From: Konrad Rzeszutek Wilk <konrad@darnok.org>
To: "Hansen, Dave" <dave.hansen@intel.com>
Cc: "Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>,
"Andi Kleen" <ak@linux.intel.com>,
"Linus Torvalds" <torvalds@linux-foundation.org>,
"David Woodhouse" <dwmw2@infradead.org>,
"Liran Alon" <liran.alon@oracle.com>,
"Laura Abbott" <labbott@redhat.com>,
"Andrew Lutomirski" <luto@kernel.org>,
"Janakarajan Natarajan" <Janakarajan.Natarajan@amd.com>,
"Borislav Petkov" <bp@suse.de>,
"Mallick, Asit K" <asit.k.mallick@intel.com>,
"Radim Krčmář" <rkrcmar@redhat.com>,
"KarimAllah Ahmed" <karahmed@amazon.de>,
"Peter Anvin" <hpa@zytor.com>,
"Nakajima, Jun" <jun.nakajima@intel.com>,
"Ingo Molnar" <mingo@redhat.com>,
"the arch/x86 maintainers" <x86@kernel.org>,
"Raj, Ashok" <ashok.raj@intel.com>,
"Van De Ven, Arjan" <arjan.van.de.ven@intel.com>,
"Tim Chen" <tim.c.chen@linux.intel.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
"Peter Zijlstra" <peterz@infradead.org>,
"Thomas Gleixner" <tglx@linutronix.de>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
"Masami Hiramatsu" <mhiramat@kernel.org>,
"Arjan van de Ven" <arjan@linux.intel.com>,
"Tom Lendacky" <thomas.lendacky@amd.com>,
"Williams, Dan J" <dan.j.williams@intel.com>,
"Joerg Roedel" <joro@8bytes.org>,
"Andrea Arcangeli" <aarcange@redhat.com>,
"KVM list" <kvm@vger.kernel.org>,
"Boris Ostrovsky" <boris.ostrovsky@oracle.com>
Subject: Re: [RFC 09/10] x86/enter: Create macros to restrict/unrestrict Indirect Branch Speculation
Date: Sat, 27 Jan 2018 08:42:43 -0500 [thread overview]
Message-ID: <20180127134239.GA25029@localhost.localdomain> (raw)
In-Reply-To: <0089A7AA75120F4087B2E7CB6BF3E53442A9AA0A@CRSMSX104.amr.corp.intel.com>
On Fri, Jan 26, 2018 at 07:11:47PM +0000, Hansen, Dave wrote:
> The need for RSB stuffing in all the various scenarios and what the heck it actually mitigates is freakishly complicated. I've tried to write it all down in one place: https://goo.gl/pXbvBE
Thank you for sharing that.
One question on the third from the top (' RSB Stuff (16) After
irq/nmi/#PF/...').
It says that :"Return from interrupt path (more than 16 deep) can empty
RSB".
Just to clarify - you mean all the returns ('ret') that are happening after
we call do_IRQ and the stack unwinds - but before we do an 'iret' correct?
I am 99% sure that is what you mean, but just confirming as one could read
this as: 'Need to do RSB after an iret' (say you are in the kernel
and then get an interrupt and iret back to kernel).
next prev parent reply other threads:[~2018-01-27 13:42 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-26 2:11 [RFC 09/10] x86/enter: Create macros to restrict/unrestrict Indirect Branch Speculation Liran Alon
2018-01-26 2:23 ` Dave Hansen
2018-01-26 9:11 ` David Woodhouse
2018-01-26 17:19 ` Linus Torvalds
2018-01-26 17:27 ` Borislav Petkov
2018-01-26 17:29 ` David Woodhouse
2018-01-26 17:31 ` David Woodhouse
2018-01-26 17:59 ` Andi Kleen
2018-01-26 18:11 ` David Woodhouse
2018-01-26 18:12 ` Arjan van de Ven
2018-01-26 18:26 ` David Woodhouse
2018-01-26 18:28 ` Van De Ven, Arjan
2018-01-26 18:43 ` David Woodhouse
2018-01-26 18:44 ` Van De Ven, Arjan
2018-01-26 18:53 ` David Woodhouse
2018-01-26 19:02 ` Konrad Rzeszutek Wilk
2018-01-26 19:11 ` Hansen, Dave
2018-01-27 13:42 ` Konrad Rzeszutek Wilk [this message]
2018-01-27 15:55 ` Dave Hansen
2018-01-26 19:11 ` David Woodhouse
2018-01-26 8:46 ` David Woodhouse
-- strict thread matches above, loose matches on Subject: below --
2018-01-26 2:50 Liran Alon
2018-01-26 2:55 ` Van De Ven, Arjan
2018-01-23 11:13 Liran Alon
2018-01-25 22:20 ` Dave Hansen
2018-01-22 22:15 Luke Kenneth Casson Leighton
2018-01-20 19:22 [RFC 00/10] Speculation Control feature support KarimAllah Ahmed
2018-01-20 19:23 ` [RFC 09/10] x86/enter: Create macros to restrict/unrestrict Indirect Branch Speculation KarimAllah Ahmed
2018-01-21 19:14 ` Andy Lutomirski
2018-01-23 16:12 ` Tom Lendacky
2018-01-23 16:20 ` Woodhouse, David
2018-01-23 22:37 ` Tom Lendacky
2018-01-23 22:49 ` Andi Kleen
2018-01-23 23:14 ` Woodhouse, David
2018-01-23 23:22 ` Andi Kleen
2018-01-24 0:47 ` Tim Chen
2018-01-24 1:00 ` Andy Lutomirski
2018-01-24 1:22 ` David Woodhouse
2018-01-24 1:59 ` Van De Ven, Arjan
2018-01-24 3:25 ` Andy Lutomirski
2018-01-21 19:34 ` Linus Torvalds
2018-01-21 20:28 ` David Woodhouse
2018-01-21 21:35 ` Linus Torvalds
2018-01-21 22:00 ` David Woodhouse
2018-01-21 22:27 ` Linus Torvalds
2018-01-22 16:27 ` David Woodhouse
2018-01-23 7:29 ` Ingo Molnar
2018-01-23 7:53 ` Ingo Molnar
2018-01-23 9:27 ` Ingo Molnar
2018-01-23 9:37 ` David Woodhouse
2018-01-23 15:01 ` Dave Hansen
2018-01-23 9:30 ` David Woodhouse
2018-01-23 10:15 ` Ingo Molnar
2018-01-23 10:27 ` David Woodhouse
2018-01-23 10:44 ` Ingo Molnar
2018-01-23 10:57 ` David Woodhouse
2018-01-23 10:23 ` Ingo Molnar
2018-01-23 10:35 ` David Woodhouse
2018-02-04 18:43 ` Thomas Gleixner
2018-02-04 20:22 ` David Woodhouse
2018-02-06 9:14 ` David Woodhouse
2018-01-25 16:19 ` Mason
2018-01-25 17:16 ` Greg Kroah-Hartman
2018-01-29 11:59 ` Mason
2018-01-24 0:05 ` Andi Kleen
2018-01-23 20:16 ` Pavel Machek
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