> -----Original Message----- > From: Mohammed Gamal [mailto:mga...@redhat.com] > Sent: Tuesday, January 23, 2018 4:34 AM > To: netdev@vger.kernel.org > Cc: linux-ker...@vger.kernel.org; de...@linuxdriverproject.org; KY > Srinivasan <k...@microsoft.com>; Haiyang Zhang <haiya...@microsoft.com>; > Stephen Hemminger <sthem...@microsoft.com>; vkuzn...@redhat.com; > cav...@redhat.com; ot...@redhat.com; Mohammed Gamal > <mga...@redhat.com> > Subject: [RFC PATCH 0/2] hv_netvsc: Fix shutdown regression on Win2012 > hosts > > Commit 0cf737808ae7 ("hv_netvsc: netvsc_teardown_gpadl() split") > introduced a regression that caused VMs not to shutdown after > netvsc_device_remove() is called. This is caused by GPADL teardown > sequence change, and while that was necessary to fix issues with Win2016 > hosts, it did introduce a regression for earlier versions. > > Prior to commit 0cf737808 the call sequence in netvsc_device_remove() was > as follows (as implemented in netvsc_destroy_buf()): > 1- Send NVSP_MSG1_TYPE_REVOKE_RECV_BUF message > 2- Teardown receive buffer GPADL > 3- Send NVSP_MSG1_TYPE_REVOKE_SEND_BUF message > 4- Teardown send buffer GPADL > 5- Close vmbus > > This didn't work for WS2016 hosts. Commit 0cf737808 split > netvsc_destroy_buf() into two functions and rearranged the order as follows > 1- Send NVSP_MSG1_TYPE_REVOKE_RECV_BUF message > 2- Send NVSP_MSG1_TYPE_REVOKE_SEND_BUF message > 3- Close vmbus > 4- Teardown receive buffer GPADL > 5- Teardown send buffer GPADL > > That worked well for WS2016 hosts, but for WS2012 hosts it prevented VMs > from shutting down. > > This patch series works around this problem. The first patch splits > netvsc_revoke_buf() and netvsc_teardown_gpadl() into two finer grained > functions for tearing down send and receive buffers individally. The second > patch uses the finer grained functions to implement the teardown sequence > according to the host's version. We keep the behavior introduced in > 0cf737808ae7 for Windows > 2016 hosts, while we re-introduce the old sequence for earlier verions. > > Mohammed Gamal (2): > hv_netvsc: Split netvsc_revoke_buf() and netvsc_teardown_gpadl() > hv_netvsc: Change GPADL teardown order according to Hyper-V version > > drivers/net/hyperv/netvsc.c | 50 > +++++++++++++++++++++++++++++++++++++-------- > 1 file changed, 42 insertions(+), 8 deletions(-)
Thank you for the patches. We are testing them internally. - Haiyang
