From: Simon Horman
Sent: 31 July 2024 09:45
On Tue, Jul 30, 2024 at 08:31:33AM +0200, Herve Codina wrote:
Received frame from QMC contains the CRC. Upper layers don't need this CRC and tcpdump mentioned trailing junk data due to this CRC presence.
As some other HDLC driver, simply discard this CRC.
It might be nice to specifically site an example. But yes, I see this pattern in hdlc_rx_done().
Pretty much the only reason you'd want the received CRC is to do error recovery assuming a single short error burst. Not that I've ever seen a driver contain the required code. 'Back of envelope' calculation: 32bit crc, 2kbyte frame, so 18bits of crc per data bit, sqrt for 'birthday paradox' - I bet you can recover 8-bit error bursts.
David
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