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 for <linuxppc-dev@lists.ozlabs.org> from <aneesh.kumar@linux.vnet.ibm.com>;
 Mon, 30 May 2016 21:29:09 -0600
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
To: Michael Ellerman <mpe@ellerman.id.au>, Anton Blanchard <anton@ozlabs.org>,
 benh@kernel.crashing.org, paulus@samba.org, acsawdey@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH 3/3] powerpc: Avoid load hit store when using
 find_linux_pte_or_hugepte()
In-Reply-To: <1464650992.16938.8.camel@ellerman.id.au>
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 <1464650992.16938.8.camel@ellerman.id.au>
Date: Tue, 31 May 2016 08:59:01 +0530
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Michael Ellerman <mpe@ellerman.id.au> writes:

> On Sun, 2016-05-29 at 22:03 +1000, Anton Blanchard wrote:
>
>> From: Anton Blanchard <anton@samba.org>
>> 
>> In many cases we disable interrupts right before calling
>> find_linux_pte_or_hugepte().
>> 
>> find_linux_pte_or_hugepte() first checks interrupts are disabled
>> before calling __find_linux_pte_or_hugepte():
>> 
>>         if (!arch_irqs_disabled()) {
>>                 pr_info("%s called with irq enabled\n", __func__);
>>                 dump_stack();
>>         }
>
> Should that be a VM_WARN_ON()?
>

VM_WARN_ON() put them inside CONFIG_DEBUG_VM. We should be able to use
WARN(!arch_irqs_disabled(), "%s called with irq enabled\n", __func__);

-aneesh