netdev - Re: [PATCH] bgmac: driver for GBit MAC core on BCMA bus

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, 3 Jan 2013 21:30:27 +0100
From:	Francois Romieu <romieu@...zoreil.com>
To:	Rafał Miłecki <zajec5@...il.com>
Cc:	netdev@...r.kernel.org, "David S. Miller" <davem@...emloft.net>
Subject: Re: [PATCH] bgmac: driver for GBit MAC core on BCMA bus

Rafał Miłecki <zajec5@...il.com> :
[...]
> bgmac_chip_reset also does different things, so I can't just remove
> bgmac_chip_reset from bgmac_probe. I could add some parameter to
> bgmac_chip_reset to let it know if DMA should be reset as well, but
> I'm note sure about the advantage.

Forget it. I was completely wrong.

[...]
> > The driver should stop queueing after its processing if it detects that
> > it can't handle more requests.
> 
> I think it's what the code does... netif_stop_queue and return
> NETDEV_TX_BUSY. Anything wrong about it?

The driver does not hold its promise to send the packet. It should
netif_stop_queue and return NETDEV_TX_OK after the last transmitted
packet.

[...]
> > Are we sure that the hardware will never read a descriptor where ctl0 is
> > set and ctl1 is not (start_xmit, dma starts, competing start_xmit, oops) ?
> 
> Do you mean more that one ->ndo_start_xmit(...) can be executed at a
> time ?

No. I was just wondering if a sequence of start_xmit could compete with
hardware DMA but I missed the BGMAC_DMA_TX_INDEX below. You may want a
mmiowb after the write to BGMAC_DMA_TX_INDEX though.

-- 
Ueimor
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html