On Sunday 29 March 2009, Jeff Kirsher wrote:

On Sat, Mar 28, 2009 at 2:27 PM, Rafael J. Wysocki [off-list ref] wrote:

quoted

On Tuesday 24 March 2009, Yinghai Lu wrote:

quoted

Rafael J. Wysocki wrote:

quoted

On Thursday 12 March 2009, Yinghai Lu wrote:

quoted

Rafael J. Wysocki wrote:

quoted

On Sunday 08 March 2009, Rafael J. Wysocki wrote:

quoted

On Sunday 08 March 2009, Yinghai Lu wrote:

quoted

Rafael J. Wysocki wrote:

quoted

On Saturday 07 March 2009, Yinghai Lu wrote:

quoted

On Fri, Mar 6, 2009 at 11:18 PM, Jesse Brandeburg
[off-list ref] wrote:

quoted

On Fri, Mar 6, 2009 at 8:33 PM, Yinghai Lu [off-list ref] wrote:

quoted

Impact: could probe igb

Found one system with 82575EB, in the kernel that is kexeced, probe igb
failed with -2.

it looks like the same behavior happened on forcedeth.

try to check system_state to make sure if put it on D3

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 drivers/net/igb/igb_main.c |   19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

I see the point of the patch, but I know for a fact that ixgbe when
enabled for MSI-X also doesn't work with kexec.

so my questions are:
are you going to change every driver?

i tend to only change driver that i have related HW.

quoted

why can't this be fixed in core kernel code instead?

will check it.

quoted

Shouldn't pci_enable_device take it out of D3?
Or maybe it should be taken out of D3 immediately if someone tries to
ioremap any of the BARx registers?

looks like second kernel can not detect the state any more.

In fact pci_enable_device() calls pci_set_power_state(dev, PCI_D0) as the first
thing.  The question is why it doesn't work as expected.

not sure... please check the version for forcedeth that you made.

commit 3cb5599a84c557c0dd9a19feb63a3788268cf249
Author: Rafael J. Wysocki [off-list ref]
Date:   Fri Sep 5 14:00:19 2008 -0700

    forcedeth: fix kexec regression

    Fix regression tracked as http://bugzilla.kernel.org/show_bug.cgi?id=11361
    and caused by commit f735a2a1a4f2a0f5cd823ce323e82675990469e2 ("[netdrvr]
    forcedeth: setup wake-on-lan before shutting down") that makes network
    adapters integrated into the NVidia MCP55 chipsets fail to work in kexeced
    kernels.  The problem appears to be that if the adapter is put into D3_hot
    during ->shutdown(), it cannot be brought back into D0 after kexec (ref.
    http://marc.info/?l=linux-kernel&m=121900062814967&w=4).  Therefore, only
    put forcedeth into D3 during ->shutdown() if the system is to be powered
    off.

Thanks, I remember now.

In which case you need to rework igb_shutdown() rather than igb_suspend().

Something like the patch below, perhaps (totally untested).

it works, David, can you picked it up

Still, Yinghai, can you please also test the patch below?  It fixes all
shortcomings in the driver's suspend and shutdown methods I was talking about
in one of the previous messages.  If it works, IMO it will be a preferable fix
(in particular, it would be good to check if WoL still works with it,
but I don't have the hardware).

Thanks,
Rafael

---
From: Rafael J. Wysocki <redacted>
Subject: net/igb: Fix kexec with igb (rev. 3)
Impact: Fix

Yinghai Lu found one system with 82575EB where, in the kernel that is
kexeced, probe igb failed with -2, the reason being that the adapter
could not be brought back from D3 by the kexec kernel, most probably
due to quirky hardware (it looks like the same behavior happened on
forcedeth).

Prevent igb from putting the adapter into D3 during shutdown except
when we going to power off the system.  For this purpose, seperate
igb_shutdown() from igb_suspend() and use the appropriate PCI PM
callbacks in both of them.

Signed-off-by: Rafael J. Wysocki <redacted>
Reported-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/net/igb/igb_main.c |   42 ++++++++++++++++++++++++++++++------------
 1 file changed, 30 insertions(+), 12 deletions(-)

Index: linux-2.6/drivers/net/igb/igb_main.c
===================================================================

--- linux-2.6.orig/drivers/net/igb/igb_main.c
+++ linux-2.6/drivers/net/igb/igb_main.c

@@ -4277,7 +4277,7 @@ int igb_set_spd_dplx(struct igb_adapter
 }


-static int igb_suspend(struct pci_dev *pdev, pm_message_t state)
+static int __igb_shutdown(struct pci_dev *pdev, bool *enable_wake)
 {
    struct net_device *netdev = pci_get_drvdata(pdev);
    struct igb_adapter *adapter = netdev_priv(netdev);

@@ -4336,15 +4336,9 @@ static int igb_suspend(struct pci_dev *p
            wr32(E1000_WUFC, 0);
    }

-   /* make sure adapter isn't asleep if manageability/wol is enabled */
-   if (wufc || adapter->en_mng_pt) {
-           pci_enable_wake(pdev, PCI_D3hot, 1);
-           pci_enable_wake(pdev, PCI_D3cold, 1);
-   } else {
+   *enable_wake = wufc || adapter->en_mng_pt;
+   if (!*enable_wake)
            igb_shutdown_fiber_serdes_link_82575(hw);
-           pci_enable_wake(pdev, PCI_D3hot, 0);
-           pci_enable_wake(pdev, PCI_D3cold, 0);
-   }

    /* Release control of h/w to f/w.  If f/w is AMT enabled, this
     * would have already happened in close and is redundant. */

@@ -4352,12 +4346,29 @@ static int igb_suspend(struct pci_dev *p

    pci_disable_device(pdev);

-   pci_set_power_state(pdev, pci_choose_state(pdev, state));
-
    return 0;
 }

 #ifdef CONFIG_PM
+static int igb_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+   int retval;
+   bool wake;
+
+   retval = __igb_shutdown(pdev, &wake);
+   if (retval)
+           return retval;
+
+   if (wake) {
+           pci_prepare_to_sleep(pdev);
+   } else {
+           pci_wake_from_d3(pdev, false);
+           pci_set_power_state(pdev, PCI_D3hot);
+   }
+
+   return 0;
+}
+
 static int igb_resume(struct pci_dev *pdev)
 {
    struct net_device *netdev = pci_get_drvdata(pdev);

@@ -4412,7 +4423,14 @@ static int igb_resume(struct pci_dev *pd

 static void igb_shutdown(struct pci_dev *pdev)
 {
-   igb_suspend(pdev, PMSG_SUSPEND);
+   bool wake;
+
+   __igb_shutdown(pdev, &wake);
+
+   if (system_state == SYSTEM_POWER_OFF) {
+           pci_wake_from_d3(pdev, wake);
+           pci_set_power_state(pdev, PCI_D3hot);
+   }
 }

 #ifdef CONFIG_NET_POLL_CONTROLLER

it works too.

Great, thanks for testing.

Jeff, Jesse, is the patch fine with you?

Rafael

Let me talk with Jesse on Monday about it.  I know that Jesse's
concern's were that there were more than one driver afflicted with the
same or similar issue and that it made more sense to fix this in the
core for all drivers.  For instance ixgbe, IIRC, but because Yinghai
did not have any other hardware, it was unclear if this was an issue
on other drivers.

I think it was, at least theoretically.  We should generally avoid powering
off things on shutdown when it's not really necessary.  Also, the use of
pci_enable_wake() in these drivers is not really correct.

And in fact this is why I'm asking, because I have analogouns patches for some
other drivers in the works too.  If you are fine with the approach, I'll post
the whole series.

After discussing this with Jesse, one of us will respond.  I will
apply this patch to my tree anyway and if we are alright with the
patch, I will push it out with my other patches to Dave.

Thanks!

Best,
Rafael