]> git.karo-electronics.de Git - linux-beck.git/commit
PCI: Assign resources before drivers claim devices (pci_scan_root_bus())
authorYijing Wang <wangyijing@huawei.com>
Mon, 16 Mar 2015 03:18:56 +0000 (11:18 +0800)
committerBjorn Helgaas <bhelgaas@google.com>
Thu, 19 Mar 2015 15:17:13 +0000 (10:17 -0500)
commitb97ea289cf6aff8d4cbcefe2b707bb9b00a73c73
treeefa328fedf08e394912322783660d27c33257610
parentc90570d9511d42421c85709b46bffd366185d835
PCI: Assign resources before drivers claim devices (pci_scan_root_bus())

Previously, pci_scan_root_bus() created a root PCI bus, enumerated the
devices on it, and called pci_bus_add_devices(), which made the devices
available for drivers to claim them.

Most callers assigned resources to devices after pci_scan_root_bus()
returns, which may be after drivers have claimed the devices.  This is
incorrect; the PCI core should not change device resources while a driver
is managing the device.

Remove pci_bus_add_devices() from pci_scan_root_bus() and do it after any
resource assignment in the callers.

Note that ARM's pci_common_init_dev() already called pci_bus_add_devices()
after pci_scan_root_bus(), so we only need to remove the first call:

  pci_common_init_dev
    pcibios_init_hw
      pci_scan_root_bus
        pci_bus_add_devices        # first call
    pci_bus_assign_resources
    pci_bus_add_devices            # second call

[bhelgaas: changelog, drop "root_bus" var in alpha common_init_pci(),
return failure earlier in mn10300, add "return" in x86 pcibios_scan_root(),
return early if xtensa platform_pcibios_fixup() fails]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: Matt Turner <mattst88@gmail.com>
CC: David Howells <dhowells@redhat.com>
CC: Tony Luck <tony.luck@intel.com>
CC: Michal Simek <monstr@monstr.eu>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: Chris Metcalf <cmetcalf@ezchip.com>
CC: Chris Zankel <chris@zankel.net>
CC: Max Filippov <jcmvbkbc@gmail.com>
CC: Thomas Gleixner <tglx@linutronix.de>
15 files changed:
arch/alpha/kernel/pci.c
arch/frv/mb93090-mb00/pci-vdk.c
arch/ia64/sn/kernel/io_init.c
arch/microblaze/pci/pci-common.c
arch/mips/pci/pci.c
arch/mn10300/unit-asb2305/pci.c
arch/s390/pci/pci.c
arch/sh/drivers/pci/pci.c
arch/sparc/kernel/leon_pci.c
arch/tile/kernel/pci.c
arch/tile/kernel/pci_gx.c
arch/x86/pci/common.c
arch/xtensa/kernel/pci.c
drivers/pci/host/pci-versatile.c
drivers/pci/probe.c