[Qemu-devel] [PATCH v3] target-i386: Fix segment cache dump

[Tobias Markus <tobias@markus-regensburg.de>]

When in Long Mode, cpu_x86_seg_cache() logs "DS16" because the Default
operation size bit (D/B bit) is not set for Long Mode Data Segments since
there are only Data Segments in Long Mode and no explicit 16/32/64-bit
Descriptors.
This patch fixes this by checking the Long Mode Active bit of the hidden
flags variable and logging "DS" if it is set. (I.e. in Long Mode all Data
Segments are logged as "DS")

Signed-off-by: Tobias Markus <tobias@markus-regensburg.de>
---
v3: * Manually Break Lines
    * Again change line wrapping as suggested by Eric Blake
v2: * Fix line wrapping as suggested in IRC
    * Break the line
Note that alternatively, Data Segments in Long Mode could be logged as "DS64" to avoid confusion about the missing 64 postfix. (But that would be, strictly speaking, wrong because there are only DSs and no DS16/32/64 in Long Mode.)
PS: This is my first contribution to an Open Source Project and I would be very happy about constructive feedback, especially about possible wrong line wrapping.
  target-i386/helper.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/target-i386/helper.c b/target-i386/helper.c
index bf3e2ac..0edb93b 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -147,7 +147,9 @@ cpu_x86_dump_seg_cache(CPUX86State *env, FILE *f, fprintf_function cpu_fprintf,
             cpu_fprintf(f, " [%c%c", (sc->flags & DESC_C_MASK) ? 'C' : '-',
                         (sc->flags & DESC_R_MASK) ? 'R' : '-');
         } else {
-            cpu_fprintf(f, (sc->flags & DESC_B_MASK) ? "DS  " : "DS16");
+            cpu_fprintf(f,
+                        (sc->flags & DESC_B_MASK || env->hflags & HF_LMA_MASK)
+                        ? "DS  " : "DS16");
             cpu_fprintf(f, " [%c%c", (sc->flags & DESC_E_MASK) ? 'E' : '-',
                         (sc->flags & DESC_W_MASK) ? 'W' : '-');
         }
-- 
1.8.4