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Date:   Thu, 4 Nov 2021 13:07:52 +0000 (GMT)
From:   "Maciej W. Rozycki" <macro@orcam.me.uk>
To:     Andrzej Pietrasiewicz <andrzej.p@collabora.com>
cc:     Pavel Machek <pavel@ucw.cz>, linux-kernel@vger.kernel.org,
        linux-input@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Jiri Slaby <jirislaby@kernel.org>, kernel@collabora.com
Subject: Re: [RFC] tty/sysrq: Add alternative SysRq key
In-Reply-To: <17ccc35d-441c-70c1-a80a-28a4ff824535@collabora.com>
Message-ID: <alpine.DEB.2.21.2111041227510.57165@angie.orcam.me.uk>
References: <20211103155438.11167-1-andrzej.p@collabora.com> <20211104120111.GB23122@duo.ucw.cz> <17ccc35d-441c-70c1-a80a-28a4ff824535@collabora.com>
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On Thu, 4 Nov 2021, Andrzej Pietrasiewicz wrote:

> > Is F10 sensible default? Would it make sense to use something like
> > alt-shift-esc so that this can be enabled by default?
> 
> Why "alt-shift-esc" could be enabled by default? Do you mean to enable it for
> all systems regardless of whether they declare or don't declare KEY_SYSRQ
> in their 'keybit' bitmap?

 FWIW from my perspective it'll work better as a replacement rather than 
additional key combination.

 The reason for this is with their more recent laptops Lenovo in their 
infinite wisdom have placed the <PrintScreen> key (which in a traditional 
PS/2-keyboard manner produces <SysRq> when combined with <Alt>) in their 
keyboards between the right <Alt> and <Ctrl> keys.  With thumbs not being 
as accurate as other fingers (and the overall misdesign of the keyboard 
and touchpad interface) you can imagine how often I have inadvertently hit 
<SysRq> combined with a letter key, wreaking havoc to my system (and of 
course I want to keep the key enabled for times when I do need it).

 Also Documentation/admin-guide/sysrq.rst mentions that you can set an 
alternative keycode sequence for KEY_SYSRQ with `setkeycodes <sequence> 
99' already, but I find this pretty limiting as this only works for single 
keypresses rather than combinations of keys, because <sequence> actually 
refers to a single scancode (possibly 0xe0-prefixed).

  Maciej