xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Julien Grall <julien.grall@arm.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: xen-devel@lists.xenproject.org, ross.lagerwall@citrix.com,
	sstabellini@kernel.org
Subject: Re: [PATCH v2] Livepatch for ARM 64 and 32.
Date: Wed, 31 Aug 2016 16:24:29 +0100	[thread overview]
Message-ID: <25ec381c-3ca5-c06c-d95f-bdbbd24917cb@citrix.com> (raw)
In-Reply-To: <1ea514e1-1bf7-6029-311d-c7798af8e424@arm.com>

On 31/08/16 16:09, Julien Grall wrote:
>
>
> On 31/08/16 16:06, Konrad Rzeszutek Wilk wrote:
>> On Wed, Aug 31, 2016 at 03:49:55PM +0100, Julien Grall wrote:
>>> On 25/08/16 14:37, Konrad Rzeszutek Wilk wrote:
>>>> Hey!
>>>
>>> Hi Konrad,
>>>
>>>> Since v1 (and RFC):
>>>> [https://lists.xen.org/archives/html/xen-devel/2016-08/msg01835.html]
>>>>  - Acted on most all comments.
>>>>  - Added ARM32 support.
>>>>
>>>> The patches are based on: [PATCH v4] Livepatch fixes and features
>>>> for v4.8.
>>>> (https://lists.xen.org/archives/html/xen-devel/2016-08/msg02705.html)
>>>>
>>>> And the git tree is:
>>>>  git://xenbits.xen.org/people/konradwilk/xen.git livepatch.v4.8.v4
>>>>
>>>> There are two outstanding questions that should be addressed at
>>>> some point:
>>>>  -  #16 "livepatch: tests: Make them compile under ARM64"
>>>>     We chatted about adding a specific CPU bit (LIVEPATCH) so that
>>>> alternative
>>>>     code always gets exercised. This being for both x86 and ARM.
>>>> But this has
>>>>     a side effect that it gets exposed to the toolstack and can
>>>> also be
>>>>     exposed to the guests. I think it is better if we do not do that
>>>>     so left it to be enabled based on the most common errata (or
>>>> feature
>>>>     on x86).
>>>
>>> There is no common errata on ARM. I spoke with Andrew which
>>> mentioned that
>>> on x86 they have architectural xen feature bits which are not
>>> exposed to the
>>> toolstack/guest.
>>>
>>> Furthermore, I think it would be unwise to let the toolstack aware
>>> of some
>>> errata and possibly setting/clearing them. So adding a specific
>>> feature bit
>>> is fine by me.
>>
>> So you are thinking of exposing this 'xen feature bits' that Andrew
>> mention
>> to be on ARM as well.
>
> I only chat with Andrew about it and I have not looked at the code, so
> I can't tell how it is on x86. I was just thinking to add LIVEPATCH
> bit in cpufeature.h for now and be worry later when cpufeature will be
> exposed to the toolstack for ARM.

Sorry - I have forgotten what exactly the purpose of this bit needs to
be, and therefore which bit of x86 I point you at.

~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel

  reply	other threads:[~2016-08-31 15:24 UTC|newest]

Thread overview: 72+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-25 13:37 [PATCH v2] Livepatch for ARM 64 and 32 Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 01/20] livepatch: Bubble up sanity checks on Elf relocs Konrad Rzeszutek Wilk
2016-08-25 14:48   ` Jan Beulich
2016-09-06 17:13   ` Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 02/20] x86/arm: Make 'make debug' work properly Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 03/20] x86/arm64: Expose the ALT_[ORIG|REPL]_PTR macros to header files Konrad Rzeszutek Wilk
2016-08-31 15:43   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 04/20] alternatives: x86 rename and change parameters on ARM Konrad Rzeszutek Wilk
2016-08-25 13:55   ` Andrew Cooper
2016-08-31 15:44   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 05/20] arm64/alternatives: Make it possible to patch outside of hypervisor Konrad Rzeszutek Wilk
2016-08-31 15:54   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 06/20] arm/alternative: Use _start instead of _stext Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 07/20] arm/x86: Add ALTERNATIVE and HAS_EX_TABLE Konrad Rzeszutek Wilk
2016-08-25 13:58   ` Andrew Cooper
2016-08-25 14:02     ` Julien Grall
2016-08-25 14:09       ` Andrew Cooper
2016-08-25 14:56     ` Jan Beulich
2016-09-06 20:36       ` Konrad Rzeszutek Wilk
2016-09-06 20:40         ` Konrad Rzeszutek Wilk
2016-08-25 14:54   ` Jan Beulich
2016-09-06 20:16     ` Konrad Rzeszutek Wilk
2016-09-07  8:17       ` Jan Beulich
2016-08-25 13:37 ` [PATCH v2 08/20] x86: change modify_xen_mappings to return error Konrad Rzeszutek Wilk
2016-08-25 13:53   ` Andrew Cooper
2016-08-25 13:37 ` [PATCH v2 09/20] arm/mm: Introduce modify_xen_mappings Konrad Rzeszutek Wilk
2016-09-01 13:04   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 10/20] arm64/insn: introduce aarch64_insn_gen_{nop|branch_imm}() helper functions Konrad Rzeszutek Wilk
2016-09-01 13:10   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 11/20] arm/arm64: Update comment about VA layout Konrad Rzeszutek Wilk
2016-09-01 13:11   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 12/20] x86, arm: Change arch_livepatch_quiesce() decleration Konrad Rzeszutek Wilk
2016-08-25 13:59   ` Andrew Cooper
2016-09-01 13:13   ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 13/20] livepatch: Initial ARM64 support Konrad Rzeszutek Wilk
2016-08-25 15:02   ` Jan Beulich
2016-09-07  2:58     ` Konrad Rzeszutek Wilk
2016-09-01 14:16   ` Julien Grall
2016-09-07  0:31     ` Konrad Rzeszutek Wilk
2016-09-07  3:33       ` Konrad Rzeszutek Wilk
2016-09-07 10:43         ` Julien Grall
2016-09-07 15:20           ` Konrad Rzeszutek Wilk
2016-09-07 10:41       ` Julien Grall
2016-08-25 13:37 ` [PATCH v2 14/20] livepatch: ARM 32|64: Ignore mapping symbols: $[d, a, x, t] Konrad Rzeszutek Wilk
2016-08-25 14:03   ` Andrew Cooper
2016-09-01 14:48   ` Julien Grall
2016-09-06 18:57     ` Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 15/20] livepatch: Move test-cases to common Konrad Rzeszutek Wilk
2016-08-25 15:05   ` Jan Beulich
2016-09-06 17:16     ` Konrad Rzeszutek Wilk
2016-09-07  8:28       ` Jan Beulich
2016-09-06 17:17   ` Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 16/20] livepatch: tests: Make them compile under ARM64 Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 17/20] xen/arm32: Add an helper to invalidate all instruction caches Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 18/20] xen/arm32/livepatch: Add BPICALLIS to " Konrad Rzeszutek Wilk
2016-09-01 15:13   ` Julien Grall
2016-09-01 20:23     ` Konrad Rzeszutek Wilk
2016-09-06 19:39     ` Konrad Rzeszutek Wilk
2016-08-25 13:37 ` [PATCH v2 19/20] livepatch/elf: Adjust section aligment to word Konrad Rzeszutek Wilk
2016-08-25 15:11   ` Jan Beulich
2016-09-01 15:27     ` Julien Grall
2016-09-06 21:18     ` Konrad Rzeszutek Wilk
2016-09-07  8:24       ` Jan Beulich
2016-08-25 13:37 ` [PATCH v2 20/20] livepatch: ARM32 support Konrad Rzeszutek Wilk
2016-09-08 10:34   ` Konrad Rzeszutek Wilk
2016-08-31 14:49 ` [PATCH v2] Livepatch for ARM 64 and 32 Julien Grall
2016-08-31 15:06   ` Konrad Rzeszutek Wilk
2016-08-31 15:09     ` Julien Grall
2016-08-31 15:24       ` Andrew Cooper [this message]
2016-08-31 15:40         ` Julien Grall
2016-08-31 15:54         ` Jan Beulich
2016-09-07  4:05           ` Konrad Rzeszutek Wilk

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=25ec381c-3ca5-c06c-d95f-bdbbd24917cb@citrix.com \
    --to=andrew.cooper3@citrix.com \
    --cc=julien.grall@arm.com \
    --cc=konrad.wilk@oracle.com \
    --cc=ross.lagerwall@citrix.com \
    --cc=sstabellini@kernel.org \
    --cc=xen-devel@lists.xenproject.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).