On Mon, Dec 4, 2023 at 11:30 AM Geert Uytterhoeven
<geert+renesas@xxxxxxxxx> wrote:
>
> On RZ/Five SMARC EVK, where probing of SDHI is deferred due to probe
> deferral of the vqmmc-supply regulator:
>
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 0 at kernel/time/timer.c:1738 __run_timers.part.0+0x1d0/0x1e8
> Modules linked in:
> CPU: 0 PID: 0 Comm: swapper Not tainted 6.7.0-rc4 #101
> Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT)
> epc : __run_timers.part.0+0x1d0/0x1e8
> ra : __run_timers.part.0+0x134/0x1e8
> epc : ffffffff800771a4 ra : ffffffff80077108 sp : ffffffc800003e60
> gp : ffffffff814f5028 tp : ffffffff8140c5c0 t0 : ffffffc800000000
> t1 : 0000000000000001 t2 : ffffffff81201300 s0 : ffffffc800003f20
> s1 : ffffffd8023bc4a0 a0 : 00000000fffee6b0 a1 : 0004010000400000
> a2 : ffffffffc0000016 a3 : ffffffff81488640 a4 : ffffffc800003e60
> a5 : 0000000000000000 a6 : 0000000004000000 a7 : ffffffc800003e68
> s2 : 0000000000000122 s3 : 0000000000200000 s4 : 0000000000000000
> s5 : ffffffffffffffff s6 : ffffffff81488678 s7 : ffffffff814886c0
> s8 : ffffffff814f49c0 s9 : ffffffff81488640 s10: 0000000000000000
> s11: ffffffc800003e60 t3 : 0000000000000240 t4 : 0000000000000a52
> t5 : ffffffd8024ae018 t6 : ffffffd8024ae038
> status: 0000000200000100 badaddr: 0000000000000000 cause: 0000000000000003
> [<ffffffff800771a4>] __run_timers.part.0+0x1d0/0x1e8
> [<ffffffff800771e0>] run_timer_softirq+0x24/0x4a
> [<ffffffff80809092>] __do_softirq+0xc6/0x1fa
> [<ffffffff80028e4c>] irq_exit_rcu+0x66/0x84
> [<ffffffff80800f7a>] handle_riscv_irq+0x40/0x4e
> [<ffffffff80808f48>] call_on_irq_stack+0x1c/0x28
> ---[ 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 MMC host structure
> containing the delayed work was freed, and now contains an invalid work
> function pointer.
>
> Fix this by cancelling any pending delayed work before releasing the
> MMC host structure.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> This is v2 of "[RFC] mmc: tmio: Cancel delayed work before freeing
> host".
>
> v2:
> - Move cancel_delayed_work_sync() call from tmio_mmc_host_free() to
> mmc_free_host(),
> - Correct explanation from missing pin control to vqmmc-supply probe
> deferral,
> - Update backtrace.
> ---
> drivers/mmc/core/host.c | 1 +
> 1 file changed, 1 insertion(+)
>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Cheers,
Prabhakar
> diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
> index 096093f7be006353..2f51db4df1a8571b 100644
> --- a/drivers/mmc/core/host.c
> +++ b/drivers/mmc/core/host.c
> @@ -692,6 +692,7 @@ EXPORT_SYMBOL(mmc_remove_host);
> */
> void mmc_free_host(struct mmc_host *host)
> {
> + cancel_delayed_work_sync(&host->detect);
> mmc_pwrseq_free(host);
> put_device(&host->class_dev);
> }
> --
> 2.34.1
>
>
