<html><body><p> <pre> Hi Krzysztof, Thanks for the reviews. On Wed, 2024-05-08 at 22:36 +0200, Krzysztof Kozlowski wrote: > > External email : Please do not click links or open attachments until > you have verified the sender or the content. > On 08/05/2024 11:51, Jason-JH.Lin wrote: > > When we run kernel with lockdebug option, we will get the BUG > below: > > [ 106.692124] BUG: sleeping function called from invalid context > at drivers/base/power/runtime.c:1164 > > [ 106.692190] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, > pid: 3616, name: kworker/u17:3 > > Trim logs from irrelevant context. timestamps are useless his. > Registers > as well. Addresses of stacktrace as well and better just decode it. > OK, I'll remove the useless timestamps and registers. > > > [ 106.692226] preempt_count: 1, expected: 0 > > [ 106.692254] RCU nest depth: 0, expected: 0 > > [ 106.692282] INFO: lockdep is turned off. > > [ 106.692306] irq event stamp: 0 > > [ 106.692331] hardirqs last enabled at (0): [<0000000000000000>] > 0x0 > > [ 106.692376] hardirqs last disabled at (0): [<ffffffee15d37fa0>] > copy_process+0xc90/0x2ac0 > > [ 106.692429] softirqs last enabled at (0): [<ffffffee15d37fc4>] > copy_process+0xcb4/0x2ac0 > > [ 106.692473] softirqs last disabled at (0): [<0000000000000000>] > 0x0 > > [ 106.692513] CPU: 1 PID: 3616 Comm: kworker/u17:3 Not tainted > 6.1.87-lockdep-14133-g26e933aca785 #1 > 6839942e1cf34914b0a366137843dd2366f52aa9 > > [ 106.692556] Hardware name: Google Ciri sku0/unprovisioned board > (DT) > > [ 106.692586] Workqueue: imgsys_runner imgsys_runner_func > > [ 106.692638] Call trace: > > [ 106.692662] dump_backtrace+0x100/0x120 > > [ 106.692702] show_stack+0x20/0x2c > > [ 106.692737] dump_stack_lvl+0x84/0xb4 > > [ 106.692775] dump_stack+0x18/0x48 > > [ 106.692809] __might_resched+0x354/0x4c0 > > [ 106.692847] __might_sleep+0x98/0xe4 > > [ 106.692883] __pm_runtime_resume+0x70/0x124 > > [ 106.692921] cmdq_mbox_send_data+0xe4/0xb1c > > [ 106.692964] msg_submit+0x194/0x2dc > > [ 106.693003] mbox_send_message+0x190/0x330 > > [ 106.693043] imgsys_cmdq_sendtask+0x1618/0x2224 > > [ 106.693082] imgsys_runner_func+0xac/0x11c > > [ 106.693118] process_one_work+0x638/0xf84 > > [ 106.693158] worker_thread+0x808/0xcd0 > > [ 106.693196] kthread+0x24c/0x324 > > [ 106.693231] ret_from_fork+0x10/0x20 > > > > We found that there is a spin_lock_irqsave protection in > msg_submit() > > of mailbox.c and it is in the atomic context. > > So when cmdq driver calls pm_runtime_get_sync() in > cmdq_mbox_send_data(), > > it will get this BUG report. > > > > 1. Change pm_runtime_get_sync() to pm_runtime_get() to avoid using > sleep > > in atomic context. > > 2. Move clk_bulk_enable() outside cmdq_runtime_resume() to ensure > GCE > > clocks are enabled before configuring GCE register. > > 3. Add used_count to avoid cmdq_runtime_suspend() being called > before > > calling cmdq_runtime_resume(). > > > > Fixes: 8afe816b0c99 ("mailbox: mtk-cmdq-mailbox: Implement Runtime > PM with autosuspend") > > Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com> > > --- > > drivers/mailbox/mtk-cmdq-mailbox.c | 24 +++++++++++++++--------- > > 1 file changed, 15 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c > b/drivers/mailbox/mtk-cmdq-mailbox.c > > index 033aff11f87c..b50f42e69aab 100644 > > --- a/drivers/mailbox/mtk-cmdq-mailbox.c > > +++ b/drivers/mailbox/mtk-cmdq-mailbox.c > > @@ -82,6 +82,7 @@ struct cmdq { > > const struct gce_plat*pdata; > > struct cmdq_thread*thread; > > struct clk_bulk_dataclocks[CMDQ_GCE_NUM_MAX]; > > +atomic_tused_count; > > boolsuspended; > > }; > > > > @@ -317,14 +318,21 @@ static int cmdq_runtime_resume(struct device > *dev) > > { > > struct cmdq *cmdq = dev_get_drvdata(dev); > > > > -return clk_bulk_enable(cmdq->pdata->gce_num, cmdq->clocks); > > +atomic_inc(&cmdq->used_count); > > Do not implement own runtime PM counter... > > > +return 0; > > } > > > > static int cmdq_runtime_suspend(struct device *dev) > > { > > struct cmdq *cmdq = dev_get_drvdata(dev); > > > > +if (atomic_read(&cmdq->used_count) == 0) { > > +dev_warn(dev, "%s when used_count is 0!", __func__); > > +return -EINVAL; > > +} > > + > > clk_bulk_disable(cmdq->pdata->gce_num, cmdq->clocks); > > +atomic_dec(&cmdq->used_count); > > return 0; > > } > > > > @@ -392,9 +400,8 @@ static int cmdq_mbox_send_data(struct mbox_chan > *chan, void *data) > > /* Client should not flush new tasks if suspended. */ > > WARN_ON(cmdq->suspended); > > > > -ret = pm_runtime_get_sync(cmdq->mbox.dev); > > -if (ret < 0) > > -return ret; > > +WARN_ON(pm_runtime_get(cmdq->mbox.dev) < 0); > > +WARN_ON(clk_bulk_enable(cmdq->pdata->gce_num, cmdq->clocks)); > > That's a no... First, you remove error handling. Second, you add WARN > and code should not have WARNs for error handling. It should not use WARNs instead of error return. I'll revert this. > > All this looks like terrible hacky workaround just to make warning go > away, without actually addressing real problem. > I think Angelo's idea is far better, so I'll try to implement the PM function hook to achieve this. Regards, Jason-JH.Lin > Best regards, > Krzysztof > > </pre> </p></body></html><pre>************* MEDIATEK Confidentiality Notice ******************** The information contained in this e-mail message (including any attachments) may be confidential, proprietary, privileged, or otherwise exempt from disclosure under applicable laws. It is intended to be conveyed only to the designated recipient(s). Any use, dissemination, distribution, printing, retaining or copying of this e-mail (including its attachments) by unintended recipient(s) is strictly prohibited and may be unlawful. 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