linux-kernel - Re: [PATCH] time/sched_clock: mark sched_clock_read

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: <20200929071333.GK2628@hirez.programming.kicks-ass.net>
Date:   Tue, 29 Sep 2020 09:13:33 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Steven Rostedt <rostedt@...dmis.org>
Cc:     quanyang.wang@...driver.com, linux-kernel@...r.kernel.org,
        Thomas Gleixner <tglx@...utronix.de>,
        Leo Yan <leo.yan@...aro.org>, Will Deacon <will@...nel.org>,
        a.darwish@...utronix.de,
        Daniel Lezcano <daniel.lezcano@...aro.org>,
        Paul Cercueil <paul@...pouillou.net>,
        Randy Dunlap <rdunlap@...radead.org>, ben.dooks@...ethink.co.uk
Subject: Re: [PATCH] time/sched_clock: mark sched_clock_read_begin as notrace

On Mon, Sep 28, 2020 at 05:33:31PM -0400, Steven Rostedt wrote:
> On Mon, 28 Sep 2020 12:58:59 +0200
> Peter Zijlstra <peterz@...radead.org> wrote:
> 
> > > -struct clock_read_data *sched_clock_read_begin(unsigned int *seq)
> > > +notrace struct clock_read_data *sched_clock_read_begin(unsigned int *seq)
> > >  {
> > >  	*seq = raw_read_seqcount_latch(&cd.seq);
> > >  	return cd.read_data + (*seq & 1);  
> > 
> > At the very least sched_clock_read_retry() should also be marked such.
> > 
> > But Steve, how come x86 works? Our sched_clock() doesn't have notrace on
> > at all.
> 
> It's because of that magic in the Makefile that you love so much ;-)
> 
> CFLAGS_REMOVE_tsc.o = -pg

ARGH!!, I really should write a script to fix up that mess :/