Re: [Intel-wired-lan] [PATCH] e1000e: disregard NVM checksum on tgp when valid checksum mask is not set

From: Lifshits, Vitaly
Date: Thu Apr 24 2025 - 13:01:13 EST


On 4/24/2025 7:24 PM, Simon Horman wrote:
On Tue, Apr 22, 2025 at 09:43:01AM +0200, Jacek Kowalski wrote:
Some Dell Tiger Lake systems have incorrect NVM checksum. These also
have a bitmask that indicates correct checksum set to "invalid".

Because it is impossible to determine whether the NVM write would finish
correctly or hang (see https://bugzilla.kernel.org/show_bug.cgi?id=213667)
it makes sense to skip the validation completely under these conditions.
It is not completely accurate. All the NVMs starting from Tiger Lake are locked for writes, so NVM writes will always result in a failure.

Perhaps something like this:
"
All the NVMs starting from Tiger Lake are locked for writes, so NVM writes will always result in a failure. Since tgp devices were the first to have this lock, some manufacturers didn't create a correct image resulting in this wrong checksum issue. Therefore, it makes these devices as a transition period, skip updating the checksum if the bit wasn't set.
"

Signed-off-by: Jacek Kowalski <Jacek@xxxxxxxxxxx>
Fixes: 4051f68318ca9 ("e1000e: Do not take care about recovery NVM checksum")
I think that while the commit cited above relates to this problem,
this bug actually dates back to the patch I'm citing immediately below.
And I think we should cite that commit here. IOW, I'm suggesting:

Fixes: fb776f5d57ee ("e1000e: Add support for Tiger Lake")

Cc: stable@xxxxxxxxxxxxxxx
That not withstanding, based on the commit message,
and the use of e1000_pch_tgp in another Tiger Lake fix [1],
I think this patch looks good.

Reviewed-by: Simon Horman <horms@xxxxxxxxxx>

[1] commit ffd24fa2fcc7 ("e1000e: Correct NVM checksum verification flow")