On 29.12.2018 03:42, Florian Fainelli wrote: > Le 12/24/18 à 3:21 AM, Heiner Kallweit a écrit : >> phy_device_create() uses request_module() to load the PHY driver module >> based on the PHY ID of the device. There is some timing issue which >> sometimes prevents the PHY driver to bind to the device. In such cases >> the genphy driver is used what can cause problems if genphy isn't >> compatible with the respective PHY. >> It turned out that the first fix can fix the issue in some but not all >> cases. Moving the call to device_initialize() before the call to >> request_module() was reported to fix the issue. >> I can't explain where the root cause of the issue is and why this fix >> works. AFAICS device_initialize() just initializes the device struct >> w/o doing anything that could interfere with e.g. bus_add_driver(). >> This patch removes the first preliminary fix attempt. > > Humm but phy_device is comprised of a mdio_device on which the actual > matching is done, so you do have to call device_initialize() first in > order for the phy_device instance to have its companion mdio_device's > kobject to be properly initialized. > > Out of curiosity, do any of the people who tested that change have the > ability to run a kernel with list/kobject debugging enabled so we can > learn a bit more about the problematic code path? >> One or two can build a kernel and test if they are given a patch and instructions. The other option is to ask Hans from Redhat to build a test kernel and distribute it as rpm to users who want to test. See also history of the bug ticket.
Last status is that I provided a patch which creates some debug output and Hans built a test kernel. However most likely we will get feedback only beginning of January when more people are back from holidays. >> Reference: >> https://bugzilla.redhat.com/show_bug.cgi?id=1650984 >>
