linux-kernel - Re: [PATCH] x86: fix wakeup

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: <20081117173527.GA2827@elte.hu>
Date:	Mon, 17 Nov 2008 18:35:27 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Cyrill Gorcunov <gorcunov@...il.com>
Cc:	Yinghai Lu <yinghai@...nel.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] x86: fix wakeup_cpu with numaq/es7000 v2


* Cyrill Gorcunov <gorcunov@...il.com> wrote:

> [Ingo Molnar - Mon, Nov 17, 2008 at 05:52:24PM +0100]
> | 
> | * Yinghai Lu <yinghai@...nel.org> wrote:
> | 
> | > Impact: fix wakeup path with numaq and es7000
> | 
> | applied	to tip/x86/quirks, thanks Yinghai!
> | 
> | A couple of comments:
> | 
> | > +static inline void inquire_remote_apic(int apicid)
> | > +{
> | > +	if (apic_verbosity >= APIC_DEBUG)
> | > +		__inquire_remote_apic(apicid);
> | > +}
> |
> 
> Btw, Ingo, Yinghai,
> 
> it's a bit weird but I found that we use apic_verbosity
> here to _do_ something (ie touching circuit) but on any
> other cases apic_verbosity is just a additional logging
> filter so -- what the initial apic_verbosity purpose was?
> If it's just a logging filter (to which I'm more biased)
> this case is plain wrong. But if apic_verbosity is not
> like this -- then it's fine. Since I was not initial author
> of the code -- I'm asking you :)

the reason why it's dependent on apic_verbosity is that the 
inquire_remote_apic() function is a debug function which we only call 
if we fail to start up a secondary CPU.

Perhaps renaming it to debug_print_remote_apic() would have made that 
more obvious.

	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/