netdev - RE: [PATCH net-next v2 13/14] ravb: Update EMAC configuration mode comment

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:   Sun, 10 Oct 2021 10:56:32 +0000
From:   Biju Das <biju.das.jz@...renesas.com>
To:     Sergei Shtylyov <sergei.shtylyov@...il.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
CC:     Sergey Shtylyov <s.shtylyov@....ru>,
        Geert Uytterhoeven <geert+renesas@...der.be>,
        Sergey Shtylyov <s.shtylyov@...russia.ru>,
        Adam Ford <aford173@...il.com>, Andrew Lunn <andrew@...n.ch>,
        Yuusuke Ashizuka <ashiduka@...itsu.com>,
        Yoshihiro Shimoda <yoshihiro.shimoda.uh@...esas.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-renesas-soc@...r.kernel.org" 
        <linux-renesas-soc@...r.kernel.org>,
        Chris Paterson <Chris.Paterson2@...esas.com>,
        Biju Das <biju.das@...renesas.com>,
        Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@...renesas.com>
Subject: RE: [PATCH net-next v2 13/14] ravb: Update EMAC configuration mode
 comment



> -----Original Message-----
> From: Sergei Shtylyov <sergei.shtylyov@...il.com>
> Sent: 10 October 2021 10:49
> To: Biju Das <biju.das.jz@...renesas.com>; David S. Miller
> <davem@...emloft.net>; Jakub Kicinski <kuba@...nel.org>
> Cc: Sergey Shtylyov <s.shtylyov@....ru>; Geert Uytterhoeven
> <geert+renesas@...der.be>; Sergey Shtylyov <s.shtylyov@...russia.ru>; Adam
> Ford <aford173@...il.com>; Andrew Lunn <andrew@...n.ch>; Yuusuke Ashizuka
> <ashiduka@...itsu.com>; Yoshihiro Shimoda
> <yoshihiro.shimoda.uh@...esas.com>; netdev@...r.kernel.org; linux-renesas-
> soc@...r.kernel.org; Chris Paterson <Chris.Paterson2@...esas.com>; Biju
> Das <biju.das@...renesas.com>; Prabhakar Mahadev Lad <prabhakar.mahadev-
> lad.rj@...renesas.com>
> Subject: Re: [PATCH net-next v2 13/14] ravb: Update EMAC configuration
> mode comment
> 
> On 10.10.2021 12:37, Biju Das wrote:
> > Hi Sergey,
> >
> >> -----Original Message-----
> >> From: Sergei Shtylyov <sergei.shtylyov@...il.com>
> >> Sent: 10 October 2021 10:28
> >> To: Biju Das <biju.das.jz@...renesas.com>; David S. Miller
> >> <davem@...emloft.net>; Jakub Kicinski <kuba@...nel.org>
> >> Cc: Sergey Shtylyov <s.shtylyov@....ru>; Geert Uytterhoeven
> >> <geert+renesas@...der.be>; Sergey Shtylyov <s.shtylyov@...russia.ru>;
> >> Adam Ford <aford173@...il.com>; Andrew Lunn <andrew@...n.ch>; Yuusuke
> >> Ashizuka <ashiduka@...itsu.com>; Yoshihiro Shimoda
> >> <yoshihiro.shimoda.uh@...esas.com>; netdev@...r.kernel.org;
> >> linux-renesas- soc@...r.kernel.org; Chris Paterson
> >> <Chris.Paterson2@...esas.com>; Biju Das <biju.das@...renesas.com>;
> >> Prabhakar Mahadev Lad <prabhakar.mahadev- lad.rj@...renesas.com>
> >> Subject: Re: [PATCH net-next v2 13/14] ravb: Update EMAC
> >> configuration mode comment
> >>
> >> On 10.10.2021 10:29, Biju Das wrote:
> >>
> >>> Update EMAC configuration mode comment from "PAUSE prohibition"
> >>> to "EMAC Mode: PAUSE prohibition; Duplex; TX; RX; CRC Pass Through;
> >>> Promiscuous".
> >>>
> >>> Signed-off-by: Biju Das <biju.das.jz@...renesas.com>
> >>> Suggested-by: Sergey Shtylyov <s.shtylyov@....ru>
> >>> ---
> >>> v1->v2:
> >>>    * No change
> >>> V1:
> >>>    * New patch.
> >>> ---
> >>>    drivers/net/ethernet/renesas/ravb_main.c | 2 +-
> >>>    1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c
> >>> b/drivers/net/ethernet/renesas/ravb_main.c
> >>> index 9a770a05c017..b78aca235c37 100644
> >>> --- a/drivers/net/ethernet/renesas/ravb_main.c
> >>> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> >>> @@ -519,7 +519,7 @@ static void ravb_emac_init_gbeth(struct
> >>> net_device
> >> *ndev)
> >>>    	/* Receive frame limit set register */
> >>>    	ravb_write(ndev, GBETH_RX_BUFF_MAX + ETH_FCS_LEN, RFLR);
> >>>
> >>> -	/* PAUSE prohibition */
> >>> +	/* EMAC Mode: PAUSE prohibition; Duplex; TX; RX; CRC Pass Through;
> >>> +Promiscuous */
> >>
> >>      Promiscuous mode, really? Why?!
> >
> > This is TOE related,

I meant the context here is TOE register related. That is what I meant.

> 
>     The promiscuous mode is supported by _all_ Ethernet controllers, I
> think.
> 
> > and is recommendation from BSP team.
> 
>     On what grounds?

The reference implementation has this on. Any way it is good catch. 
I will turn it off and check.

by looking at the RJ LED's there is not much activity and packet statistics also show not much activity by default.

How can we check, it is overloading the controller? So that I can compare with and without this setting

> 
> > If you think it is wrong.
> > I can take this out. Please let me know. Currently the board is booting
> and everything works without issues.
> 
>     Please do take it out. It'll needlessly overload the controller when
> there's much traffic on the local network.


I can see much activity only on RJ45 LED's when I call tcpdump or by setting IP link set eth0 promisc on.
Otherwise there is no traffic at all.

Regards,
Biju

> 
> > The meaning of promiscuous in H/W manual as follows.
> 
>     I know what the promiscuous mode is. :-)
>     It's needed by things like 'tcpdump' and normally shoild be off.
> 
> > Promiscuous Mode
> > 1: All the frames except for PAUSE frame are received. Self-addressed
> > unicast, different address unicast, multicast, and broadcast frames
> > are all transferred to TOE. PAUSE frame reception is controlled by PFR
> bit.
> > 0: Self-addressed unicast, multicast, and broadcast frames are
> > received, then transferred to TOE.



> >
> > Regards,
> > Biju
> 
> MBR, Sergey