if PIE is enabled, switch the paravirt assembly constraints to be
compatible. The %c/i constrains generate smaller code so is kept by
default.

Position Independent Executable (PIE) support will allow to extended the
KASLR randomization range below the -2G memory limit.

Signed-off-by: Thomas Garnier <thgar...@google.com>
---
 arch/x86/include/asm/paravirt_types.h | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/paravirt_types.h 
b/arch/x86/include/asm/paravirt_types.h
index 180bc0bff0fb..140747a98d94 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -337,9 +337,17 @@ extern struct pv_lock_ops pv_lock_ops;
 #define PARAVIRT_PATCH(x)                                      \
        (offsetof(struct paravirt_patch_template, x) / sizeof(void *))
 
+#ifdef CONFIG_X86_PIE
+#define paravirt_opptr_call "a"
+#define paravirt_opptr_type "p"
+#else
+#define paravirt_opptr_call "c"
+#define paravirt_opptr_type "i"
+#endif
+
 #define paravirt_type(op)                              \
        [paravirt_typenum] "i" (PARAVIRT_PATCH(op)),    \
-       [paravirt_opptr] "i" (&(op))
+       [paravirt_opptr] paravirt_opptr_type (&(op))
 #define paravirt_clobber(clobber)              \
        [paravirt_clobber] "i" (clobber)
 
@@ -395,7 +403,7 @@ int paravirt_disable_iospace(void);
  */
 #define PARAVIRT_CALL                                  \
        ANNOTATE_RETPOLINE_SAFE                         \
-       "call *%c[paravirt_opptr];"
+       "call *%" paravirt_opptr_call "[paravirt_opptr];"
 
 /*
  * These macros are intended to wrap calls through one of the paravirt
-- 
2.16.2.660.g709887971b-goog

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