From 5b0948dfe138f0837699f46f5877f4f81c252dac Mon Sep 17 00:00:00 2001 From: Emil Tantilov Date: Fri, 6 Jan 2017 13:59:08 -0800 Subject: 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:[] [] pci_iov_release+0x57/0x60 Call Trace: [] pci_release_dev+0x26/0x70 [] device_release+0x3e/0xb0 [] kobject_cleanup+0x67/0x180 [] kobject_put+0x2d/0x60 [] put_device+0x17/0x20 [] pci_dev_put+0x1a/0x20 [] pci_get_dev_by_id+0x5b/0x90 [] pci_get_subsys+0x35/0x40 [] pci_get_device+0x18/0x20 [] pci_get_domain_bus_and_slot+0x2b/0x60 [] pci_iov_remove_virtfn+0x57/0x180 [] pci_disable_sriov+0x65/0x140 [] ixgbe_disable_sriov+0xc7/0x1d0 [ixgbe] [] ixgbe_pci_sriov_configure+0x3d/0x170 [ixgbe] [] sriov_numvfs_store+0xdc/0x130 ... RIP [] pci_iov_release+0x57/0x60 Use the existing mutex lock to protect each enable/disable operation. Signed-off-by: Emil Tantilov Signed-off-by: Bjorn Helgaas Reviewed-by: Gavin Shan CC: Alexander Duyck --- drivers/pci/pci.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/pci/pci.h') diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index cb17db242f30..8dd38e69d6f2 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -270,7 +270,7 @@ struct pci_sriov { u16 driver_max_VFs; /* max num VFs driver supports */ struct pci_dev *dev; /* lowest numbered PF */ struct pci_dev *self; /* this PF */ - struct mutex lock; /* lock for VF bus */ + struct mutex lock; /* lock for setting sriov_numvfs in sysfs */ resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */ }; -- cgit v1.2.3