From: "Luck, Tony" <tony.luck@intel.com>
To: Daniel Vetter <daniel.vetter@ffwll.ch>,
        "Wang, Rui Y" <rui.y.wang@intel.com>
CC: Dave Airlie <airlied@redhat.com>, "Clark, Rob" <robdclark@gmail.com>,
        "Roper, Matthew D" <matthew.d.roper@intel.com>,
        "Chen, Gong" <gong.chen@intel.com>, Borislav Petkov <bp@alien8.de>,
        "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>
Subject: RE: drm/mgag200: doesn't work in panic context
Thread-Topic: drm/mgag200: doesn't work in panic context
Thread-Index: AQHQr+f6h6WDfeOs7EWw+ewemqNMo52++joAgAAN1UA=
Date: Fri, 26 Jun 2015 18:30:32 +0000
Message-ID: <3908561D78D1C84285E8C5FCA982C28F32AA062A@ORSMSX114.amr.corp.intel.com>
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>> I'm here to report two panics which hang forever (the machine cannot reboot). It is because mgag200 doesn't work in panic context. It sleeps and allocates memory non-atomically.
>
> This is the same for all drm drivers, the drm atomic handling with
> fbcon/fbdev is totally broken. It would be serious work to fix this
> properly.

It's a serious problem when a server crashes ... even worse when it hangs while doing so
because we have to rely on some other agent to notice the hung server and go poke it
with a stick.

If it is too hard to fix all of the drivers, is it possible to attack this in the allocator?

-Tony
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