6.6-stable review patch. If anyone has any objections, please let me know.
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From: Rengarajan S rengarajan.s@microchip.com
commit 18eb77c75ed01439f96ae5c0f33461eb5134b907 upstream.
Resolve kernel panic while accessing IRQ handler associated with the generated IRQ. This is done by acquiring the spinlock and storing the current interrupt state before handling the interrupt request using generic_handle_irq.
A previous fix patch was submitted where 'generic_handle_irq' was replaced with 'handle_nested_irq'. However, this change also causes the kernel panic where after determining which GPIO triggered the interrupt and attempting to call handle_nested_irq with the mapped IRQ number, leads to a failure in locating the registered handler.
Fixes: 194f9f94a516 ("misc: microchip: pci1xxxx: Resolve kernel panic during GPIO IRQ handling") Cc: stable stable@kernel.org Signed-off-by: Rengarajan S rengarajan.s@microchip.com Link: https://lore.kernel.org/r/20250313170856.20868-2-rengarajan.s@microchip.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c +++ b/drivers/misc/mchp_pci1xxxx/mchp_pci1xxxx_gpio.c @@ -37,6 +37,7 @@ struct pci1xxxx_gpio { struct auxiliary_device *aux_dev; void __iomem *reg_base; + raw_spinlock_t wa_lock; struct gpio_chip gpio; spinlock_t lock; int irq_base; @@ -254,6 +255,7 @@ static irqreturn_t pci1xxxx_gpio_irq_han struct pci1xxxx_gpio *priv = dev_id; struct gpio_chip *gc = &priv->gpio; unsigned long int_status = 0; + unsigned long wa_flags; unsigned long flags; u8 pincount; int bit; @@ -277,7 +279,9 @@ static irqreturn_t pci1xxxx_gpio_irq_han writel(BIT(bit), priv->reg_base + INTR_STATUS_OFFSET(gpiobank)); spin_unlock_irqrestore(&priv->lock, flags); irq = irq_find_mapping(gc->irq.domain, (bit + (gpiobank * 32))); - handle_nested_irq(irq); + raw_spin_lock_irqsave(&priv->wa_lock, wa_flags); + generic_handle_irq(irq); + raw_spin_unlock_irqrestore(&priv->wa_lock, wa_flags); } } spin_lock_irqsave(&priv->lock, flags);