From: Julien Grall <julien.grall@arm.com>
To: "Wieczorkiewicz, Pawel" <wipawel@amazon.de>
Cc: "Tim Deegan" <tim@xen.org>,
"Stefano Stabellini" <sstabellini@kernel.org>,
"Wei Liu" <wl@xen.org>,
"Konrad Rzeszutek Wilk" <konrad.wilk@oracle.com>,
"George Dunlap" <George.Dunlap@eu.citrix.com>,
"Andrew Cooper" <andrew.cooper3@citrix.com>,
"Ian Jackson" <ian.jackson@eu.citrix.com>,
xen-devel <xen-devel@lists.xen.org>,
"Pohlack, Martin" <mpohlack@amazon.de>,
"Ross Lagerwall" <ross.lagerwall@citrix.com>,
"Jan Beulich" <jbeulich@suse.com>,
xen-devel <xen-devel@lists.xenproject.org>,
"Roger Pau Monné" <roger.pau@citrix.com>
Subject: Re: [Xen-devel] [PATCH 09/14] livepatch: Add per-function applied/reverted state tracking marker
Date: Thu, 22 Aug 2019 16:30:40 +0100 [thread overview]
Message-ID: <9a2a6d52-f247-ff18-0cce-593162e33755@arm.com> (raw)
In-Reply-To: <DB27F58E-DA27-4A5D-BE23-4CDB5D9736A2@amazon.com>
Hi Pawel,
On 22/08/2019 12:02, Wieczorkiewicz, Pawel wrote:
>> On 22. Aug 2019, at 12:29, Julien Grall <julien.grall@arm.com
>> <mailto:julien.grall@arm.com>> wrote:
>> On 21/08/2019 09:19, Pawel Wieczorkiewicz wrote:
>> More generally, I am not very comfortable to see panic() in the middle of the
>> code. Could you explain why panic is the best solution over reverting the work?
>>
>
> Yes. Production-ready hotpatches must not contain inconsistent hooks or
> functions-to-be-applied/reverted.
> The goal here is to detect such hotpatches and fail hard immediately
> highlighting the fact that such hotpatch
> is broken.
Aside the len = 0 that you are going to fix. How would this condition happen?
Are you going to add code that will potentially trigger the panic?
>
> The inconsistent application of a hotpatch (some function applied, some reverted
> while other left behined) leaves
> the system in a very bad state. I think the best what we could do here is
> panic() to enable post-mortem analysis
> of what went wrong and avoid leaking such system into production.
Thank you for the explanation here (and on IRC). May I ask some documentation
regarding the panic in at least commit message? Ideally, this would explain why
the panic the most sensible solution.
Cheers,
--
Julien Grall
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
next prev parent reply other threads:[~2019-08-22 15:31 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-21 8:19 [Xen-devel] [PATCH 00/14] livepatch: new features and fixes Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 01/14] livepatch: Always check hypervisor build ID upon hotpatch upload Pawel Wieczorkiewicz
2019-08-21 18:16 ` Konrad Rzeszutek Wilk
2019-08-21 8:19 ` [Xen-devel] [PATCH 02/14] livepatch: Allow to override inter-modules buildid dependency Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 03/14] python: Add XC binding for Xen build ID Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 04/14] livepatch: Export payload structure via livepatch_payload.h Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 05/14] livepatch: Implement pre-|post- apply|revert hooks Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 06/14] livepatch: Add support for apply|revert action replacement hooks Pawel Wieczorkiewicz
2019-08-21 18:31 ` Konrad Rzeszutek Wilk
2019-08-21 19:06 ` Wieczorkiewicz, Pawel
2019-08-26 14:30 ` Konrad Rzeszutek Wilk
2019-08-21 8:19 ` [Xen-devel] [PATCH 07/14] livepatch: Do not enforce ELF_LIVEPATCH_FUNC section presence Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 08/14] livepatch: always print XENLOG_ERR information Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 09/14] livepatch: Add per-function applied/reverted state tracking marker Pawel Wieczorkiewicz
2019-08-21 18:28 ` Konrad Rzeszutek Wilk
2019-08-21 19:00 ` Wieczorkiewicz, Pawel
2019-08-21 21:34 ` Julien Grall
2019-08-22 7:44 ` Wieczorkiewicz, Pawel
2019-08-22 10:07 ` Julien Grall
2019-08-22 10:20 ` Wieczorkiewicz, Pawel
2019-08-22 10:43 ` Julien Grall
2019-08-22 11:15 ` Wieczorkiewicz, Pawel
2019-08-22 15:02 ` Julien Grall
2019-08-22 10:29 ` Julien Grall
2019-08-22 11:02 ` Wieczorkiewicz, Pawel
2019-08-22 15:30 ` Julien Grall [this message]
2019-08-22 15:42 ` Wieczorkiewicz, Pawel
2019-08-21 8:19 ` [Xen-devel] [PATCH 10/14] livepatch: Add support for inline asm hotpatching expectations Pawel Wieczorkiewicz
2019-08-21 18:30 ` Konrad Rzeszutek Wilk
2019-08-21 19:02 ` Wieczorkiewicz, Pawel
2019-08-22 10:31 ` Julien Grall
2019-08-22 11:03 ` Wieczorkiewicz, Pawel
2019-08-21 8:19 ` [Xen-devel] [PATCH 11/14] livepatch: Add support for modules .modinfo section metadata Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 12/14] livepatch: Handle arbitrary size names with the list operation Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 13/14] livepatch: Add metadata runtime retrieval mechanism Pawel Wieczorkiewicz
2019-08-21 8:19 ` [Xen-devel] [PATCH 14/14] livepatch: Add python bindings for livepatch operations Pawel Wieczorkiewicz
2019-08-22 21:55 ` Marek Marczykowski-Górecki
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 00/12] livepatch: new features and fixes Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 01/12] livepatch: Always check hypervisor build ID upon hotpatch upload Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 02/12] livepatch: Allow to override inter-modules buildid dependency Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 03/12] livepatch: Export payload structure via livepatch_payload.h Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 04/12] livepatch: Implement pre-|post- apply|revert hooks Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 05/12] livepatch: Add support for apply|revert action replacement hooks Pawel Wieczorkiewicz
2019-08-27 16:58 ` Konrad Rzeszutek Wilk
2019-08-28 7:37 ` Wieczorkiewicz, Pawel
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 06/12] livepatch: Do not enforce ELF_LIVEPATCH_FUNC section presence Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 07/12] livepatch: Add per-function applied/reverted state tracking marker Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 08/12] livepatch: Add support for inline asm hotpatching expectations Pawel Wieczorkiewicz
2019-08-29 14:34 ` Konrad Rzeszutek Wilk
2019-08-29 15:29 ` Wieczorkiewicz, Pawel
2019-08-29 15:58 ` Konrad Rzeszutek Wilk
2019-08-29 16:16 ` Wieczorkiewicz, Pawel
2019-08-29 17:49 ` Konrad Rzeszutek Wilk
2019-08-29 19:07 ` Wieczorkiewicz, Pawel
2019-08-29 20:48 ` Konrad Rzeszutek Wilk
2019-09-05 18:05 ` Konrad Rzeszutek Wilk
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 09/12] livepatch: Add support for modules .modinfo section metadata Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 10/12] livepatch: Handle arbitrary size names with the list operation Pawel Wieczorkiewicz
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 11/12] livepatch: Add metadata runtime retrieval mechanism Pawel Wieczorkiewicz
2019-08-29 20:48 ` Konrad Rzeszutek Wilk
2019-08-27 8:46 ` [Xen-devel] [PATCH v2 12/12] livepatch: Add python bindings for livepatch operations Pawel Wieczorkiewicz
2019-08-28 13:21 ` Marek Marczykowski-Górecki
2019-08-29 19:23 ` [Xen-devel] [PATCH v2 00/12] livepatch: new features and fixes Konrad Rzeszutek Wilk
2019-09-05 19:13 ` Konrad Rzeszutek Wilk
2019-09-06 22:52 ` Julien Grall
2019-09-06 22:42 ` Julien Grall
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=9a2a6d52-f247-ff18-0cce-593162e33755@arm.com \
--to=julien.grall@arm.com \
--cc=George.Dunlap@eu.citrix.com \
--cc=andrew.cooper3@citrix.com \
--cc=ian.jackson@eu.citrix.com \
--cc=jbeulich@suse.com \
--cc=konrad.wilk@oracle.com \
--cc=mpohlack@amazon.de \
--cc=roger.pau@citrix.com \
--cc=ross.lagerwall@citrix.com \
--cc=sstabellini@kernel.org \
--cc=tim@xen.org \
--cc=wipawel@amazon.de \
--cc=wl@xen.org \
--cc=xen-devel@lists.xen.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.