When enabling log dirty mode, it sets all guest's memory to readonly.

And in HAP enabled domain, it modifies all EPT entries to clear write bit
to make sure it is readonly. This will cause problem if VT-d shares page
table with EPT: the device may issue a DMA write request, then VT-d engine
tells it the target memory is readonly and result in VT-d fault.

Currnetly, there are two places will enable log dirty mode: migration and vram
tracking. Migration with device assigned is not allowed, so it is ok. For vram,
it doesn't need to set all memory to readonly. Only track the vram range is enough.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Acked-by: Tim Deegan <tim@xen.org>

diff --git a/xen/arch/x86/mm/hap/hap.c b/xen/arch/x86/mm/hap/hap.c
index d3f64bdb9764bb884d57be0560f37324ec7a1d60..5f756366aa3e9c2825133054160d78e55cc5693d 100644 (file)
--- a/xen/arch/x86/mm/hap/hap.c
+++ b/xen/arch/x86/mm/hap/hap.c
@@ -82,7 +82,7 @@ int hap_track_dirty_vram(struct domain *d,
         if ( !paging_mode_log_dirty(d) )
         {
             hap_logdirty_init(d);
-            rc = paging_log_dirty_enable(d);
+            rc = paging_log_dirty_enable(d, 0);
             if ( rc )
                 goto out;
         }
@@ -167,17 +167,25 @@ out:
 /*            HAP LOG DIRTY SUPPORT             */
 /************************************************/
 
-/* hap code to call when log_dirty is enable. return 0 if no problem found. */
-static int hap_enable_log_dirty(struct domain *d)
+/*
+ * hap code to call when log_dirty is enable. return 0 if no problem found.
+ *
+ * NB: Domain that having device assigned should not set log_global. Because
+ * there is no way to track the memory updating from device.
+ */
+static int hap_enable_log_dirty(struct domain *d, bool_t log_global)
 {
     /* turn on PG_log_dirty bit in paging mode */
     paging_lock(d);
     d->arch.paging.mode |= PG_log_dirty;
     paging_unlock(d);
 
-    /* set l1e entries of P2M table to be read-only. */
-    p2m_change_entry_type_global(d, p2m_ram_rw, p2m_ram_logdirty);
-    flush_tlb_mask(d->domain_dirty_cpumask);
+    if ( log_global )
+    {
+        /* set l1e entries of P2M table to be read-only. */
+        p2m_change_entry_type_global(d, p2m_ram_rw, p2m_ram_logdirty);
+        flush_tlb_mask(d->domain_dirty_cpumask);
+    }
     return 0;
 }
 

diff --git a/xen/arch/x86/mm/paging.c b/xen/arch/x86/mm/paging.c
index 21344e50ff4d510844fb1571f14a904d73cca6e7..ab5eacbb7b7fb3606f722a73285e0f37a1738311 100644 (file)
--- a/xen/arch/x86/mm/paging.c
+++ b/xen/arch/x86/mm/paging.c
@@ -164,7 +164,7 @@ void paging_free_log_dirty_bitmap(struct domain *d)
     paging_unlock(d);
 }
 
-int paging_log_dirty_enable(struct domain *d)
+int paging_log_dirty_enable(struct domain *d, bool_t log_global)
 {
     int ret;
 
@@ -172,7 +172,7 @@ int paging_log_dirty_enable(struct domain *d)
         return -EINVAL;
 
     domain_pause(d);
-    ret = d->arch.paging.log_dirty.enable_log_dirty(d);
+    ret = d->arch.paging.log_dirty.enable_log_dirty(d, log_global);
     domain_unpause(d);
 
     return ret;
@@ -489,7 +489,8 @@ void paging_log_dirty_range(struct domain *d,
  * These function pointers must not be followed with the log-dirty lock held.
  */
 void paging_log_dirty_init(struct domain *d,
-                           int    (*enable_log_dirty)(struct domain *d),
+                           int    (*enable_log_dirty)(struct domain *d,
+                                                      bool_t log_global),
                            int    (*disable_log_dirty)(struct domain *d),
                            void   (*clean_dirty_bitmap)(struct domain *d))
 {
@@ -590,7 +591,7 @@ int paging_domctl(struct domain *d, xen_domctl_shadow_op_t *sc,
     case XEN_DOMCTL_SHADOW_OP_ENABLE_LOGDIRTY:
         if ( hap_enabled(d) )
             hap_logdirty_init(d);
-        return paging_log_dirty_enable(d);
+        return paging_log_dirty_enable(d, 1);
 
     case XEN_DOMCTL_SHADOW_OP_OFF:
         if ( paging_mode_log_dirty(d) )

diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c
index 0bfa595298eae1d85ba8925c5e43910c2a3a68e4..11c6b6273cd595beb562eacacf1d99d216a98592 100644 (file)
--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -3418,7 +3418,7 @@ shadow_write_p2m_entry(struct vcpu *v, unsigned long gfn,
 /* Shadow specific code which is called in paging_log_dirty_enable().
  * Return 0 if no problem found.
  */
-int shadow_enable_log_dirty(struct domain *d)
+int shadow_enable_log_dirty(struct domain *d, bool_t log_global)
 {
     int ret;
 

diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h
index ea72db2c3edcac764fbdd535509464be4e8ccdc6..4ff89f01eac52a4de58c32d564290d9ad93cf255 100644 (file)
--- a/xen/include/asm-x86/domain.h
+++ b/xen/include/asm-x86/domain.h
@@ -169,7 +169,7 @@ struct log_dirty_domain {
     unsigned int   dirty_count;
 
     /* functions which are paging mode specific */
-    int            (*enable_log_dirty   )(struct domain *d);
+    int            (*enable_log_dirty   )(struct domain *d, bool_t log_global);
     int            (*disable_log_dirty  )(struct domain *d);
     void           (*clean_dirty_bitmap )(struct domain *d);
 };

diff --git a/xen/include/asm-x86/paging.h b/xen/include/asm-x86/paging.h
index cd7ee3be66b290174ff15419b86fd5e225ade6da..8dd2a61367f9dd067c22fc38f83e15c0623f7bf6 100644 (file)
--- a/xen/include/asm-x86/paging.h
+++ b/xen/include/asm-x86/paging.h
@@ -143,14 +143,15 @@ void paging_log_dirty_range(struct domain *d,
                             uint8_t *dirty_bitmap);
 
 /* enable log dirty */
-int paging_log_dirty_enable(struct domain *d);
+int paging_log_dirty_enable(struct domain *d, bool_t log_global);
 
 /* disable log dirty */
 int paging_log_dirty_disable(struct domain *d);
 
 /* log dirty initialization */
 void paging_log_dirty_init(struct domain *d,
-                           int  (*enable_log_dirty)(struct domain *d),
+                           int  (*enable_log_dirty)(struct domain *d,
+                                                    bool_t log_global),
                            int  (*disable_log_dirty)(struct domain *d),
                            void (*clean_dirty_bitmap)(struct domain *d));
 

diff --git a/xen/include/asm-x86/shadow.h b/xen/include/asm-x86/shadow.h
index 852023de79a67e10ce990b907dab9e8e8376291e..348915e669f6f74850a1c937f8305a2906cd2f9e 100644 (file)
--- a/xen/include/asm-x86/shadow.h
+++ b/xen/include/asm-x86/shadow.h
@@ -82,7 +82,7 @@ void shadow_teardown(struct domain *d);
 void shadow_final_teardown(struct domain *d);
 
 /* shadow code to call when log dirty is enabled */
-int shadow_enable_log_dirty(struct domain *d);
+int shadow_enable_log_dirty(struct domain *d, bool_t log_global);
 
 /* shadow code to call when log dirty is disabled */
 int shadow_disable_log_dirty(struct domain *d);