Re: [PATCH 0/2] igb/ixgbe: Fix ordering of SR-IOV teardown
On Wed, 2015-07-29 at 14:31 -0700, David Miller wrote: From: Alex Williamson alex.william...@redhat.com Date: Wed, 29 Jul 2015 13:33:07 -0600 I expect that's because of this patch that's in Jeff's dev-queue branch: http://git.kernel.org/cgit/linux/kernel/git/jkirsher/next-queue.git/commit/?h=dev-queueid=ddf766a812a13eca1116b5905e902184904266f9 I based these patches off that branch, assuming they'd take the same route and avoid the merge conflict. If you'd rather take these, I'll be happy to respin. Apologies for not noting the base branch in the series. Thanks, No, that's fine, this would normally go via Jeff's tree anyways. I just didn't see him take it so I assumed that it should go via me. Sorry, was on vacation last week and cell coverage was spotty where I was at. I have picked up the series. signature.asc Description: This is a digitally signed message part
Re: [PATCH 0/2] igb/ixgbe: Fix ordering of SR-IOV teardown
From: Alex Williamson alex.william...@redhat.com Date: Wed, 29 Jul 2015 13:33:07 -0600 I expect that's because of this patch that's in Jeff's dev-queue branch: http://git.kernel.org/cgit/linux/kernel/git/jkirsher/next-queue.git/commit/?h=dev-queueid=ddf766a812a13eca1116b5905e902184904266f9 I based these patches off that branch, assuming they'd take the same route and avoid the merge conflict. If you'd rather take these, I'll be happy to respin. Apologies for not noting the base branch in the series. Thanks, No, that's fine, this would normally go via Jeff's tree anyways. I just didn't see him take it so I assumed that it should go via me. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/2] igb/ixgbe: Fix ordering of SR-IOV teardown
From: Alex Williamson alex.william...@redhat.com Date: Mon, 27 Jul 2015 17:18:28 -0600 When running a Windows 2012 R2 guest with a pair of VFs assigned through vfio-pci, we run into a problem trying to hot-unplug those VFs after the PF has unregistered the netdev. This is a common scenario if the PF is unbound from the driver while VFs are active. In the case of igb, the resulting guest behavior differs slightly between the Microsoft provided and Intel add-on guest drivers. With the Microsoft driver, the guest seems to stumble through ejecting both VFs, but takes longer than normal to do so. With the Intel drivers, only one VF is unplugged, but Device Manager still shows it as present. The second VF is non-functional but also still shown in Device Manager. At this point, the guest is in such a state that it will not cleanly shutdown. With ixgbe VFs, both the Microsoft and Intel drivers take on this latter behavior. For both, I've found that disabling SR-IOV before unregistering the PF netdev device allows the hot-unplug to proceed without interruption or further ill behavior in the guest. This is true regardless of which driver is used. I don't fully understand what dependency is broken by unregistering the netdev prior to disabling SR-IOV, but I also don't see the benefit in delaying SR-IOV teardown in this call path. It could potentially be moved even earlier, but I'll let those more familiar with the hardware and code make that determination. In any case, the VM behavior is substantially improved by this slight re-ordering. I don't have an i40e for testing, but it already appears to disable SR-IOV much earlier in the unbind path, so I wouldn't expect to find similar issues. Thanks, Patch #2 does not apply cleanly, please respin this series against my 'net' GIT tree, thanks. -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 0/2] igb/ixgbe: Fix ordering of SR-IOV teardown
On Wed, 2015-07-29 at 12:16 -0700, David Miller wrote: From: Alex Williamson alex.william...@redhat.com Date: Mon, 27 Jul 2015 17:18:28 -0600 When running a Windows 2012 R2 guest with a pair of VFs assigned through vfio-pci, we run into a problem trying to hot-unplug those VFs after the PF has unregistered the netdev. This is a common scenario if the PF is unbound from the driver while VFs are active. In the case of igb, the resulting guest behavior differs slightly between the Microsoft provided and Intel add-on guest drivers. With the Microsoft driver, the guest seems to stumble through ejecting both VFs, but takes longer than normal to do so. With the Intel drivers, only one VF is unplugged, but Device Manager still shows it as present. The second VF is non-functional but also still shown in Device Manager. At this point, the guest is in such a state that it will not cleanly shutdown. With ixgbe VFs, both the Microsoft and Intel drivers take on this latter behavior. For both, I've found that disabling SR-IOV before unregistering the PF netdev device allows the hot-unplug to proceed without interruption or further ill behavior in the guest. This is true regardless of which driver is used. I don't fully understand what dependency is broken by unregistering the netdev prior to disabling SR-IOV, but I also don't see the benefit in delaying SR-IOV teardown in this call path. It could potentially be moved even earlier, but I'll let those more familiar with the hardware and code make that determination. In any case, the VM behavior is substantially improved by this slight re-ordering. I don't have an i40e for testing, but it already appears to disable SR-IOV much earlier in the unbind path, so I wouldn't expect to find similar issues. Thanks, Patch #2 does not apply cleanly, please respin this series against my 'net' GIT tree, thanks. I expect that's because of this patch that's in Jeff's dev-queue branch: http://git.kernel.org/cgit/linux/kernel/git/jkirsher/next-queue.git/commit/?h=dev-queueid=ddf766a812a13eca1116b5905e902184904266f9 I based these patches off that branch, assuming they'd take the same route and avoid the merge conflict. If you'd rather take these, I'll be happy to respin. Apologies for not noting the base branch in the series. Thanks, Alex -- To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
