[4.2.y-ckt stable] Patch "ACPI: Use correct IRQ when uninstalling ACPI interrupt handler" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    ACPI: Use correct IRQ when uninstalling ACPI interrupt handler

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt1.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 7600d613d9e790ae22f2f55aa64cf70d74844c81 Mon Sep 17 00:00:00 2001
From: Chen Yu <yu.c.chen at intel.com>
Date: Sun, 25 Oct 2015 01:02:19 +0800
Subject: ACPI: Use correct IRQ when uninstalling ACPI interrupt handler

commit 49e4b84333f338d4f183f28f1f3c1131b9fb2b5a upstream.

Currently when the system is trying to uninstall the ACPI interrupt
handler, it uses acpi_gbl_FADT.sci_interrupt as the IRQ number.
However, the IRQ number that the ACPI interrupt handled is installed
for comes from acpi_gsi_to_irq() and that is the number that should
be used for the handler removal.

Fix this problem by using the mapped IRQ returned from acpi_gsi_to_irq()
as appropriate.

Acked-by: Lv Zheng <lv.zheng at intel.com>
Signed-off-by: Chen Yu <yu.c.chen at intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/acpi/osl.c   | 9 ++++++---
 include/linux/acpi.h | 6 ++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 3b8963f..9323096 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -83,6 +83,7 @@ static void *acpi_irq_context;
 static struct workqueue_struct *kacpid_wq;
 static struct workqueue_struct *kacpi_notify_wq;
 static struct workqueue_struct *kacpi_hotplug_wq;
+unsigned int acpi_sci_irq = INVALID_ACPI_IRQ;

 /*
  * This list of permanent mappings is for memory that may be accessed from
@@ -858,17 +859,19 @@ acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
 		acpi_irq_handler = NULL;
 		return AE_NOT_ACQUIRED;
 	}
+	acpi_sci_irq = irq;

 	return AE_OK;
 }

-acpi_status acpi_os_remove_interrupt_handler(u32 irq, acpi_osd_handler handler)
+acpi_status acpi_os_remove_interrupt_handler(u32 gsi, acpi_osd_handler handler)
 {
-	if (irq != acpi_gbl_FADT.sci_interrupt)
+	if (gsi != acpi_gbl_FADT.sci_interrupt || !acpi_sci_irq_valid())
 		return AE_BAD_PARAMETER;

-	free_irq(irq, acpi_irq);
+	free_irq(acpi_sci_irq, acpi_irq);
 	acpi_irq_handler = NULL;
+	acpi_sci_irq = INVALID_ACPI_IRQ;

 	return AE_OK;
 }
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 0b2394f..b92ec06 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -197,6 +197,12 @@ int acpi_ioapic_registered(acpi_handle handle, u32 gsi_base);
 void acpi_irq_stats_init(void);
 extern u32 acpi_irq_handled;
 extern u32 acpi_irq_not_handled;
+extern unsigned int acpi_sci_irq;
+#define INVALID_ACPI_IRQ	((unsigned)-1)
+static inline bool acpi_sci_irq_valid(void)
+{
+	return acpi_sci_irq != INVALID_ACPI_IRQ;
+}

 extern int sbf_port;
 extern unsigned long acpi_realmode_flags;
--
1.9.1