On Tue, May 14, 2013 at 1:58 AM, Yan Burman <yanb@xxxxxxxxxxxx> wrote: > > >> -----Original Message----- >> From: netdev-owner@xxxxxxxxxxxxxxx [mailto:netdev-owner@xxxxxxxxxxxxxxx] >> On Behalf Of Yinghai Lu >> Sent: Tuesday, May 14, 2013 05:31 >> To: Bjorn Helgaas >> Cc: Gu Zheng; linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Yinghai >> Lu; netdev@xxxxxxxxxxxxxxx >> Subject: [PATCH 6/7] PCI: Make sure VF's driver get attached after PF's >> >> Found kernel try to load mlx4 drivers for VFs before PF's is really loaded when >> the drivers are built-in, and kernel command line include probe_vfs=63, >> num_vfs=63. >> >> It turns that it also happen for hotadd path even drivers are compiled as >> modules and if they loaded. Esp some VF share the same driver with PF. >> >> calling path: >> device driver probe >> ==> pci_enable_sriov >> ==> virtfn_add >> ==> pci_dev_add >> ==> pci_bus_device_add >> when pci_bus_device_add is called, the VF's driver will be attached. >> and at that time PF's driver does not finish yet. >> >> Need to move out pci_bus_device_add from virtfn_add and call it later. Fix >> the problem for two path, 1. hotadd path: use device_schedule_callback. >> 2. for booting path, use initcall to call that for all VF's. >> Index: linux-2.6/drivers/net/ethernet/mellanox/mlx4/main.c >> ================================================================= >> == >> --- linux-2.6.orig/drivers/net/ethernet/mellanox/mlx4/main.c >> +++ linux-2.6/drivers/net/ethernet/mellanox/mlx4/main.c >> @@ -2308,6 +2308,8 @@ slave_start: >> priv->pci_dev_data = pci_dev_data; >> pci_set_drvdata(pdev, dev); >> >> + pci_bus_add_device_vfs(pdev); >> + > > This seems wrong, since pci_bus_add_device_vfs() is being called for VF's as well as for PF when SRIOV is not enabled. > I can see that there are sanity checks in pci_bus_add_vf() that would prevent this code from doing damage, > but why schedule a callback that will do nothing if we can prevent scheduling altogether? > It would probably be better to do the following: > > + if (dev->flags & MLX4_FLAG_SRIOV) > + pci_bus_add_device_vfs(pdev); > + Yes, we can add that check. BTW, do you have any plan to make mlx4 support sriov_configure via sysfs? Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
