If a PVOP call macro is inlined at the beginning of a function, gcc can
insert the call instruction before setting up a stack frame, which
breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled and
can result in a bad stack trace.

Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
listing the stack pointer as an output operand for the PVOP inline asm
statements.

Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com>
Cc: Jeremy Fitzhardinge <jer...@goop.org>
Cc: Chris Wright <chr...@sous-sol.org>
Cc: Alok Kataria <akata...@vmware.com>
Cc: Rusty Russell <ru...@rustcorp.com.au>
---
 arch/x86/include/asm/paravirt_types.h | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/paravirt_types.h 
b/arch/x86/include/asm/paravirt_types.h
index ce029e4..1812294 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -497,8 +497,9 @@ int paravirt_disable_iospace(void);
  * makes sure the incoming and outgoing types are always correct.
  */
 #ifdef CONFIG_X86_32
-#define PVOP_VCALL_ARGS                                \
-       unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx
+#define PVOP_VCALL_ARGS                                                        
\
+       unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx;      \
+       register void *__sp asm("esp")
 #define PVOP_CALL_ARGS                 PVOP_VCALL_ARGS
 
 #define PVOP_CALL_ARG1(x)              "a" ((unsigned long)(x))
@@ -516,9 +517,10 @@ int paravirt_disable_iospace(void);
 #define VEXTRA_CLOBBERS
 #else  /* CONFIG_X86_64 */
 /* [re]ax isn't an arg, but the return val */
-#define PVOP_VCALL_ARGS                                        \
-       unsigned long __edi = __edi, __esi = __esi,     \
-               __edx = __edx, __ecx = __ecx, __eax = __eax
+#define PVOP_VCALL_ARGS                                                \
+       unsigned long __edi = __edi, __esi = __esi,             \
+               __edx = __edx, __ecx = __ecx, __eax = __eax;    \
+       register void *__sp asm("rsp")
 #define PVOP_CALL_ARGS         PVOP_VCALL_ARGS
 
 #define PVOP_CALL_ARG1(x)              "D" ((unsigned long)(x))
@@ -557,7 +559,7 @@ int paravirt_disable_iospace(void);
                        asm volatile(pre                                \
                                     paravirt_alt(PARAVIRT_CALL)        \
                                     post                               \
-                                    : call_clbr                        \
+                                    : "+r" (__sp), call_clbr           \
                                     : paravirt_type(op),               \
                                       paravirt_clobber(clbr),          \
                                       ##__VA_ARGS__                    \
@@ -567,7 +569,7 @@ int paravirt_disable_iospace(void);
                        asm volatile(pre                                \
                                     paravirt_alt(PARAVIRT_CALL)        \
                                     post                               \
-                                    : call_clbr                        \
+                                    : "+r" (__sp), call_clbr           \
                                     : paravirt_type(op),               \
                                       paravirt_clobber(clbr),          \
                                       ##__VA_ARGS__                    \
@@ -594,7 +596,7 @@ int paravirt_disable_iospace(void);
                asm volatile(pre                                        \
                             paravirt_alt(PARAVIRT_CALL)                \
                             post                                       \
-                            : call_clbr                                \
+                            : "+r" (__sp), call_clbr                   \
                             : paravirt_type(op),                       \
                               paravirt_clobber(clbr),                  \
                               ##__VA_ARGS__                            \
-- 
2.4.3

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