6.1-stable review patch. If anyone has any objections, please let me know.
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From: Johan Hovold johan@kernel.org
commit 500e1368e46928f4b2259612dcabb6999afae2a6 upstream.
Make sure to drop the reference taken to the AHB platform device when looking up its driver data while enabling the SMMU.
Note that holding a reference to a device does not prevent its driver data from going away.
Fixes: 89c788bab1f0 ("ARM: tegra: Add SMMU enabler in AHB") Cc: stable@vger.kernel.org # 3.5 Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: Thierry Reding treding@nvidia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/amba/tegra-ahb.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/amba/tegra-ahb.c +++ b/drivers/amba/tegra-ahb.c @@ -144,6 +144,7 @@ int tegra_ahb_enable_smmu(struct device_ if (!dev) return -EPROBE_DEFER; ahb = dev_get_drvdata(dev); + put_device(dev); val = gizmo_readl(ahb, AHB_ARBITRATION_XBAR_CTRL); val |= AHB_ARBITRATION_XBAR_CTRL_SMMU_INIT_DONE; gizmo_writel(ahb, val, AHB_ARBITRATION_XBAR_CTRL);