x86/domain: don't destroy IOREQ servers on soft reset

Performing soft reset should not opportunistically kill IOREQ servers
for device emulators that might be currently running for a domain.
Every emulator is supposed to clean up IOREQ servers for itself on exit.
This allows a toolstack to elect whether or not a particular device
model should be restarted.

The original code was introduced in 3235cbfe ("arch-specific hooks for
domain_soft_reset()") likely due to the fact 'default' IOREQ server
existed in Xen at the time and used by QEMU didn't have an API call to
destroy. Since the removal of 'default' IOREQ server from Xen this
reason has gone away.

Since commit ba7fdd64b ("xen: cleanup IOREQ server on exit") QEMU now
destroys IOREQ server for itself as every other device emulator
is supposed to do. It's now safe to remove this code from soft reset
path - existing systems with old QEMU should be able to work as
even if there are IOREQ servers left behind, a new QEMU instance will
override its ranges anyway.

Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
index 2df312332dbbc172b39c13cc350e9260c85ad536..957f05937fad4c57fd080e52f2497475b640ba03 100644 (file)
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -713,8 +713,6 @@ int arch_domain_soft_reset(struct domain *d)
     if ( !is_hvm_domain(d) )
         return -EINVAL;
 
-    hvm_domain_soft_reset(d);
-
     spin_lock(&d->event_lock);
     for ( i = 0; i < d->nr_pirqs ; i++ )
     {

diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 029eea3b859358691f358eb245b24fb394d885c2..2b8189946b249ad98850524a0c16bd934feb60a4 100644 (file)
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -5045,11 +5045,6 @@ void hvm_toggle_singlestep(struct vcpu *v)
     v->arch.hvm.single_step = !v->arch.hvm.single_step;
 }
 
-void hvm_domain_soft_reset(struct domain *d)
-{
-    hvm_destroy_all_ioreq_servers(d);
-}
-
 /*
  * Segment caches in VMCB/VMCS are inconsistent about which bits are checked,
  * important, and preserved across vmentry/exit.  Cook the values to make them

diff --git a/xen/include/asm-x86/hvm/hvm.h b/xen/include/asm-x86/hvm/hvm.h
index b327bd2524720ac9a7577e52c846057bc18f6cd8..4e72d0732e2912eafd4264fed2b45e73903476cb 100644 (file)
--- a/xen/include/asm-x86/hvm/hvm.h
+++ b/xen/include/asm-x86/hvm/hvm.h
@@ -240,7 +240,6 @@ extern const struct hvm_function_table *start_vmx(void);
 int hvm_domain_initialise(struct domain *d);
 void hvm_domain_relinquish_resources(struct domain *d);
 void hvm_domain_destroy(struct domain *d);
-void hvm_domain_soft_reset(struct domain *d);
 
 int hvm_vcpu_initialise(struct vcpu *v);
 void hvm_vcpu_destroy(struct vcpu *v);