Date: Wed, 7 Jun 2017 19:08:58 +0200
From: "Luis R. Rodriguez" <mcgrof@kernel.org>
To: "Fuzzey, Martin" <mfuzzey@parkeon.com>, linux-fsdevel@vger.kernel.org,
        Alan Cox <alan@linux.intel.com>, "Ted Ts'o" <tytso@mit.edu>,
        Andy Lutomirski <luto@kernel.org>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>,
        "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>,
        Linux API <linux-api@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Greg KH <gregkh@linuxfoundation.org>, Daniel Wagner <wagi@monom.org>,
        David Woodhouse <dwmw2@infradead.org>, jewalt@lgsinnovations.com,
        rafal@milecki.pl, Arend Van Spriel <arend.vanspriel@broadcom.com>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        "Li, Yi" <yi1.li@linux.intel.com>, atull@opensource.altera.com,
        Moritz Fischer <moritz.fischer@ettus.com>,
        Petr Mladek <pmladek@suse.com>,
        Johannes Berg <johannes.berg@intel.com>,
        Emmanuel Grumbach <emmanuel.grumbach@intel.com>,
        Luca Coelho <luciano.coelho@intel.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        AKASHI Takahiro <takahiro.akashi@linaro.org>,
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        Hans de Goede <hdegoede@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] firmware: fix sending -ERESTARTSYS due to signal on
 fallback
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On Thu, May 25, 2017 at 10:28:38AM +0200, Fuzzey, Martin wrote:
> 1) Android init calls write() on the sysfs file
> 2) The sysfs .store() callback registered by a driver is called
> 3) The driver calls request_firmware()
> 4) request_firmware() sends the firmware load request to userspace and
> calls wait_for_completion_interruptible()

Martin, just for completeness on documenting on the commit log of the next
swait proposed fix for this -- what signal did the process get from which you
note the child dies below ? Exactly what in Android sent this signal ?

> 5) A child dies and raises SIGCHLD
> 6) wait_for_completion_interruptible() returns -ERESTARTSYS due to the signal

  Luis