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rtwn: enable FCS in the recive config to work around truncated frames
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Authored by adrian on Wed, Nov 27, 1:04 AM.
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Details

Summary

I noticed that on RTL8812AU/RTL8821AU receiving VHT frames that
I'd occasionally see frames missing the last 4 bytes. I can
easily reproduce it with a ping sweep and fast (10ms) between frames.

There's also a report of an earlier NIC (RTL8188EU) doing the same
thing with HT frames but not with OFDM (11g) frames.

After a bunch of poking, it turns out a driver where things DID work
properly for the other report kept FCS enabled, and trimmed it from
the frame before pushing it up to the network layer.

I did the same and it also worked fine.

The other solution was to disable PHYSTATUS notifications, but then
we'd get no per packet RX notifications (RX rate, RSSI, etc.)

Locally tested:

  • RTL8192EU, STA mode (HT)
  • RTL8812AU, STA mode (HT, VHT)
  • RTL8821AU, STA mode (HT, VHT)

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add url

Where?

oh it's when I do commit update to add the differential revision to the git commit message

oh it's when I do commit update to add the differential revision to the git commit message

Ah, yes - I'm not aware of an automatic way to update that in Phab, but you can edit the message manually to match what you propose.

oh it's when I do commit update to add the differential revision to the git commit message

Ah, yes - I'm not aware of an automatic way to update that in Phab, but you can edit the message manually to match what you propose.

Yea, we need both a way to tag reviews with a phab D# and a way to sync the phab with the commit message. Should be on srcmgr wish list.

Likely fine. But likely also needs testing with a large variety of devices/firmware.

I've tested this on every supported rtwn NIC i can find. I think it should be fine.

This revision was not accepted when it landed; it landed in state Needs Review.Thu, Dec 5, 7:31 AM
This revision was automatically updated to reflect the committed changes.