linux-kernel - Re: [PATCH] kprobes,x86: disable irq durinr optimized callback

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: <20110510104019.GF2400@elte.hu>
Date:	Tue, 10 May 2011 12:40:19 +0200
From:	Ingo Molnar <mingo@...e.hu>
To:	Jiri Olsa <jolsa@...hat.com>
Cc:	masami.hiramatsu.pt@...achi.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] kprobes,x86: disable irq durinr optimized callback


* Jiri Olsa <jolsa@...hat.com> wrote:

> +	local_irq_save(flags);
>  	preempt_disable();
>  	if (kprobe_running()) {
>  		kprobes_inc_nmissed_count(&op->kp);
> @@ -1208,6 +1210,7 @@ static void __kprobes optimized_callback(struct optimized_kprobe *op,
>  		__this_cpu_write(current_kprobe, NULL);
>  	}
>  	preempt_enable_no_resched();
> +	local_irq_restore(flags);

irq-disable is synonymous to preempt disable so the preempt_disable()/enable() 
pair looks like superfluous overhead.

Thanks,

	Ingo
--
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/