diff options
| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2014-02-01 15:38:29 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-02-01 10:24:31 -0800 |
| commit | 04480094de7242d08bb62088e713fd7fe00443b4 (patch) | |
| tree | a8a9806a3f55f5343b6375743c8e107e800c6df6 | |
| parent | 8a1f006ad302ea178aefb1f8c67e679c696289e9 (diff) | |
Revert "PCI: Remove from bus_list and release resources in pci_release_dev()"
Revert commit ef83b0781a73 "PCI: Remove from bus_list and release
resources in pci_release_dev()" that made some nasty race conditions
become possible. For example, if a Thunderbolt link is unplugged
and then replugged immediately, the pci_release_dev() resulting from
the hot-remove code path may be racing with the hot-add code path
which after that commit causes various kinds of breakage to happen
(up to and including a hard crash of the whole system).
Moreover, the problem that commit ef83b0781a73 attempted to address
cannot happen any more after commit 8a4c5c329de7 "PCI: Check parent
kobject in pci_destroy_dev()", because pci_destroy_dev() will now
return immediately if it has already been executed for the given
device.
Note, however, that the invocation of msi_remove_pci_irq_vectors()
removed by commit ef83b0781a73 from pci_free_resources() along with
the other changes made by it is not added back because of subsequent
code changes depending on that modification.
Fixes: ef83b0781a73 (PCI: Remove from bus_list and release resources in pci_release_dev())
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/pci/probe.c | 21 | ||||
| -rw-r--r-- | drivers/pci/remove.c | 17 |
2 files changed, 19 insertions, 19 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 04796c056d12..6e34498ec9f0 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1208,18 +1208,6 @@ static void pci_release_capabilities(struct pci_dev *dev) pci_free_cap_save_buffers(dev); } -static void pci_free_resources(struct pci_dev *dev) -{ - int i; - - pci_cleanup_rom(dev); - for (i = 0; i < PCI_NUM_RESOURCES; i++) { - struct resource *res = dev->resource + i; - if (res->parent) - release_resource(res); - } -} - /** * pci_release_dev - free a pci device structure when all users of it are finished. * @dev: device that's been disconnected @@ -1229,14 +1217,9 @@ static void pci_free_resources(struct pci_dev *dev) */ static void pci_release_dev(struct device *dev) { - struct pci_dev *pci_dev = to_pci_dev(dev); - - down_write(&pci_bus_sem); - list_del(&pci_dev->bus_list); - up_write(&pci_bus_sem); - - pci_free_resources(pci_dev); + struct pci_dev *pci_dev; + pci_dev = to_pci_dev(dev); pci_release_capabilities(pci_dev); pci_release_of_node(pci_dev); pcibios_release_device(pci_dev); diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 4ff36bfa785e..8bd76c9ba21c 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -3,6 +3,18 @@ #include <linux/pci-aspm.h> #include "pci.h" +static void pci_free_resources(struct pci_dev *dev) +{ + int i; + + pci_cleanup_rom(dev); + for (i = 0; i < PCI_NUM_RESOURCES; i++) { + struct resource *res = dev->resource + i; + if (res->parent) + release_resource(res); + } +} + static void pci_stop_dev(struct pci_dev *dev) { pci_pme_active(dev, false); @@ -25,6 +37,11 @@ static void pci_destroy_dev(struct pci_dev *dev) device_del(&dev->dev); + down_write(&pci_bus_sem); + list_del(&dev->bus_list); + up_write(&pci_bus_sem); + + pci_free_resources(dev); put_device(&dev->dev); } |