TBF Seems broken in recent X86-64 kernels

It appears that the breakage occurred somewhere between 2.6.26 and
2.6.32. I've tried this on recent X86 Fedora, OpenSuSE and Debian
releases and the results are similar. In all cases, X86 works as expected.

Here's a test on 2.6.26:

sami:~# uname -r
2.6.26-2-vserver-amd64
sami:~# scp shorewall-docs-xml-4.4.17.tgz gateway:
shorewall-docs-xml-4.4.17.tgz     100% 6306KB   6.2MB/s   00:00

sami:~# tc qdisc add dev eth4 root handle 1: tbf rate 6300kbit \
                               burst 100kb latency 200ms mpu 64

sami:~# scp shorewall-docs-xml-4.4.17.tgz gateway:
shorewall-docs-xml-4.4.17.tgz     100% 6306KB   1.0MB/s   00:06

sami:~# tc -s qdisc ls dev eth4; tc -s class ls dev eth4
qdisc tbf 1: root rate 6300Kbit burst 100Kb lat 200.0ms
 Sent 6919034 bytes 6366 pkt (dropped 4, overlimits 8825 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
class tbf 1:1 parent 1:
sami:~#

This test is from 2.6.32:

#gateway:~# uname -r
2.6.32-5-vserver-amd64

root@gateway:~# scp shorewall-docs-xml-4.4.17.tgz sami:
shorewall-docs-xml-4.4.17.tgz     100% 6306KB   6.2MB/s   00:00

root@gateway:~# scp shorewall-docs-xml-4.4.17.tgz sami:
shorewall-docs-xml-4.4.17.tgz        100% 6306KB   6.2MB/s   00:00
root@gateway:~# tc qdisc add dev eth4 root handle 1: tbf rate \
                         6300kbit burst 100kb latency 200ms mpu 64
root@gateway:~# scp shorewall-docs-xml-4.4.17.tgz sami:
shorewall-docs-xml-4.4.17.tgz         38% 2448KB  30.8KB/s - stalled -
shorewall-docs-xml-4.4.17.tgz         38% 2448KB  27.7KB/s - stalled -

At this point I killed scp.

root@gateway:~# tc -s qdisc ls dev eth1; tc -s class ls dev eth1
qdisc tbf 1: root refcnt 6 rate 6300Kbit burst 100Kb lat 200.0ms
 Sent 1097211 bytes 1347 pkt (dropped 285, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
class tbf 1:1 parent 1:

root@gateway:~#

-Tom
-- 
Tom Eastep        \ When I die, I want to go like my Grandfather who
Shoreline,         \ died peacefully in his sleep. Not screaming like
Washington, USA     \ all of the passengers in his car
http://shorewall.net \________________________________________________

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