From 48f67f54a53bb68619a63c3f38cf7f502ed74b1d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 22 Jan 2009 23:38:31 +0100 Subject: [PATCH] PCI PM: Power up devices before restoring their state Devices that have MSI-X enabled before suspend to RAM or hibernation and that are in a low power state during resume will not be handled correctly by pci_restore_standard_config(). Namely, it first calls pci_restore_state() which calls pci_restore_msi_state(), which in turn executes __pci_restore_msix_state() that accesses the device's memory space to restore the contents of the MSI-X table. However, if the device is in a low power state at this point, it's memory space is not accessible. The easiest way to fix this potential problem is to make pci_restore_standard_config() call pci_restore_state() after it has put the device into the full power state, D0. Fortunately, all of this is done with interrupts off, so the change of ordering should not cause any trouble. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 17bd932..f0aa3d5 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1393,12 +1393,11 @@ int pci_restore_standard_config(struct pci_dev *dev) pci_power_t prev_state; int error; - pci_restore_state(dev); pci_update_current_state(dev, PCI_D0); prev_state = dev->current_state; if (prev_state == PCI_D0) - return 0; + goto Restore; error = pci_raw_set_power_state(dev, PCI_D0, false); if (error) @@ -1421,7 +1420,8 @@ int pci_restore_standard_config(struct pci_dev *dev) dev->current_state = PCI_D0; - return 0; + Restore: + return pci_restore_state(dev); } /** -- 1.8.2.3