Commit 427f39e2 authored Jan 28, 2020 by Ben Skeggs Committed by Greg Kroah-Hartman Feb 24, 2020

drm/nouveau/disp/nv50-: prevent oops when no channel method map provided

[ Upstream commit 0e6176c6d286316e9431b4f695940cfac4ffe6c2 ]

The implementations for most channel types contains a map of methods to
priv registers in order to provide debugging info when a disp exception
has been raised.

This info is missing from the implementation of PIO channels as they're
rather simplistic already, however, if an exception is raised by one of
them, we'd end up triggering a NULL-pointer deref.  Not ideal...

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206299


Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 39c69322

drivers/gpu/drm/nouveau/nvkm/engine/disp/channv50.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -74,6 +74,8 @@ nv50_disp_chan_mthd(struct nv50_disp_chan *chan, int debug)

		if (debug > subdev->debug)
		return;
		if (!mthd)
		return;

		for (i = 0; (list = mthd->data[i].mthd) != NULL; i++) {
		u32 base = chan->head * mthd->addr;