netdev - Re: [PATCH net] dcbnl : Fix lock initialization

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:	Thu, 06 Nov 2014 12:16:32 -0800
From:	John Fastabend <john.fastabend@...il.com>
To:	Anish Bhatt <anish@...lsio.com>
CC:	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"davem@...emloft.net" <davem@...emloft.net>,
	"john.r.fastabend@...el.com" <john.r.fastabend@...el.com>,
	"ying.xue@...driver.com" <ying.xue@...driver.com>,
	"jeffrey.t.kirsher@...el.com" <jeffrey.t.kirsher@...el.com>,
	"ebiederm@...ssion.com" <ebiederm@...ssion.com>
Subject: Re: [PATCH net] dcbnl : Fix lock initialization

On 11/06/2014 11:12 AM, Anish Bhatt wrote:
> Yes, without this kernel is complaining about inconsitent lock state
> when lock debugging is enabled. Unfortunately I do not have the trace
> lying around right now.
>

If you have the trace that might help. I can't recall seeing any splats
in these code paths. Also as far as I can tell you shouldn't need to do
an init after the define. There are lots of examples in ./net/core where
this is done.

So we need to sort out why the init resolves the issue.

> If you wish, you can reject this patch, I'll resend it when I get the trace again, with trace included.
> -Anish
> ________________________________________
> From: John Fastabend [john.fastabend@...il.com]
> Sent: Thursday, November 06, 2014 11:03 AM
> To: Anish Bhatt
> Cc: netdev@...r.kernel.org; davem@...emloft.net; john.r.fastabend@...el.com; ying.xue@...driver.com; jeffrey.t.kirsher@...el.com; ebiederm@...ssion.com
> Subject: Re: [PATCH net] dcbnl : Fix lock initialization
>
> On 11/06/2014 10:09 AM, Anish Bhatt wrote:
>> dcb_lock was being used uninitialized in dcbnl and is infact missing
>>    initialization code. Fixed
>>
>
> Are you trying to resolve a bug? It is initialized with
>
> static DEFINE_SPINLOCK(dcb_lock);
>
> and if you follow the code far enough you get to this in
> spinlock_types.h:
>
>
>    #ifdef CONFIG_DEBUG_SPINLOCK
>    # define SPIN_DEBUG_INIT(lockname)      \
>        .magic = SPINLOCK_MAGIC,        \
>        .owner_cpu = -1,            \
>        .owner = SPINLOCK_OWNER_INIT,
>    #else
>    # define SPIN_DEBUG_INIT(lockname)
>    #endif
>
>    #define __RAW_SPIN_LOCK_INITIALIZER(lockname)   \
>        {                   \
>        .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED,  \
>        SPIN_DEBUG_INIT(lockname)       \
>        SPIN_DEP_MAP_INIT(lockname) }
>
> [...]
>
>
>
> --
> John Fastabend         Intel Corporation
>


-- 
John Fastabend         Intel Corporation
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html