[Xen-devel] [PATCH] Fix to xenoprof in compat mode

[George Dunlap <George.Dunlap@xxxxxxxxxxxxx>]

The attached patch fixes xenoprof in compat mode (32-bit guest on a 
64-bit hypervisor).  Although xen/common/xenoprof.c uses the compat 
structure sizes, xen/arch/x86/oprofile/xenoprof.c does not.  The 
structures look the same, but the compat mode structure is packed, 
whereas the non-compat version has 64-bit values 64-bit aligned.  The 
result was that the performance counters are not properly set, and no 
trace events are generated.
The attached patch adds a function called compat_oprof_arch_counter() in 
xen/arch/x86/oprofile/xenoprof.c, which uses the correctly-sized 
structure.  In xen/common/compat/xenoprof.c, it adds a #define such that 
the compat version of do_xenoprof_op() will call the proper version.
-George

diff -r 26d236e3a6ea xen/arch/x86/oprofile/xenoprof.c
--- a/xen/arch/x86/oprofile/xenoprof.c  Tue Feb 19 14:16:09 2008 +0000
+++ b/xen/arch/x86/oprofile/xenoprof.c  Thu Feb 21 11:12:04 2008 +0000
@@ -11,6 +11,9 @@
 #include <xen/guest_access.h>
 #include <xen/sched.h>
 #include <public/xenoprof.h>
+#ifdef CONFIG_COMPAT
+#include <compat/xenoprof.h>
+#endif
 #include <asm/hvm/support.h>
 
 #include "op_counter.h"
@@ -35,6 +38,28 @@ int xenoprof_arch_counter(XEN_GUEST_HAND
     return 0;
 }
 
+#ifdef CONFIG_COMPAT
+int compat_oprof_arch_counter(XEN_GUEST_HANDLE(void) arg)
+{
+    struct compat_oprof_counter counter;
+
+    if ( copy_from_guest(&counter, arg, 1) )
+        return -EFAULT;
+
+    if ( counter.ind > OP_MAX_COUNTER )
+        return -E2BIG;
+
+    counter_config[counter.ind].count     = counter.count;
+    counter_config[counter.ind].enabled   = counter.enabled;
+    counter_config[counter.ind].event     = counter.event;
+    counter_config[counter.ind].kernel    = counter.kernel;
+    counter_config[counter.ind].user      = counter.user;
+    counter_config[counter.ind].unit_mask = counter.unit_mask;
+
+    return 0;
+}
+#endif
+
 int xenoprofile_get_mode(struct vcpu *v, struct cpu_user_regs * const regs)
 {
     if ( !guest_mode(regs) )
diff -r 26d236e3a6ea xen/common/compat/xenoprof.c
--- a/xen/common/compat/xenoprof.c      Tue Feb 19 14:16:09 2008 +0000
+++ b/xen/common/compat/xenoprof.c      Tue Feb 19 14:44:38 2008 +0000
@@ -14,6 +14,7 @@ CHECK_oprof_init;
 
 #define xenoprof_get_buffer compat_oprof_get_buffer
 #define xenoprof_op_get_buffer compat_oprof_op_get_buffer
+#define xenoprof_arch_counter compat_oprof_arch_counter
 
 #define xen_domid_t domid_t
 #define compat_domid_t domid_compat_t
diff -r 26d236e3a6ea xen/include/asm-x86/xenoprof.h
--- a/xen/include/asm-x86/xenoprof.h    Tue Feb 19 14:16:09 2008 +0000
+++ b/xen/include/asm-x86/xenoprof.h    Tue Feb 19 14:47:34 2008 +0000
@@ -41,6 +41,7 @@ int xenoprof_arch_init(int *num_events, 
 #define xenoprof_arch_release_counters()        nmi_release_counters()
 
 int xenoprof_arch_counter(XEN_GUEST_HANDLE(void) arg);
+int compat_oprof_arch_counter(XEN_GUEST_HANDLE(void) arg);
 
 struct vcpu;
 struct cpu_user_regs;

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel