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Date:   Sat, 12 Feb 2022 10:00:10 +0000
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Jeremy Linton <jeremy.linton@arm.com>
Cc:     netdev@vger.kernel.org, mw@semihalf.com, davem@davemloft.net,
        kuba@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [BUG/PATCH v2] net: mvpp2: always set port pcs ops
Message-ID: <YgeFKsRjlxNiJbSa@shell.armlinux.org.uk>
References: <20220212003454.3214726-1-jeremy.linton@arm.com>
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In-Reply-To: <20220212003454.3214726-1-jeremy.linton@arm.com>
Sender: Russell King (Oracle) <linux@armlinux.org.uk>
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On Fri, Feb 11, 2022 at 06:34:54PM -0600, Jeremy Linton wrote:
> Booting a MACCHIATObin with 5.17, the system OOPs with
> a null pointer deref when the network is started. This
> is caused by the pcs->ops structure being null in
> mcpp2_acpi_start() when it tries to call pcs_config().
> 
> Hoisting the code which sets pcs_gmac.ops and pcs_xlg.ops,
> assuring they are always set, fixes the problem.
> 
> The OOPs looks like:
> [   18.687760] Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000010
> [   18.698561] Mem abort info:
> [   18.698564]   ESR = 0x96000004
> [   18.698567]   EC = 0x25: DABT (current EL), IL = 32 bits
> [   18.709821]   SET = 0, FnV = 0
> [   18.714292]   EA = 0, S1PTW = 0
> [   18.718833]   FSC = 0x04: level 0 translation fault
> [   18.725126] Data abort info:
> [   18.729408]   ISV = 0, ISS = 0x00000004
> [   18.734655]   CM = 0, WnR = 0
> [   18.738933] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000111bbf000
> [   18.745409] [0000000000000010] pgd=0000000000000000, p4d=0000000000000000
> [   18.752235] Internal error: Oops: 96000004 [#1] SMP
> [   18.757134] Modules linked in: rfkill ip_set nf_tables nfnetlink qrtr sunrpc vfat fat omap_rng fuse zram xfs crct10dif_ce mvpp2 ghash_ce sbsa_gwdt phylink xhci_plat_hcd ahci_plam
> [   18.773481] CPU: 0 PID: 681 Comm: NetworkManager Not tainted 5.17.0-0.rc3.89.fc36.aarch64 #1
> [   18.781954] Hardware name: Marvell                         Armada 7k/8k Family Board      /Armada 7k/8k Family Board      , BIOS EDK II Jun  4 2019
> [   18.795222] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> [   18.802213] pc : mvpp2_start_dev+0x2b0/0x300 [mvpp2]
> [   18.807208] lr : mvpp2_start_dev+0x298/0x300 [mvpp2]
> [   18.812197] sp : ffff80000b4732c0
> [   18.815522] x29: ffff80000b4732c0 x28: 0000000000000000 x27: ffffccab38ae57f8
> [   18.822689] x26: ffff6eeb03065a10 x25: ffff80000b473a30 x24: ffff80000b4735b8
> [   18.829855] x23: 0000000000000000 x22: 00000000000001e0 x21: ffff6eeb07b6ab68
> [   18.837021] x20: ffff6eeb07b6ab30 x19: ffff6eeb07b6a9c0 x18: 0000000000000014
> [   18.844187] x17: 00000000f6232bfe x16: ffffccab899b1dc0 x15: 000000006a30f9fa
> [   18.851353] x14: 000000003b77bd50 x13: 000006dc896f0e8e x12: 001bbbfccfd0d3a2
> [   18.858519] x11: 0000000000001528 x10: 0000000000001548 x9 : ffffccab38ad0fb0
> [   18.865685] x8 : ffff80000b473330 x7 : 0000000000000000 x6 : 0000000000000000
> [   18.872851] x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80000b4732f8
> [   18.880017] x2 : 000000000000001a x1 : 0000000000000002 x0 : ffff6eeb07b6ab68
> [   18.887183] Call trace:
> [   18.889637]  mvpp2_start_dev+0x2b0/0x300 [mvpp2]
> [   18.894279]  mvpp2_open+0x134/0x2b4 [mvpp2]
> [   18.898483]  __dev_open+0x128/0x1e4
> [   18.901988]  __dev_change_flags+0x17c/0x1d0
> [   18.906187]  dev_change_flags+0x30/0x70
> [   18.910038]  do_setlink+0x278/0xa7c
> [   18.913540]  __rtnl_newlink+0x44c/0x7d0
> [   18.917391]  rtnl_newlink+0x5c/0x8c
> [   18.920892]  rtnetlink_rcv_msg+0x254/0x314
> [   18.925006]  netlink_rcv_skb+0x48/0x10c
> [   18.928858]  rtnetlink_rcv+0x24/0x30
> [   18.932449]  netlink_unicast+0x290/0x2f4
> [   18.936386]  netlink_sendmsg+0x1d0/0x41c
> [   18.940323]  sock_sendmsg+0x60/0x70
> [   18.943825]  ____sys_sendmsg+0x248/0x260
> [   18.947762]  ___sys_sendmsg+0x74/0xa0
> [   18.951438]  __sys_sendmsg+0x64/0xcc
> [   18.955027]  __arm64_sys_sendmsg+0x30/0x40
> [   18.959140]  invoke_syscall+0x50/0x120
> [   18.962906]  el0_svc_common.constprop.0+0x4c/0xf4
> [   18.967629]  do_el0_svc+0x30/0x9c
> [   18.970958]  el0_svc+0x28/0xb0
> [   18.974025]  el0t_64_sync_handler+0x10c/0x140
> [   18.978400]  el0t_64_sync+0x1a4/0x1a8
> [   18.982078] Code: 52800004 b9416262 aa1503e0 52800041 (f94008a5)
> [   18.988196] ---[ end trace 0000000000000000 ]---
> 
> Fixes: cff056322372 ("net: mvpp2: use .mac_select_pcs() interface")
> Suggested-by: Russel King (Oracle) <rmk+kernel@armlinux.org.uk>

Please spell my name correctly, especially in attributations. I really
don't want this committed with this mistake.

> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
> ---
>  drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index 7cdbf8b8bbf6..1a835b48791b 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -6870,6 +6870,9 @@ static int mvpp2_port_probe(struct platform_device *pdev,
>  	dev->max_mtu = MVPP2_BM_JUMBO_PKT_SIZE;
>  	dev->dev.of_node = port_node;
>  
> +	port->pcs_gmac.ops = &mvpp2_phylink_gmac_pcs_ops;
> +	port->pcs_xlg.ops = &mvpp2_phylink_xlg_pcs_ops;
> +
>  	if (!mvpp2_use_acpi_compat_mode(port_fwnode)) {
>  		port->phylink_config.dev = &dev->dev;
>  		port->phylink_config.type = PHYLINK_NETDEV;
> @@ -6940,9 +6943,6 @@ static int mvpp2_port_probe(struct platform_device *pdev,
>  				  port->phylink_config.supported_interfaces);
>  		}
>  
> -		port->pcs_gmac.ops = &mvpp2_phylink_gmac_pcs_ops;
> -		port->pcs_xlg.ops = &mvpp2_phylink_xlg_pcs_ops;
> -
>  		phylink = phylink_create(&port->phylink_config, port_fwnode,
>  					 phy_mode, &mvpp2_phylink_ops);
>  		if (IS_ERR(phylink)) {
> -- 
> 2.34.1
> 
> 

-- 
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