x86: sim: Make 32 bit x86 processes work again.

When the LiveProcess class was renamed to be just Process, the CL author
also changed the syscall function from a virtual function into a regular
one. Unfortunately, the I386Process class overrode the syscall function
to adjust the return address so that control would return to the right
place. Without that adjustment, 32 bit x86 process would segfault and die
immediately after their first system call.

This change reinstates the virtual specifier on the base syscall function,
and adds an override keyword on the I386Process's version so that it won't
be orphaned again in the future. It also fixes some small style issues the
style checker script complained about.

Change-Id: I0d1178ea0eda6676050c8fc043820a2bb4d99c0d
Reviewed-on: https://gem5-review.googlesource.com/3500
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

diff --git a/src/arch/x86/process.hh b/src/arch/x86/process.hh
index 4240ee625a456133811b4decb1bf0b51ded320a9..fe3134844151df1f86dfd785fda10bbad9ffd57f 100644 (file)
--- a/src/arch/x86/process.hh
+++ b/src/arch/x86/process.hh
@@ -43,9 +43,9 @@
 #include <string>
 #include <vector>
 
+#include "mem/multi_level_page_table.hh"
 #include "sim/aux_vector.hh"
 #include "sim/process.hh"
-#include "mem/multi_level_page_table.hh"
 
 class SyscallDesc;
 
@@ -175,7 +175,8 @@ namespace X86ISA
         void argsInit(int pageSize);
         void initState();
 
-        void syscall(int64_t callnum, ThreadContext *tc, Fault *fault);
+        void syscall(int64_t callnum, ThreadContext *tc,
+                     Fault *fault) override;
         X86ISA::IntReg getSyscallArg(ThreadContext *tc, int &i);
         X86ISA::IntReg getSyscallArg(ThreadContext *tc, int &i, int width);
         void setSyscallArg(ThreadContext *tc, int i, X86ISA::IntReg val);
@@ -186,7 +187,8 @@ namespace X86ISA
     /**
      * Declaration of architectural page table for x86.
      *
-     * These page tables are stored in system memory and respect x86 specification.
+     * These page tables are stored in system memory and respect x86
+     * specification.
      */
     typedef MultiLevelPageTable<PageTableOps> ArchPageTable;
 

diff --git a/src/sim/process.hh b/src/sim/process.hh
index add3eb357921f3156eb7e4fb724bd7a9478d78f8..5da30a4c3ad23b00470f49ae7731d6d21e90ae84 100644 (file)
--- a/src/sim/process.hh
+++ b/src/sim/process.hh
@@ -71,7 +71,7 @@ class Process : public SimObject
     void initState() override;
     DrainState drain() override;
 
-    void syscall(int64_t callnum, ThreadContext *tc, Fault *fault);
+    virtual void syscall(int64_t callnum, ThreadContext *tc, Fault *fault);
     virtual TheISA::IntReg getSyscallArg(ThreadContext *tc, int &i) = 0;
     virtual TheISA::IntReg getSyscallArg(ThreadContext *tc, int &i, int width);
     virtual void setSyscallArg(ThreadContext *tc, int i,