[PATCH] kdb: add rdmsr and wrmsr commands for i386

[Bernardo Innocenti]

The syntax is:
   rdmsr <addr>
   wrmsr <addr> <l> <h>

Signed-off-by: Bernardo Innocenti <bernie at codewiz.org>


diff --git a/arch/i386/kdb/kdbasupport.c b/arch/i386/kdb/kdbasupport.c
index 482b319..8ecef2e 100644
--- a/arch/i386/kdb/kdbasupport.c
+++ b/arch/i386/kdb/kdbasupport.c
@@ -223,6 +223,47 @@ kdba_removedbreg(kdb_bp_t *bp)
  	kdba_putdr7(dr7);
  }

+static int
+kdba_rdmsr(int argc, const char **argv)
+{
+	unsigned long addr;
+	uint64_t val;
+	int diag;
+
+	if (argc != 1) {
+		return KDB_ARGCOUNT;
+	}
+
+	if ((diag = kdbgetularg(argv[1], &addr)))
+		return diag;
+
+	kdb_printf("msr(0x%lx) = ", addr);
+	rdmsrl(addr, val);
+	kdb_printf("0x%llx\n", val);
+
+	return 0;
+}
+
+static int
+kdba_wrmsr(int argc, const char **argv)
+{
+	unsigned long addr;
+	unsigned long l, h;
+	int diag;
+
+	if (argc != 3)
+		return KDB_ARGCOUNT;
+
+	if ((diag = kdbgetularg(argv[1], &addr))
+			|| (diag = kdbgetularg(argv[2], &l))
+			|| (diag = kdbgetularg(argv[3], &h)))
+		return diag;
+
+	wrmsr(addr, l, h);
+
+	return 0;
+}
+

  /*
   * kdba_getregcontents
@@ -474,12 +515,11 @@ kdba_setregcontents(const char *regname,
   *	argument is NULL (struct pt_regs).   The alternate register
   *	set types supported by this function:
   *
- *	d 		Debug registers
+ *	d		Debug registers
   *	c		Control registers
   *	u		User registers at most recent entry to kernel
   *			for the process currently selected with "pid" command.
   * Following not yet implemented:
- *	m		Model Specific Registers (extra defines register #)
   *	r		Memory Type Range Registers (extra defines register)
   */

@@ -546,8 +586,6 @@ kdba_dumpregs(struct pt_regs *regs,
  			   cr[0], cr[1], cr[2], cr[3], cr[4]);
  		return 0;
  	}
-	case 'm':
-		break;
  	case 'r':
  		break;
  	default:
@@ -899,6 +937,9 @@ kdba_init(void)
  {
  	kdb_register("pt_regs", kdba_pt_regs, "address", "Format struct 
pt_regs", 0);
  	kdb_register("stackdepth", kdba_stackdepth, "[percentage]", "Print 
processes using >= stack percentage", 0);
+	//TODO: maybe check CPUID first
+	kdb_register("rdmsr", kdba_rdmsr, "<maddr>", "Display Model Specific 
Register", 0);
+	kdb_register("wrmsr", kdba_wrmsr, "<maddr> <l> <h>", "Modify Model 
Specific Register", 0);

  	return;
  }
diff --git a/kdb/kdbmain.c b/kdb/kdbmain.c
index 0b2cb91..88bf14f 100644
--- a/kdb/kdbmain.c
+++ b/kdb/kdbmain.c
@@ -2596,8 +2596,7 @@ kdb_rd(int argc, const char **argv)
   *	none.
   * Remarks:
   *	Currently doesn't allow modification of control or
- *	debug registers, nor does it allow modification
- *	of model-specific registers (MSR).
+ *	debug registers.
   */

  static int


-- 
    // Bernardo Innocenti
  \X/  http://www.codewiz.org/