[Xen-devel] [PATCH v2 5/6] x86_emulate: Remove dependency on __LINE__ for release builds

[Ross Lagerwall <ross.lagerwall@xxxxxxxxxx>]

When using LivePatch, use of __LINE__ can generate spurious changes in
functions due to embedded line numbers.  For release builds with
LivePatch enabled, remove the use of these line numbers and print the
current text address instead.

Signed-off-by: Ross Lagerwall <ross.lagerwall@xxxxxxxxxx>
---
 xen/arch/x86/x86_emulate/x86_emulate.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/x86_emulate/x86_emulate.c 
b/xen/arch/x86/x86_emulate/x86_emulate.c
index 613648e..cf05544 100644
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -776,6 +776,22 @@ do{ asm volatile (                                         
             \
 #define __emulate_1op_8byte(_op, _dst, _eflags)
 #endif /* __i386__ */
 
+#if defined(NDEBUG) && defined(CONFIG_LIVEPATCH)
+#define invoke_stub_exception(trapnr, ec)                                   \
+    do {                                                                    \
+        gprintk(XENLOG_WARNING,                                             \
+                "exception %u (ec=%04x) in emulation stub (address %pS)\n", \
+                trapnr, ec, current_text_addr());                           \
+    } while (0)
+#else
+#define invoke_stub_exception(trapnr, ec)                                   \
+    do {                                                                    \
+        gprintk(XENLOG_WARNING,                                             \
+                "exception %u (ec=%04x) in emulation stub (line %u)\n",     \
+                trapnr, ec, __LINE__);                                      \
+    } while (0)
+#endif
+
 #ifdef __XEN__
 # define invoke_stub(pre, post, constraints...) do {                    \
     union stub_exception_token res_ = { .raw = ~0 };                    \
@@ -791,9 +807,7 @@ do{ asm volatile (                                          
            \
                      [stub] "rm" (stub.func) );                         \
     if ( unlikely(~res_.raw) )                                          \
     {                                                                   \
-        gprintk(XENLOG_WARNING,                                         \
-                "exception %u (ec=%04x) in emulation stub (line %u)\n", \
-                res_.fields.trapnr, res_.fields.ec, __LINE__);          \
+        invoke_stub_exception(res_.fields.trapnr, res_.fields.ec);      \
         gprintk(XENLOG_INFO, "stub: %"__stringify(MAX_INST_LEN)"ph\n",  \
                 stub.func);                                             \
         generate_exception_if(res_.fields.trapnr == EXC_UD, EXC_UD);    \
-- 
2.7.4


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