On Thu, 30 Aug 2018 19:01:16 +0100,
Sasha Levin <Alexander.Levin@xxxxxxxxxxxxx> wrote:
>
> From: Marc Zyngier <marc.zyngier@xxxxxxx>
>
> [ Upstream commit 3fc7c5c0cff3150e471f5fd12f59971c6d2c6513 ]
>
> pm_runtime_get_if_in_use can fail: either PM has been disabled
> altogether (-EINVAL), or the device hasn't been enabled yet (0).
> Sadly, the Rockchip IOMMU driver tends to conflate the two things
> by considering a non-zero return value as successful.
>
> This has the consequence of hiding other bugs, so let's handle this
> case throughout the driver, with a WARN_ON_ONCE so that we can try
> and work out what happened.
>
> Fixes: 0f181d3cf7d98 ("iommu/rockchip: Add runtime PM support")
> Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx>
> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
> Signed-off-by: Olof Johansson <olof@xxxxxxxxx>
> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Picking this patch on its own feels like a bad idea if CONFIG_PM is
not selected. Consider picking up 7db7a8f5638a and d1558dfd9f22 which
guarantee that things won't break.
Thanks,
M.
--
Jazz is not dead, it just smell funny.
