On Fri, Jan 06, 2017 at 01:59:08PM -0800, Emil Tantilov wrote: >Enabling/disabling SRIOV via sysfs by echo-ing multiple values >simultaneously: > >echo 63 > /sys/class/net/ethX/device/sriov_numvfs& >echo 63 > /sys/class/net/ethX/device/sriov_numvfs > >sleep 5 > >echo 0 > /sys/class/net/ethX/device/sriov_numvfs& >echo 0 > /sys/class/net/ethX/device/sriov_numvfs > >Results in the following bug: > >kernel BUG at drivers/pci/iov.c:495! >invalid opcode: 0000 [#1] SMP >CPU: 1 PID: 8050 Comm: bash Tainted: G W 4.9.0-rc7-net-next #2092 >RIP: 0010:[<ffffffff813b1647>] > [<ffffffff813b1647>] pci_iov_release+0x57/0x60 > >Call Trace: > [<ffffffff81391726>] pci_release_dev+0x26/0x70 > [<ffffffff8155be6e>] device_release+0x3e/0xb0 > [<ffffffff81365ee7>] kobject_cleanup+0x67/0x180 > [<ffffffff81365d9d>] kobject_put+0x2d/0x60 > [<ffffffff8155bc27>] put_device+0x17/0x20 > [<ffffffff8139c08a>] pci_dev_put+0x1a/0x20 > [<ffffffff8139cb6b>] pci_get_dev_by_id+0x5b/0x90 > [<ffffffff8139cca5>] pci_get_subsys+0x35/0x40 > [<ffffffff8139ccc8>] pci_get_device+0x18/0x20 > [<ffffffff8139ccfb>] pci_get_domain_bus_and_slot+0x2b/0x60 > [<ffffffff813b09e7>] pci_iov_remove_virtfn+0x57/0x180 > [<ffffffff813b0b95>] pci_disable_sriov+0x65/0x140 > [<ffffffffa00a1af7>] ixgbe_disable_sriov+0xc7/0x1d0 [ixgbe] > [<ffffffffa00a1e9d>] ixgbe_pci_sriov_configure+0x3d/0x170 [ixgbe] > [<ffffffff8139d28c>] sriov_numvfs_store+0xdc/0x130 >... >RIP [<ffffffff813b1647>] pci_iov_release+0x57/0x60 > >Use the existing mutex lock to protect each enable/disable operation. > >-v2: move the existing lock from protecting the config of the IOV bus >to protecting the writes to sriov_numvfs in sysfs without maintaining >a "locked" version of pci_iov_add/remove_virtfn(). >As suggested by Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx> > >CC: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> >Signed-off-by: Emil Tantilov <emil.s.tantilov@xxxxxxxxx> >--- Reviewed-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx> -- 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
