From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH 2/2] alpha/ptrace: Add missing switch_stack frames
Date: Wed, 16 Jun 2021 20:55:49 +0000
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To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, Michael Schmitz <schmitzmic@gmail.com>, linux-arch <linux-arch@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>, Oleg Nesterov <oleg@redhat.com>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Richard Henderson <rth@twiddle.net>, Ivan Kokshaysky <ink@jurassic.park.msu.ru>, Matt Turner <mattst88@gmail.com>, alpha <linux-alpha@vger.kernel.org>, Geert Uytterhoeven <geert@linux-m68k.org>, linux-m68k <linux-m68k@lists.linux-m68k.org>, Arnd Bergmann <arnd@kernel.org>, Ley Foon Tan <ley.foon.tan@intel.com>, Tejun Heo <tj@kernel.org>, Kees Cook <keescook@chromium.org>

On Wed, Jun 16, 2021 at 03:47:28PM -0500, Eric W. Biederman wrote:

> Fork already saves the registers, all I did was restore them.  Which
> makes a debugger that modifies them in
> PTRACE_EVENT_{FORK,VFORK,CLONE,VFORK_DONE} work.

... first time ever.  Wonderful and well worth the overhead.
</sarcasm>