Re: 3.9.0-rc1: kexec not working: root disk does not show up
From: Konstantin Khlebnikov
Date: Thu Mar 14 2013 - 10:46:13 EST
Vivek Goyal wrote:
On Wed, Mar 13, 2013 at 06:53:16PM +0400, Konstantin Khlebnikov wrote:
[..]
PCI: Don't try to disable Bus Master on disconnected PCI devices
From: Konstantin Khlebnikov<khlebnikov@xxxxxxxxxx>
This is fix for commit 7897e6022761ace7377f0f784fca059da55f5d71 from v3.9-rc1
("PCI: Disable Bus Master unconditionally in pci_device_shutdown()")
in turn that was fix for b566a22c23327f18ce941ffad0ca907e50a53d41 from v3.5-rc1
("PCI: disable Bus Master on PCI device shutdown")
Unfortunately fixing one bug uncovers another: after ->shutdown() device can be
already disconnected from the bus and configuration space in no longer available
Link: https://lkml.org/lkml/2013/3/12/529
Signed-off-by: Konstantin Khlebnikov<khlebnikov@xxxxxxxxxx>
Reported-by: Vivek Goyal<vgoyal@xxxxxxxxxx>
Cc: Bjorn Helgaas<bhelgaas@xxxxxxxxxx>
Cc: Rafael J. Wysocki<rafael.j.wysocki@xxxxxxxxx>
---
drivers/pci/pci-driver.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 1fa1e48..79277fb 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -390,9 +390,10 @@ static void pci_device_shutdown(struct device *dev)
/*
* Turn off Bus Master bit on the device to tell it to not
- * continue to do DMA
+ * continue to do DMA. Don't touch devices in D3cold or unknown states.
*/
- pci_clear_master(pci_dev);
+ if (pci_dev->current_state<= PCI_D3hot)
+ pci_clear_master(pci_dev);
}
#ifdef CONFIG_PM
Hi,
Above patch fixed the issue on my box. Now I can kexec. Thanks.
Vivek
Ok, thanks for testing.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/