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From:   =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= 
        <noltari@gmail.com>
To:     jonas.gorski@gmail.com, Florian Fainelli <f.fainelli@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Marc Zyngier <maz@kernel.org>,
        bcm-kernel-feedback-list@broadcom.com, linux-mips@vger.kernel.org,
        linux-kernel@vger.kernel.org
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        <noltari@gmail.com>
Subject: [PATCH] irqchip/bcm-6345-l1: fix SMP support
Date:   Mon, 22 Feb 2021 21:13:32 +0100
Message-Id: <20210222201332.30253-1-noltari@gmail.com>
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Some BCM6358 devices start with Core #1 instead of Core #0.
Apart from that, SMP is restricted to 1 CPU since BCM6358 has a shared TLB,
which makes it impossible for the current SMP support to start both CPUs.

The problem is that smp_processor_id() returns 0 and then cpu_logical_map()
converts that to 1, which accesses an uninitialized position of intc->cpus[],
resulting in a kernel panic.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---
 drivers/irqchip/irq-bcm6345-l1.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-bcm6345-l1.c b/drivers/irqchip/irq-bcm6345-l1.c
index e3483789f4df..b2173ce4743d 100644
--- a/drivers/irqchip/irq-bcm6345-l1.c
+++ b/drivers/irqchip/irq-bcm6345-l1.c
@@ -121,7 +121,7 @@ static void bcm6345_l1_irq_handle(struct irq_desc *desc)
 	unsigned int idx;
 
 #ifdef CONFIG_SMP
-	cpu = intc->cpus[cpu_logical_map(smp_processor_id())];
+	cpu = intc->cpus[smp_processor_id()];
 #else
 	cpu = intc->cpus[0];
 #endif
-- 
2.20.1