linux-kernel - [RFC PATCH 6/9] ACPI / gsi: Add gsi_mutex to synchronize acpi_register_gsi()/acpi_unregister

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue,  5 May 2015 21:50:54 +0800
From:	Hanjun Guo <hanjun.guo@...aro.org>
To:	Marc Zyngier <marc.zyngier@....com>,
	Jason Cooper <jason@...edaemon.net>,
	Will Deacon <will.deacon@....com>,
	Catalin Marinas <catalin.marinas@....com>,
	"Rafael J. Wysocki" <rjw@...ysocki.net>
Cc:	Jiang Liu <jiang.liu@...ux.intel.com>,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@....com>,
	Arnd Bergmann <arnd@...db.de>,
	Tomasz Nowicki <tomasz.nowicki@...aro.org>,
	Grant Likely <grant.likely@...aro.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Olof Johansson <olof@...om.net>,
	linux-arm-kernel@...ts.infradead.org, linux-acpi@...r.kernel.org,
	linux-kernel@...r.kernel.org, linaro-acpi@...ts.linaro.org,
	Hanjun Guo <hanjun.guo@...aro.org>
Subject: [RFC PATCH 6/9] ACPI / gsi: Add gsi_mutex to synchronize acpi_register_gsi()/acpi_unregister_gsi()

Add a mutex for acpi_register_gsi()/acpi_unregister_gsi() to avoid
concurrency issues.

Signed-off-by: Hanjun Guo <hanjun.guo@...aro.org>
---
 drivers/acpi/gsi.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/acpi/gsi.c b/drivers/acpi/gsi.c
index f4110d8..f0f219c 100644
--- a/drivers/acpi/gsi.c
+++ b/drivers/acpi/gsi.c
@@ -14,6 +14,7 @@
 
 enum acpi_irq_model_id acpi_irq_model;
 struct irq_domain *acpi_irq_domain;
+static DEFINE_MUTEX(gsi_mutex);
 
 static unsigned int acpi_gsi_get_irq_type(int trigger, int polarity)
 {
@@ -71,20 +72,24 @@ int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
 	int irq;
 	unsigned int irq_type = acpi_gsi_get_irq_type(trigger, polarity);
 
+	mutex_lock(&gsi_mutex);
 	irq = irq_find_mapping(acpi_irq_domain, gsi);
 	if (irq > 0)
-		return irq;
+		goto out;
 
 	irq = irq_domain_alloc_irqs(acpi_irq_domain, 1, dev_to_node(dev),
 				    &gsi);
 	if (irq <= 0)
-		return -EINVAL;
+		goto out;
 
 	/* Set irq type if specified and different than the current one */
 	if (irq_type != IRQ_TYPE_NONE &&
 		irq_type != irq_get_trigger_type(irq))
 		irq_set_irq_type(irq, irq_type);
-	return irq;
+
+out:
+	mutex_unlock(&gsi_mutex);
+	return irq > 0 ? irq : -EINVAL;
 }
 EXPORT_SYMBOL_GPL(acpi_register_gsi);
 
@@ -94,8 +99,12 @@ EXPORT_SYMBOL_GPL(acpi_register_gsi);
  */
 void acpi_unregister_gsi(u32 gsi)
 {
-	int irq = irq_find_mapping(acpi_irq_domain, gsi);
+	int irq;
+
+	mutex_lock(&gsi_mutex);
+	irq = irq_find_mapping(acpi_irq_domain, gsi);
 
 	irq_dispose_mapping(irq);
+	mutex_unlock(&gsi_mutex);
 }
 EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/