linux-kernel - Re: [RFC][PATCH] tracing/x86: Save CR2 before tracing irqsoff on error

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHk-=whSeiDXVvhie_bBPqDw99JNJMdTuX8ef82BhNanyo7zRw@mail.gmail.com>
Date:   Thu, 21 Mar 2019 11:18:53 -0700
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     Andy Lutomirski <luto@...capital.net>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Juergen Gross <jgross@...e.com>,
        LKML <linux-kernel@...r.kernel.org>,
        "H. Peter Anvin" <hpa@...or.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...nel.org>, Borislav Petkov <bp@...en8.de>,
        Joel Fernandes <joel@...lfernandes.org>,
        He Zhe <zhe.he@...driver.com>
Subject: Re: [RFC][PATCH] tracing/x86: Save CR2 before tracing irqsoff on error_entry

On Thu, Mar 21, 2019 at 11:05 AM Andy Lutomirski <luto@...capital.net> wrote:
>
> In the long run, I think the right solution is to rewrite even more of
> this mess in C.  We really ought to be able to put the IRQ flag
> tracing and the context tracking into C code.

Tangentially about this long run thing - can we start discussing just
dropping PV mode entirely in the long run? Or even not-so-long run?

What are the pressing advantages of paravirt these days? Because I can
point to a lot of pressing _disadvantages_, and not all of them are
about more complex code as shown by this patch...

             Linus