[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [PATCH for-7.2] rtl8139: honor large send MSS value

From: Tobias Fiebig
Subject: RE: [PATCH for-7.2] rtl8139: honor large send MSS value
Date: Wed, 16 Nov 2022 03:58:54 +0100

I just tested around with the patch;
Good news: Certainly my builds are being executed. Also, if I patch the old 
code to have a MAX_MTU <= the max MTU on my path, throughput is ok.

Bad news: Something is wrong with getting the MSS in the patch you shared. When 
enabling DPRINT, values are off (sent MSS vs. printed MSS):
600 2060
800 2308
1000 2316
1023 2307
1200 3076
1400 3340 (most likely clamped to 1320)

Fiddling around a bit more, I found txdw0 printed earlier in the stack as hex 
(sent MSS, txdw0):
769 900502f5
1000 900503dc
1280 900504f4
1281 900504f5
1301 90050509
1317 90050519
1320 9005051c

This maps rather well to:
MSS = txdw0 - 2416246772 
MSS = txdw0 - 9004FFF4

Sadly, my C is 'non-existent' and it is kind-of 4AM, so also not in the 
brainspace to fill those gaps. But if one of you could look at the patch again, 
that would be nice. Otherwise, I should have some brainspace for this tomorrow 
night (UTC) again.

With best regards,

reply via email to

[Prev in Thread] Current Thread [Next in Thread]