| Message ID | 20240227112528.4540-6-roger.pau@citrix.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | xen/livepatch: fixes for the pre-apply / post-revert hooks | expand |
On Tue, Feb 27, 2024 at 11:25 AM Roger Pau Monne <roger.pau@citrix.com> wrote: > > Group the payload hooks between the pre/post handlers, and the apply/revert > replacements. Also attempt to comment the context in which the hooks are > executed. > > No functional change. > > Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> > --- > Changes since v1: > - New in this version. > --- > xen/include/xen/livepatch_payload.h | 37 ++++++++++++++++++++++------- > 1 file changed, 29 insertions(+), 8 deletions(-) > > diff --git a/xen/include/xen/livepatch_payload.h b/xen/include/xen/livepatch_payload.h > index b9cd4f209670..472d6a4a63c1 100644 > --- a/xen/include/xen/livepatch_payload.h > +++ b/xen/include/xen/livepatch_payload.h > @@ -82,6 +82,8 @@ struct payload { > * collision. Since multiple hooks can be registered, the > * .livepatch.hook.load section is a table of functions that will be > * executed in series by the livepatch infrastructure at patch load time. > + * > + * Note the load hook is executed in quiesced context. > */ > #define LIVEPATCH_LOAD_HOOK(_fn) \ > livepatch_loadcall_t *__weak \ > @@ -96,14 +98,20 @@ struct payload { > livepatch_unloadcall_t *__weak \ > const livepatch_unload_data_##_fn __section(".livepatch.hooks.unload") = _fn; > > +/* > + * Pre/Post action hooks. > + * > + * This hooks are executed before or after the livepatch application. Pre hooks > + * can veto the application/revert of the livepatch. They are not executed in > + * quiesced context. All of pre and post hooks are considered vetoing, and > + * hence filling any of those will block the usage of the REPLACE action. > + * > + * Each of the hooks below can only be set once per livepatch payload. > + */ > #define LIVEPATCH_PREAPPLY_HOOK(_fn) \ > livepatch_precall_t *__attribute__((weak, used)) \ > const livepatch_preapply_data_##_fn __section(".livepatch.hooks.preapply") = _fn; > > -#define LIVEPATCH_APPLY_HOOK(_fn) \ > - livepatch_actioncall_t *__attribute__((weak, used)) \ > - const livepatch_apply_data_##_fn __section(".livepatch.hooks.apply") = _fn; > - > #define LIVEPATCH_POSTAPPLY_HOOK(_fn) \ > livepatch_postcall_t *__attribute__((weak, used)) \ > const livepatch_postapply_data_##_fn __section(".livepatch.hooks.postapply") = _fn; > @@ -112,14 +120,27 @@ struct payload { > livepatch_precall_t *__attribute__((weak, used)) \ > const livepatch_prerevert_data_##_fn __section(".livepatch.hooks.prerevert") = _fn; > > -#define LIVEPATCH_REVERT_HOOK(_fn) \ > - livepatch_actioncall_t *__attribute__((weak, used)) \ > - const livepatch_revert_data_##_fn __section(".livepatch.hooks.revert") = _fn; > - > #define LIVEPATCH_POSTREVERT_HOOK(_fn) \ > livepatch_postcall_t *__attribute__((weak, used)) \ > const livepatch_postrevert_data_##_fn __section(".livepatch.hooks.postrevert") = _fn; > > +/* > + * Action replacement hooks. > + * > + * The following hooks replace the hypervisor implementation for the livepatch > + * application and revert routines. When filling the hooks below the native > + * apply and revert routines will not be executed, so the provided hooks need > + * to make sure the state of the payload after apply or revert is as expected > + * by the livepatch logic. > + */ > +#define LIVEPATCH_APPLY_HOOK(_fn) \ > + livepatch_actioncall_t *__attribute__((weak, used)) \ > + const livepatch_apply_data_##_fn __section(".livepatch.hooks.apply") = _fn; > + > +#define LIVEPATCH_REVERT_HOOK(_fn) \ > + livepatch_actioncall_t *__attribute__((weak, used)) \ > + const livepatch_revert_data_##_fn __section(".livepatch.hooks.revert") = _fn; > + > #endif /* __XEN_LIVEPATCH_PAYLOAD_H__ */ > LGTM, thanks. Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
diff --git a/xen/include/xen/livepatch_payload.h b/xen/include/xen/livepatch_payload.h index b9cd4f209670..472d6a4a63c1 100644 --- a/xen/include/xen/livepatch_payload.h +++ b/xen/include/xen/livepatch_payload.h @@ -82,6 +82,8 @@ struct payload { * collision. Since multiple hooks can be registered, the * .livepatch.hook.load section is a table of functions that will be * executed in series by the livepatch infrastructure at patch load time. + * + * Note the load hook is executed in quiesced context. */ #define LIVEPATCH_LOAD_HOOK(_fn) \ livepatch_loadcall_t *__weak \ @@ -96,14 +98,20 @@ struct payload { livepatch_unloadcall_t *__weak \ const livepatch_unload_data_##_fn __section(".livepatch.hooks.unload") = _fn; +/* + * Pre/Post action hooks. + * + * This hooks are executed before or after the livepatch application. Pre hooks + * can veto the application/revert of the livepatch. They are not executed in + * quiesced context. All of pre and post hooks are considered vetoing, and + * hence filling any of those will block the usage of the REPLACE action. + * + * Each of the hooks below can only be set once per livepatch payload. + */ #define LIVEPATCH_PREAPPLY_HOOK(_fn) \ livepatch_precall_t *__attribute__((weak, used)) \ const livepatch_preapply_data_##_fn __section(".livepatch.hooks.preapply") = _fn; -#define LIVEPATCH_APPLY_HOOK(_fn) \ - livepatch_actioncall_t *__attribute__((weak, used)) \ - const livepatch_apply_data_##_fn __section(".livepatch.hooks.apply") = _fn; - #define LIVEPATCH_POSTAPPLY_HOOK(_fn) \ livepatch_postcall_t *__attribute__((weak, used)) \ const livepatch_postapply_data_##_fn __section(".livepatch.hooks.postapply") = _fn; @@ -112,14 +120,27 @@ struct payload { livepatch_precall_t *__attribute__((weak, used)) \ const livepatch_prerevert_data_##_fn __section(".livepatch.hooks.prerevert") = _fn; -#define LIVEPATCH_REVERT_HOOK(_fn) \ - livepatch_actioncall_t *__attribute__((weak, used)) \ - const livepatch_revert_data_##_fn __section(".livepatch.hooks.revert") = _fn; - #define LIVEPATCH_POSTREVERT_HOOK(_fn) \ livepatch_postcall_t *__attribute__((weak, used)) \ const livepatch_postrevert_data_##_fn __section(".livepatch.hooks.postrevert") = _fn; +/* + * Action replacement hooks. + * + * The following hooks replace the hypervisor implementation for the livepatch + * application and revert routines. When filling the hooks below the native + * apply and revert routines will not be executed, so the provided hooks need + * to make sure the state of the payload after apply or revert is as expected + * by the livepatch logic. + */ +#define LIVEPATCH_APPLY_HOOK(_fn) \ + livepatch_actioncall_t *__attribute__((weak, used)) \ + const livepatch_apply_data_##_fn __section(".livepatch.hooks.apply") = _fn; + +#define LIVEPATCH_REVERT_HOOK(_fn) \ + livepatch_actioncall_t *__attribute__((weak, used)) \ + const livepatch_revert_data_##_fn __section(".livepatch.hooks.revert") = _fn; + #endif /* __XEN_LIVEPATCH_PAYLOAD_H__ */ /*
Group the payload hooks between the pre/post handlers, and the apply/revert replacements. Also attempt to comment the context in which the hooks are executed. No functional change. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> --- Changes since v1: - New in this version. --- xen/include/xen/livepatch_payload.h | 37 ++++++++++++++++++++++------- 1 file changed, 29 insertions(+), 8 deletions(-)