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From: Justin Stitt <justinstitt@google.com>
Date: Thu, 9 May 2024 15:04:07 -0700
Message-ID: <CAFhGd8oZy5aKjp-mVhh2d3U3tzTMzVRAfE039gvBACC0AdDNQw@mail.gmail.com>
Subject: Re: [PATCH] tty: vt: saturate scrollback_delta to avoid overflow
To: Jiri Slaby <jirislaby@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Nathan Chancellor <nathan@kernel.org>, 
	Bill Wendling <morbo@google.com>, linux-kernel@vger.kernel.org, 
	linux-serial@vger.kernel.org, llvm@lists.linux.dev
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On Thu, May 9, 2024 at 3:01=E2=80=AFPM Justin Stitt <justinstitt@google.com=
> wrote:
>
>
> Agreed.
>
> Does an implementation like this look any better?
>
> static inline void scrolldelta(int lines)
> {
>         ...
>         /* saturate scrollback_delta so that it never wraps around */
>         if (lines > 0)
>                 scrollback_delta =3D min(scrollback_delta, INT_MAX -
> lines) + lines;
>         else
>                 scrollback_delta =3D max(scrollback_delta, INT_MIN -
> lines) + lines;
>         schedule_console_callback();
> }

I apologize for this formatting, gmail ate my tabs.

Note to self, do NOT copy/paste from vim to gmail's web client.

> Thanks
> Justin