linux-kernel - Re: [PATCH 01/10] workqueue: add wq_numa_tbl_len and wq_numa_possible

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: <CACvQF52uoi0eX0x0mjHn0+q38nQbeMmh+NBamxpF3edGkK9zAQ@mail.gmail.com>
Date:	Thu, 21 Mar 2013 00:43:08 +0800
From:	Lai Jiangshan <eag0628@...il.com>
To:	Tejun Heo <tj@...nel.org>
Cc:	laijs@...fujitsu.com, axboe@...nel.dk, jack@...e.cz,
	fengguang.wu@...el.com, jmoyer@...hat.com, zab@...hat.com,
	linux-kernel@...r.kernel.org, herbert@...dor.apana.org.au,
	davem@...emloft.net, linux-crypto@...r.kernel.org
Subject: Re: [PATCH 01/10] workqueue: add wq_numa_tbl_len and wq_numa_possible_cpumask[]

On Wed, Mar 20, 2013 at 11:48 PM, Tejun Heo <tj@...nel.org> wrote:
> On Wed, Mar 20, 2013 at 11:43:30PM +0800, Lai Jiangshan wrote:
>> > +       for_each_node(node)
>> > +               BUG_ON(!alloc_cpumask_var_node(&wq_numa_possible_cpumask[node],
>> > +                                              GFP_KERNEL, node));
>> > +       for_each_possible_cpu(cpu) {
>> > +               node = cpu_to_node(cpu);
>> > +               if (WARN_ON(node == NUMA_NO_NODE)) {
>> > +                       pr_err("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
>>
>> since you used WARN_ON(), not BUG_ON(), I think you need to free
>> allocated memory here.
>
> I don't know.  Is it necessary?  It shouldn't happen sans bugs in arch
> code and we're vomiting warning message with full stack trace.  The
> system will function but something is seriously screwed.  I don't
> think it matters whether we free the puny number of bytes there or
> not and I don't wanna nest deeper there. :P


I agree with you, but many people use semantic analysis tools to do
hunting in the kernel. they may interrupt you again.

>
> --
> tejun
--
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/