[Qemu-devel] [PATCH 02/24] Fix cpu_physical_memory_rw when operating on IO blocks.

[Tristan Gingold]

In some cases, addr was destroyed and the next access was wrong.  This
occured while making 64bits IO accesses.

Signed-off-by: Tristan Gingold <address@hidden>
---
 exec.c |   26 +++++++++++++++-----------
 1 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/exec.c b/exec.c
index fd3e441..76a89ca 100644
--- a/exec.c
+++ b/exec.c
@@ -357,16 +357,16 @@ static PhysPageDesc 
*phys_page_find_alloc(target_phys_addr_t index, int alloc)
 
     /* Level 2..n-1 */
     for (i = (L1_SHIFT / L2_BITS) - 1; i > 0; i--) {
-       p = *lp;
-       if (!p) {
-           /* allocate if not found */
-           if (!alloc)
-               return NULL;
-           p = qemu_vmalloc(sizeof(void *) * L2_SIZE);
-           memset(p, 0, sizeof(void *) * L2_SIZE);
-           *lp = p;
-       }
-       lp = p + ((index >> (i * L2_BITS)) & (L2_SIZE - 1));
+        p = *lp;
+        if (!p) {
+            /* allocate if not found */
+            if (!alloc)
+                return NULL;
+            p = qemu_vmalloc(sizeof(void *) * L2_SIZE);
+            memset(p, 0, sizeof(void *) * L2_SIZE);
+            *lp = p;
+        }
+        lp = p + ((index >> (i * L2_BITS)) & (L2_SIZE - 1));
     }
 #else
     p = (void **)l1_phys_map;
@@ -2987,6 +2987,7 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, 
uint8_t *buf,
     target_phys_addr_t page;
     unsigned long pd;
     PhysPageDesc *p;
+    unsigned long addr1;
 
     while (len > 0) {
         page = addr & TARGET_PAGE_MASK;
@@ -3006,6 +3007,8 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, 
uint8_t *buf,
                 io_index = (pd >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1);
                 if (p)
                     addr1 = (addr & ~TARGET_PAGE_MASK) + p->region_offset;
+                else
+                    addr1 = addr;
                 /* XXX: could force cpu_single_env to NULL to avoid
                    potential bugs */
                 if (l >= 4 && ((addr1 & 3) == 0)) {
@@ -3025,7 +3028,6 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, 
uint8_t *buf,
                     l = 1;
                 }
             } else {
-                unsigned long addr1;
                 addr1 = (pd & TARGET_PAGE_MASK) + (addr & ~TARGET_PAGE_MASK);
                 /* RAM case */
                 ptr = phys_ram_base + addr1;
@@ -3046,6 +3048,8 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, 
uint8_t *buf,
                 io_index = (pd >> IO_MEM_SHIFT) & (IO_MEM_NB_ENTRIES - 1);
                 if (p)
                     addr1 = (addr & ~TARGET_PAGE_MASK) + p->region_offset;
+                else
+                    addr1 = addr;
                 if (l >= 4 && ((addr1 & 3) == 0)) {
                     /* 32 bit read access */
                     val = io_mem_read[io_index][2](io_mem_opaque[io_index], 
addr1);
-- 
1.6.2