Re: [07/18] thunderbolt: Handle rejected Thunderbolt devices

From: Jeremy McNicoll
Date: Mon Feb 26 2018 - 15:15:36 EST


On 2018-02-26 11:46 AM, Mika Westerberg wrote:
On Mon, Feb 26, 2018 at 11:28:16AM -0800, Jeremy McNicoll wrote:
On 2018-02-26 5:38 AM, Mika Westerberg wrote:
On Mon, Feb 26, 2018 at 12:20:29PM +0200, Mika Westerberg wrote:
On Thu, Feb 22, 2018 at 03:17:38PM -0800, Jeremy McNicoll wrote:
+ if (pkg->link_info & ICM_LINK_INFO_REJECTED) {
+ tb_info(tb, "switch at %u.%u was rejected by ICM firmware\n",
+ link, depth);

This kind of condition sounds more like an error instead of info.
Please bump this up to tb_WARN/tb_warn ideally tb_err().

No, this is not an error.

To be more clear, it is totally fine to have the firmware to reject some
devices. For example in case of the new usbonly security level the
firmware rejects other devices but the first.


Ok. Is that kind of information available to the kernel? What security
mode we are in?

ie) if (LINK_REJECTED && !USB_SECURITY)
print "Error switch %u was rejected since its not usbonly"
endif

I am sure something like that simplified pseudo code above would
be somewhat useful to users when debugging.

That's why it is on info level so it goes to dmesg but does not scare
the user :-)


The point I am trying to make is that it would be nice to be able to
know WHY the link was rejected and not just that it was rejected.