Bug 6484

Summary:	dropouts with user mode PPPoE
Product:	Networking	Reporter:	Nuri Jawad (lkml)
Component:	Other	Assignee:	Arnaldo Carvalho de Melo (acme)
Status:	CLOSED PATCH_ALREADY_AVAILABLE
Severity:	normal
Priority:	P2
Hardware:	i386
OS:	Linux
Kernel Version:	2.6.16 and above	Subsystem:
Regression:	---	Bisected commit-id:

Description Nuri Jawad 2006-05-02 13:28:01 UTC

Distribution: Debian
Hardware Environment: P4 Northwood, 2 GB, i875, e1000 CSA
Software Environment: pppd, rp-pppoe

Problem Description:
ADSL connection through PPPoE occasionally stalls for 30 to 50 seconds,
especially under load. During these dropouts, packets are received but none that
are supposed to be sent appear on ppp0. Ethernet interface continues to work,
telnet session to modem does not stall.

Exhibition of the bug is not affected by:
SMP or uniprocessor kernel, Hyper Threading disabled or enabled, pppd version
(tested with 2.4.2 and 2.4.4b1), rp-pppoe version (tested 3.5 & 3.8).
CPU load is probably not a factor either.

Dropouts seem to appear more frequently when the connection is under load (large
Bittorrent swarms are a good test). They can appear as soon as a few minutes
after start but it also took more than 5 hours once. Most of the time, they will
appear every half to one hour.

Problem does not occur with 2.6.15.7 or earlier. Second system with AMD64
SanDiego & NForce4 is not affected, will try to match configuration as closely
as possible and retest.
Kernel mode PPPoE using the rp-pppoe plugin does also not exhibit the bug.

2.6.17-rc3 .config:
http://jawad.org/.config

Comment 1 Nuri Jawad 2006-09-11 21:17:15 UTC

Problem does no longer occur in 2.6.17.7. I have no information about the
version where the fix might have been introduced.