• Shenwei Wang's avatar
    irqchip/imx-irqsteer: Handle runtime power management correctly · 33b1c47d
    Shenwei Wang authored
    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: 0136afa0 ("irqchip: Add driver for imx-irqsteer controller")
    Signed-off-by: default avatarShenwei Wang <shenwei.wang@nxp.com>
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Cc: stable@vger.kernel.org
    Link: https://lore.kernel.org/r/20240703163250.47887-1-shenwei.wang@nxp.com
    33b1c47d
irq-imx-irqsteer.c 8.15 KB