| Message ID | 14676899.LOmsodapl3@vostro.rjw.lan (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Sat, Feb 1, 2014 at 6:38 AM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > > Updated revert follows. I'm taking this directly, since I'll cut rc1 tomorrow (or maybe later today). Linus -- 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
On Sat, Feb 01, 2014 at 03:38:29PM +0100, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Subject: 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> Thanks, that fixes the problem I'm seeing. -- 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
Index: linux-pm/drivers/pci/probe.c =================================================================== --- linux-pm.orig/drivers/pci/probe.c +++ linux-pm/drivers/pci/probe.c @@ -1208,18 +1208,6 @@ static void pci_release_capabilities(str 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 pc */ 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); Index: linux-pm/drivers/pci/remove.c =================================================================== --- linux-pm.orig/drivers/pci/remove.c +++ linux-pm/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_d 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); }