Some time ago we had a few reports of AR2413 cards being unable to encrypt packets of specific lengths. >From https://bugs.launchpad.net/ubuntu/+source/linux/+bug/568090, user Musaraigne did some further investigation/debuging on this: "The cause of the high and unpredictable latencies is that packets are dropped depending on their size. According to my tests, packet sizes of the form size = 128*k + 81 + m or size = 128*k + 105 + m for any k>=2 and 0<=m<=7 are dropped randomly in 90-95% of the cases. Conversely, all other packet sizes work fine. You can see for yourself if this is true on your system: ping -M do -s 596 www.google.com should result in 90% packet loss (because 624 = 128*4 + 105 + 7; the 28 byte difference comes from network headers added by ping) while ping -M do -s 597 www.google.com should result in negligible packet loss." So far I couldn't reproduce this bug with my AR2413 and now after e few user reports I'm almost sure that it's only present on cards created by Askey. I verified it again recently based on a bug report from an OpenSUSE user here... https://bugzilla.novell.com/show_bug.cgi?id=731576 What seems weird is that some users reported that MadWiFi worked fine on these cards (I have no idea what happens on their windows driver, maybe they disable hw crypto) ! Since for hw crypto we use code from the common ath module (and I think this is the same with HAL) I don't see how that can happen. Anyway my question is how to handle this: a) Just disable hw crypto for all AR2413 cards made by Askey b) If we handle such card do some padding based on Musaraigne's findings I'd like to go with b but I don't know how to do it correctly without corrupting anything. Any ideas ? -- GPG ID: 0xEE878588 As you read this post global entropy rises. Have Fun ;-) Nick -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
