Note that the affected system has LRO turn on. The system crashed on :
#7 [ffff88042d683d30] invalid_op at ffffffff817f900e [exception RIP: vmxnet3_rq_rx_complete+3016] which is referring to line 1353 in "drivers/net/vmxnet3/vmxnet3_drv.c" : 0xffffffffc004e448 is in vmxnet3_rq_rx_complete (drivers/net/vmxnet3/vmxnet3_drv.c:1353). 1348 rcd->type == VMXNET3_CDTYPE_RXCOMP_LRO) { 1349 struct Vmxnet3_RxCompDescExt *rcdlro; 1350 rcdlro = (struct Vmxnet3_RxCompDescExt *)rcd; 1351 1352 segCnt = rcdlro->segCnt; ==> 1353 BUG_ON(segCnt <= 1); 1354 mss = rcdlro->mss; 1355 if (unlikely(segCnt <= 1)) 1356 segCnt = 0; 1357 } else { BUG_ON(condition) are used as a debugging help when something in the kernel goes wrong. The condition here execute BUG_ON if SegCnt is less or equal than (<=) 1. SegCnt being the "Number of aggregated packets" : # drivers/net/vmxnet3/vmxnet3_defs.h u8 segCnt; /* Number of aggregated packets */ Looking at the crashdump I can confirm that at the moment of the crash SegCnt was set to 1 : crash> * Vmxnet3_RxCompDescExt.segCnt ffff88042933ae00 segCnt = 1 '\001' According to commit "50219538ffc0493a2b451a3aa0191138ef8bfe9d", segCnt can be 1 for LRO packets and introduce the following change : - BUG_ON(segCnt <= 1); + WARN_ON_ONCE(segCnt == 0); [2] - commit 50219538ffc0493a2b451a3aa0191138ef8bfe9d -- Author: Shrikrishna Khare <skh...@vmware.com> Date: Wed Jun 8 07:40:53 2016 -0700 vmxnet3: segCnt can be 1 for LRO packets The device emulation may send segCnt of 1 for LRO packets. Signed-off-by: Shrikrishna Khare <skh...@vmware.com> --- ** Changed in: linux (Ubuntu) Assignee: (unassigned) => Eric Desrochers (slashd) ** Changed in: linux (Ubuntu) Status: Confirmed => In Progress -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1650635 Title: vmxnet3 driver causes kernel panic w/ kernel v4.4 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1650635/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs