep_tx_entry *entry;
> +	int length;
> +	int i;
> +	int retval;
> +
> +	if (unlikely(xdp_frame_has_frags(xdpf)))
> +		count += shinfo->nr_frags;
> +
> +	spin_lock_irqsave(&tx->lock, flags);

Not strictily related to this patch, but why are you using the _irqsafe
variant? it looks like all the locak users are either in process or BH
context.

Thanks!

Paolo