linux-kernel - Re: [PATCH] kasan: convert kasan/quarantine_lock to raw

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]

Date:   Wed, 10 Oct 2018 11:53:43 +0200
From:   Sebastian Andrzej Siewior <bigeasy@...utronix.de>
To:     Dmitry Vyukov <dvyukov@...gle.com>
Cc:     Clark Williams <williams@...hat.com>,
        Alexander Potapenko <glider@...gle.com>,
        kasan-dev <kasan-dev@...glegroups.com>,
        Linux-MM <linux-mm@...ck.org>,
        LKML <linux-kernel@...r.kernel.org>,
        linux-rt-users@...r.kernel.org,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH] kasan: convert kasan/quarantine_lock to raw_spinlock

On 2018-10-10 11:45:32 [+0200], Dmitry Vyukov wrote:
> > Should I repost Clark's patch?
> 
> 
> I am much more comfortable with just changing the type of the lock.

Yes, that is what Clark's patch does. Should I resent it?

> What are the bad implications of using the raw spinlock? Will it help
> to do something along the following lines:
> 
> // Because of ...
> #if CONFIG_RT
> #define quarantine_spinlock_t raw_spinlock_t
> #else
> #define quarantine_spinlock_t spinlock_t
> #endif

no. For !RT spinlock_t and raw_spinlock_t are the same. For RT
spinlock_t does not disable interrupts or preemption while
raw_spinlock_t does.
Therefore holding a raw_spinlock_t might increase your latency.

Sebastian