Subject: Re: [PATCH -next] smsc911x: Fix crash seen if neither ACPI nor OF is configured or used

From: Tony Lindgren <[email-masked]>
Date: Wed, 26 Aug 2015 10:04:10 -0700

Hi,

* Guenter Roeck <[email-masked]> [150817 13:48]:
> Commit 0b50dc4fc971 ("Convert smsc911x to use ACPI as well as DT") makes
> the call to smsc911x_probe_config() unconditional, and no longer fails if
> there is no device node. device_get_phy_mode() is called unconditionally,
> and if there is no phy node configured returns an error code. This error
> code is assigned to phy_interface, and interpreted elsewhere in the code
> as valid phy mode. This in turn causes qemu to crash when running a
> variant of realview_pb_defconfig.
> 
> 	qemu: hardware error: lan9118_read: Bad reg 0x86
> 
> Fixes: 0b50dc4fc971 ("Convert smsc911x to use ACPI as well as DT")
> Cc: Jeremy Linton <[email-masked]>
> Cc Graeme Gregory <[email-masked]>
> Signed-off-by: Guenter Roeck <[email-masked]>
> ---
>  drivers/net/ethernet/smsc/smsc911x.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c
> index 0f21aa3bb537..34f97684506b 100644
> --- a/drivers/net/ethernet/smsc/smsc911x.c
> +++ b/drivers/net/ethernet/smsc/smsc911x.c
> @@ -2367,12 +2367,17 @@ static const struct smsc911x_ops shifted_smsc911x_ops = {
>  static int smsc911x_probe_config(struct smsc911x_platform_config *config,
>  				 struct device *dev)
>  {
> +	int phy_interface;
>  	u32 width = 0;
>  
>  	if (!dev)
>  		return -ENODEV;
>  
> -	config->phy_interface = device_get_phy_mode(dev);
> +	phy_interface = device_get_phy_mode(dev);
> +	if (phy_interface < 0)
> +		return phy_interface;
> +
> +	config->phy_interface = phy_interface;
>  
>  	device_get_mac_address(dev, config->mac, ETH_ALEN);

Looks like this change makes at least omap boards using smsc911x
fail with -22 for me in Linux next.

Do any of the the device tree configured smsc911x devices actually
have a phy configured?

Regards,

Tony