Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CA+55aFydRUyNWz5M2nWWMsLk5dW5JjRRNcFjP62yecAJ_bSDpQ@mail.gmail.com>
Date: Fri, 26 Jan 2018 10:13:38 -0800
From: Linus Torvalds <torvalds@...ux-foundation.org>
To: Al Viro <viro@...iv.linux.org.uk>
Cc: Andy Lutomirski <luto@...nel.org>, Alan Cox <alan@...ux.intel.com>, 
	David Laight <David.Laight@...lab.com>, "the arch/x86 maintainers" <x86@...nel.org>, 
	LKML <linux-kernel@...r.kernel.org>, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Jann Horn <jannh@...gle.com>, 
	Samuel Neves <samuel.c.p.neves@...il.com>, Dan Williams <dan.j.williams@...el.com>, 
	Kernel Hardening <kernel-hardening@...ts.openwall.com>, Borislav Petkov <bp@...en8.de>
Subject: Re: [PATCH] x86/retpoline/entry: Disable the entire SYSCALL64 fast
 path with retpolines on

On Fri, Jan 26, 2018 at 10:07 AM, Al Viro <viro@...iv.linux.org.uk> wrote:
>
> Umm...  What about other architectures?  Or do you want SYSCALL_DEFINE...
> to be per-arch?  I wonder how much would that "go through pt_regs" hurt
> on something like sparc...

No, but I just talked to Will Deacon about register clearing on entry,
and so I suspect that arm64 might want something similar too.

So I think some opt-in for letting architectures add their own
function would be good. Because it wouldn't be all architectures, but
it probably _would_ be more than just x86.

You need to add architecture-specific "load argX from ptregs" macros anyway.

             Linus

Powered by blists - more mailing lists

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.