From 33b1c47d1fc0b5f06a393bb915db85baacba18ea Mon Sep 17 00:00:00 2001 From: Shenwei Wang Date: Wed, 3 Jul 2024 11:32:50 -0500 Subject: [PATCH] irqchip/imx-irqsteer: Handle runtime power management correctly The power domain is automatically activated from clk_prepare(). However, on certain platforms like i.MX8QM and i.MX8QXP, the power-on handling invokes sleeping functions, which triggers the 'scheduling while atomic' bug in the context switch path during device probing: BUG: scheduling while atomic: kworker/u13:1/48/0x00000002 Call trace: __schedule_bug+0x54/0x6c __schedule+0x7f0/0xa94 schedule+0x5c/0xc4 schedule_preempt_disabled+0x24/0x40 __mutex_lock.constprop.0+0x2c0/0x540 __mutex_lock_slowpath+0x14/0x20 mutex_lock+0x48/0x54 clk_prepare_lock+0x44/0xa0 clk_prepare+0x20/0x44 imx_irqsteer_resume+0x28/0xe0 pm_generic_runtime_resume+0x2c/0x44 __genpd_runtime_resume+0x30/0x80 genpd_runtime_resume+0xc8/0x2c0 __rpm_callback+0x48/0x1d8 rpm_callback+0x6c/0x78 rpm_resume+0x490/0x6b4 __pm_runtime_resume+0x50/0x94 irq_chip_pm_get+0x2c/0xa0 __irq_do_set_handler+0x178/0x24c irq_set_chained_handler_and_data+0x60/0xa4 mxc_gpio_probe+0x160/0x4b0 Cure this by implementing the irq_bus_lock/sync_unlock() interrupt chip callbacks and handle power management in them as they are invoked from non-atomic context. [ tglx: Rewrote change log, added Fixes tag ] Fixes: 0136afa08967 ("irqchip: Add driver for imx-irqsteer controller") Signed-off-by: Shenwei Wang Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240703163250.47887-1-shenwei.wang@nxp.com --- drivers/irqchip/irq-imx-irqsteer.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/drivers/irqchip/irq-imx-irqsteer.c b/drivers/irqchip/irq-imx-irqsteer.c index 20cf7a9e9ece..75a0e980ff35 100644 --- a/drivers/irqchip/irq-imx-irqsteer.c +++ b/drivers/irqchip/irq-imx-irqsteer.c @@ -36,6 +36,7 @@ struct irqsteer_data { int channel; struct irq_domain *domain; u32 *saved_reg; + struct device *dev; }; static int imx_irqsteer_get_reg_index(struct irqsteer_data *data, @@ -72,10 +73,26 @@ static void imx_irqsteer_irq_mask(struct irq_data *d) raw_spin_unlock_irqrestore(&data->lock, flags); } +static void imx_irqsteer_irq_bus_lock(struct irq_data *d) +{ + struct irqsteer_data *data = d->chip_data; + + pm_runtime_get_sync(data->dev); +} + +static void imx_irqsteer_irq_bus_sync_unlock(struct irq_data *d) +{ + struct irqsteer_data *data = d->chip_data; + + pm_runtime_put_autosuspend(data->dev); +} + static const struct irq_chip imx_irqsteer_irq_chip = { - .name = "irqsteer", - .irq_mask = imx_irqsteer_irq_mask, - .irq_unmask = imx_irqsteer_irq_unmask, + .name = "irqsteer", + .irq_mask = imx_irqsteer_irq_mask, + .irq_unmask = imx_irqsteer_irq_unmask, + .irq_bus_lock = imx_irqsteer_irq_bus_lock, + .irq_bus_sync_unlock = imx_irqsteer_irq_bus_sync_unlock, }; static int imx_irqsteer_irq_map(struct irq_domain *h, unsigned int irq, @@ -150,6 +167,7 @@ static int imx_irqsteer_probe(struct platform_device *pdev) if (!data) return -ENOMEM; + data->dev = &pdev->dev; data->regs = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(data->regs)) { dev_err(&pdev->dev, "failed to initialize reg\n");