Messages in this thread | | | Date | Wed, 08 Oct 2008 14:42:41 +0900 | From | Kenji Kaneshige <> | Subject | Re: [PATCH v4 02/15] PCI Hotplug: serialize pci_hp_register/deregister |
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I think we no longer need pci_hotplug_slot_list_lock with your patch.
Thanks, Kenji Kaneshige
Alex Chiang wrote: > Add explicit locking to pci_hp_register/deregister. For a given pci_slot, > we want to make sure that the pci_slot->hotplug pointer isn't being > changed from underneath us. > > Cc: jbarnes@virtuousgeek.org > Cc: kristen.c.accardi@intel.com > Cc: matthew@wil.cx > Cc: kaneshige.kenji@jp.fujitsu.com > Signed-off-by: Alex Chiang <achiang@hp.com> > --- > > drivers/pci/hotplug/pci_hotplug_core.c | 7 +++++++ > drivers/pci/slot.c | 4 ++-- > 2 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c > index 0e7a511..e00266b 100644 > --- a/drivers/pci/hotplug/pci_hotplug_core.c > +++ b/drivers/pci/hotplug/pci_hotplug_core.c > @@ -37,6 +37,7 @@ > #include <linux/init.h> > #include <linux/mount.h> > #include <linux/namei.h> > +#include <linux/mutex.h> > #include <linux/pci.h> > #include <linux/pci_hotplug.h> > #include <asm/uaccess.h> > @@ -554,6 +555,7 @@ out: > * > * Returns 0 if successful, anything else for an error. > */ > +static DEFINE_MUTEX(pci_hp_mutex); > int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, > const char *name) > { > @@ -583,7 +585,9 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, > if (IS_ERR(pci_slot)) > return PTR_ERR(pci_slot); > > + mutex_lock(&pci_hp_mutex); > if (pci_slot->hotplug) { > + mutex_unlock(&pci_hp_mutex); > dbg("%s: already claimed\n", __func__); > pci_destroy_slot(pci_slot); > return -EBUSY; > @@ -591,6 +595,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, > > slot->pci_slot = pci_slot; > pci_slot->hotplug = slot; > + mutex_unlock(&pci_hp_mutex); > > /* > * Allow pcihp drivers to override the ACPI_PCI_SLOT name. > @@ -635,6 +640,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) > if (temp != hotplug) > return -ENODEV; > > + mutex_lock(&pci_hp_mutex); > spin_lock(&pci_hotplug_slot_list_lock); > list_del(&hotplug->slot_list); > spin_unlock(&pci_hotplug_slot_list_lock); > @@ -645,6 +651,7 @@ int pci_hp_deregister(struct hotplug_slot *hotplug) > > hotplug->release(hotplug); > slot->hotplug = NULL; > + mutex_unlock(&pci_hp_mutex); > pci_destroy_slot(slot); > > return 0; > diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c > index 0c6db03..1fffb27 100644 > --- a/drivers/pci/slot.c > +++ b/drivers/pci/slot.c > @@ -164,10 +164,10 @@ placeholder: > pr_debug("%s: created pci_slot on %04x:%02x:%02x\n", > __func__, pci_domain_nr(parent), parent->number, slot_nr); > > - out: > +out: > up_write(&pci_bus_sem); > return slot; > - err: > +err: > kfree(slot); > slot = ERR_PTR(err); > goto out; > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > >
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