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Subject: Re: [PATCH 3/3] firmware: add mutex fw_lock_fallback for race
 condition
To:     Luis Chamberlain <mcgrof@kernel.org>, Takashi Iwai <tiwai@suse.de>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andy Gross <andy.gross@linaro.org>,
        David Brown <david.brown@linaro.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Shuah Khan <shuah@kernel.org>, bjorn.andersson@linaro.org,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-fsdevel@vger.kernel.org,
        BCM Kernel Feedback <bcm-kernel-feedback-list@broadcom.com>,
        Olof Johansson <olof@lixom.net>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Colin Ian King <colin.king@canonical.com>,
        Kees Cook <keescook@chromium.org>,
        linux-kselftest@vger.kernel.org
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From:   Scott Branden <scott.branden@broadcom.com>
Message-ID: <95736fe7-31e1-ab6e-11f6-e209951402a9@broadcom.com>
Date:   Fri, 23 Aug 2019 12:56:47 -0700
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On 2019-08-23 8:43 a.m., Luis Chamberlain wrote:
> On Fri, Aug 23, 2019 at 12:31:40PM +0200, Takashi Iwai wrote:
>> So, if any, we'd need put a mutex around the fallback loader code.
>> And, the mutex should be rather per device, not a global one.
>>
>> Or we may trick it by appending the second parallel caller into the
>> same wait queue, but the code will be more complex, so I don't think
>> worth for it.
> For now I'm thinking of a new API with a devname prefix to the driver.
> I'll have to test if that works, but not sure if I'll get to it today
> before my vacation starts (today).
Have a good vacation.
>
>    Luis