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-rw-r--r--main/xen/xsa344-2.patch210
1 files changed, 0 insertions, 210 deletions
diff --git a/main/xen/xsa344-2.patch b/main/xen/xsa344-2.patch
deleted file mode 100644
index c03344bdd39..00000000000
--- a/main/xen/xsa344-2.patch
+++ /dev/null
@@ -1,210 +0,0 @@
-From: Jan Beulich <jbeulich@suse.com>
-Subject: evtchn: arrange for preemption in evtchn_reset()
-
-Like for evtchn_destroy() looping over all possible event channels to
-close them can take a significant amount of time. Unlike done there, we
-can't alter domain properties (i.e. d->valid_evtchns) here. Borrow, in a
-lightweight form, the paging domctl continuation concept, redirecting
-the continuations to different sub-ops. Just like there this is to be
-able to allow for predictable overall results of the involved sub-ops:
-Racing requests should either complete or be refused.
-
-Note that a domain can't interfere with an already started (by a remote
-domain) reset, due to being paused. It can prevent a remote reset from
-happening by leaving a reset unfinished, but that's only going to affect
-itself.
-
-This is part of XSA-344.
-
-Signed-off-by: Jan Beulich <jbeulich@suse.com>
-Acked-by: Julien Grall <jgrall@amazon.com>
-Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
----
-v9: Undo v7 changes.
-v7: Move extension of loop condition in evtchn_reset() here, to match
- the earlier patch'es change to evtchn_destroy().
-v6: Also protect the last write of d->next_evtchn. Re-base over changes
- to earlier patches.
-v4: New.
-
---- a/xen/common/domain.c
-+++ b/xen/common/domain.c
-@@ -1145,7 +1145,7 @@ void domain_unpause_except_self(struct d
- domain_unpause(d);
- }
-
--int domain_soft_reset(struct domain *d)
-+int domain_soft_reset(struct domain *d, bool resuming)
- {
- struct vcpu *v;
- int rc;
-@@ -1159,7 +1159,7 @@ int domain_soft_reset(struct domain *d)
- }
- spin_unlock(&d->shutdown_lock);
-
-- rc = evtchn_reset(d);
-+ rc = evtchn_reset(d, resuming);
- if ( rc )
- return rc;
-
---- a/xen/common/domctl.c
-+++ b/xen/common/domctl.c
-@@ -477,12 +477,22 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xe
- }
-
- case XEN_DOMCTL_soft_reset:
-+ case XEN_DOMCTL_soft_reset_cont:
- if ( d == current->domain ) /* no domain_pause() */
- {
- ret = -EINVAL;
- break;
- }
-- ret = domain_soft_reset(d);
-+ ret = domain_soft_reset(d, op->cmd == XEN_DOMCTL_soft_reset_cont);
-+ if ( ret == -ERESTART )
-+ {
-+ op->cmd = XEN_DOMCTL_soft_reset_cont;
-+ if ( !__copy_field_to_guest(u_domctl, op, cmd) )
-+ ret = hypercall_create_continuation(__HYPERVISOR_domctl,
-+ "h", u_domctl);
-+ else
-+ ret = -EFAULT;
-+ }
- break;
-
- case XEN_DOMCTL_destroydomain:
---- a/xen/common/event_channel.c
-+++ b/xen/common/event_channel.c
-@@ -1057,7 +1057,7 @@ int evtchn_unmask(unsigned int port)
- return 0;
- }
-
--int evtchn_reset(struct domain *d)
-+int evtchn_reset(struct domain *d, bool resuming)
- {
- unsigned int i;
- int rc = 0;
-@@ -1065,11 +1065,40 @@ int evtchn_reset(struct domain *d)
- if ( d != current->domain && !d->controller_pause_count )
- return -EINVAL;
-
-- for ( i = 0; port_is_valid(d, i); i++ )
-+ spin_lock(&d->event_lock);
-+
-+ /*
-+ * If we are resuming, then start where we stopped. Otherwise, check
-+ * that a reset operation is not already in progress, and if none is,
-+ * record that this is now the case.
-+ */
-+ i = resuming ? d->next_evtchn : !d->next_evtchn;
-+ if ( i > d->next_evtchn )
-+ d->next_evtchn = i;
-+
-+ spin_unlock(&d->event_lock);
-+
-+ if ( !i )
-+ return -EBUSY;
-+
-+ for ( ; port_is_valid(d, i); i++ )
-+ {
- evtchn_close(d, i, 1);
-
-+ /* NB: Choice of frequency is arbitrary. */
-+ if ( !(i & 0x3f) && hypercall_preempt_check() )
-+ {
-+ spin_lock(&d->event_lock);
-+ d->next_evtchn = i;
-+ spin_unlock(&d->event_lock);
-+ return -ERESTART;
-+ }
-+ }
-+
- spin_lock(&d->event_lock);
-
-+ d->next_evtchn = 0;
-+
- if ( d->active_evtchns > d->xen_evtchns )
- rc = -EAGAIN;
- else if ( d->evtchn_fifo )
-@@ -1204,7 +1233,8 @@ long do_event_channel_op(int cmd, XEN_GU
- break;
- }
-
-- case EVTCHNOP_reset: {
-+ case EVTCHNOP_reset:
-+ case EVTCHNOP_reset_cont: {
- struct evtchn_reset reset;
- struct domain *d;
-
-@@ -1217,9 +1247,13 @@ long do_event_channel_op(int cmd, XEN_GU
-
- rc = xsm_evtchn_reset(XSM_TARGET, current->domain, d);
- if ( !rc )
-- rc = evtchn_reset(d);
-+ rc = evtchn_reset(d, cmd == EVTCHNOP_reset_cont);
-
- rcu_unlock_domain(d);
-+
-+ if ( rc == -ERESTART )
-+ rc = hypercall_create_continuation(__HYPERVISOR_event_channel_op,
-+ "ih", EVTCHNOP_reset_cont, arg);
- break;
- }
-
---- a/xen/include/public/domctl.h
-+++ b/xen/include/public/domctl.h
-@@ -1159,7 +1159,10 @@ struct xen_domctl {
- #define XEN_DOMCTL_iomem_permission 20
- #define XEN_DOMCTL_ioport_permission 21
- #define XEN_DOMCTL_hypercall_init 22
--#define XEN_DOMCTL_arch_setup 23 /* Obsolete IA64 only */
-+#ifdef __XEN__
-+/* #define XEN_DOMCTL_arch_setup 23 Obsolete IA64 only */
-+#define XEN_DOMCTL_soft_reset_cont 23
-+#endif
- #define XEN_DOMCTL_settimeoffset 24
- #define XEN_DOMCTL_getvcpuaffinity 25
- #define XEN_DOMCTL_real_mode_area 26 /* Obsolete PPC only */
---- a/xen/include/public/event_channel.h
-+++ b/xen/include/public/event_channel.h
-@@ -74,6 +74,9 @@
- #define EVTCHNOP_init_control 11
- #define EVTCHNOP_expand_array 12
- #define EVTCHNOP_set_priority 13
-+#ifdef __XEN__
-+#define EVTCHNOP_reset_cont 14
-+#endif
- /* ` } */
-
- typedef uint32_t evtchn_port_t;
---- a/xen/include/xen/event.h
-+++ b/xen/include/xen/event.h
-@@ -171,7 +171,7 @@ void evtchn_check_pollers(struct domain
- void evtchn_2l_init(struct domain *d);
-
- /* Close all event channels and reset to 2-level ABI. */
--int evtchn_reset(struct domain *d);
-+int evtchn_reset(struct domain *d, bool resuming);
-
- /*
- * Low-level event channel port ops.
---- a/xen/include/xen/sched.h
-+++ b/xen/include/xen/sched.h
-@@ -371,6 +371,8 @@ struct domain
- * EVTCHNOP_reset). Read/write access like for active_evtchns.
- */
- unsigned int xen_evtchns;
-+ /* Port to resume from in evtchn_reset(), when in a continuation. */
-+ unsigned int next_evtchn;
- spinlock_t event_lock;
- const struct evtchn_port_ops *evtchn_port_ops;
- struct evtchn_fifo_domain *evtchn_fifo;
-@@ -663,7 +665,7 @@ int domain_kill(struct domain *d);
- int domain_shutdown(struct domain *d, u8 reason);
- void domain_resume(struct domain *d);
-
--int domain_soft_reset(struct domain *d);
-+int domain_soft_reset(struct domain *d, bool resuming);
-
- int vcpu_start_shutdown_deferral(struct vcpu *v);
- void vcpu_end_shutdown_deferral(struct vcpu *v);
generated by cgit v1.2.3 (git 2.41.0) at 2024-04-19 23:37:07 +0000