Re: [PATCH] e1000e: Relax condition to trigger reset for ME workaround

From: Punit Agrawal
Date: Thu May 21 2020 - 23:21:20 EST


Hi Aaron,

"Brown, Aaron F" <aaron.f.brown@xxxxxxxxx> writes:

>> From: netdev-owner@xxxxxxxxxxxxxxx <netdev-owner@xxxxxxxxxxxxxxx> On
>> Behalf Of Punit Agrawal
>> Sent: Thursday, May 14, 2020 9:31 PM
>> To: Kirsher, Jeffrey T <jeffrey.t.kirsher@xxxxxxxxx>
>> Cc: daniel.sangorrin@xxxxxxxxxxxxx; Punit Agrawal
>> <punit1.agrawal@xxxxxxxxxxxxx>; Alexander Duyck
>> <alexander.h.duyck@xxxxxxxxxxxxxxx>; David S. Miller <davem@xxxxxxxxxxxxx>;
>> intel-wired-lan@xxxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-
>> kernel@xxxxxxxxxxxxxxx
>> Subject: [PATCH] e1000e: Relax condition to trigger reset for ME workaround
>>
>> It's an error if the value of the RX/TX tail descriptor does not match
>> what was written. The error condition is true regardless the duration
>> of the interference from ME. But the driver only performs the reset if
>> E1000_ICH_FWSM_PCIM2PCI_COUNT (2000) iterations of 50us delay have
>> transpired. The extra condition can lead to inconsistency between the
>> state of hardware as expected by the driver.
>>
>> Fix this by dropping the check for number of delay iterations.
>>
>> While at it, also make __ew32_prepare() static as it's not used
>> anywhere else.
>>
>> Signed-off-by: Punit Agrawal <punit1.agrawal@xxxxxxxxxxxxx>
>> Reviewed-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx>
>> Cc: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
>> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
>> Cc: intel-wired-lan@xxxxxxxxxxxxxxxx
>> Cc: netdev@xxxxxxxxxxxxxxx
>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>> ---
>> Hi Jeff,
>>
>> If there are no further comments please consider merging the patch.
>>
>> Also, should it be marked for backport to stable?
>>
>> Thanks,
>> Punit
>>
>> RFC[0] -> v1:
>> * Dropped return value for __ew32_prepare() as it's not used
>> * Made __ew32_prepare() static
>> * Added tags
>>
>> [0] https://lkml.org/lkml/2020/5/12/20
>>
>> drivers/net/ethernet/intel/e1000e/e1000.h | 1 -
>> drivers/net/ethernet/intel/e1000e/netdev.c | 12 +++++-------
>> 2 files changed, 5 insertions(+), 8 deletions(-)
>>
> Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>

Thanks for taking the patch for a spin.

Jeff, let me know if you're okay to apply the tag or want me to send a
new version.

Thanks,
Punit