Commits
Emil Tantilov committed 5b0948dfe13
PCI: Lock each enable/disable num_vfs operation in sysfs 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. Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com> CC: Alexander Duyck <alexander.h.duyck@intel.com>