github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-06 21:45:45 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

drm/msm/hdmi: Remove spurious IRQF_ONESHOT flag

Browse Source 
[ Upstream commit 088604d37e ]

Quoting the header comments, IRQF_ONESHOT is "Used by threaded interrupts
which need to keep the irq line disabled until the threaded handler has
been run.". When applied to an interrupt that doesn't request a threaded
irq then IRQF_ONESHOT has a lesser known (undocumented?) side effect,
which it to disable the forced threading of irqs. For "normal" kernels
if there is no thread_fn then IRQF_ONESHOT is a nop.

In this case disabling forced threading is not appropriate because the
driver calls wake_up_all() (via msm_hdmi_i2c_irq) and also directly uses
the regular spinlock API for locking (in msm_hdmi_hdcp_irq() ). Neither
of these APIs can be called from no-thread interrupt handlers on
PREEMPT_RT systems.

Fix this by removing IRQF_ONESHOT.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220201174734.196718-3-daniel.thompson@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Stable-dep-of: 152d394842 ("drm/msm/hdmi: fix IRQ lifetime")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Daniel Thompson 2022-02-01 17:47:33 +00:00 committed by Greg Kroah-Hartman
parent 5dbb47ee89
commit 8225bdaec5
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/gpu/drm/msm/hdmi/hdmi.c
View File

@ -327,7 +327,7 @@ int msm_hdmi_modeset_init(struct hdmi *hdmi,
} }
ret = devm_request_irq(&pdev->dev, hdmi->irq, ret = devm_request_irq(&pdev->dev, hdmi->irq,
msm_hdmi_irq, IRQF_TRIGGER_HIGH | IRQF_ONESHOT, msm_hdmi_irq, IRQF_TRIGGER_HIGH,
"hdmi_isr", hdmi); "hdmi_isr", hdmi);
if (ret < 0) { if (ret < 0) {
DRM_DEV_ERROR(dev->dev, "failed to request IRQ%u: %d\n", DRM_DEV_ERROR(dev->dev, "failed to request IRQ%u: %d\n",