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, 29 Nov 2006 09:44:28 +0100
From:	Jarek Poplawski <jarkao2@...pl>
To:	Herbert Xu <herbert@...dor.apana.org.au>
Cc:	davem@...emloft.net, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org, akpm@...l.org, mingo@...e.hu,
	gandalf@...g.westbo.se
Subject: Re: [PATCH] lockdep: fix sk->sk_callback_lock locking

On 29-11-2006 08:49, Herbert Xu wrote:
> Peter Zijlstra <a.p.zijlstra@...llo.nl> wrote:
>> =========================================================
>> [ INFO: possible irq lock inversion dependency detected ]
>> 2.6.19-rc6 #4
>> ---------------------------------------------------------
>> nc/1854 just changed the state of lock:
>> (af_callback_keys + sk->sk_family#2){-.-?}, at: [<c0268a7f>] sock_def_error_report+0x1f/0x90
>> but this lock was taken by another, soft-irq-safe lock in the past:
>> (slock-AF_INET){-+..}
>>
>> and interrupts could create inverse lock ordering between them.
> 
> I think this is bogus.  The slock is not a standard lock.  When we
> hold it in process context we don't actually hold the spin lock part
> of it.  However, it does prevent the softirq path from running in
> critical sections which also prevents any attempt to grab the
> callback lock from softirq context.
> 
> If you still think there is a problem, please show an actual scenario
> where it dead locks.

It would be nice to have a look at other parts of stack
backtraces probably with softirq part, which took that
lock: sk->sk_family#2){-.-?}

Jarek P. 
-
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/

Powered by blists - more mailing lists