4.9-stable review patch. If anyone has any objections, please let me know.
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From: Marc Zyngier marc.zyngier@arm.com
commit 5f9e93fed4d45e9a8f84728aff1a8f2ab8922902 upstream.
Calling request_irq() followed by disable_irq() is usually a bad idea, specially if the interrupt can be pending, and you're not yet in a position to handle it.
This is exactly what happens on my kevin system when rebooting in a second kernel using kexec: Some interrupt is left pending from the previous kernel, and we take it too early, before disable_irq() could do anything.
Let's clear the pending interrupts as we initialize the HW, and move the interrupt request after that point. This ensures that we're in a sane state when the interrupt is requested.
Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier marc.zyngier@arm.com [adapted to recent rockchip-drm changes] Signed-off-by: Heiko Stuebner heiko@sntech.de Link: https://patchwork.freedesktop.org/patch/msgid/20180220130120.5254-2-marc.zyn... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -1386,6 +1386,9 @@ static int vop_initial(struct vop *vop) usleep_range(10, 20); reset_control_deassert(ahb_rst);
+ VOP_INTR_SET_TYPE(vop, clear, INTR_MASK, 1); + VOP_INTR_SET_TYPE(vop, enable, INTR_MASK, 0); + memcpy(vop->regsbak, vop->regs, vop->len);
for (i = 0; i < vop_data->table_size; i++) @@ -1541,17 +1544,9 @@ static int vop_bind(struct device *dev,
mutex_init(&vop->vsync_mutex);
- ret = devm_request_irq(dev, vop->irq, vop_isr, - IRQF_SHARED, dev_name(dev), vop); - if (ret) - return ret; - - /* IRQ is initially disabled; it gets enabled in power_on */ - disable_irq(vop->irq); - ret = vop_create_crtc(vop); if (ret) - goto err_enable_irq; + return ret;
pm_runtime_enable(&pdev->dev);
@@ -1561,13 +1556,19 @@ static int vop_bind(struct device *dev, goto err_disable_pm_runtime; }
+ ret = devm_request_irq(dev, vop->irq, vop_isr, + IRQF_SHARED, dev_name(dev), vop); + if (ret) + goto err_disable_pm_runtime; + + /* IRQ is initially disabled; it gets enabled in power_on */ + disable_irq(vop->irq); + return 0;
err_disable_pm_runtime: pm_runtime_disable(&pdev->dev); vop_destroy_crtc(vop); -err_enable_irq: - enable_irq(vop->irq); /* To balance out the disable_irq above */ return ret; }