Re: [Qemu-devel] Regression: Xen guest with 5G of RAM on 32bit fail to boot

[Paolo Bonzini <pbonzini@redhat.com>]

On 01/12/2015 18:53, Anthony PERARD wrote:
> The problem is in qemu_ram_alloc_internal() where 'size' and 'maxsize' are
> now been truncate to 32bit, due to 'qemu_host_page_size' been an uintptr_t
> in the HOST_PAGE_ALIGN macro.

Isn't it qemu_host_page_mask that causes the problem?

This should also work, as it causes qemu_host_page_mask to sign-extend:

diff --git a/include/exec/cpu-all.h b/include/exec/cpu-all.h
index f9998b9..87a4145 100644
--- a/include/exec/cpu-all.h
+++ b/include/exec/cpu-all.h
@@ -174,11 +174,10 @@ extern unsigned long reserved_va;
 #define TARGET_PAGE_MASK ~(TARGET_PAGE_SIZE - 1)
 #define TARGET_PAGE_ALIGN(addr) (((addr) + TARGET_PAGE_SIZE - 1) & TARGET_PAGE_MASK)
 
-/* ??? These should be the larger of uintptr_t and target_ulong.  */
 extern uintptr_t qemu_real_host_page_size;
-extern uintptr_t qemu_real_host_page_mask;
+extern intptr_t qemu_real_host_page_mask;
 extern uintptr_t qemu_host_page_size;
-extern uintptr_t qemu_host_page_mask;
+extern intptr_t qemu_host_page_mask;
 
 #define HOST_PAGE_ALIGN(addr) (((addr) + qemu_host_page_size - 1) & qemu_host_page_mask)
 #define REAL_HOST_PAGE_ALIGN(addr) (((addr) + qemu_real_host_page_size - 1) & \
diff --git a/translate-all.c b/translate-all.c
index a940bd2..7a15109 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -118,7 +118,7 @@ typedef struct PageDesc {
 #define V_L1_SHIFT (L1_MAP_ADDR_SPACE_BITS - TARGET_PAGE_BITS - V_L1_BITS)
 
 uintptr_t qemu_host_page_size;
-uintptr_t qemu_host_page_mask;
+intptr_t qemu_host_page_mask;
 
 /* The bottom level has pointers to PageDesc */
 static void *l1_map[V_L1_SIZE];
@@ -326,14 +326,14 @@ void page_size_init(void)
     /* NOTE: we can always suppose that qemu_host_page_size >=
        TARGET_PAGE_SIZE */
     qemu_real_host_page_size = getpagesize();
-    qemu_real_host_page_mask = ~(qemu_real_host_page_size - 1);
+    qemu_real_host_page_mask = -(intptr_t)qemu_real_host_page_size;
     if (qemu_host_page_size == 0) {
         qemu_host_page_size = qemu_real_host_page_size;
     }
     if (qemu_host_page_size < TARGET_PAGE_SIZE) {
         qemu_host_page_size = TARGET_PAGE_SIZE;
     }
-    qemu_host_page_mask = ~(qemu_host_page_size - 1);
+    qemu_host_page_mask = -(intptr_t)qemu_host_page_size;
 }
 
 static void page_init(void)
diff --git a/translate-common.c b/translate-common.c
index 619feb4..171222d 100644
--- a/translate-common.c
+++ b/translate-common.c
@@ -21,7 +21,7 @@
 #include "qom/cpu.h"
 
 uintptr_t qemu_real_host_page_size;
-uintptr_t qemu_real_host_page_mask;
+intptr_t qemu_real_host_page_mask;
 
 #ifndef CONFIG_USER_ONLY
 /* mask must never be zero, except for A20 change call */