x86, asmlinkage, lguest: Pass in globals into assembler statement
authorAndi Kleen <ak@linux.intel.com>
Tue, 5 Nov 2013 10:52:28 +0000 (21:22 +1030)
committerRusty Russell <rusty@rustcorp.com.au>
Thu, 7 Nov 2013 01:43:05 +0000 (12:13 +1030)
Tell the compiler that the inline assembler statement
references lguest_entry.

This fixes compile problems with LTO where the variable
and the assembler code may end up in different files.

Cc: x86@kernel.org
Cc: rusty@rustcorp.com.au
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
drivers/lguest/x86/core.c

index 5169239..922a1ac 100644 (file)
@@ -157,7 +157,7 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages)
         * stack, then the address of this call.  This stack layout happens to
         * exactly match the stack layout created by an interrupt...
         */
-       asm volatile("pushf; lcall *lguest_entry"
+       asm volatile("pushf; lcall *%4"
                     /*
                      * This is how we tell GCC that %eax ("a") and %ebx ("b")
                      * are changed by this routine.  The "=" means output.
@@ -169,7 +169,9 @@ static void run_guest_once(struct lg_cpu *cpu, struct lguest_pages *pages)
                      * physical address of the Guest's top-level page
                      * directory.
                      */
-                    : "0"(pages), "1"(__pa(cpu->lg->pgdirs[cpu->cpu_pgd].pgdir))
+                    : "0"(pages), 
+                      "1"(__pa(cpu->lg->pgdirs[cpu->cpu_pgd].pgdir)),
+                      "m"(lguest_entry)
                     /*
                      * We tell gcc that all these registers could change,
                      * which means we don't have to save and restore them in