Correct linear/virtual address terminology

As XTF uses a flat segmentation model, virtual address == linear address.
However, the terminology should be kept correct.

As a rule of thumb, a C pointer is a virtual address, while `unsigned long va`
is actually a linear address.  All pagetables are indexed in terms of linear
addresses, including the (misnamed) update_va_mapping() hypercall.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/arch/x86/include/arch/mm.h b/arch/x86/include/arch/mm.h
index e4b520c83b6da7e992bff3d7d14800c4468b56c2..f554643083f0374e74ad4dd73e92d90e9223bdb2 100644 (file)
--- a/arch/x86/include/arch/mm.h
+++ b/arch/x86/include/arch/mm.h
@@ -22,7 +22,8 @@
  *
  * XTF memory layout.
  *
- * Wherever possible, identity layout for simplicity.
+ * Wherever possible, identity layout for simplicity.  Flat segments are also
+ * used, so virtual address == linear address.
  *
  * PV guests: VIRT_OFFSET is 0 which causes all linked virtual addresses to be
  * contiguous in the pagetables created by the domain builder.  Therefore,

diff --git a/arch/x86/include/arch/page-pae.h b/arch/x86/include/arch/page-pae.h
index 7e229ea0ad228bdbfce4af460c98572c04320df9..4d87baeebd2704ae9925e36ab62dfb58da379cb8 100644 (file)
--- a/arch/x86/include/arch/page-pae.h
+++ b/arch/x86/include/arch/page-pae.h
@@ -36,22 +36,22 @@
 typedef uint64_t pae_intpte_t;
 #define PAE_PRIpte "016"PRIx64
 
-static inline unsigned int pae_l1_table_offset(unsigned long va)
+static inline unsigned int pae_l1_table_offset(unsigned long linear)
 {
-    return (va >> PAE_L1_PT_SHIFT) & (PAE_L1_PT_ENTRIES - 1);
+    return (linear >> PAE_L1_PT_SHIFT) & (PAE_L1_PT_ENTRIES - 1);
 }
-static inline unsigned int pae_l2_table_offset(unsigned long va)
+static inline unsigned int pae_l2_table_offset(unsigned long linear)
 {
-    return (va >> PAE_L2_PT_SHIFT) & (PAE_L2_PT_ENTRIES - 1);
+    return (linear >> PAE_L2_PT_SHIFT) & (PAE_L2_PT_ENTRIES - 1);
 }
-static inline unsigned int pae_l3_table_offset(unsigned long va)
+static inline unsigned int pae_l3_table_offset(unsigned long linear)
 {
-    return (va >> PAE_L3_PT_SHIFT) & (PAE_L3_PT_ENTRIES - 1);
+    return (linear >> PAE_L3_PT_SHIFT) & (PAE_L3_PT_ENTRIES - 1);
 }
 #ifdef __x86_64__
-static inline unsigned int pae_l4_table_offset(unsigned long va)
+static inline unsigned int pae_l4_table_offset(unsigned long linear)
 {
-    return (va >> PAE_L4_PT_SHIFT) & (PAE_L4_PT_ENTRIES - 1);
+    return (linear >> PAE_L4_PT_SHIFT) & (PAE_L4_PT_ENTRIES - 1);
 }
 #endif /* __x86_64__ */
 

diff --git a/arch/x86/include/arch/page-pse.h b/arch/x86/include/arch/page-pse.h
index a17f71fa1014440c2c7098c4f16b48dabbe3ae6b..fdf678a4d8645dc7ebd2b919cf62a93217412059 100644 (file)
--- a/arch/x86/include/arch/page-pse.h
+++ b/arch/x86/include/arch/page-pse.h
@@ -29,13 +29,13 @@
 typedef uint32_t pse_intpte_t;
 #define PSE_PRIpte "08"PRIx32
 
-static inline unsigned int pse_l1_table_offset(unsigned long va)
+static inline unsigned int pse_l1_table_offset(unsigned long linear)
 {
-    return (va >> PSE_L1_PT_SHIFT) & (PSE_L1_PT_ENTRIES - 1);
+    return (linear >> PSE_L1_PT_SHIFT) & (PSE_L1_PT_ENTRIES - 1);
 }
-static inline unsigned int pse_l2_table_offset(unsigned long va)
+static inline unsigned int pse_l2_table_offset(unsigned long linear)
 {
-    return (va >> PSE_L2_PT_SHIFT) & (PSE_L2_PT_ENTRIES - 1);
+    return (linear >> PSE_L2_PT_SHIFT) & (PSE_L2_PT_ENTRIES - 1);
 }
 
 static inline uint32_t fold_pse36(uint64_t val)

diff --git a/arch/x86/include/arch/page.h b/arch/x86/include/arch/page.h
index fea642616747364a181cb0815c98bc25195b375d..135cf60b6e58fae6abe9cb39e9e375a3276b87c7 100644 (file)
--- a/arch/x86/include/arch/page.h
+++ b/arch/x86/include/arch/page.h
@@ -103,13 +103,13 @@ typedef uint64_t paddr_t;
 typedef pse_intpte_t intpte_t;
 #define PRIpte PSE_PRIpte
 
-static inline unsigned int l1_table_offset(unsigned long va)
+static inline unsigned int l1_table_offset(unsigned long linear)
 {
-    return pse_l1_table_offset(va);
+    return pse_l1_table_offset(linear);
 }
-static inline unsigned int l2_table_offset(unsigned long va)
+static inline unsigned int l2_table_offset(unsigned long linear)
 {
-    return pse_l2_table_offset(va);
+    return pse_l2_table_offset(linear);
 }
 
 #else /* CONFIG_PAGING_LEVELS == 2 */ /* PAE Paging */
@@ -117,31 +117,31 @@ static inline unsigned int l2_table_offset(unsigned long va)
 typedef pae_intpte_t intpte_t;
 #define PRIpte PAE_PRIpte
 
-static inline unsigned int l1_table_offset(unsigned long va)
+static inline unsigned int l1_table_offset(unsigned long linear)
 {
-    return pae_l1_table_offset(va);
+    return pae_l1_table_offset(linear);
 }
-static inline unsigned int l2_table_offset(unsigned long va)
+static inline unsigned int l2_table_offset(unsigned long linear)
 {
-    return pae_l2_table_offset(va);
+    return pae_l2_table_offset(linear);
 }
 
 #endif /* !CONFIG_PAGING_LEVELS == 2 */
 
 #if CONFIG_PAGING_LEVELS >= 3 /* PAE Paging */
 
-static inline unsigned int l3_table_offset(unsigned long va)
+static inline unsigned int l3_table_offset(unsigned long linear)
 {
-    return pae_l3_table_offset(va);
+    return pae_l3_table_offset(linear);
 }
 
 #endif /* CONFIG_PAGING_LEVELS >= 3 */
 
 #if CONFIG_PAGING_LEVELS >= 4 /* PAE Paging */
 
-static inline unsigned int l4_table_offset(unsigned long va)
+static inline unsigned int l4_table_offset(unsigned long linear)
 {
-    return pae_l4_table_offset(va);
+    return pae_l4_table_offset(linear);
 }
 
 #endif /* CONFIG_PAGING_LEVELS >= 4 */

diff --git a/arch/x86/pv/traps.c b/arch/x86/pv/traps.c
index 0d358385dd812d56230bff9cd0affdf0cb378f56..71c8409f60f39decbbec7e027485d5feb41dcc5f 100644 (file)
--- a/arch/x86/pv/traps.c
+++ b/arch/x86/pv/traps.c
@@ -142,7 +142,7 @@ void arch_init_traps(void)
         bool leaked = false;
 
         /* Remap the page at 0 with _PAGE_USER. */
-        rc = hypercall_update_va_mapping(NULL, nl1e, UVMF_INVLPG);
+        rc = hypercall_update_va_mapping(0, nl1e, UVMF_INVLPG);
         if ( rc )
             panic("Failed to remap page at NULL with _PAGE_USER: %d\n", rc);
 
@@ -170,46 +170,46 @@ void arch_init_traps(void)
          * context.  Proceed with remapping all mappings as _PAGE_USER.
          */
         uint64_t *l3 = _p(start_info->pt_base);
-        unsigned long va = 0;
+        unsigned long linear = 0;
 
-        while ( va < __HYPERVISOR_VIRT_START_PAE )
+        while ( linear < __HYPERVISOR_VIRT_START_PAE )
         {
-            unsigned int i3 = l3_table_offset(va);
+            unsigned int i3 = l3_table_offset(linear);
 
             if ( !(l3[i3] & _PAGE_PRESENT) )
             {
-                va += 1UL << L3_PT_SHIFT;
+                linear += 1UL << L3_PT_SHIFT;
                 continue;
             }
 
             uint64_t *l2 = maddr_to_virt(pte_to_paddr(l3[i3]));
-            unsigned int i2 = l2_table_offset(va);
+            unsigned int i2 = l2_table_offset(linear);
 
             if ( !(l2[i2] & _PAGE_PRESENT) )
             {
-                va += 1UL << L2_PT_SHIFT;
+                linear += 1UL << L2_PT_SHIFT;
                 continue;
             }
 
             uint64_t *l1 = maddr_to_virt(pte_to_paddr(l2[i2]));
-            unsigned int i1 = l1_table_offset(va);
+            unsigned int i1 = l1_table_offset(linear);
 
             if ( !(l1[i1] & _PAGE_PRESENT) )
             {
-                va += 1UL << L1_PT_SHIFT;
+                linear += 1UL << L1_PT_SHIFT;
                 continue;
             }
 
             if ( !(l1[i1] & _PAGE_USER) )
             {
-                rc = hypercall_update_va_mapping(_p(va), l1[i1] | _PAGE_USER,
-                                                 UVMF_INVLPG);
+                rc = hypercall_update_va_mapping(
+                    linear, l1[i1] | _PAGE_USER, UVMF_INVLPG);
                 if ( rc )
                     panic("update_va_mapping(%p, 0x%016"PRIx64") failed: %d\n",
-                          _p(va), l1[i1] | _PAGE_USER, rc);
+                          _p(linear), l1[i1] | _PAGE_USER, rc);
             }
 
-            va += 1UL << L1_PT_SHIFT;
+            linear += 1UL << L1_PT_SHIFT;
         }
     }
     else
@@ -220,26 +220,26 @@ void arch_init_traps(void)
          */
         intpte_t nl1e = pte_from_virt(user_stack, PF_SYM(AD, U, RW, P));
 
-        if ( hypercall_update_va_mapping(user_stack, nl1e, UVMF_INVLPG) )
+        if ( hypercall_update_va_mapping(_u(user_stack), nl1e, UVMF_INVLPG) )
             panic("Unable to remap user_stack with _PAGE_USER\n");
 
         extern const char __start_user_text[], __end_user_text[];
-        unsigned long va = _u(__start_user_text);
+        unsigned long linear = _u(__start_user_text);
 
-        while ( va < _u(__end_user_text) )
+        while ( linear < _u(__end_user_text) )
         {
-            nl1e = pte_from_virt(_p(va), PF_SYM(AD, U, RW, P));
+            nl1e = pte_from_virt(_p(linear), PF_SYM(AD, U, RW, P));
 
-            if ( hypercall_update_va_mapping(_p(va), nl1e, UVMF_INVLPG) )
+            if ( hypercall_update_va_mapping(linear, nl1e, UVMF_INVLPG) )
                 panic("Unable to remap user_text with _PAGE_USER\n");
 
-            va += PAGE_SIZE;
+            linear += PAGE_SIZE;
         }
     }
 #endif
 
     /* Unmap page at 0 to catch errors with NULL pointers. */
-    rc = hypercall_update_va_mapping(NULL, 0, UVMF_INVLPG);
+    rc = hypercall_update_va_mapping(0, 0, UVMF_INVLPG);
     if ( rc )
         panic("Failed to unmap page at NULL: %d\n", rc);
 }

diff --git a/arch/x86/setup.c b/arch/x86/setup.c
index 657b5a1bfd621dcd3778c7d806feff2175faabc8..be8e5c31a40a8d651b896aedb7601c8417e8efc8 100644 (file)
--- a/arch/x86/setup.c
+++ b/arch/x86/setup.c
@@ -189,7 +189,7 @@ static void map_shared_info(void)
     }
     else /* PV */
         rc = hypercall_update_va_mapping(
-            &shared_info, start_info->shared_info | PF_SYM(RW, P),
+            _u(&shared_info), start_info->shared_info | PF_SYM(RW, P),
             UVMF_INVLPG);
 
     if ( rc )

diff --git a/include/xtf/hypercall.h b/include/xtf/hypercall.h
index aec5a12f30bece3c6c028d6cc90f6f304548cd1d..5db8b95a21c5084c7980229f23153c79cf763dc8 100644 (file)
--- a/include/xtf/hypercall.h
+++ b/include/xtf/hypercall.h
@@ -71,14 +71,18 @@ static inline long hypercall_xen_version(unsigned cmd, void *arg)
     return HYPERCALL2(long, __HYPERVISOR_xen_version, cmd, arg);
 }
 
-static inline long hypercall_update_va_mapping(void *va, uint64_t npte,
-                                               enum XEN_UVMF flags)
+/*
+ * This hypercall is misnamed in the Xen ABI, and actually operates on a
+ * linear address, not a virtual address.
+ */
+static inline long hypercall_update_va_mapping(
+    unsigned long linear, uint64_t npte, enum XEN_UVMF flags)
 {
 #ifdef __x86_64__
-    return HYPERCALL3(long, __HYPERVISOR_update_va_mapping, va, npte, flags);
+    return HYPERCALL3(long, __HYPERVISOR_update_va_mapping, linear, npte, flags);
 #else
     return HYPERCALL4(long, __HYPERVISOR_update_va_mapping,
-                      va, npte, npte >> 32, flags);
+                      linear, npte, npte >> 32, flags);
 #endif
 }
 

diff --git a/tests/xsa-182/main.c b/tests/xsa-182/main.c
index 9164978bc9602b2923841d19c3a19dff1e304e53..2c750e1fe0f6976e5990639a9d9da9342c462f4d 100644 (file)
--- a/tests/xsa-182/main.c
+++ b/tests/xsa-182/main.c
@@ -38,7 +38,7 @@ void test_main(void)
     intpte_t *l4 = _p(KB(4));
 
     /* Map the L4 at 4K virtual. */
-    if ( hypercall_update_va_mapping(l4, nl1e, UVMF_INVLPG) )
+    if ( hypercall_update_va_mapping(_u(l4), nl1e, UVMF_INVLPG) )
         return xtf_error("Error: Update va failed\n");
 
     unsigned long map_slot = 0, test_slot = 0;

diff --git a/tests/xsa-195/main.c b/tests/xsa-195/main.c
index 945b50b1df5709314b2196b531ab150d870d0f8e..cbf89d4df4fa9a14a4d1225a19087a301fc610e8 100644 (file)
--- a/tests/xsa-195/main.c
+++ b/tests/xsa-195/main.c
@@ -43,11 +43,11 @@ void test_main(void)
     unsigned long mem_adjust = (8 + ((-idx - 1) >> 3)) & ~7;
 
     /*
-     * va is the memory target which the `bt` instruction will actually hit.
+     * linear is the memory target which the `bt` instruction will actually hit.
      * A vulnerable Xen mis-calculates the memory adjustment, meaning that it
      * will attempt to read from some other address.
      */
-    unsigned long va = _u(mem) - mem_adjust;
+    unsigned long linear = _u(mem) - mem_adjust;
 
     /*
      * Make all of the virtual address space readable, so Xen's data fetch
@@ -61,11 +61,11 @@ void test_main(void)
     for ( i = 1; i < L4_PT_ENTRIES; ++i )
         pae_l4_identmap[i] = pae_l4_identmap[0] & ~PF_SYM(RW);
 
-    /* Map va to pointing specifically to gfn 0. */
-    nl1t[l1_table_offset(va)] = pte_from_gfn(0, PF_SYM(U, P));
-    nl2t[l2_table_offset(va)] = pte_from_virt(nl1t, PF_SYM(U, P));
-    nl3t[l3_table_offset(va)] = pte_from_virt(nl2t, PF_SYM(U, P));
-    pae_l4_identmap[l4_table_offset(va)] = pte_from_virt(nl3t, PF_SYM(U, P));
+    /* Map linear to pointing specifically to gfn 0. */
+    nl1t[l1_table_offset(linear)] = pte_from_gfn(0, PF_SYM(U, P));
+    nl2t[l2_table_offset(linear)] = pte_from_virt(nl1t, PF_SYM(U, P));
+    nl3t[l3_table_offset(linear)] = pte_from_virt(nl2t, PF_SYM(U, P));
+    pae_l4_identmap[l4_table_offset(linear)] = pte_from_virt(nl3t, PF_SYM(U, P));
 
     /* Remove gfn 0 from the p2m, to cause `bt` to trap for emulation. */
     static unsigned long extent = 0;