x86/mm: partially revert 21093:4a3e131f7498

p2m internals should always gate on whether HAP is enabled for the
domain, not whether a HAP paging mode is currently advertised.
This lets us revert the change to hap_enable() that advertises the
new mode before it's safe to use it.

Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>

diff --git a/xen/arch/x86/mm/hap/hap.c b/xen/arch/x86/mm/hap/hap.c
index 8d1bc70efabaadf469b74ea535cc8d4c411f2c2e..2a4d09662f1ce5d0c6fa0323dc78d5ef8dcceeac 100644 (file)
--- a/xen/arch/x86/mm/hap/hap.c
+++ b/xen/arch/x86/mm/hap/hap.c
@@ -583,13 +583,9 @@ int hap_enable(struct domain *d, u32 mode)
 {
     unsigned int old_pages;
     int rv = 0;
-    uint32_t oldmode;
 
     domain_pause(d);
 
-    oldmode = d->arch.paging.mode;
-    d->arch.paging.mode = mode | PG_HAP_enable;
-
     /* error check */
     if ( (d == current->domain) )
     {
@@ -624,9 +620,10 @@ int hap_enable(struct domain *d, u32 mode)
             goto out;
     }
 
+    /* Now let other users see the new mode */
+    d->arch.paging.mode = mode | PG_HAP_enable;
+
  out:
-    if (rv)
-        d->arch.paging.mode = oldmode;
     domain_unpause(d);
     return rv;
 }

diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index 6d9e8ac52aadef53751a3a099b093898f7fd3f31..ed16b1551fd61a7b2901652ce35536df34794123 100644 (file)
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -1387,7 +1387,7 @@ p2m_set_entry(struct p2m_domain *p2m, unsigned long gfn, mfn_t mfn,
     else if ( !p2m_next_level(p2m, &table_mfn, &table, &gfn_remainder, gfn,
                               L3_PAGETABLE_SHIFT - PAGE_SHIFT,
                               ((CONFIG_PAGING_LEVELS == 3)
-                               ? (paging_mode_hap(p2m->domain) ? 4 : 8)
+                               ? (hap_enabled(p2m->domain) ? 4 : 8)
                                : L3_PAGETABLE_ENTRIES),
                               PGT_l2_page_table) )
         goto out;
@@ -1848,7 +1848,7 @@ int set_p2m_entry(struct p2m_domain *p2m, unsigned long gfn, mfn_t mfn,
 
     while ( todo )
     {
-        if ( is_hvm_domain(d) && paging_mode_hap(d) )
+        if ( hap_enabled(d) )
             order = ( (((gfn | mfn_x(mfn) | todo) & ((1ul << 18) - 1)) == 0) &&
                       hvm_hap_has_1gb(d) && opt_hap_1gb ) ? 18 :
                       ((((gfn | mfn_x(mfn) | todo) & ((1ul << 9) - 1)) == 0) &&
@@ -1909,8 +1909,7 @@ int p2m_alloc_table(struct p2m_domain *p2m)
 
     p2m->phys_table = pagetable_from_mfn(page_to_mfn(p2m_top));
 
-    if ( is_hvm_domain(d) && d->arch.hvm_domain.hap_enabled &&
-         (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) )
+    if ( hap_enabled(d) && (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) )
         iommu_set_pgd(d);
 
     P2M_PRINTK("populating p2m table\n");
@@ -2314,7 +2313,7 @@ static int gfn_check_limit(
      * hardware translation limit. This limitation is checked by comparing
      * gfn with 0xfffffUL.
      */
-    if ( !paging_mode_hap(d) || ((gfn + (1ul << order)) <= 0x100000UL) ||
+    if ( !hap_enabled(d) || ((gfn + (1ul << order)) <= 0x100000UL)
          (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) )
         return 0;