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| author | Zhang Yanmin <yanmin.zhang@intel.com> | 2006-06-02 12:35:43 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2006-06-21 12:00:01 -0700 |
| commit | d71374dafbba7ec3f67371d3b7e9f6310a588808 (patch) | |
| tree | 116dcd65fde3701d10fea954cdbd5bb063182b2c /drivers/pci/remove.c | |
| parent | 733a7fe12248072e1bca729c88a26298666f1956 (diff) | |
| download | lwn-d71374dafbba7ec3f67371d3b7e9f6310a588808.tar.gz lwn-d71374dafbba7ec3f67371d3b7e9f6310a588808.zip | |
[PATCH] PCI: fix race with pci_walk_bus and pci_destroy_dev
pci_walk_bus has a race with pci_destroy_dev. When cb is called
in pci_walk_bus, pci_destroy_dev might unlink the dev pointed by next.
Later on in the next loop, pointer next becomes NULL and cause
kernel panic.
Below patch against 2.6.17-rc4 fixes it by changing pci_bus_lock (spin_lock)
to pci_bus_sem (rw_semaphore).
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/pci/remove.c')
| -rw-r--r-- | drivers/pci/remove.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 1a6bf9de166f..99ffbd478b29 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -22,18 +22,18 @@ static void pci_destroy_dev(struct pci_dev *dev) pci_proc_detach_device(dev); pci_remove_sysfs_dev_files(dev); device_unregister(&dev->dev); - spin_lock(&pci_bus_lock); + down_write(&pci_bus_sem); list_del(&dev->global_list); dev->global_list.next = dev->global_list.prev = NULL; - spin_unlock(&pci_bus_lock); + up_write(&pci_bus_sem); } /* Remove the device from the device lists, and prevent any further * list accesses from this device */ - spin_lock(&pci_bus_lock); + down_write(&pci_bus_sem); list_del(&dev->bus_list); dev->bus_list.next = dev->bus_list.prev = NULL; - spin_unlock(&pci_bus_lock); + up_write(&pci_bus_sem); pci_free_resources(dev); pci_dev_put(dev); @@ -62,9 +62,9 @@ void pci_remove_bus(struct pci_bus *pci_bus) { pci_proc_detach_bus(pci_bus); - spin_lock(&pci_bus_lock); + down_write(&pci_bus_sem); list_del(&pci_bus->node); - spin_unlock(&pci_bus_lock); + up_write(&pci_bus_sem); pci_remove_legacy_files(pci_bus); class_device_remove_file(&pci_bus->class_dev, &class_device_attr_cpuaffinity); |