linux-kernel - Re: [RFC/PATCH] i386: handle all exceptions with interrupts off initially

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: <20080910070014.GB31059@elte.hu>
Date:	Wed, 10 Sep 2008 09:00:14 +0200
From:	Ingo Molnar <mingo@...e.hu>
To:	"H. Peter Anvin" <hpa@...or.com>
Cc:	heukelum@...tmail.fm, linux-kernel@...r.kernel.org
Subject: Re: [RFC/PATCH] i386: handle all exceptions with interrupts off
	initially


* H. Peter Anvin <hpa@...or.com> wrote:

> Ingo Molnar wrote:
>>
>> the entry paths here are really short (we enable irqs almost 
>> immediately) so it's a non-issue in terms of worst-case latencies.
>>
>>> In other words, it's not something we want to do "just because", but 
>>> to the extent that it provides real benefit, it makes sense.
>>
>> this is historically pretty fragile code so bringing the 32-bit and 
>> 64-bit variants more in line sounds like a good reason to me. For 
>> example we had various long-living irq state annotation bugs (the 
>> combination of kprobes and lockdep, etc.) that remained unfixed 
>> partly due to this assymetry.
>
> Agreed completely.  I certainly didn't mean to come across sounding 
> negative.

great - i'll check which topic this fits in best. I suspect it will get 
its own topic - but there could be interactions as traps*.c is a central 
(and hence popular) file - here are the currently pending changes in 
-tip:

db4b0f1: kmemcheck: implement REP MOVS/STOS emulation
48e2bd5: x86: coding style fixes to arch/x86/kernel/traps_64.c
c9c3ddd: x86_64: remove empty lines from stack traces/oopses
4df9e51: x86: coding style fixes to arch/x86/kernel/traps_64.c
b359e8a: x86, xsave: context switch support using xsave/xrstor
dc1e35c: x86, xsave: enable xsave/xrstor on cpus with xsave support
862849a: x86: add hooks for kmemcheck on x86_64
787ecfa: x86: add hooks for kmemcheck
afdb702: x86: __show_registers() and __show_regs() API unification
0d84b78: x86 NMI-safe INT3 and Page Fault

we'll see.

	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/