diff options
| author | Emil Tantilov <emil.s.tantilov@intel.com> | 2017-01-06 13:59:08 -0800 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2017-02-03 13:42:38 -0600 |
| commit | 5b0948dfe138f0837699f46f5877f4f81c252dac (patch) | |
| tree | eb67c2325c5dea87be81c16ce19b872dd153ac6a /drivers/pci/iov.c | |
| parent | 7184f5b451cf3dc61de79091d235b5d2bba2782d (diff) | |
| download | lwn-5b0948dfe138f0837699f46f5877f4f81c252dac.tar.gz lwn-5b0948dfe138f0837699f46f5877f4f81c252dac.zip | |
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>
Diffstat (limited to 'drivers/pci/iov.c')
| -rw-r--r-- | drivers/pci/iov.c | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 47227820406d..2479ae876482 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -124,7 +124,6 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id, int reset) struct pci_sriov *iov = dev->sriov; struct pci_bus *bus; - mutex_lock(&iov->dev->sriov->lock); bus = virtfn_add_bus(dev->bus, pci_iov_virtfn_bus(dev, id)); if (!bus) goto failed; @@ -162,7 +161,6 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id, int reset) __pci_reset_function(virtfn); pci_device_add(virtfn, virtfn->bus); - mutex_unlock(&iov->dev->sriov->lock); pci_bus_add_device(virtfn); sprintf(buf, "virtfn%u", id); @@ -181,12 +179,10 @@ failed2: sysfs_remove_link(&dev->dev.kobj, buf); failed1: pci_dev_put(dev); - mutex_lock(&iov->dev->sriov->lock); pci_stop_and_remove_bus_device(virtfn); failed0: virtfn_remove_bus(dev->bus, bus); failed: - mutex_unlock(&iov->dev->sriov->lock); return rc; } @@ -195,7 +191,6 @@ void pci_iov_remove_virtfn(struct pci_dev *dev, int id, int reset) { char buf[VIRTFN_ID_LEN]; struct pci_dev *virtfn; - struct pci_sriov *iov = dev->sriov; virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), pci_iov_virtfn_bus(dev, id), @@ -218,10 +213,8 @@ void pci_iov_remove_virtfn(struct pci_dev *dev, int id, int reset) if (virtfn->dev.kobj.sd) sysfs_remove_link(&virtfn->dev.kobj, "physfn"); - mutex_lock(&iov->dev->sriov->lock); pci_stop_and_remove_bus_device(virtfn); virtfn_remove_bus(dev->bus, virtfn->bus); - mutex_unlock(&iov->dev->sriov->lock); /* balance pci_get_domain_bus_and_slot() */ pci_dev_put(virtfn); |