Date: Wed, 7 Jun 2017 19:15:07 +0200
From: "Luis R. Rodriguez" <mcgrof@kernel.org>
To: Alan Cox <alan@linux.intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Andy Lutomirski <luto@kernel.org>,
        "Luis R. Rodriguez" <mcgrof@kernel.org>,
        "Theodore Ts'o" <tytso@mit.edu>,
        Linux FS Devel <linux-fsdevel@vger.kernel.org>,
        Stephen Boyd <stephen.boyd@linaro.org>,
        "Li, Yi" <yi1.li@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Jonathan Corbet <corbet@lwn.net>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        "Fuzzey, Martin" <mfuzzey@parkeon.com>,
        Linux API <linux-api@vger.kernel.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>,
        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>,
        Kees Cook <keescook@chromium.org>,
        AKASHI Takahiro <takahiro.akashi@linaro.org>,
        David Howells <dhowells@redhat.com>, Peter Jones <pjones@redhat.com>,
        Hans de G oede <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 Wed, Jun 07, 2017 at 01:25:51PM +0100, Alan Cox wrote:
> > What's wrong with saying that the only way to interrupt firmware
> > loading is to kill the process? So ctrl-c will no longer interrupt
> > it, but I do not think that ease of aborting firmware update is
> > primary goal here. I consider simple is good here.
> 
> Agreed 100%. The user process did not ask for firmware load, it asked
> for an I/O operation. Semantically it should appear as if someone else
> did the firmware load and it just had to wait for it to happen.

Fine by me ! Will wrap up the patch for the new killable swait then.
I suppose noting it as a stable fix is worth it given the known issues
with for example Android killing loaders unexpectedly.

Unless I hear otherwise I'll also provide a follow up to return -EINTR instead
of -EAGAIN if swait returned -ERESTARTSYS, this way at least userspace could
tell a signal was definitely received. I *don't* think that follow up is
required for stable though.

  Luis