On Tue, 31 Oct 2023 at 16:48, Geert Uytterhoeven
<geert+renesas@xxxxxxxxx> wrote:
>
> On RZ/Five SMARC EVK, where probing of SDHI fails due to missing pin
> control:
>
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 0 at kernel/time/timer.c:1739 __run_timers.part.0+0x1e8/0x22a
> Modules linked in:
> CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-10953-ga37a67d260e6-dirty #86
> Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> epc : __run_timers.part.0+0x1e8/0x22a
> ra : __run_timers.part.0+0x130/0x22a
> epc : ffffffff8007540c ra : ffffffff80075354 sp : ffffffc800003e60
> gp : ffffffff814f5f08 tp : ffffffff8140d5c0 t0 : 0000000000046600
> t1 : 0000000000000001 t2 : ffffffff81200c10 s0 : ffffffc800003f20
> s1 : ffffffd8023bc4a0 a0 : 00000000fffee790 a1 : 0000000000000200
> a2 : 0000000000000200 a3 : ffffffff81489640 a4 : ffffffc800003e60
> a5 : 0000000000000000 a6 : 0000000000000000 a7 : ffffffc800003e68
> s2 : 0000000000200000 s3 : 0000000000000122 s4 : 0000000000000000
> s5 : ffffffffffffffff s6 : ffffffff814896c0 s7 : ffffffff814f58a0
> s8 : ffffffff80f8bec8 s9 : 0000000000000000 s10: ffffffc800003e60
> s11: ffffffff81489640 t3 : ffffffff81489678 t4 : 0000000000000240
> t5 : ffffffd8024ac018 t6 : ffffffd8024ac038
> status: 0000000200000100 badaddr: 0000000000000000 cause: 0000000000000003
> [<ffffffff8007540c>] __run_timers.part.0+0x1e8/0x22a
> [<ffffffff80075472>] run_timer_softirq+0x24/0x4a
> [<ffffffff80804ec6>] __do_softirq+0xc6/0x212
> [<ffffffff80027434>] irq_exit_rcu+0x7c/0x9a
> [<ffffffff807fcd8a>] handle_riscv_irq+0x40/0x4e
> [<ffffffff807fd7f8>] do_irq+0x40/0x68
> ---[ end trace 0000000000000000 ]---
>
> What happens?
>
> renesas_sdhi_probe()
> {
> tmio_mmc_host_alloc()
> mmc_alloc_host()
> INIT_DELAYED_WORK(&host->detect, mmc_rescan);
>
> devm_request_irq(tmio_mmc_irq);
>
> /*
> * After this, the interrupt handler may be invoked at any time
> *
> * tmio_mmc_irq()
> * {
> * __tmio_mmc_card_detect_irq()
> * mmc_detect_change()
> * _mmc_detect_change()
> * mmc_schedule_delayed_work(&host->detect, delay);
> * }
> */
>
> tmio_mmc_host_probe()
> tmio_mmc_init_ocr()
> -EPROBE_DEFER
>
> tmio_mmc_host_free()
> mmc_free_host()
> }
>
> When expire_timers() runs later, it warns because the scheduled work was
> freed, and now contains a NULL handler function pointer.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> Calling __mmc_stop_host() instead works too, but __mmc_stop_host() is an
> internal core function, and is not exported to modules yet.
>
> Perhaps this should be handled by mmc_free_host() instead?
That sounds reasonable to me. Or actually not "instead of"
__mmc_stop_host(), but rather from mmc_free_host() too.
mmc_stop_host() also needs to make sure that mmc_rescan() isn't
currently being executed, so that when setting the
"host->rescan_disable = 1;" it really takes effect.
Do you want to send a patch?
> ---
> drivers/mmc/host/tmio_mmc_core.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c
> index be7f18fd4836ab29..1e56e78a020d94b9 100644
> --- a/drivers/mmc/host/tmio_mmc_core.c
> +++ b/drivers/mmc/host/tmio_mmc_core.c
> @@ -1132,6 +1132,7 @@ EXPORT_SYMBOL_GPL(tmio_mmc_host_alloc);
>
> void tmio_mmc_host_free(struct tmio_mmc_host *host)
> {
> + cancel_delayed_work_sync(&host->mmc->detect);
> mmc_free_host(host->mmc);
> }
> EXPORT_SYMBOL_GPL(tmio_mmc_host_free);
Kind regards
Uffe
