Quoting Dmitry Baryshkov (2022-05-06 18:00:20)
> 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")
Does this supersede commit 01013ba9bbdd ("drm/msm/disp/dpu1: avoid
clearing hw interrupts if hw_intr is null during drm uninit")? I mean
that with this patch applied kms->irq_requested makes the check in
dpu_core_irq_uninstall() irrelevant because it isn't called anymore?
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> ---
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
