linux-kernel - Re: [PATCH] firwmare: Correct handling of fw_state

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Date:   Thu, 8 Dec 2016 16:28:18 +0100
From:   "Luis R. Rodriguez" <mcgrof@...nel.org>
To:     Daniel Wagner <daniel.wagner@...-carit.de>
Cc:     Bjorn Andersson <bjorn.andersson@...aro.org>,
        Ming Lei <ming.lei@...onical.com>,
        "Luis R. Rodriguez" <mcgrof@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-kernel@...r.kernel.org, linux-remoteproc@...r.kernel.org
Subject: Re: [PATCH] firwmare: Correct handling of fw_state_wait() return
 value

On Thu, Dec 08, 2016 at 03:47:22PM +0100, Daniel Wagner wrote:
> On 12/07/2016 02:01 AM, Bjorn Andersson wrote:
> > When request_firmware() finds an already open firmware object it will
> > wait for that object to become fully loaded and then check the status.
> > As __fw_state_wait_common() succeeds the timeout value returned will be
> > truncated in _request_firmware_prepare() and interpreted as -EPERM.
> > 
> > Prior to "firmware: do not use fw_lock for fw_state protection" the code
> > did test if we where in the "done" state before sleeping, causing this
> > particular code path to succeed, in some cases.
> > 
> > As the callers are interested in the result of the wait and not the
> > remaining timeout the return value of __fw_state_wait_common() is
> > changed to signal "done" or "error", which simplifies the logic in
> > _request_firmware_load() as well.
> 
> Oops, sorry about that one. With your fix the code starts to make sense.
> 
> > Fixes: 5b029624948d ("firmware: do not use fw_lock for fw_state protection")
> > Signed-off-by: Bjorn Andersson <bjorn.andersson@...aro.org>
> 
> Reviewed-by: Daniel Wagner <daniel.wagner@...-carit.de>

Acked-by: Luis R. Rodriguez <mcgrof@...nel.org>

  Luis