tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

Nice job Aldo!

I forward this message to netdev and Cc our best tcp expert.
Any new replies should be rather "Reply All" (not bugzilla only).

Thanks,
Jarek P.

On Sat, Oct 18, 2008 at 01:20:56PM -0700, bugme-daemon@bugzilla.kernel.org wrote:
> http://bugzilla.kernel.org/show_bug.cgi?id=11721
> 
...
> ------- Comment #30 from sentiniate@tiscali.it  2008-10-18 13:20 -------
> absolutely i'm not fed up! and actually i thank you for your patience.
> 
> i set paperino as you wrote and added ifconfig eth0 mtu 1400 as well
> i set the same value of mtu in topolino as well, i hope i was not wrong doing
> so!
> 
> i attach the files you ask for, but now i can navigate with 2.6.27-rc1-git1 as
> well!
> 
> afterwards i've run some more tests and have found out that the culprit is
> tcp_sack, if using kernel 2.6.27-rc1-gt1 it is set to "1" i cannot navigate if
> to "0" i can.
> so i enclose, should it be of any help, also the tcpdump on eth0 of topolino
> when on paperino tcp_sack is set to "1".
> 
> thanks
> aldo
> 
> 
> -- 
> Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug, or are watching someone who is.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

[RESEND] I forgot to add Aldo's email before - sorry!

On Sat, Oct 18, 2008 at 11:02:52PM +0200, Jarek Poplawski wrote:
> Nice job Aldo!
> 
> I forward this message to netdev and Cc our best tcp expert.
> Any new replies should be rather "Reply All" (not bugzilla only).
> 
> Thanks,
> Jarek P.
> 
> On Sat, Oct 18, 2008 at 01:20:56PM -0700, bugme-daemon@bugzilla.kernel.org wrote:
> > http://bugzilla.kernel.org/show_bug.cgi?id=11721
> > 
> ...
> > ------- Comment #30 from sentiniate@tiscali.it  2008-10-18 13:20 -------
> > absolutely i'm not fed up! and actually i thank you for your patience.
> > 
> > i set paperino as you wrote and added ifconfig eth0 mtu 1400 as well
> > i set the same value of mtu in topolino as well, i hope i was not wrong doing
> > so!
> > 
> > i attach the files you ask for, but now i can navigate with 2.6.27-rc1-git1 as
> > well!
> > 
> > afterwards i've run some more tests and have found out that the culprit is
> > tcp_sack, if using kernel 2.6.27-rc1-gt1 it is set to "1" i cannot navigate if
> > to "0" i can.
> > so i enclose, should it be of any help, also the tcpdump on eth0 of topolino
> > when on paperino tcp_sack is set to "1".
> > 
> > thanks
> > aldo
> > 
> > 
> > -- 
> > Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email
> > ------- You are receiving this mail because: -------
> > You are on the CC list for the bug, or are watching someone who is.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

>> On Sat, Oct 18, 2008 at 01:20:56PM -0700, bugme-daemon@bugzilla.kernel.org wrote:
>>> http://bugzilla.kernel.org/show_bug.cgi?id=11721
...
>>> ------- Comment #30 from sentiniate@tiscali.it  2008-10-18 13:20 -------
...
>>> afterwards i've run some more tests and have found out that the culprit is
>>> tcp_sack, if using kernel 2.6.27-rc1-gt1 it is set to "1" i cannot navigate if
>>> to "0" i can.
...

Aldo, for curiosity, could you also try if this change only
(instead of tcp_sack etc.) can't do similar effect?:

echo 0 > /proc/sys/net/ipv4/tcp_timestamps

Thanks,
Jarek P.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Ilpo Järvinen]

On Sat, 18 Oct 2008, Jarek Poplawski wrote:

> [RESEND] I forgot to add Aldo's email before - sorry!
> 
> On Sat, Oct 18, 2008 at 11:02:52PM +0200, Jarek Poplawski wrote:
> > Nice job Aldo!
> > 
> > I forward this message to netdev and Cc our best tcp expert.
> > Any new replies should be rather "Reply All" (not bugzilla only).
> > 
> > Thanks,
> > Jarek P.
> > 
> > On Sat, Oct 18, 2008 at 01:20:56PM -0700, bugme-daemon@bugzilla.kernel.org wrote:
> > > http://bugzilla.kernel.org/show_bug.cgi?id=11721
> > > 
> > ...
> > > ------- Comment #30 from sentiniate@tiscali.it  2008-10-18 13:20 -------
> > > absolutely i'm not fed up! and actually i thank you for your patience.
> > > 
> > > i set paperino as you wrote and added ifconfig eth0 mtu 1400 as well
> > > i set the same value of mtu in topolino as well, i hope i was not wrong doing
> > > so!
> > > 
> > > i attach the files you ask for, but now i can navigate with 2.6.27-rc1-git1 as
> > > well!
> > > 
> > > afterwards i've run some more tests and have found out that the culprit is
> > > tcp_sack, if using kernel 2.6.27-rc1-gt1 it is set to "1" i cannot navigate if
> > > to "0" i can.
> > > so i enclose, should it be of any help, also the tcpdump on eth0 of topolino
> > > when on paperino tcp_sack is set to "1".

So this ended up into tcp domain after all (I took earlier a brief 
anyway and found out that there are not that many changes 2.6.26..2.6.27 
-- net/ipv4/tcp*.c include/net/tcp.h)...

I compared your packet against a good one from elsewhere.. I couldn't 
compare your latest dumps fully because attachments 18366 and 18367 are 
with different TCP options (you forgot zeros to sysctls in them?)... 
Anyway, only thing that seemed to be different to that case from elsewhere 
were those extra bytes in the beginning (some below ip protocol that 
gets captured by tcpdump?) which are equal in both working and broken case 
of yours and the different ordering of the tcp options as noted by Jarek 
earlier. I tried to go through the fields one by one but nothing seemed to 
be wrong...

...Might be something crazy in the way that is too picky on tcp option 
ordering which wouldn't surprise me that much... :-) Please try if
the patch below does any difference (on paperino is enough, the gw seems 
innocent here).

If that didn't help, can you please restore the sysctls to 1 and redo
2.6.26.6 dump (like in attachment 18366) so that I get a fully comparable 
sample.

-- 
 i.


diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 990a584..850a4e9 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -376,6 +376,12 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
 		*md5_hash = NULL;
 	}
 
+	if (unlikely(opts->mss)) {
+		*ptr++ = htonl((TCPOPT_MSS << 24) |
+			       (TCPOLEN_MSS << 16) |
+			       opts->mss);
+	}
+
 	if (likely(OPTION_TS & opts->options)) {
 		if (unlikely(OPTION_SACK_ADVERTISE & opts->options)) {
 			*ptr++ = htonl((TCPOPT_SACK_PERM << 24) |
@@ -392,12 +398,6 @@ static void tcp_options_write(__be32 *ptr, struct tcp_sock *tp,
 		*ptr++ = htonl(opts->tsecr);
 	}
 
-	if (unlikely(opts->mss)) {
-		*ptr++ = htonl((TCPOPT_MSS << 24) |
-			       (TCPOLEN_MSS << 16) |
-			       opts->mss);
-	}
-
 	if (unlikely(OPTION_SACK_ADVERTISE & opts->options &&
 		     !(OPTION_TS & opts->options))) {
 		*ptr++ = htonl((TCPOPT_NOP << 24) |

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

On Mon, Oct 20, 2008 at 12:38:51PM +0300, Ilpo Järvinen wrote:
...
> ...Might be something crazy in the way that is too picky on tcp option 
> ordering which wouldn't surprise me that much... :-) Please try if
> the patch below does any difference (on paperino is enough, the gw seems 
> innocent here).

I've just thought about this too(!), and it seems that turning of
tcp_timestamps should do similar reorder. But of course, I'll try
not to disturb anymore...

Thanks,
Jarek P.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Ilpo Järvinen]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 853 bytes --]

On Mon, 20 Oct 2008, Jarek Poplawski wrote:

> On Mon, Oct 20, 2008 at 12:38:51PM +0300, Ilpo Järvinen wrote:
> ...
> > ...Might be something crazy in the way that is too picky on tcp option 
> > ordering which wouldn't surprise me that much... :-) Please try if
> > the patch below does any difference (on paperino is enough, the gw seems 
> > innocent here).
> 
> I've just thought about this too(!), and it seems that turning of
> tcp_timestamps should do similar reorder. But of course, I'll try
> not to disturb anymore...

Yeah, you should be right. No need to patch+compile+boot hassle him, 
turning timestamps should be "enough" to move mss into first slot... :-)

If that works we probably need to play around a bit to figure out what
is the actual cause (since it could involve timestamps or mss which the 
sysctl alone cannot prove).

-- 
 i.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

On Mon, Oct 20, 2008 at 08:47:37AM -0700, bugme-daemon@bugzilla.kernel.org wrote:
> http://bugzilla.kernel.org/show_bug.cgi?id=11721
...
> ------- Comment #40 from sentiniate@tiscali.it  2008-10-20 08:47 -------
> ok setting echo 0 > /proc/sys/net/ipv4/tcp_timestamps solves the problem as
> well.
> 
> anyway i'm willing to do whatever test you deem necessary if this can help you
> solve the issue, so as soon as i can i'll apply the patch provided by  Ilpo
> Järvinen and compile (do not worry i've been a linux user for the last 10
> years and up to 4 or 5 yrs ago i used to compile even three times a week!)
> 
> thanks
> aldo

Aldo, I forward this message to Ilpo and netdev, because "they" aren't
on the Cc list of this report. (With next replies try to use the mail
with their addresses.)

I think, you could test Ilpo's patch as well: this would make slightly
different test/header. (Of course, all these /proc tcp values and mtus
should be back to normal.)

Thanks,
Jarek P.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Aldo Maggi]

[-- Attachment #1: Type: text/plain, Size: 918 bytes --]

Jarek,
sorry i did not read your last msg before, so i have used the bug page
for posting.

i repeat here what i wrote there:

Ilpo,
i'm sending herewith attached the output of
tcpdump -i eth0 -nXX -c3 'dst port 80 and tcp-syn != 0' on topolino when:
1) kernel 2.6.26.6 is running on paperino and tcp_window_scaling,
tcp_timestamps, tcp_sack are set to "1"
2) kernel 2.6.26.6 is running on paperino and tcp_window_scaling,
tcp_timestamps, tcp_sack are set to "0"
3) kernel 2.6.27-rc1-git1 is running on paperino and tcp_window_scaling,
tcp_timestamps, tcp_sack are set to "1"
4) kernel 2.6.27-rc1-git1 is running on paperino and tcp_window_scaling,
tcp_timestamps, tcp_sack are set to "0"

moreover, i read more carefully what you and Jarek wrote above, please let me
know if you deem still necessary that i apply the patch you provided and
compile or if you like i compile the latest kernel or whatever.

thanks
aldo

[-- Attachment #2: tcpdump_2-6-26_tcp_0 --]
[-- Type: application/octet-stream, Size: 1217 bytes --]

21:27:18.619016 IP 192.168.254.1.60630 > 204.152.191.37.80: S 1427374161:1427374161(0) win 5840 <mss 1460>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  002c 4c04 4000 3f06 a55f c0a8 fe01 cc98  .,L.@.?.._......
	0x0020:  bf25 ecd6 0050 5514 0051 0000 0000 6002  .%...PU..Q....`.
	0x0030:  16d0 f461 0000 0204 05b4                 ...a......
21:27:18.839051 IP 192.168.254.1.60630 > 204.152.191.37.80: . ack 2813695036 win 5840
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0028 4c05 4000 3f06 a562 c0a8 fe01 cc98  .(L.@.?..b......
	0x0020:  bf25 ecd6 0050 5514 0052 a7b5 943c 5010  .%...PU..R...<P.
	0x0030:  16d0 d01c 0000                           ......
21:27:18.839293 IP 192.168.254.1.60630 > 204.152.191.37.80: P 0:240(240) ack 1 win 5840
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0118 4c06 4000 3f06 a471 c0a8 fe01 cc98  ..L.@.?..q......
	0x0020:  bf25 ecd6 0050 5514 0052 a7b5 943c 5018  .%...PU..R...<P.
	0x0030:  16d0 d5fe 0000 4745 5420 2f20 4854 5450  ......GET./.HTTP
	0x0040:  2f31 2e30 0d0a 5573 6572 2d41 6765 6e74  /1.0..User-Agent
	0x0050:  3a20 7733 6d2f 302e 352e 320d 0a41 6363  :.w3m/0.5.2..Acc

[-- Attachment #3: tcpdump_2-6-26_tcp_1 --]
[-- Type: application/octet-stream, Size: 1459 bytes --]

21:25:22.757937 IP 192.168.254.1.57412 > 204.152.191.5.80: S 3914166537:3914166537(0) win 5840 <mss 1460,sackOK,timestamp 1694512 0,nop,wscale 6>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  003c aa39 4000 3f06 473a c0a8 fe01 cc98  .<.9@.?.G:......
	0x0020:  bf05 e044 0050 e94d 7109 0000 0000 a002  ...D.P.Mq.......
	0x0030:  16d0 d0b2 0000 0204 05b4 0402 080a 0019  ................
	0x0040:  db30 0000 0000 0103 0306                 .0........
21:25:22.978410 IP 192.168.254.1.57412 > 204.152.191.5.80: . ack 506544671 win 92 <nop,nop,timestamp 1694567 1021078027>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0034 aa3a 4000 3f06 4741 c0a8 fe01 cc98  .4.:@.?.GA......
	0x0020:  bf05 e044 0050 e94d 710a 1e31 421f 8010  ...D.P.Mq..1B...
	0x0030:  005c 0e73 0000 0101 080a 0019 db67 3cdc  .\.s.........g<.
	0x0040:  6a0b                                     j.
21:25:22.978644 IP 192.168.254.1.57412 > 204.152.191.5.80: P 0:240(240) ack 1 win 92 <nop,nop,timestamp 1694567 1021078027>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0124 aa3b 4000 3f06 4650 c0a8 fe01 cc98  .$.;@.?.FP......
	0x0020:  bf05 e044 0050 e94d 710a 1e31 421f 8018  ...D.P.Mq..1B...
	0x0030:  005c 1455 0000 0101 080a 0019 db67 3cdc  .\.U.........g<.
	0x0040:  6a0b 4745 5420 2f20 4854 5450 2f31 2e30  j.GET./.HTTP/1.0
	0x0050:  0d0a 5573 6572 2d41 6765 6e74 3a20 7733  ..User-Agent:.w3

[-- Attachment #4: tcpdump_2-6-27-rc1-git1_tcp_0 --]
[-- Type: application/octet-stream, Size: 1214 bytes --]

21:33:43.584625 IP 192.168.254.1.56735 > 204.152.191.5.80: S 2776174833:2776174833(0) win 5840 <mss 1460>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  002c 1487 4000 3f06 dcfc c0a8 fe01 cc98  .,..@.?.........
	0x0020:  bf05 dd9f 0050 a579 10f1 0000 0000 6002  .....P.y......`.
	0x0030:  16d0 a2b3 0000 0204 05b4                 ..........
21:33:43.805846 IP 192.168.254.1.56735 > 204.152.191.5.80: . ack 4067528717 win 5840
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0028 1488 4000 3f06 dcff c0a8 fe01 cc98  .(..@.?.........
	0x0020:  bf05 dd9f 0050 a579 10f2 f271 900d 5010  .....P.y...q..P.
	0x0030:  16d0 37e1 0000                           ..7...
21:33:43.806085 IP 192.168.254.1.56735 > 204.152.191.5.80: P 0:240(240) ack 1 win 5840
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0118 1489 4000 3f06 dc0e c0a8 fe01 cc98  ....@.?.........
	0x0020:  bf05 dd9f 0050 a579 10f2 f271 900d 5018  .....P.y...q..P.
	0x0030:  16d0 3dc3 0000 4745 5420 2f20 4854 5450  ..=...GET./.HTTP
	0x0040:  2f31 2e30 0d0a 5573 6572 2d41 6765 6e74  /1.0..User-Agent
	0x0050:  3a20 7733 6d2f 302e 352e 320d 0a41 6363  :.w3m/0.5.2..Acc

[-- Attachment #5: tcpdump_2-6-27-rc1-git1_tcp_1 --]
[-- Type: application/octet-stream, Size: 1446 bytes --]

21:31:29.392675 IP 192.168.254.1.35711 > 204.152.191.37.80: S 654709271:654709271(0) win 5840 <sackOK,timestamp 4294934889 0,mss 1460,nop,wscale 6>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  003c 937e 4000 3f06 5dd5 c0a8 fe01 cc98  .<.~@.?.].......
	0x0020:  bf25 8b7f 0050 2706 1217 0000 0000 a002  .%...P'.........
	0x0030:  16d0 a072 0000 0402 080a ffff 8169 0000  ...r.........i..
	0x0040:  0000 0204 05b4 0103 0306                 ..........
21:31:32.390480 IP 192.168.254.1.35711 > 204.152.191.37.80: S 654709271:654709271(0) win 5840 <sackOK,timestamp 4294935639 0,mss 1460,nop,wscale 6>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  003c 937f 4000 3f06 5dd4 c0a8 fe01 cc98  .<..@.?.].......
	0x0020:  bf25 8b7f 0050 2706 1217 0000 0000 a002  .%...P'.........
	0x0030:  16d0 9d84 0000 0402 080a ffff 8457 0000  .............W..
	0x0040:  0000 0204 05b4 0103 0306                 ..........
21:31:38.390344 IP 192.168.254.1.35711 > 204.152.191.37.80: S 654709271:654709271(0) win 5840 <sackOK,timestamp 4294937139 0,mss 1460,nop,wscale 6>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  003c 9380 4000 3f06 5dd3 c0a8 fe01 cc98  .<..@.?.].......
	0x0020:  bf25 8b7f 0050 2706 1217 0000 0000 a002  .%...P'.........
	0x0030:  16d0 97a8 0000 0402 080a ffff 8a33 0000  .............3..
	0x0040:  0000 0204 05b4 0103 0306                 ..........

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

On Mon, Oct 20, 2008 at 09:48:18PM +0200, Aldo Maggi wrote:
...
> moreover, i read more carefully what you and Jarek wrote above, please let me
> know if you deem still necessary that i apply the patch you provided and
> compile or if you like i compile the latest kernel or whatever.

Aldo, my advice, in case Ilpo is busy now:

Since it looks like the problem/bug isn't in the kernel, but rather
somewhere in between (router, modem etc.) which is mislead by changed
(compared to 2.6.26) order of tcp options, I doubt Ilpo needs now
these dumps so much: it should be enough to say works or doesn't work.

You have checked it works in 2 cases (without tcp_sack, and without
tcp_timestamp) when mss is the first option again. With Ilpo's patch
these two options could be still present, and mss at the beginning.
It should work because it's like 2.6.26 did this, but I think, it
would be nice to check this anyway, if it's not a problem. Then
trying the latest kernel (at least 2.6.27) with this patch should be
most useful.

Thanks,
Jarek P.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Ilpo Järvinen]

On Mon, 20 Oct 2008, Aldo Maggi wrote:

> i repeat here what i wrote there:
> 
> Ilpo,
> i'm sending herewith attached the output of
> tcpdump -i eth0 -nXX -c3 'dst port 80 and tcp-syn != 0' on topolino when:
> 1) kernel 2.6.26.6 is running on paperino and tcp_window_scaling,
> tcp_timestamps, tcp_sack are set to "1"
> 2) kernel 2.6.26.6 is running on paperino and tcp_window_scaling,
> tcp_timestamps, tcp_sack are set to "0"
> 3) kernel 2.6.27-rc1-git1 is running on paperino and tcp_window_scaling,
> tcp_timestamps, tcp_sack are set to "1"
> 4) kernel 2.6.27-rc1-git1 is running on paperino and tcp_window_scaling,
> tcp_timestamps, tcp_sack are set to "0"

Thanks, very unambiquously being told what each case is, helps a lot... :-)

Difference is: ip checksum, ipid, lsb of dstaddr, sport, seqno, tcp 
checksum, timestamp. Plus the option reordering as discussed before. Here 
are the options:

    28  0204  <
    29  05b4  <
    30  0402    0402
    31  080a    080a
    32  0019  | ffff
    33  db30  | 8169
    34  0000    0000
    35  0000    0000
    36        > 0204
    37        > 05b4
    38  0103    0103
    39  0306    0306

Could you try if tcp_window_scaling=1, tcp_sack=1, tcp_timestamps=0 also 
works, if you didn't already (it's not that obvious from the earlier 
acknowledgement you gave that these were the exact options you used or 
not)...

> moreover, i read more carefully what you and Jarek wrote above, please let me
> know if you deem still necessary that i apply the patch you provided and
> compile or if you like i compile the latest kernel or whatever.

If that ws=1,s=1,ts=0 test succeeds, then testing my patch would be useful 
too. Anyway it seems that we're dealing with some violation of spec here
(by either the peer or some middle node, 2.6.27-whatever is not doing 
something outside of spec), just trying to narrow down which of the 
options is the actual cause. We might need to try later some other 
ordering of options too to rule out possibilities by trial-and-error
(ie., unless you have a better knowledge about the devices on the path, 
information which I sort of expect to be out of (y)our reach :-)).


-- 
 i.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Ilpo Järvinen]

In general, please use reply to all when dealing with linux developers (so 
that related people & lists end up being cc'ed), we just work that way :-).
I did restore CCs for you this time.

On Mon, 20 Oct 2008, Aldo Maggi wrote:

> bear with me but i do not wish to create problems to you all, therefore
> i'd like to be sure to be doing the correct procedure before going on
> with the compilation:
> 
> i've used your patch with the sources of kernel 2.6.27-rc1 which i had
> already patched vith git1 because of problems with the compilation
> (problems which had been solved with git1 patch).
> 
> what follows is the output of patch, is it correct?
> 
> paperino:/usr/src/linux-2.6.27-rc1-git1# patch -p1 < ../patch_iarno
> patching file net/ipv4/tcp_output.c
> Hunk #1 succeeded at 371 (offset -5 lines).
> Hunk #2 succeeded at 393 (offset -5 lines).

-5 offset might well happen and patch was able to apply it right 
regardless of that (I might have had some unrelated modifications 
or so in my local dev tree which causes the line numbers to shift
a bit).

> i'll anyway go on with the compilation, but i don't want that you
> expect i do something and i do something else! :-D

I'm fine with the kernel and your procedure... :-) And also 2.6.27 won't 
make much difference to 2.6.27-rc-something I think, so you can ignore 
Jarek's suggestion to use 2.6.27+patch if you feel -rc is easier for you 
now that you've started with it. I'm fine with either kernel 
version+patch.

-- 
 i.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Ilpo Järvinen]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 2018 bytes --]

Reply to all please... ...I restored them again for you... :-)

On Mon, 20 Oct 2008, Aldo Maggi wrote:

> Il giorno Mon, 20 Oct 2008 23:55:48 +0300 (EEST)
> "Ilpo Järvinen" <ilpo.jarvinen@helsinki.fi> ha scritto:
> 
> [...]
> 
> > Could you try if tcp_window_scaling=1, tcp_sack=1, tcp_timestamps=0
> > also works, if you didn't already (it's not that obvious from the
> > earlier acknowledgement you gave that these were the exact options
> > you used or not)...
> 
> sorry! i was not precise!
> those are exactly the options i tried in my acknowledgment no. 40,
> i.e. tcp_window_scaling and tcp_sack equal to "1" and tcp_timestamps=0

Np, thanks for the confirmation. I sort of assumed this already since 
the alternative interpretation of Jarek's mails didn't make too much 
sense after all (and I jumped into this thread in between, so I just 
scanned them through with haste on the first time concentrating more
on your responses and which of the logs I should download :-)).

> > > moreover, i read more carefully what you and Jarek wrote above,
> > > please let me know if you deem still necessary that i apply the
> > > patch you provided and compile or if you like i compile the latest
> > > kernel or whatever.
> > 
> > If that ws=1,s=1,ts=0 test succeeds, then testing my patch would be
> > useful too. 
> 
> i'm right now compiling the -27-rc1 kernel, on my pc it will take at
> least 3 hrs (that is, it will finish 02.00 rome time :-D )

Ok, I'll check that tomorrow then as mine trimmed down 2.6.28-rc (ah, 
it's still -g something, no rc1 just yet) did complete already :-), just 
going to try to bombard google.it from here too and then it's the bedtime 
for me...

> should it work i'll apply your patch t0 2.6.27.2 and compile again. 

Ok, it's quite likely that both will work with the patch. Anyway, it's 
enough that you do the future tests with 2.6.27.y if we decide to try some 
other ordering (I'll try to think a bit of that tomorrow to see what 
would be to most sensible ordering).

-- 
 i.

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Aldo Maggi]

Il giorno Tue, 21 Oct 2008 00:51:26 +0300 (EEST)
"Ilpo Järvinen" <ilpo.jarvinen@helsinki.fi> ha scritto:

> Reply to all please... ...I restored them again for you... :-)

sorry! i'll be more careful in the future!


[...]

thanks :-)
aldo

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Aldo Maggi]

[-- Attachment #1: Type: text/plain, Size: 475 bytes --]


[...]

> > 
> > i'm right now compiling the -27-rc1 kernel, on my pc it will take at
> > least 3 hrs (that is, it will finish 02.00 rome time :-D )
> 

ok! the new kernel with ilpo's patch works!!
please find herewith attached the tcpdump output on eth0 on topolino 
while on paperino kernel 2.6.27-rc1-git1 with ilpo patch was running ,
the three tcp files all set to 1

[...]

as soon as i come back home i will start compilation of 2.6.27.2 with
ilpo patch

thanks 
aldo

[-- Attachment #2: tcpdump_2-6-27-rc1-git1-ilpo-tcp_1 --]
[-- Type: application/octet-stream, Size: 1457 bytes --]

07:15:43.733574 IP 192.168.254.1.57604 > 204.152.191.5.80: S 2965188623:2965188623(0) win 5840 <mss 1460,sackOK,timestamp 145214 0,nop,wscale 6>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  003c 0731 4000 3f06 ea42 c0a8 fe01 cc98  .<.1@.?..B......
	0x0020:  bf05 e104 0050 b0bd 300f 0000 0000 a002  .....P..0.......
	0x0030:  16d0 ed86 0000 0204 05b4 0402 080a 0002  ................
	0x0040:  373e 0000 0000 0103 0306                 7>........
07:15:43.943869 IP 192.168.254.1.57604 > 204.152.191.5.80: . ack 1887470968 win 92 <nop,nop,timestamp 145267 1056499011>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0034 0732 4000 3f06 ea49 c0a8 fe01 cc98  .4.2@.?..I......
	0x0020:  bf05 e104 0050 b0bd 3010 7080 8578 8010  .....P..0.p..x..
	0x0030:  005c 184c 0000 0101 080a 0002 3773 3ef8  .\.L........7s>.
	0x0040:  e543                                     .C
07:15:43.944110 IP 192.168.254.1.57604 > 204.152.191.5.80: P 0:240(240) ack 1 win 92 <nop,nop,timestamp 145267 1056499011>
	0x0000:  00a0 c543 5feb 0010 5ac5 681c 0800 4500  ...C_...Z.h...E.
	0x0010:  0124 0733 4000 3f06 e958 c0a8 fe01 cc98  .$.3@.?..X......
	0x0020:  bf05 e104 0050 b0bd 3010 7080 8578 8018  .....P..0.p..x..
	0x0030:  005c 1e2e 0000 0101 080a 0002 3773 3ef8  .\..........7s>.
	0x0040:  e543 4745 5420 2f20 4854 5450 2f31 2e30  .CGET./.HTTP/1.0
	0x0050:  0d0a 5573 6572 2d41 6765 6e74 3a20 7733  ..User-Agent:.w3

Re: tcp_sack problem Re: [Bug 11721] after upgrade to 2.6.27 i cannot navigate

[Jarek Poplawski]

On Sat, Oct 25, 2008 at 10:15:15PM +0200, Aldo Maggi wrote:
> Il giorno Tue, 21 Oct 2008 07:49:54 +0000
> Jarek Poplawski <jarkao2@gmail.com> ha scritto:
> 
> > On Tue, Oct 21, 2008 at 09:27:21AM +0200, Aldo Maggi wrote:
> > ...
> > > as soon as i've time i'll replace the modem and run some tests.
> 
> just to let you know!
> i have changed my modem with a new one.
> the bug has disappeared with no modification of the tcp files.
> this shows that the problem was due to my old zyxel.
> 
> ciao!
> aldo
> 

Aldo, I think it's a very useful information, so I forward this to the
people.

Thanks again,
Jarek P.