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Subject: Re: [PATCH v2 12/15] ath10k: use new module_firmware_crashed()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Luis Chamberlain <mcgrof@kernel.org>, jeyu@kernel.org
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Date:   Sat, 16 May 2020 15:50:55 +0200
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On Sat, 2020-05-16 at 15:24 +0200, Johannes Berg wrote:

> Instead of the kernel taint, IMHO you should provide an annotation in
> sysfs (or somewhere else) for the *struct device* that had its firmware
> crash. Or maybe, if it's too complex to walk the entire hierarchy
> checking for that, have a uevent, or add the ability for the kernel to
> print out elsewhere in debugfs the list of devices that crashed at some

I mean sysfs, oops.


In addition, look what we have in iwl_trans_pcie_removal_wk(). If we
detect that the device is really wedged enough that the only way we can
still try to recover is by completely unbinding the driver from it, then
we give userspace a uevent for that. I don't remember exactly how and
where that gets used (ChromeOS) though, but it'd be nice to have that
sort of thing as part of the infrastructure, in a sort of two-level
notification?

Level 1: firmware crashed, but we're recovering, at least mostly, and
it's more informational

Level 2: device is wedged, going to try to recover by some more forceful
means (perhaps some devices can be power-cycled? etc.) but (more) state
would be lost in these cases?

Still don't think a kernel taint is appropriate for either of these.

johannes