Re: [git pull] drm for 4.19-rc1

[John Stultz]

On Tue, Aug 14, 2018 at 7:53 PM, Dave Airlie <airlied@xxxxxxxxx> wrote:
> This is the main drm pull request for 4.19.
>
> Rob has some new hardware support for new qualcomm hw that I'll send along
> separately. This has the display part of it, the remaining pull is for the
> acceleration engine.
>
> This also contains a wound-wait/wait-die mutex rework, Peter has acked it
> for merging via my tree.
>
> Otherwise mostly the usual level of activity.

Hey Folks,
  Since this branch landed, I've been seeing the following panic on
bootup w/ the HiKey board (which uses the hisilicon/kirin drm driver):

[    8.088388] Unable to handle kernel read from unreadable memory at
virtual address 0000000000000030
[    8.088393] Mem abort info:
[    8.088397]   ESR = 0x96000005
[    8.088402]   Exception class = DABT (current EL), IL = 32 bits
[    8.088406]   SET = 0, FnV = 0
[    8.088410]   EA = 0, S1PTW = 0
[    8.088413] Data abort info:
[    8.088417]   ISV = 0, ISS = 0x00000005
[    8.088421]   CM = 0, WnR = 0
[    8.088427] user pgtable: 4k pages, 39-bit VAs, pgdp = (____ptrval____)
[    8.088432] [0000000000000030] pgd=0000000000000000, pud=0000000000000000
[    8.088443] Internal error: Oops: 96000005 [#1] PREEMPT SMP
[    8.088453] CPU: 5 PID: 1414 Comm: kworker/5:2 Tainted: G        W
       4.18.0-07439-gbf1fba4 #633
[    8.088457] Hardware name: HiKey Development Board (DT)
[    8.088474] Workqueue: events adv7511_hpd_work
[    8.088482] pstate: 40400005 (nZcv daif +PAN -UAO)
[    8.088493] pc : drm_sysfs_hotplug_event+0x40/0x78
[    8.088499] lr : drm_sysfs_hotplug_event+0x40/0x78
[    8.088502] sp : ffffff800ba73d20
[    8.088506] x29: ffffff800ba73d20 x28: 0000000000000000
[    8.088514] x27: ffffff8009293cd8 x26: ffffffc074e55938
[    8.088522] x25: 0000000000000000 x24: ffffffc07ff85000
[    8.088530] x23: ffffffc0742c4a78 x22: ffffffc07ff86c00
[    8.088537] x21: ffffffc0750d0e00 x20: 0000000000000000
[    8.088545] x19: ffffff8009009a48 x18: 0000000000000000
[    8.088552] x17: 0000000000000000 x16: ffffffc074fbde80
[    8.088560] x15: 0000000000000000 x14: ffffffc005f96c00
[    8.088568] x13: 00000040770c9000 x12: 0000000034d5d91d
[    8.088575] x11: 0000000000000000 x10: 0000000000000990
[    8.088582] x9 : ffffff800ba739b0 x8 : ffffff800913e000
[    8.088589] x7 : 0000000000000000 x6 : ffffff8009009a48
[    8.088596] x5 : ffffff80090588d0 x4 : 0000000000000000
[    8.088602] x3 : ffffff8009009a48 x2 : 0000000000000000
[    8.088608] x1 : 18701cfc97cf1200 x0 : 0000000000000000
[    8.120775] Process kworker/5:2 (pid: 1414, stack limit = 0x(____ptrval____))
[    8.120778] Call trace:
[    8.120787]  drm_sysfs_hotplug_event+0x40/0x78
[    8.120794]  drm_kms_helper_hotplug_event+0x14/0x40
[    8.120800]  adv7511_hpd_work+0x64/0xe0
[    8.120807]  process_one_work+0x12c/0x320
[    8.120814]  worker_thread+0x48/0x458
[    8.126654]  kthread+0xf8/0x128
[    8.126661]  ret_from_fork+0x10/0x18
[    8.126672] Code: aa0003f4 52800020 a902ffa2 94006637 (f9401a80)
[    8.135638] ---[ end trace cf7120942e6f40fa ]---

And earlier in boot we see:

[    4.620909] kirin-drm f4100000.ade: bound f4107800.dsi (ops dsi_ops)
[    4.627304] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    4.633935] [drm] No driver support for vblank timestamp query.
[    4.732910] kirin-drm f4100000.ade: [drm:drm_fb_helper_fbdev_setup]
*ERROR* Failed to set fbdev configuration
[    4.742948] [drm:kirin_drm_bind] *ERROR* failed to initialize fbdev.
[    4.749585] kirin-drm f4100000.ade: master bind failed: -22
[    4.755218] dw-dsi: probe of f4107800.dsi failed with error -22

I've also seen similar trouble w/ the HiKey960 which uses a similar
but still out of tree driver that also utilizes the cma fbhelper code,
which makes me suspect it has to do with the drm/cma-helper changes
below:

> Noralf TrÃnnes (15):
>       drm/file: Don't set master on in-kernel clients
>       drm: Make ioctls available for in-kernel clients
>       drm: Begin an API for in-kernel clients
>       drm/fb-helper: Add generic fbdev emulation .fb_probe function
>       drm/pl111: Set .gem_prime_vmap and .gem_prime_mmap
>       drm/cma-helper: Use the generic fbdev emulation
>       drm/debugfs: Add internal client debugfs file
>       drm/fb-helper: Finish the generic fbdev emulation
>       drm/tinydrm: Use drm_fbdev_generic_setup()
>       drm/cma-helper: Remove drm_fb_cma_fbdev_init_with_funcs()

Though I've not yet had time to bisect this down tonight.

I'll spend some more time on this tomorrow, but wanted to give folks a
heads up in the meantime.

thanks
-john