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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 10 Jan 2024 16:32:57 -0800
Message-ID: <CAHk-=wjdW-4s6Kpa4izJ2D=yPdCje6Ta=eQxxQG6e2SkP42vnw@mail.gmail.com>
Subject: Re: [PATCH v4 5/6] add listmount(2) syscall
To: Guenter Roeck <linux@roeck-us.net>
Cc: Miklos Szeredi <mszeredi@redhat.com>, linux-fsdevel@vger.kernel.org, 
	linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, 
	linux-man@vger.kernel.org, linux-security-module@vger.kernel.org, 
	Karel Zak <kzak@redhat.com>, Ian Kent <raven@themaw.net>, David Howells <dhowells@redhat.com>, 
	Al Viro <viro@zeniv.linux.org.uk>, Christian Brauner <christian@brauner.io>, 
	Amir Goldstein <amir73il@gmail.com>, Matthew House <mattlloydhouse@gmail.com>, 
	Florian Weimer <fweimer@redhat.com>, Arnd Bergmann <arnd@arndb.de>
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On Wed, 10 Jan 2024 at 14:23, Guenter Roeck <linux@roeck-us.net> wrote:
>
> with this patch in the tree, all sh4 builds fail with ICE.
>
> during RTL pass: final
> In file included from fs/namespace.c:11:
> fs/namespace.c: In function '__se_sys_listmount':
> include/linux/syscalls.h:258:9: internal compiler error: in change_address_1, at emit-rtl.c:2275

We do have those very ugly SYSCALL_DEFINEx() macros, but I'm not
seeing _anything_ that would be odd about the listmount case.

And the "__se_sys" thing in particular is just a fairly trivial wrapper.

It does use that asmlinkage_protect() thing, and it is unquestionably
horrendously ugly (staring too long at <linux/syscalls.h> has been
known to cause madness and despair), but we do that for *every* single
system call and I don't see why the new listmount entry would be
different.

           Linus