I bisected again, and again it came back to that mount point change. This seems so bizarre.
$ git bisect log # bad: [6d4f0a79e5a307b6fd3ee3cc5bbb2fcb701b09db] UBUNTU: Ubuntu-4.4.0-57.78 # good: [db5f146d309e70067dae57798c9ea679af835aa7] UBUNTU: Ubuntu-4.4.0-53.74 git bisect start 'Ubuntu-4.4.0-57.78' 'Ubuntu-4.4.0-53.74' # bad: [02bf412367b827aa5be05a315088ef5fdcf267ca] dmaengine: at_xdmac: fix spurious flag status for mem2mem transfers git bisect bad 02bf412367b827aa5be05a315088ef5fdcf267ca # bad: [1e089050b800ba7d6ba1bf5814827e6cca301ad5] smc91x: avoid self-comparison warning git bisect bad 1e089050b800ba7d6ba1bf5814827e6cca301ad5 # bad: [d7632bdaba3dd143eac3c80bb7e2b0f62259583d] xhci: use default USB_RESUME_TIMEOUT when resuming ports. git bisect bad d7632bdaba3dd143eac3c80bb7e2b0f62259583d # bad: [7942010de9a2fe39e72b84e628867f4ff29a70f2] libxfs: clean up _calc_dquots_per_chunk git bisect bad 7942010de9a2fe39e72b84e628867f4ff29a70f2 # good: [9d2524b0bdeb57f80d0279f6695a833606ad0597] UBUNTU: SAUCE: Bluetooth: decrease refcount after use git bisect good 9d2524b0bdeb57f80d0279f6695a833606ad0597 # bad: [fd4b5fa6e3487d15ede746f92601af008b2abbc0] mnt: Add a per mount namespace limit on the number of mounts git bisect bad fd4b5fa6e3487d15ede746f92601af008b2abbc0 # good: [f2109fe47ceb77647ef7d4f545efeba43d06fb64] videobuf2-v4l2: Verify planes array in buffer dequeueing git bisect good f2109fe47ceb77647ef7d4f545efeba43d06fb64 # good: [d5d9494d2092a7e571dee635ca254075912355c1] thinkpad_acpi: Add support for HKEY version 0x200 git bisect good d5d9494d2092a7e571dee635ca254075912355c1 # first bad commit: [fd4b5fa6e3487d15ede746f92601af008b2abbc0] mnt: Add a per mount namespace limit on the number of mounts -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1652348 Title: initrd dhcp fails / ignores valid response Status in linux package in Ubuntu: Incomplete Bug description: Between kernel versions 4.4.0-53 and 4.4.0-57 a bug has been (re?)introduced that is breaking dhcp booting in the initrd environment. This is stopping instances that use iscsi storage from being able to connect. Over serial console it outputs: IP-Config: no response after 2 secs - giving up IP-Config: ens2f0 hardware address 90:e2:ba:d1:36:38 mtu 1500 DHCP RARP IP-Config: ens2f1 hardware address 90:e2:ba:d1:36:39 mtu 1500 DHCP RARP IP-Config: no response after 3 secs - giving up with increasing delays until it fails. At which point a simple ipconfig -t dhcp -d "ens2f0" works. The console output is slightly garbled but should give you an idea: (initramfs) ipconfig -t dhcp -[ 728.379793] ixgbe 0000:13:00.0 ens2f0: changing MTU from 1500 to 9000 d "ens2f0" IP-Config: ens2f0 hardware address 90:e2:ba:d1:36:38 mtu 1500 DHCP RARP IP-Config: ens2f0 guessed broadcast address 10.0.1.255 IP-Config: ens2f0 complete (dhcp from 169.254.169.254): addres[ 728.980448] ixgbe 0000:13:00.0 ens2f0: detected SFP+: 3 s: 10.0.1.56 broadcast: 10.0.1.255 netmask: 255.255.255.0 gateway: 10.0.1.1 [ 729.148410] ixgbe 0000:13:00.0 ens2f0: NIC Link is Up 10 Gbps, Flow Control: RX/TX dns0 : 169.254.169.254 dns1 : 0.0.0.0 rootserver: 169.254.169.254 rootpath: filename : /ipxe.efi tcpdumps show that dhcp requests are being received from the host, and responses sent, but not accepted by the host. When the ipconfig command is issued manually, an identical dhcp request and response happens, only this time it is accepted. It doesn't appear to be that the messages are being sent and received incorrectly, just silently ignored by ipconfig. I was seeing this behaviour earlier this year, which I was able to fix by specifying "ip=dhcp" as a kernel parameter. About a month ago that was identified as causing us other problems (long story) and we dropped it, at which point we discovered the original bug was no longer an issue. Putting "ip=dhcp" back on with this kernel no longer fixes the problem. I've compared the two initrds and effectively the only thing that has changed between the two is the kernel components. I'm going to try and track back through kernel versions to see if I can find which version the fix happened in to maybe provide some additional context. I'll also attach copies of the initrds, packet captures etc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1652348/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
