linux-kernel - Re: [PATCH] x86, amd, mce: Prevent potential cpu-online oops

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, 4 Apr 2013 18:13:40 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Daniel J Blueman <daniel@...ascale-asia.com>
Cc:	Tony Luck <tony.luck@...el.com>, Borislav Petkov <bp@...en8.de>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>, x86@...nel.org,
	linux-edac@...r.kernel.org, linux-kernel@...r.kernel.org,
	Steffen Persvold <sp@...ascale.com>
Subject: Re: [PATCH] x86, amd, mce: Prevent potential cpu-online oops

On Thu, Apr 04, 2013 at 11:52:00PM +0800, Daniel J Blueman wrote:
> On platforms where all Northbridges may not be visible (due to routing, eg on
> NumaConnect systems), prevent oopsing due to stale pointer access when
> offlining cores.
> 
> Signed-off-by: Steffen Persvold <sp@...ascale.com>
> Signed-off-by: Daniel J Blueman <daniel@...ascale-asia.com>

Huh, what's up?

This one is almost reverting 21c5e50e15b1a which you wrote in the first
place. What's happening? What stale pointer access, where? We have the
if (nb ..) guards there.

This commit message needs a *lot* more explanation about what's going
on and why we're reverting 21c5e50e15b1a. And why the special handling
for shared banks? I presume you offline some of the cores and there's a
dangling pointer but again, there are the nb validity guards...

/me is genuinely confused.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
--
--
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/