[Xen-devel] [PATCH] Fix >4G i386 PAE grant table interface

[Steven Rostedt <srostedt@xxxxxxxxxx>]

It has been discovered that i386 boxes with more than 4G of RAM would 
randomly crash.  It was traced to the interface of blktap using 
gnttab_set_map_op.
It would pass in the 64 bit pte entry, but the gnttab_set_map_op would 
only take a 32 bit (on i386) unsigned long as a parameter. So we lose 
the top 32bits.
Luckily!  The kernel/HV ABI used a uint64_t as the variable to pass the 
address.  So this does *NOT* break the current kernel/HV ABI.
But after the HV grabs the 64 bit address from the guest, it too calls a 
function that uses a unsigned long (32bits on i386) to pass that address 
with.  So the HV side also chops off the top 64 bits of the variable.

This patch updates both the linux-2.6-sparse tree and the xen HV to use 
uint64_t instead of unsigned long for those particular functions.  This 
patch has been tested on RHEL5 Beta on a box with 12G i386.
Signed-off-by: Steven Rostedt <srostedt@xxxxxxxxxx>

diff -r 874cc0ff214d linux-2.6-xen-sparse/include/xen/gnttab.h
--- a/linux-2.6-xen-sparse/include/xen/gnttab.h Wed Nov 01 09:55:43 2006 +0000
+++ b/linux-2.6-xen-sparse/include/xen/gnttab.h Thu Nov 02 11:36:12 2006 -0500
@@ -118,7 +118,7 @@ int gnttab_resume(void);
 int gnttab_resume(void);
 
 static inline void
-gnttab_set_map_op(struct gnttab_map_grant_ref *map, unsigned long addr,
+gnttab_set_map_op(struct gnttab_map_grant_ref *map, uint64_t addr,
                  uint32_t flags, grant_ref_t ref, domid_t domid)
 {
        if (flags & GNTMAP_contains_pte)
@@ -134,7 +134,7 @@ gnttab_set_map_op(struct gnttab_map_gran
 }
 
 static inline void
-gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, unsigned long addr,
+gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, uint64_t addr,
                    uint32_t flags, grant_handle_t handle)
 {
        if (flags & GNTMAP_contains_pte)
diff -r 874cc0ff214d xen/arch/powerpc/mm.c
--- a/xen/arch/powerpc/mm.c     Wed Nov 01 09:55:43 2006 +0000
+++ b/xen/arch/powerpc/mm.c     Thu Nov 02 11:36:12 2006 -0500
@@ -43,14 +43,14 @@ unsigned long total_pages;
 unsigned long total_pages;
 
 int create_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags)
+    uint64_t addr, unsigned long frame, unsigned int flags)
 {
     panic("%s called\n", __func__);
     return 1;
 }
 
 int destroy_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags)
+    uint64_t addr, unsigned long frame, unsigned int flags)
 {
     panic("%s called\n", __func__);
     return 1;
diff -r 874cc0ff214d xen/arch/x86/mm.c
--- a/xen/arch/x86/mm.c Wed Nov 01 09:55:43 2006 +0000
+++ b/xen/arch/x86/mm.c Thu Nov 02 11:36:12 2006 -0500
@@ -2379,7 +2379,7 @@ int do_mmu_update(
 
 
 static int create_grant_pte_mapping(
-    unsigned long pte_addr, l1_pgentry_t nl1e, struct vcpu *v)
+    uint64_t pte_addr, l1_pgentry_t nl1e, struct vcpu *v)
 {
     int rc = GNTST_okay;
     void *va;
@@ -2403,7 +2403,7 @@ static int create_grant_pte_mapping(
     }
     
     va = map_domain_page(mfn);
-    va = (void *)((unsigned long)va + (pte_addr & ~PAGE_MASK));
+    va = (void *)((unsigned long)va + ((unsigned long)pte_addr & ~PAGE_MASK));
     page = mfn_to_page(mfn);
 
     type = page->u.inuse.type_info & PGT_type_mask;
@@ -2435,7 +2435,7 @@ static int create_grant_pte_mapping(
 }
 
 static int destroy_grant_pte_mapping(
-    unsigned long addr, unsigned long frame, struct domain *d)
+    uint64_t addr, unsigned long frame, struct domain *d)
 {
     int rc = GNTST_okay;
     void *va;
@@ -2454,7 +2454,7 @@ static int destroy_grant_pte_mapping(
     }
     
     va = map_domain_page(mfn);
-    va = (void *)((unsigned long)va + (addr & ~PAGE_MASK));
+    va = (void *)((unsigned long)va + ((unsigned long)addr & ~PAGE_MASK));
     page = mfn_to_page(mfn);
 
     type = page->u.inuse.type_info & PGT_type_mask;
@@ -2475,7 +2475,7 @@ static int destroy_grant_pte_mapping(
     /* Check that the virtual address supplied is actually mapped to frame. */
     if ( unlikely((l1e_get_intpte(ol1e) >> PAGE_SHIFT) != frame) )
     {
-        MEM_LOG("PTE entry %lx for address %lx doesn't match frame %lx",
+        MEM_LOG("PTE entry %lx for address %llx doesn't match frame %lx",
                 (unsigned long)l1e_get_intpte(ol1e), addr, frame);
         put_page_type(page);
         rc = GNTST_general_error;
@@ -2575,7 +2575,7 @@ static int destroy_grant_va_mapping(
 }
 
 int create_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags)
+    uint64_t addr, unsigned long frame, unsigned int flags)
 {
     l1_pgentry_t pte = l1e_from_pfn(frame, GRANT_PTE_FLAGS);
 
@@ -2590,7 +2590,7 @@ int create_grant_host_mapping(
 }
 
 int destroy_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags)
+    uint64_t addr, unsigned long frame, unsigned int flags)
 {
     if ( flags & GNTMAP_contains_pte )
         return destroy_grant_pte_mapping(addr, frame, current->domain);
diff -r 874cc0ff214d xen/include/asm-powerpc/grant_table.h
--- a/xen/include/asm-powerpc/grant_table.h     Wed Nov 01 09:55:43 2006 +0000
+++ b/xen/include/asm-powerpc/grant_table.h     Thu Nov 02 11:36:12 2006 -0500
@@ -30,9 +30,9 @@
  * must hold a reference to the page.
  */
 int create_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags);
+    uint64_t addr, unsigned long frame, unsigned int flags);
 int destroy_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags);
+    uint64_t addr, unsigned long frame, unsigned int flags);
 
 #define gnttab_create_shared_page(d, t, i)                               \
     do {                                                                 \
diff -r 874cc0ff214d xen/include/asm-x86/grant_table.h
--- a/xen/include/asm-x86/grant_table.h Wed Nov 01 09:55:43 2006 +0000
+++ b/xen/include/asm-x86/grant_table.h Thu Nov 02 11:36:12 2006 -0500
@@ -14,9 +14,9 @@
  * must hold a reference to the page.
  */
 int create_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags);
+    uint64_t addr, unsigned long frame, unsigned int flags);
 int destroy_grant_host_mapping(
-    unsigned long addr, unsigned long frame, unsigned int flags);
+    uint64_t addr, unsigned long frame, unsigned int flags);
 
 #define gnttab_create_shared_page(d, t, i)                               \
     do {                                                                 \

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