linux-kernel - [PATCH v2 4/4] irqchip: bcm2836: Use a more generic memory barrier call

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] [day] [month] [year] [list]

Message-Id: <1460579323-8099-4-git-send-email-eric@anholt.net>
Date:	Wed, 13 Apr 2016 13:28:43 -0700
From:	Eric Anholt <eric@...olt.net>
To:	linux-rpi-kernel@...ts.infradead.org
Cc:	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	Stephen Warren <swarren@...dotorg.org>,
	Lee Jones <lee@...nel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Jason Cooper <jason@...edaemon.net>,
	Marc Zyngier <marc.zyngier@....com>,
	Eric Anholt <eric@...olt.net>
Subject: [PATCH v2 4/4] irqchip: bcm2836: Use a more generic memory barrier call

dsb() requires an argument on arm64, so we needed to add "sy".
Instead, take this opportunity to switch to the same smp_wmb() call
that gic uses for its IPIs.  This is a less strong barrier than we
were doing before (dmb(ishst) compared to dsb(sy)), but it seems to be
the correct one.

Signed-off-by: Eric Anholt <eric@...olt.net>
Acked-by: Stephen Warren <swarren@...dotorg.org>
---

v2: add ack

 drivers/irqchip/irq-bcm2836.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c
index bb3d61fe4bdb..27875982657e 100644
--- a/drivers/irqchip/irq-bcm2836.c
+++ b/drivers/irqchip/irq-bcm2836.c
@@ -195,7 +195,7 @@ static void bcm2836_arm_irqchip_send_ipi(const struct cpumask *mask,
 	 * Ensure that stores to normal memory are visible to the
 	 * other CPUs before issuing the IPI.
 	 */
-	dsb();
+	smp_wmb();
 
 	for_each_cpu(cpu, mask)	{
 		writel(1 << ipi, mailbox0_base + 16 * cpu);
-- 
2.8.0.rc3