linux-kernel - Re: qrwlock && read-after-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: <20150804173232.GS25159@twins.programming.kicks-ass.net>
Date:	Tue, 4 Aug 2015 19:32:32 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Oleg Nesterov <oleg@...hat.com>
Cc:	Arnd Bergmann <arnd@...db.de>, Ingo Molnar <mingo@...hat.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	"Paul E.McKenney" <paulmck@...ux.vnet.ibm.com>,
	Waiman Long <Waiman.Long@...com>, linux-kernel@...r.kernel.org
Subject: Re: qrwlock && read-after-read

On Tue, Aug 04, 2015 at 03:40:43PM +0200, Oleg Nesterov wrote:
> Lets fix the lockdep annotaions?
> 
> Oleg.
> 
> --- x/include/linux/rwlock_api_smp.h
> +++ x/include/linux/rwlock_api_smp.h
> @@ -146,7 +146,7 @@ static inline int __raw_write_trylock(rw
>  static inline void __raw_read_lock(rwlock_t *lock)
>  {
>  	preempt_disable();
> -	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
> +	lock_acquire(..., /* read */ in_interrupt() 2 : 1, ...);
>  	LOCK_CONTENDED(lock, do_raw_read_trylock, do_raw_read_lock);
>  }

I think that suffers the same problems we had before; see:

  8acd91e86208 ("locking/lockdep: Revert qrwlock recusive stuff")
--
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/