On 5/6/2022 6:00 PM, Dmitry Baryshkov wrote:
As msm_drm_uninit() is called from the msm_drm_init() error path,
additional care should be necessary as not to call the free_irq() for
the IRQ that was not requested before (because an error occured earlier
than the request_irq() call).
This fixed the issue reported with the following backtrace:
[ 8.571329] Trying to free already-free IRQ 187
[ 8.571339] WARNING: CPU: 0 PID: 76 at kernel/irq/manage.c:1895 free_irq+0x1e0/0x35c
[ 8.588746] Modules linked in: pmic_glink pdr_interface fastrpc qrtr_smd snd_soc_hdmi_codec msm fsa4480 gpu_sched drm_dp_aux_bus qrtr i2c_qcom_geni crct10dif_ce qcom_stats qcom_q6v5_pas drm_display_helper gpi qcom_pil_info drm_kms_helper qcom_q6v5 qcom_sysmon qcom_common qcom_glink_smem qcom_rng mdt_loader qmi_helpers phy_qcom_qmp ufs_qcom typec qnoc_sm8350 socinfo rmtfs_mem fuse drm ipv6
[ 8.624154] CPU: 0 PID: 76 Comm: kworker/u16:2 Not tainted 5.18.0-rc5-next-20220506-00033-g6cee8cab6089-dirty #419
[ 8.624161] Hardware name: Qualcomm Technologies, Inc. SM8350 HDK (DT)
[ 8.641496] Workqueue: events_unbound deferred_probe_work_func
[ 8.647510] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 8.654681] pc : free_irq+0x1e0/0x35c
[ 8.658454] lr : free_irq+0x1e0/0x35c
[ 8.662228] sp : ffff800008ab3950
[ 8.665642] x29: ffff800008ab3950 x28: 0000000000000000 x27: ffff16350f56a700
[ 8.672994] x26: ffff1635025df080 x25: ffff16350251badc x24: ffff16350251bb90
[ 8.680343] x23: 0000000000000000 x22: 00000000000000bb x21: ffff16350e8f9800
[ 8.687690] x20: ffff16350251ba00 x19: ffff16350cbd5880 x18: ffffffffffffffff
[ 8.695039] x17: 0000000000000000 x16: ffffa2dd12179434 x15: ffffa2dd1431d02d
[ 8.702391] x14: 0000000000000000 x13: ffffa2dd1431d028 x12: 662d79646165726c
[ 8.709740] x11: ffffa2dd13fd2438 x10: 000000000000000a x9 : 00000000000000bb
[ 8.717111] x8 : ffffa2dd13fd23f0 x7 : ffff800008ab3750 x6 : 00000000fffff202
[ 8.724487] x5 : ffff16377e870a18 x4 : 00000000fffff202 x3 : ffff735a6ae1b000
[ 8.731851] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff1635015f8000
[ 8.739217] Call trace:
[ 8.741755] free_irq+0x1e0/0x35c
[ 8.745198] msm_drm_uninit.isra.0+0x14c/0x294 [msm]
[ 8.750548] msm_drm_bind+0x28c/0x5d0 [msm]
[ 8.755081] try_to_bring_up_aggregate_device+0x164/0x1d0
[ 8.760657] __component_add+0xa0/0x170
[ 8.764626] component_add+0x14/0x20
[ 8.768337] dp_display_probe+0x2a4/0x464 [msm]
[ 8.773242] platform_probe+0x68/0xe0
[ 8.777043] really_probe.part.0+0x9c/0x28c
[ 8.781368] __driver_probe_device+0x98/0x144
[ 8.785871] driver_probe_device+0x40/0x140
[ 8.790191] __device_attach_driver+0xb4/0x120
[ 8.794788] bus_for_each_drv+0x78/0xd0
[ 8.798751] __device_attach+0xdc/0x184
[ 8.802713] device_initial_probe+0x14/0x20
[ 8.807031] bus_probe_device+0x9c/0xa4
[ 8.810991] deferred_probe_work_func+0x88/0xc0
[ 8.815667] process_one_work+0x1d0/0x320
[ 8.819809] worker_thread+0x14c/0x444
[ 8.823688] kthread+0x10c/0x110
[ 8.827036] ret_from_fork+0x10/0x20
Reported-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Fixes: f026e431cf86 ("drm/msm: Convert to Linux IRQ interfaces")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
I was looking at how other drm drivers handle this and they also have a
similar logic. So this is a good addition and thanks to the -EDEFER path
getting exposed we finally uncovered this.
Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_drv.c | 7 ++++++-
drivers/gpu/drm/msm/msm_kms.h | 1 +
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 4a3dda23e3e0..44485363f37a 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -113,6 +113,8 @@ static int msm_irq_postinstall(struct drm_device *dev)
static int msm_irq_install(struct drm_device *dev, unsigned int irq)
{
+ struct msm_drm_private *priv = dev->dev_private;
+ struct msm_kms *kms = priv->kms;
int ret;
if (irq == IRQ_NOTCONNECTED)
@@ -124,6 +126,8 @@ static int msm_irq_install(struct drm_device *dev, unsigned int irq)
if (ret)
return ret;
+ kms->irq_requested = true;
+
ret = msm_irq_postinstall(dev);
if (ret) {
free_irq(irq, dev);
@@ -139,7 +143,8 @@ static void msm_irq_uninstall(struct drm_device *dev)
struct msm_kms *kms = priv->kms;
kms->funcs->irq_uninstall(kms);
- free_irq(kms->irq, dev);
+ if (kms->irq_requested)
+ free_irq(kms->irq, dev);
}
struct msm_vblank_work {
diff --git a/drivers/gpu/drm/msm/msm_kms.h b/drivers/gpu/drm/msm/msm_kms.h
index ab25fff271f9..f8ed7588928c 100644
--- a/drivers/gpu/drm/msm/msm_kms.h
+++ b/drivers/gpu/drm/msm/msm_kms.h
@@ -148,6 +148,7 @@ struct msm_kms {
/* irq number to be passed on to msm_irq_install */
int irq;
+ bool irq_requested;
/* mapper-id used to request GEM buffer mapped for scanout: */
struct msm_gem_address_space *aspace;
