linux-kernel - RE: [patch V2 2/5] posix-cpu-timers: Convert the flags to a bitmap

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 for Android: free password hash cracker in your pocket

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

Date:   Tue, 21 Jul 2020 16:23:01 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     'Thomas Gleixner' <tglx@...utronix.de>,
        Frederic Weisbecker <frederic@...nel.org>
CC:     LKML <linux-kernel@...r.kernel.org>,
        "x86@...nel.org" <x86@...nel.org>, Oleg Nesterov <oleg@...hat.com>,
        "Eric W. Biederman" <ebiederm@...ssion.com>,
        John Stultz <john.stultz@...aro.org>,
        Paolo Bonzini <pbonzini@...hat.com>
Subject: RE: [patch V2 2/5] posix-cpu-timers: Convert the flags to a bitmap

From: Thomas Gleixner
> Sent: 21 July 2020 17:11
> 
> Frederic Weisbecker <frederic@...nel.org> writes:
> > On Thu, Jul 16, 2020 at 10:19:25PM +0200, Thomas Gleixner wrote:
> >> --- a/kernel/time/posix-cpu-timers.c
> >> +++ b/kernel/time/posix-cpu-timers.c
> >> @@ -25,7 +25,7 @@ void posix_cputimers_group_init(struct p
> >>  	posix_cputimers_init(pct);
> >>  	if (cpu_limit != RLIM_INFINITY) {
> >>  		pct->bases[CPUCLOCK_PROF].nextevt = cpu_limit * NSEC_PER_SEC;
> >> -		pct->timers_active = true;
> >> +		set_bit(CPUTIMERS_ACTIVE, &pct->flags);
> >
> > I guess this one could be __set_bit().
> 
> True :)

Hmmm... does this code need the bit operations to be atmomic?
If not then an bitmap is completely the wrong thing to be using.

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)