linux-kernel - Re: 2.6.23 regression: accessing invalid mmap'ed memory from gdb causes unkillable spinning

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] [day] [month] [year] [list]

Date:	Fri, 2 Nov 2007 16:36:43 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Nick Piggin <npiggin@...e.de>
Cc:	David Miller <davem@...emloft.net>, duaneg@...da.com,
	linux-kernel@...r.kernel.org
Subject: Re: 2.6.23 regression: accessing invalid mmap'ed memory from gdb
	causes unkillable spinning


* Nick Piggin <npiggin@...e.de> wrote:

> > This means that even if some cpu is stuck in a spinlock loop with 
> > interrupts disabled, you'd see it with this thing.  The way it works 
> > is that cross cpu vectored interrupts are disabled independently of 
> > the processor interrupt level on sparc64.
> 
> That's really sweet. I'd better put my code where my mouth is as 
> well... this patch seems to be about the best we can do as a generic 
> fallback without getting a dedicated vector (which has to be done in 
> arch code anyway).

btw., in -rt we had something like this implemented as an NMI mechanism 
(for x86) - that way it's guaranteed that we get some output even from 
locked up CPUs.

	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/