Ali Abdallah
2020-Dec-26 16:37 UTC
MII media status race condition causing fictitious link down
Hello, As I've sent a couple of patches to add support for Thinkpad USB-C gen2 to if_ure(4), I came across a very strange link random state change, causing dhclient to think the link went effectively down, which is not the case. First I thought that if_ure(4) doesn't play well with the new chip of the dock, but after lot of debugging, it turns out to be a nasty race condition in mii bus code [1]. I'm sending this mail to raise awareness about this issue. Apparently it exists since long time (I even remember having had this issue in the past on my older Thinkpad). [1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=252165 Regards, -- Ali Abdallah | SUSE L3 Engineer GPG fingerprint: 51A0 F4A0 C8CF C98F 842E A9A8 B945 56F8 1C85 D0D5