From 4de5215f068d068c61c922df799937362005613d Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Fri, 11 Feb 2022 19:14:55 +0100
Subject: [PATCH 160/166] i2c: core: Use generic_handle_irq_safe() in
 i2c_handle_smbus_host_notify().

The i2c-i801 driver invokes i2c_handle_smbus_host_notify() from his
interrupt service routine. On PREEMPT_RT i2c-i801's handler is forced
threaded with enabled interrupts which leads to a warning by
handle_irq_event_percpu() assuming that irq_default_primary_handler()
enabled interrupts.

i2c-i801's interrupt handler can't be made non-threaded because the
interrupt line is shared with other devices.

Use generic_handle_irq_safe() which can invoked with disabled and enabled
interrupts.

Reported-by: Michael Below <below@judiz.de>
Link: https://bugs.debian.org/1002537
Cc: Salvatore Bonaccorso <carnil@debian.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Wolfram Sang <wsa@kernel.org>
Link: https://lore.kernel.org/r/20220211181500.1856198-3-bigeasy@linutronix.de
(cherry picked from commit 7e44f2d97e9c2662134fa50b901a1312c5c1a544)
Signed-off-by: Clark Williams <williams@redhat.com>
---
 drivers/i2c/i2c-core-base.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-5.15.13-rt26/drivers/i2c/i2c-core-base.c
===================================================================
@ linux-5.15.13-rt26/drivers/i2c/i2c-core-base.c:1425 @ int i2c_handle_smbus_host_notify(struct
 	if (irq <= 0)
 		return -ENXIO;
 
-	generic_handle_irq(irq);
+	generic_handle_irq_safe(irq);
 
 	return 0;
 }