[2.6.18-rc2][e1000][swsusp] - Regression - Suspend to disk and resume breaks e1000

[2.6.18-rc2][e1000][swsusp] - Regression - Suspend to disk and resume breaks e1000

[Shawn Starr]

Hardware

IBM ThinkPad T42
E1000 card info: 

02:01.0 Ethernet controller: Intel Corporation 82540EP Gigabit Ethernet 
Controller (Mobile) (rev 03)
        Subsystem: IBM PRO/1000 MT Mobile Connection
        Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 9
        Memory at c0220000 (32-bit, non-prefetchable) [size=128K]
        Memory at c0200000 (32-bit, non-prefetchable) [size=64K]
        I/O ports at 8000 [size=64]
        [virtual] Expansion ROM at ec000000 [disabled] [size=64K]
        Capabilities: [dc] Power Management version 2

Steps to reproduce:

1) Suspend to disk normally
2) Resume from disk, the e1000 will show garbage for network statistics.

<snip>
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:83 errors:4294967254 dropped:4294967289 overruns:0 
frame:4294967268
          TX packets:76 errors:4294967282 dropped:0 overruns:0 
carrier:4294967275
          collisions:4294967289 txqueuelen:100
          RX bytes:50728 (49.5 KiB)  TX bytes:10138 (9.9 KiB)
          Base address:0x8000 Memory:c0220000-c0240000

Did something change in the driver that forgot to save the registers / not 
register back upon resumption from disk? I can't tell from the code how the 
driver knows its been brought down to S3 or S4 states.
 
A workaround is to then suspend to memory and resume, the e1000 will work 
again. This is repeatable each time.

Not sure if anyone else noticed this.

Thanks, 

Shawn.

Re: [2.6.18-rc2][e1000][swsusp] - Regression - Suspend to disk and resume breaks e1000

[Auke Kok]

Shawn Starr wrote:
> Hardware
> 
> IBM ThinkPad T42
> E1000 card info: 
> 
> 02:01.0 Ethernet controller: Intel Corporation 82540EP Gigabit Ethernet 
> Controller (Mobile) (rev 03)
>         Subsystem: IBM PRO/1000 MT Mobile Connection
>         Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 9
>         Memory at c0220000 (32-bit, non-prefetchable) [size=128K]
>         Memory at c0200000 (32-bit, non-prefetchable) [size=64K]
>         I/O ports at 8000 [size=64]
>         [virtual] Expansion ROM at ec000000 [disabled] [size=64K]
>         Capabilities: [dc] Power Management version 2
> 
> Steps to reproduce:
> 
> 1) Suspend to disk normally
> 2) Resume from disk, the e1000 will show garbage for network statistics.
> 
> <snip>
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:83 errors:4294967254 dropped:4294967289 overruns:0 
> frame:4294967268
>           TX packets:76 errors:4294967282 dropped:0 overruns:0 
> carrier:4294967275
>           collisions:4294967289 txqueuelen:100
>           RX bytes:50728 (49.5 KiB)  TX bytes:10138 (9.9 KiB)
>           Base address:0x8000 Memory:c0220000-c0240000
> 
> Did something change in the driver that forgot to save the registers / not 
> register back upon resumption from disk? I can't tell from the code how the 
> driver knows its been brought down to S3 or S4 states.
>  
> A workaround is to then suspend to memory and resume, the e1000 will work 
> again. This is repeatable each time.
> 
> Not sure if anyone else noticed this.

[adding netdev to the cc]


unfortunately I didn't.

e1000 has a special e1000_pci_save_state/e1000_pci_restore_state set of 
routines that save and restore the configuration space. the fact that it works 
for suspend to memory to me suggests that there is nothing wrong with that.

I'm surprised that the t42 comes with a PCI/PCI-X e1000, which changes the 
need for this special routine, and the routine does the exact same thing as 
pci_save_state in your case. These special routines are made to handle PCI-E 
cards properly.

Also there are no config_pm changes related to this in 2.6.18-rc2. Most of 
this code has been in the kernel for a few major releases afaik. This code 
worked fine before, so I don't rule out any suspend-related issues. You should 
certainly compare with 2.6.18-rc1 and make sure it was a regression, perhaps 
even bisect the e1000-related changes if you have the time, which is about 22 
patches or so.

I'll see if I can find out some more once I get back to work.

Auke

Re: [2.6.18-rc2][e1000][swsusp] - Regression - Suspend to disk and resume breaks e1000

[Shawn Starr]

On Sunday 16 July 2006 12:33, Auke Kok wrote:
> [adding netdev to the cc]
>
>
> unfortunately I didn't.
>
> e1000 has a special e1000_pci_save_state/e1000_pci_restore_state set of
> routines that save and restore the configuration space. the fact that it
> works for suspend to memory to me suggests that there is nothing wrong with
> that.
>
> I'm surprised that the t42 comes with a PCI/PCI-X e1000, which changes the
> need for this special routine, and the routine does the exact same thing as
> pci_save_state in your case. These special routines are made to handle
> PCI-E cards properly.
>
> Also there are no config_pm changes related to this in 2.6.18-rc2. Most of
> this code has been in the kernel for a few major releases afaik. This code
> worked fine before, so I don't rule out any suspend-related issues. You
> should certainly compare with 2.6.18-rc1 and make sure it was a regression,
> perhaps even bisect the e1000-related changes if you have the time, which
> is about 22 patches or so.
>
> I'll see if I can find out some more once I get back to work.
>
> Auke

The previous kernel I was using was 2.6.17 vanilla, so between this and -git 
snapshots I'll have to see where that changed.

Thanks ,
Shawn.

Re: [2.6.18-rc2][e1000][swsusp] - Regression - Suspend to disk and resume breaks e1000 - RESOLVED Bug #6867

[Shawn Starr]

On Sunday 16 July 2006 12:33 pm, Auke Kok wrote:
> [adding netdev to the cc]
>
> unfortunately I didn't.
>
> e1000 has a special e1000_pci_save_state/e1000_pci_restore_state set of
> routines that save and restore the configuration space. the fact that it
> works for suspend to memory to me suggests that there is nothing wrong with
> that.
>
> I'm surprised that the t42 comes with a PCI/PCI-X e1000, which changes the
> need for this special routine, and the routine does the exact same thing as
> pci_save_state in your case. These special routines are made to handle
> PCI-E cards properly.
>
> Also there are no config_pm changes related to this in 2.6.18-rc2. Most of
> this code has been in the kernel for a few major releases afaik. This code
> worked fine before, so I don't rule out any suspend-related issues. You
> should certainly compare with 2.6.18-rc1 and make sure it was a regression,
> perhaps even bisect the e1000-related changes if you have the time, which
> is about 22 patches or so.
>
> I'll see if I can find out some more once I get back to work.
>
> Auke

Hi Auke,

It appears 2.6.18-rc3 this does not occur anymore. I suspended to disk/ram and 
the interface pci registers were restored. Bugzilla #6867

Thanks, 

Shawn.

Re: [2.6.18-rc2][e1000][swsusp] - Regression - Suspend to disk and resume breaks e1000 - RESOLVED Bug #6867

[Auke Kok]

Shawn Starr wrote:
> On Sunday 16 July 2006 12:33 pm, Auke Kok wrote:
>> [adding netdev to the cc]
>>
>> unfortunately I didn't.
>>
>> e1000 has a special e1000_pci_save_state/e1000_pci_restore_state set of
>> routines that save and restore the configuration space. the fact that it
>> works for suspend to memory to me suggests that there is nothing wrong with
>> that.

> Hi Auke,
> 
> It appears 2.6.18-rc3 this does not occur anymore. I suspended to disk/ram and 
> the interface pci registers were restored. Bugzilla #6867

I would not be surprised if all the suspend issues in 2.6.18rcX were not 
involved in this somehow... thanks for reporting back in.

Auke