On Thu, 2015-06-25 at 14:35 -0700, Dmitry Torokhov wrote:

On Thu, Jun 25, 2015 at 05:31:25PM -0400, Stephen Chandler Paul 
wrote:

quoted

On Thu, 2015-06-25 at 13:32 -0700, Dmitry Torokhov wrote:

quoted

On Thu, Jun 25, 2015 at 03:25:10PM -0400, cpaul@redhat.com wrote:

quoted

From: Stephen Chandler Paul <redacted>

A big problem with the current i8042 debugging option is that 
it 
outputs
data going to and from the keyboard by default. As a result, 
many 
dmesg
logs uploaded by users will unintentionally contain sensitive 
information
such as their password, as such it's probably a good idea not 
to 
output
data coming from the keyboard unless specifically enabled by 
the 
user.

Signed-off-by: Stephen Chandler Paul <redacted>
Reviewed-by: Benjamin Tissoires <redacted>
---
 Documentation/kernel-parameters.txt |  7 +++++++
 drivers/input/serio/i8042.c         | 25 +++++++++++++++++++++
----
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/Documentation/kernel-parameters.txt 

b/Documentation/kernel-parameters.txt
index ae44749..9e00234 100644

--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt

@@ -1304,6 +1304,13 @@ bytes respectively. Such letter suffixes 

can 
also be entirely omitted.
 			     <bus_id>,<clkrate>
 
 	i8042.debug	[HW] Toggle i8042 debug mode
+	i8042.debug_kbd [HW] Enable printing of interrupt data 

from the KBD port
+			     As a side effect, this option 
will 
mask some of the
+			     interrupts sent back from the 
keyboard during the
+			     initialization of the KBD port on 
the 
i8042, if you
+			     need to see this, you will need 
to 
enable this
+			     option.

Hmm, can we maybe use the bus notifier and react to
BUS_NOTIFY_BOUND_DRIVER/BUS_NOTIFY_UNBIND_DRIVER to decide if we 
want 
to
see keyboard data stream?

Out of curiosity, are there devices that aren't keyboards that 
actually
make use of the KBD port? It was my understanding keyboards used 
the
KBD port, and everything else uses the AUX port.

On desktops if you plug keyboard into mouse port and mouse into 
keyboard
port there is a chance they will work (depends on the BIOS). But I 
was
not talking about supporting that  necessarily, but use bus notifiers 
to
allow seeing KBC port stream until the driver is fully bound and when 
it
is to be unbound from the KBC port (whatever driver that might be).

Alright, I'm following you now. This is definitely doable, we don't
need it for our use case (this is mostly just to stop people from
accidentally giving their passwords to us), but I'll be happy to add it
and get back to you with the new version of the patch when I'm
finished.

Cheers,
	Stephen Chandler Paul

Thanks.