linux-kernel - Re: [RFC][PATCH 2/6] x86, nmi: create new NMI handler routines

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: <1314022580.24275.33.camel@twins>
Date:	Mon, 22 Aug 2011 16:16:20 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Don Zickus <dzickus@...hat.com>
Cc:	x86@...nel.org, Andi Kleen <andi@...stfloor.org>,
	Robert Richter <robert.richter@....com>, ying.huang@...el.com,
	LKML <linux-kernel@...r.kernel.org>, jason.wessel@...driver.com
Subject: Re: [RFC][PATCH 2/6] x86, nmi: create new NMI handler routines

On Fri, 2011-08-19 at 16:37 -0400, Don Zickus wrote:
> +static struct nmiaction *__free_nmi(unsigned int type, const char *name)
> +{
> +       struct nmi_desc *desc = nmi_to_desc(type);
> +       struct nmiaction *n, **np = &(desc->head);
> +       unsigned long flags;
> +
> +       spin_lock_irqsave(&desc->lock, flags);
> +
...
> +
> +       spin_unlock_irqrestore(&desc->lock, flags);
> +       synchronize_rcu();
> +       return *np;
> +}

> +void unregister_nmi_handler(unsigned int type, const char *name)
> +{
> +       kfree(__free_nmi(type, name));
> +}

This code is weird.. why not have the kfree() in __free_nmi(), also why
use sync_rcu() and not use kfree_rcu()?

> +EXPORT_SYMBOL_GPL(unregister_nmi_handler); 

*g*, so binary modules can register an NMI handler, but can't unregister
it..?
--
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/