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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 23 Jul 2014 17:23:11 +0200 From: Borislav Petkov <bp@...en8.de> To: Andy Lutomirski <luto@...capital.net> Cc: "H. Peter Anvin" <hpa@...ux.intel.com>, Linus Torvalds <torvalds@...ux-foundation.org>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, X86 ML <x86@...nel.org> Subject: Re: STI architectural question (and lretq -- I'm not even kidding) On Wed, Jul 23, 2014 at 08:12:32AM -0700, Andy Lutomirski wrote: > How are we supposed to survive two machine checks in rapid succession? > The second will fire as soon as the first one is acked, I imagine. > Unless we switch stacks before acking the MCE, the return address of > the first one will be lost. Oh, that might not fly but in that case the box probably deserves to die anyway. I was adressing what you said earlier: "But here's the problem: what happens if an NMI or MCE happens between the sti and the lretq? I think an MCE just might be okay -- it's not really recoverable anyway." An MC Exception can be recoverable and we can recover. The fact that we raise an exception doesn't always mean we die. -- 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/
Powered by blists - more mailing lists