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From: Nix <nix@esperi.org.uk>
To: Johan Hovold <johan@kernel.org>
Cc: Paul Martin <pm@debian.org>,
	Daniel Silverstone <dsilvers@debian.org>,
	Oliver Neukum <oliver@neukum.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-kernel@vger.kernel.org
Subject: Re: [3.16.1 BISECTED REGRESSION]: Simtec Entropy Key (cdc-acm) broken in 3.16
Date: Wed, 22 Oct 2014 10:31:17 +0100	[thread overview]
Message-ID: <871tq04fiy.fsf@spindle.srvr.nix> (raw)
In-Reply-To: <20141014083432.GB7958@localhost> (Johan Hovold's message of "Tue, 14 Oct 2014 10:34:32 +0200")

On 14 Oct 2014, Johan Hovold verbalised:

> On Sun, Oct 12, 2014 at 10:36:30PM +0100, Nix wrote:
>> I have checked: this code is being executed against a symlink that
>> points to /dev/ttyACM0, and the tcsetattr() succeeds. (At least, it's
>> succeeding on the kernel I'm running now, but of course that's 3.16.5
>> with this commit reverted...)
>
> You could verify that by enabling debugging in the cdc-acm driver and
> making sure that the corresponding control messages are indeed sent on
> close.

I have a debugging dump at
<http://www.esperi.org.uk/~nix/temporary/cdc-acm.log>; it's fairly
voluminous because the ekeyd is constantly doing USB reads, but the end
says

Oct 22 10:19:13 fold kern debug: : [   88.423970] cdc_acm 2-1:1.0: acm_tty_close
Oct 22 10:19:13 fold kern debug: : [   88.424012] cdc_acm 2-1:1.0: acm_port_shutdown
Oct 22 10:19:13 fold kern debug: : [   88.440038] cdc_acm 2-1:1.0: acm_ctrl_msg - rq 0x22, val 0x0, len 0x0, result 0
Oct 22 10:19:13 fold kern debug: : [   88.440038] cdc_acm 2-1:1.0: acm_ctrl_irq - urb shutting down with status: -2
Oct 22 10:19:13 fold kern debug: : [   88.440038] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 0, len 0
Oct 22 10:19:13 fold kern debug: : [   88.440038] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.447588] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 1, len 0
Oct 22 10:19:13 fold kern debug: : [   88.447613] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.448575] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 2, len 0
Oct 22 10:19:13 fold kern debug: : [   88.448599] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.449576] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 3, len 0
Oct 22 10:19:13 fold kern debug: : [   88.449599] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.450578] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 4, len 0
Oct 22 10:19:13 fold kern debug: : [   88.450602] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.451573] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 5, len 0
Oct 22 10:19:13 fold kern debug: : [   88.451596] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.452574] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 6, len 0
Oct 22 10:19:13 fold kern debug: : [   88.452597] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.453567] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 7, len 0
Oct 22 10:19:13 fold kern debug: : [   88.453588] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.454570] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 8, len 0
Oct 22 10:19:13 fold kern debug: : [   88.454592] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.462591] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 9, len 0
Oct 22 10:19:13 fold kern debug: : [   88.462619] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.463568] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 10, len 0
Oct 22 10:19:13 fold kern debug: : [   88.463590] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.464564] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 11, len 0
Oct 22 10:19:13 fold kern debug: : [   88.464585] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.465578] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 12, len 0
Oct 22 10:19:13 fold kern debug: : [   88.465602] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2
Oct 22 10:19:13 fold kern debug: : [   88.466566] cdc_acm 2-1:1.1: acm_read_bulk_callback - urb 13, len 0
Oct 22 10:19:13 fold kern debug: : [   88.466587] cdc_acm 2-1:1.1: acm_read_bulk_callback - non-zero urb status: -2

which looks, hm, a bit suspicious to me.

> But you haven't seen any fw crashes since you reverted the commit in
> question?

Not a one.

> Another thing you could try is to add back the 
>
> 	acm_set_control(acm, 0);
>
> just after the dev_info message in probe.

Tried that (with, obviously, the commit not reverted) -- rebooted, and

BytesRead=0
BytesWritten=0
ConnectionNonces=0
ConnectionPackets=0
ConnectionRekeys=0
ConnectionResets=0
ConnectionTime=46
EntropyRate=0
FipsFrameRate=0
FrameByteLast=0
FramesOk=0
FramingErrors=0
KeyDbsdShannonPerByteL=0
KeyDbsdShannonPerByteR=0
KeyEnglishBadness=No failure
KeyRawBadness=0
KeyRawShannonPerByteL=0
KeyRawShannonPerByteR=0
KeyRawShannonPerByteX=0
KeyShortBadness=efm_ok
KeyTemperatureC=-273.15
KeyTemperatureF=-459.67
KeyTemperatureK=0
KeyVoltage=0
PacketErrors=0
PacketOK=0
ReadRate=0
TotalEntropy=0
WriteRate=0

So that doesn't help.

-- 
NULL && (void)

  parent reply	other threads:[~2014-10-22  9:31 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-31 23:07 [3.16.1 REGRESSION]: Simtec Entropy Key (cdc-acm) broken in 3.16 Nix
2014-09-01 11:09 ` Oliver Neukum
2014-09-04 23:40   ` Nix
2014-09-05  7:59     ` Oliver Neukum
2014-09-05 15:17       ` Nix
2014-09-08  7:21         ` Oliver Neukum
2014-09-08  7:58           ` Nix
2014-10-11 19:05     ` [3.16.1 BISECTED " Nix
2014-10-11 19:51       ` Paul Martin
2014-10-11 22:24         ` Nix
2014-10-12 11:14           ` Paul Martin
2014-10-12 18:58           ` Johan Hovold
2014-10-12 21:36             ` Nix
2014-10-14  8:34               ` Johan Hovold
2014-10-14 14:44                 ` Nix
2014-10-17 13:21                 ` Nix
2014-10-19 13:45                   ` Johan Hovold
2014-10-22  9:31                 ` Nix [this message]
2014-10-22 10:14                   ` Johan Hovold
2014-10-22 14:00                     ` Nix
2014-10-22 15:36                     ` Nix
2014-10-24 11:14                       ` Johan Hovold
2014-10-24 15:08                         ` Nix
2014-10-31 16:44                         ` Nix
2014-11-05 11:56                           ` Johan Hovold
2014-11-05 15:14                             ` Nix
2014-11-05 15:46                               ` Daniel Silverstone
2014-11-05 18:14                               ` Johan Hovold
2014-11-06 13:49                                 ` Nix
2014-11-06 17:04                                   ` Johan Hovold
2014-11-06 17:08                                     ` [PATCH] USB: cdc-acm: add quirk for control-line state requests Johan Hovold
2014-11-07  9:05                                       ` Oliver Neukum
2014-11-07  9:16                                         ` Johan Hovold
2014-11-07 10:23                                           ` Oliver Neukum
2014-11-06 17:14                                     ` [3.16.1 BISECTED REGRESSION]: Simtec Entropy Key (cdc-acm) broken in 3.16 Nix

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