From: Martin Pohlack <mpohlack@amazon.com>
To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
xen-devel@lists.xenproject.org, andrew.cooper3@citrix.com,
konrad@kernel.org, mpohlack@amazon.de, ross.lagerwall@citrix.com,
sasha.levin@citrix.com, jinsong.liu@alibaba-inc.com,
Ian Campbell <ian.campbell@citrix.com>,
Ian Jackson <ian.jackson@eu.citrix.com>,
Jan Beulich <jbeulich@suse.com>, Keir Fraser <keir@xen.org>,
Tim Deegan <tim@xen.org>,
xen-devel@lists.xen.org
Subject: Re: [PATCH v3 21/23] xsplice: Add support for shadow variables
Date: Mon, 7 Mar 2016 19:52:55 +0100 [thread overview]
Message-ID: <56DDCE07.3020300@amazon.com> (raw)
In-Reply-To: <1455300361-13092-22-git-send-email-konrad.wilk@oracle.com>
On 12.02.2016 19:05, Konrad Rzeszutek Wilk wrote:
> From: Ross Lagerwall <ross.lagerwall@citrix.com>
>
> Shadow variables are a piece of infrastructure to be used by xsplice
> modules. They are used to attach a new piece of data to an existing
> structure in memory.
>
> Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
> ---
> xen/common/Makefile | 1 +
> xen/common/xsplice_shadow.c | 105 ++++++++++++++++++++++++++++++++++++++++
> xen/include/xen/xsplice_patch.h | 39 +++++++++++++++
> 3 files changed, 145 insertions(+)
> create mode 100644 xen/common/xsplice_shadow.c
> create mode 100644 xen/include/xen/xsplice_patch.h
>
> diff --git a/xen/common/Makefile b/xen/common/Makefile
> index a8ceaff..f4d54ad 100644
> --- a/xen/common/Makefile
> +++ b/xen/common/Makefile
> @@ -75,3 +75,4 @@ subdir-$(CONFIG_HAS_DEVICE_TREE) += libfdt
>
> obj-$(CONFIG_XSPLICE) += xsplice.o
> obj-$(CONFIG_XSPLICE) += xsplice_elf.o
> +obj-$(CONFIG_XSPLICE) += xsplice_shadow.o
> diff --git a/xen/common/xsplice_shadow.c b/xen/common/xsplice_shadow.c
> new file mode 100644
> index 0000000..619cdee
> --- /dev/null
> +++ b/xen/common/xsplice_shadow.c
> @@ -0,0 +1,105 @@
> +#include <xen/init.h>
> +#include <xen/kernel.h>
> +#include <xen/lib.h>
> +#include <xen/list.h>
> +#include <xen/spinlock.h>
> +#include <xen/xsplice_patch.h>
> +
> +#define SHADOW_SLOTS 256
> +struct hlist_head shadow_tbl[SHADOW_SLOTS];
Thinking about this more, how would a module using this global hash ever
be unloadable again without leaking memory?
For unloading you would need some iterator that walks all the
dynamically created shadow elements and frees them. The simplest
approach would be if each hotpatch would bring its own instance of the
hash table (if it needs it). That would allow it to fully walk and
release the hash content on its unload path.
Martin
Amazon Development Center Germany GmbH
Berlin - Dresden - Aachen
main office: Krausenstr. 38, 10117 Berlin
Geschaeftsfuehrer: Dr. Ralf Herbrich, Christian Schlaeger
Ust-ID: DE289237879
Eingetragen am Amtsgericht Charlottenburg HRB 149173 B
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
next prev parent reply other threads:[~2016-03-07 18:53 UTC|newest]
Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-12 18:05 [PATCH v3] xSplice v1 implementation and design Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 01/23] xen/xsplice: Hypervisor implementation of XEN_XSPLICE_op (v10) Konrad Rzeszutek Wilk
2016-02-12 20:11 ` Andrew Cooper
2016-02-12 20:40 ` Konrad Rzeszutek Wilk
2016-02-12 20:53 ` Andrew Cooper
2016-02-15 8:16 ` Jan Beulich
2016-02-19 19:36 ` Konrad Rzeszutek Wilk
2016-02-19 19:43 ` Andrew Cooper
2016-02-12 18:05 ` [PATCH v3 02/23] libxc: Implementation of XEN_XSPLICE_op in libxc (v5) Konrad Rzeszutek Wilk
2016-02-15 12:35 ` Wei Liu
2016-02-19 20:04 ` Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 03/23] xen-xsplice: Tool to manipulate xsplice payloads (v4) Konrad Rzeszutek Wilk
2016-02-15 12:59 ` Wei Liu
2016-02-19 20:46 ` Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 04/23] elf: Add relocation types to elfstructs.h Konrad Rzeszutek Wilk
2016-02-12 20:13 ` Andrew Cooper
2016-02-15 8:34 ` Jan Beulich
2016-02-19 21:05 ` Konrad Rzeszutek Wilk
2016-02-22 10:17 ` Jan Beulich
2016-02-22 15:19 ` Ross Lagerwall
2016-02-12 18:05 ` [PATCH v3 05/23] xsplice: Add helper elf routines (v4) Konrad Rzeszutek Wilk
2016-02-12 20:24 ` Andrew Cooper
2016-02-12 20:47 ` Konrad Rzeszutek Wilk
2016-02-12 20:52 ` Andrew Cooper
2016-02-12 18:05 ` [PATCH v3 06/23] xsplice: Implement payload loading (v4) Konrad Rzeszutek Wilk
2016-02-12 20:48 ` Andrew Cooper
2016-02-19 22:03 ` Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 07/23] xsplice: Implement support for applying/reverting/replacing patches. (v5) Konrad Rzeszutek Wilk
2016-02-16 19:11 ` Andrew Cooper
2016-02-17 8:58 ` Ross Lagerwall
2016-02-17 10:50 ` Jan Beulich
2016-02-19 9:30 ` Ross Lagerwall
2016-02-23 20:41 ` Konrad Rzeszutek Wilk
2016-02-23 20:53 ` Konrad Rzeszutek Wilk
2016-02-23 20:57 ` Konrad Rzeszutek Wilk
2016-02-23 21:10 ` Andrew Cooper
2016-02-24 9:31 ` Jan Beulich
2016-02-22 15:00 ` Ross Lagerwall
2016-02-22 17:06 ` Ross Lagerwall
2016-02-23 20:47 ` Konrad Rzeszutek Wilk
2016-02-23 20:43 ` Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 08/23] x86/xen_hello_world.xsplice: Test payload for patching 'xen_extra_version'. (v2) Konrad Rzeszutek Wilk
2016-02-16 11:31 ` Ross Lagerwall
2016-02-12 18:05 ` [PATCH v3 09/23] xsplice: Add support for bug frames. (v4) Konrad Rzeszutek Wilk
2016-02-16 19:35 ` Andrew Cooper
2016-02-24 16:22 ` Konrad Rzeszutek Wilk
2016-02-24 16:30 ` Andrew Cooper
2016-02-24 16:26 ` Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 10/23] xsplice: Add support for exception tables. (v2) Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 11/23] xsplice: Add support for alternatives Konrad Rzeszutek Wilk
2016-02-16 19:41 ` Andrew Cooper
2016-02-12 18:05 ` [PATCH v3 12/23] xsm/xen_version: Add XSM for the xen_version hypercall (v8) Konrad Rzeszutek Wilk
2016-02-12 21:52 ` Daniel De Graaf
2016-02-12 18:05 ` [PATCH v3 13/23] XENVER_build_id: Provide ld-embedded build-ids (v10) Konrad Rzeszutek Wilk
2016-02-12 21:52 ` Daniel De Graaf
2016-02-16 20:09 ` Andrew Cooper
2016-02-16 20:22 ` Konrad Rzeszutek Wilk
2016-02-16 20:26 ` Andrew Cooper
2016-02-16 20:40 ` Konrad Rzeszutek Wilk
2016-02-24 18:52 ` Konrad Rzeszutek Wilk
2016-02-24 19:13 ` Andrew Cooper
2016-02-24 20:54 ` Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 14/23] libxl: info: Display build_id of the hypervisor Konrad Rzeszutek Wilk
2016-02-15 12:45 ` Wei Liu
2016-02-12 18:05 ` [PATCH v3 15/23] xsplice: Print build_id in keyhandler Konrad Rzeszutek Wilk
2016-02-16 20:13 ` Andrew Cooper
2016-02-12 18:05 ` [PATCH v3 16/23] xsplice: basic build-id dependency checking Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 17/23] xsplice: Print dependency and payloads build_id in the keyhandler Konrad Rzeszutek Wilk
2016-02-16 20:20 ` Andrew Cooper
2016-02-17 11:10 ` Jan Beulich
2016-02-24 21:54 ` Konrad Rzeszutek Wilk
2016-02-25 8:47 ` Jan Beulich
2016-02-12 18:05 ` [PATCH v3 18/23] xsplice: Prevent duplicate payloads to be loaded Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 19/23] xsplice, symbols: Implement symbol name resolution on address. (v2) Konrad Rzeszutek Wilk
2016-02-22 14:57 ` Ross Lagerwall
2016-02-12 18:05 ` [PATCH v3 20/23] x86, xsplice: Print payload's symbol name and module in backtraces Konrad Rzeszutek Wilk
2016-02-12 18:05 ` [PATCH v3 21/23] xsplice: Add support for shadow variables Konrad Rzeszutek Wilk
2016-03-07 7:40 ` Martin Pohlack
2016-03-15 18:02 ` Konrad Rzeszutek Wilk
2016-03-07 18:52 ` Martin Pohlack [this message]
2016-02-12 18:06 ` [PATCH v3 22/23] xsplice: Add hooks functions and other macros Konrad Rzeszutek Wilk
2016-02-12 18:06 ` [PATCH v3 23/23] xsplice, hello_world: Use the XSPLICE_[UN|]LOAD_HOOK hooks for two functions Konrad Rzeszutek Wilk
2016-02-12 21:57 ` [PATCH v3] xSplice v1 implementation and design Konrad Rzeszutek Wilk
2016-02-12 21:57 ` [PATCH v3 MISSING/23] xsplice: Design document (v7) Konrad Rzeszutek Wilk
2016-02-18 16:20 ` Jan Beulich
2016-02-19 18:36 ` 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=56DDCE07.3020300@amazon.com \
--to=mpohlack@amazon.com \
--cc=andrew.cooper3@citrix.com \
--cc=ian.campbell@citrix.com \
--cc=ian.jackson@eu.citrix.com \
--cc=jbeulich@suse.com \
--cc=jinsong.liu@alibaba-inc.com \
--cc=keir@xen.org \
--cc=konrad.wilk@oracle.com \
--cc=konrad@kernel.org \
--cc=mpohlack@amazon.de \
--cc=ross.lagerwall@citrix.com \
--cc=sasha.levin@citrix.com \
--cc=tim@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 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).