drm: vc4: WARNING: CPU: 2 PID: 172 at kernel/irq/chip.c:244 __irq_startup+0x9c/0xa8

[Marc Zyngier]

On Fri, 08 Dec 2017 22:44:27 +0000,
Stefan Wahren wrote:
> 
> Hi,
> 
> the commit 253696ccd613 ("drm/vc4: Account for interrupts in
> flight") triggers a warning during boot of Raspberry Pi 2 with
> multi_v7_defconfig:
> 
> [    7.962699] vc4_hdmi 3f902000.hdmi: vc4-hdmi-hifi <-> 3f902000.hdmi mapping ok
> [    7.962732] vc4_hdmi 3f902000.hdmi: ASoC: no DMI vendor name!
> [    7.973355] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
> [    7.973651] vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops [vc4])
> [    7.973788] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
> [    7.974157] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4])
> [    7.974464] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4])
> [    7.974746] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4])
> [    8.018820] ------------[ cut here ]------------
> [    8.018861] WARNING: CPU: 2 PID: 172 at kernel/irq/chip.c:244 __irq_startup+0x9c/0xa8
> [    8.018868] Modules linked in: vc4(+) snd_soc_core ac97_bus snd_pcm_dmaengine snd_pcm snd_timer snd soundcore cec
> [    8.018911] CPU: 2 PID: 172 Comm: systemd-udevd Not tainted 4.15.0-rc1-00291-g75f64f6 #10
> [    8.018914] Hardware name: BCM2835
> [    8.018950] [<c03115a4>] (unwind_backtrace) from [<c030c6b4>] (show_stack+0x10/0x14)
> [    8.018970] [<c030c6b4>] (show_stack) from [<c0cfc3b0>] (dump_stack+0x88/0xa4)
> [    8.018993] [<c0cfc3b0>] (dump_stack) from [<c03430cc>] (__warn+0xe4/0x110)
> [    8.019012] [<c03430cc>] (__warn) from [<c03431c4>] (warn_slowpath_null+0x3c/0x48)
> [    8.019029] [<c03431c4>] (warn_slowpath_null) from [<c0391370>] (__irq_startup+0x9c/0xa8)
> [    8.019045] [<c0391370>] (__irq_startup) from [<c03913c0>] (irq_startup+0x44/0x134)
> [    8.019061] [<c03913c0>] (irq_startup) from [<c038f360>] (enable_irq+0x34/0x6c)
> [    8.019210] [<c038f360>] (enable_irq) from [<bf0a8380>] (vc4_irq_postinstall+0x14/0x34 [vc4])
> [    8.019338] [<bf0a8380>] (vc4_irq_postinstall [vc4]) from [<c0816a98>] (drm_irq_install+0xc0/0x134)
> [    8.019456] [<c0816a98>] (drm_irq_install) from [<bf0ab0c8>] (vc4_v3d_bind+0x12c/0x238 [vc4])

The sequence "request_irq/enable" feels pretty odd, given that the
interrupt wasn't requested with NOAUTOEN. What are the expected
semantics of that patch?

Thanks,

	M.

-- 
Jazz is not dead, it just smell funny.