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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sun, 20 Dec 2020 20:53:58 -0800 From: Florian Fainelli <f.fainelli@...il.com> To: Vladimir Oltean <vladimir.oltean@....com> Cc: "David S. Miller" <davem@...emloft.net>, Jakub Kicinski <kuba@...nel.org>, Andrew Lunn <andrew@...n.ch>, Vivien Didelot <vivien.didelot@...il.com>, "bcm-kernel-feedback-list@...adcom.com" <bcm-kernel-feedback-list@...adcom.com>, "netdev@...r.kernel.org" <netdev@...r.kernel.org> Subject: Re: [RFC PATCH net-next 3/4] net: systemport: use standard netdevice notifier to detect DSA presence On 12/19/2020 4:12 AM, Vladimir Oltean wrote: > On Fri, Dec 18, 2020 at 08:08:56PM -0800, Florian Fainelli wrote: >> On 12/18/2020 2:38 PM, Vladimir Oltean wrote: >>> The SYSTEMPORT driver maps each port of the embedded Broadcom DSA switch >>> port to a certain queue of the master Ethernet controller. For that it >>> currently uses a dedicated notifier infrastructure which was added in >>> commit 60724d4bae14 ("net: dsa: Add support for DSA specific notifiers"). >>> >>> However, since commit 2f1e8ea726e9 ("net: dsa: link interfaces with the >>> DSA master to get rid of lockdep warnings"), DSA is actually an upper of >>> the Broadcom SYSTEMPORT as far as the netdevice adjacency lists are >>> concerned. So naturally, the plain NETDEV_CHANGEUPPER net device notifiers >>> are emitted. It looks like there is enough API exposed by DSA to the >>> outside world already to make the call_dsa_notifiers API redundant. So >>> let's convert its only user to plain netdev notifiers. >>> >>> Signed-off-by: Vladimir Oltean <vladimir.oltean@....com> >> >> The CHANGEUPPER has a slightly different semantic than the current DSA >> notifier, and so events that would look like this during >> bcm_sysport_init_tx_ring() (good): >> >> [ 6.781064] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=0 >> [ 6.789214] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=0 >> [ 6.797337] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=0 >> [ 6.805464] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=0 >> [ 6.813583] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=1 >> [ 6.821701] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=1 >> [ 6.829819] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=1 >> [ 6.837944] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=1 >> [ 6.846063] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=2 >> [ 6.854183] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=2 >> [ 6.862303] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=2 >> [ 6.870425] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=2 >> [ 6.878544] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=5 >> [ 6.886663] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=5 >> [ 6.894783] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=5 >> [ 6.902906] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=5 >> >> now we are getting (bad): >> >> [ 6.678157] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=0 >> [ 6.686302] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=0 >> [ 6.694434] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=0 >> [ 6.702554] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=0 >> [ 6.710679] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=0 >> [ 6.718797] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=0 >> [ 6.726914] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=0 >> [ 6.735033] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=0 >> [ 6.743156] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=1 >> [ 6.751275] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=1 >> [ 6.759395] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=1 >> [ 6.767514] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=1 >> [ 6.775636] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=0,port=1 >> [ 6.783754] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=1,port=1 >> [ 6.791874] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=2,port=1 >> [ 6.799992] brcm-systemport 9300000.ethernet eth0: TDMA cfg, size=256, switch q=3,port=1 >> >> Looking further in bcm_sysport_map_queues() we are getting the following: >> >> 6.223042] brcm-systemport 9300000.ethernet eth0: mapping q=0, p=0 >> [ 6.229369] brcm-systemport 9300000.ethernet eth0: mapping q=1, p=0 >> [ 6.235659] brcm-systemport 9300000.ethernet eth0: mapping q=2, p=0 >> [ 6.241945] brcm-systemport 9300000.ethernet eth0: mapping q=3, p=0 >> [ 6.248232] brcm-systemport 9300000.ethernet eth0: mapping q=4, p=0 >> [ 6.254519] brcm-systemport 9300000.ethernet eth0: mapping q=5, p=0 >> [ 6.260805] brcm-systemport 9300000.ethernet eth0: mapping q=6, p=0 >> [ 6.267092] brcm-systemport 9300000.ethernet eth0: mapping q=7, p=0 >> >> which means that the call to netif_set_real_num_tx_queues() that is >> executed for the SYSTEMPORT Lite is not taking effect because it is >> after the register_netdevice(). Insead of using a CHANGEUPPER notifier, >> we can use a REGISTER notifier event and doing that works just fine with >> the same semantics as the DSA notifier being removed. This incremental >> patch on top of your patch works for me (tm): >> >> https://github.com/ffainelli/linux/commit/f5095ab5c1f31db133d62273928b224674626b75 > > This is odd, the netif_set_real_num_tx_queues() call should not fail or > be ignored even if the interface was registered. I had tested this already > on my enetc + felix combo on LS1028A. Yes that part is fine, see below. > > static int enetc_dsa_join(struct net_device *dev, > struct net_device *slave_dev) > { > int err; > > netdev_err(slave_dev, "Hello!\n"); > > err = netif_set_real_num_tx_queues(slave_dev, > slave_dev->num_tx_queues / 2); > if (err) > return err; > > netdev_err(slave_dev, "New number of real TX queues: %d\n", > slave_dev->real_num_tx_queues); > > return 0; > } > > prints: > > [ 7.002328] mscc_felix 0000:00:00.5 swp0 (uninitialized): PHY [0000:00:00.3:10] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) > [ 7.021190] mscc_felix 0000:00:00.5 swp0: Hello! > [ 7.028657] mscc_felix 0000:00:00.5 swp0: New number of real TX queues: 4 > [ 7.035589] mscc_felix 0000:00:00.5 swp0: Hello! > [ 7.040380] mscc_felix 0000:00:00.5 swp0: New number of real TX queues: 4 > [ 7.290236] mscc_felix 0000:00:00.5 swp1 (uninitialized): PHY [0000:00:00.3:11] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) > [ 7.314383] mscc_felix 0000:00:00.5 swp1: Hello! > [ 7.321292] mscc_felix 0000:00:00.5 swp1: New number of real TX queues: 4 > [ 7.328223] mscc_felix 0000:00:00.5 swp1: Hello! > [ 7.332967] mscc_felix 0000:00:00.5 swp1: New number of real TX queues: 4 > [ 7.574254] mscc_felix 0000:00:00.5 swp2 (uninitialized): PHY [0000:00:00.3:12] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) > [ 7.598431] mscc_felix 0000:00:00.5 swp2: Hello! > [ 7.605215] mscc_felix 0000:00:00.5 swp2: New number of real TX queues: 4 > [ 7.612145] mscc_felix 0000:00:00.5 swp2: Hello! > [ 7.616889] mscc_felix 0000:00:00.5 swp2: New number of real TX queues: 4 > [ 7.858868] mscc_felix 0000:00:00.5 swp3 (uninitialized): PHY [0000:00:00.3:13] driver [Microsemi GE VSC8514 SyncE] (irq=POLL) > [ 7.884240] mscc_felix 0000:00:00.5 swp3: Hello! > [ 7.891086] mscc_felix 0000:00:00.5 swp3: New number of real TX queues: 4 > [ 7.898018] mscc_felix 0000:00:00.5 swp3: Hello! > [ 7.902763] mscc_felix 0000:00:00.5 swp3: New number of real TX queues: 4 > > (I am not sure why the notifier is called twice though) This is the actual issue that messes up the queue assignment for bcmsysport because we assign queue/switch port pairs and don't really expect to be re-doing that once ring->inspect is set to true. > > You are saying that here: > > num_tx_queues = slave_dev->real_num_tx_queues; > > num_tx_queues remains assigned to 8? Does this mean that netif_set_real_num_tx_queues > has returned an error code? Can you check why? > The call to netif_set_real_num_tx_queues() succeeds and slave_dev->real_num_tx_queues is changed to 4 accordingly. The loop that assigns the internal queue mapping (priv->ring_map) is correctly limited to 4, however we get two calls per switch port instead of one. I did not have much time to debug why we get called twice but I will be looking into this tomorrow. -- Florian
Powered by blists - more mailing lists