linux-kernel - Re: [PATCH 6/7] of/platform: Skip coresight etm4x devices from AMBA bus

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]

Message-ID: <6ac7d093-b11c-b37f-8058-72c8d41fba73@arm.com>
Date:   Mon, 20 Mar 2023 11:07:51 +0530
From:   Anshuman Khandual <anshuman.khandual@....com>
To:     Suzuki K Poulose <suzuki.poulose@....com>,
        Rob Herring <robh+dt@...nel.org>
Cc:     linux-arm-kernel@...ts.infradead.org, coresight@...ts.linaro.org,
        scclevenger@...amperecomputing.com,
        Frank Rowand <frowand.list@...il.com>,
        Russell King <linux@...linux.org.uk>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Len Brown <lenb@...nel.org>,
        Sudeep Holla <sudeep.holla@....com>,
        Lorenzo Pieralisi <lpieralisi@...nel.org>,
        Mathieu Poirier <mathieu.poirier@...aro.org>,
        Mike Leach <mike.leach@...aro.org>,
        Leo Yan <leo.yan@...aro.org>, devicetree@...r.kernel.org,
        linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 6/7] of/platform: Skip coresight etm4x devices from AMBA
 bus



On 3/17/23 21:33, Suzuki K Poulose wrote:
>>>   drivers/of/platform.c | 10 +++++++++-
>>>   1 file changed, 9 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
>>> index b2bd2e783445..59ff1a38ccaa 100644
>>> --- a/drivers/of/platform.c
>>> +++ b/drivers/of/platform.c
>>> @@ -325,6 +325,13 @@ static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *l
>>>          return NULL;
>>>   }
>>>
>>> +static const struct of_device_id of_ignore_amba_table[] = {
>>> +#ifdef CONFIG_CORESIGHT_SOURCE_ETM4X
>>> +       { .compatible = "arm,coresight-etm4x" },
>>> +#endif
>>> +       {}    /* NULL terminated */
>>> +};
>>> +
>>>   /**
>>>    * of_platform_bus_create() - Create a device for a node and its children.
>>>    * @bus: device node of the bus to instantiate
>>> @@ -373,7 +380,8 @@ static int of_platform_bus_create(struct device_node *bus,
>>>                  platform_data = auxdata->platform_data;
>>>          }
>>>
>>> -       if (of_device_is_compatible(bus, "arm,primecell")) {
>>> +       if (of_device_is_compatible(bus, "arm,primecell") &&
>>> +           unlikely(!of_match_node(of_ignore_amba_table, bus))) {
>>
>> of_match_node is going to take orders of magnitude longer than any
>> difference unlikely() would make. Drop it.
> 
> Agreed.

Sure, will drop the unlikely() here.