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
| ||
|
Date: Thu, 21 Mar 2019 11:39:47 -0700 From: Andy Lutomirski <luto@...nel.org> To: Peter Zijlstra <peterz@...radead.org> Cc: Linus Torvalds <torvalds@...ux-foundation.org>, Andy Lutomirski <luto@...nel.org>, Andrew Cooper <andrew.cooper3@...rix.com>, Jan Beulich <jbeulich@...e.com>, Boris Ostrovsky <boris.ostrovsky@...cle.com>, Juergen Gross <jgross@...e.com>, Stefano Stabellini <sstabellini@...nel.org>, Steven Rostedt <rostedt@...dmis.org>, LKML <linux-kernel@...r.kernel.org>, "H. Peter Anvin" <hpa@...or.com>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...nel.org>, Borislav Petkov <bp@...en8.de>, Joel Fernandes <joel@...lfernandes.org>, He Zhe <zhe.he@...driver.com> Subject: Re: [RFC][PATCH] tracing/x86: Save CR2 before tracing irqsoff on error_entry On Thu, Mar 21, 2019 at 11:37 AM Peter Zijlstra <peterz@...radead.org> wrote: > > On Thu, Mar 21, 2019 at 11:25:44AM -0700, Linus Torvalds wrote: > > On Thu, Mar 21, 2019 at 11:21 AM Andy Lutomirski <luto@...nel.org> wrote: > > > > > > I dunno. Lots of people at least use to have serious commercial interest in it. > > > > Yes, it used to be a big deal. But full virtualization has gotten a > > lot more common and better. > > > > > Hey Xen folks, how close are we to being able to say "if you want to > > > run a new kernel, you need to switch to PVH or similar"? > > > > I'd also like to know if we could perhaps at least limit PV to just > > the thing that people care most deeply about. > > > > For example, maybe people notice that they really deeply care about > > the PV spinlocks because they help a lot for some loads, but don't > > care so much about the low-level CPU PV stuff any more because modern > > CPUs do _those_ things so well these days. > > > > So it might not be an all-or-nothing thing, but a gradual "let's stop > > supporting xyz under PV, because it causes pain and isn't worth it". > > So Juergen recently introduced PARAVIRT_XXL, which are exactly those > bits of PV we can get rid of. > > This paravirt-me-harder config does indeed include the CR2 bits. > > I recently talked to Andrew Cooper about this, and he said Xen Dom0 > still needs all this :/ There were patches from last year to fix that: https://lwn.net/Articles/753982/ I have no clue what the status is.
Powered by blists - more mailing lists