linux-kernel - Re: [PATCH v4 3.0-rc2-tip 14/22] 14: x86: uprobes exception notifier for x86.

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: <1308663167.26237.146.camel@twins>
Date:	Tue, 21 Jun 2011 15:32:47 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
Cc:	Ingo Molnar <mingo@...e.hu>, Steven Rostedt <rostedt@...dmis.org>,
	Linux-mm <linux-mm@...ck.org>,
	Arnaldo Carvalho de Melo <acme@...radead.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
	Hugh Dickins <hughd@...gle.com>,
	Christoph Hellwig <hch@...radead.org>,
	Andi Kleen <andi@...stfloor.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Jonathan Corbet <corbet@....net>,
	Oleg Nesterov <oleg@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Jim Keniston <jkenisto@...ux.vnet.ibm.com>,
	Roland McGrath <roland@...k.frob.com>,
	Ananth N Mavinakayanahalli <ananth@...ibm.com>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v4 3.0-rc2-tip 14/22] 14: x86: uprobes exception
 notifier for x86.

On Tue, 2011-06-21 at 15:31 +0200, Peter Zijlstra wrote:
> On Tue, 2011-06-07 at 18:31 +0530, Srikar Dronamraju wrote:
> > @@ -844,6 +845,19 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
> >         if (thread_info_flags & _TIF_SIGPENDING)
> >                 do_signal(regs);
> >  
> > +       if (thread_info_flags & _TIF_UPROBE) {
> > +               clear_thread_flag(TIF_UPROBE);
> > +#ifdef CONFIG_X86_32
> > +               /*
> > +                * On x86_32, do_notify_resume() gets called with
> > +                * interrupts disabled. Hence enable interrupts if they
> > +                * are still disabled.
> > +                */
> > +               local_irq_enable();
> > +#endif
> > +               uprobe_notify_resume(regs);
> > +       } 
> 
> Would it make sense to do TIF_UPROBE before TIF_SIGPENDING? That way
> when uprobe decides it ought to have send a signal we don't have to do
> another loop through all this.


Also, it might be good to unify x86_86 and i386 on the interrupt thing,
instead of propagating this difference (unless of course there's a good
reason they're different, but I really don't know this code well).
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/