[PATCH] powerpc/pseries: misc lparcfg fixes

This fixes several problems with the lparcfg code.  In case
someone gets a sense of deja-vu, part of this was submitted last Sep, I
thought the changes went in, but either got backed out, or just got
lost.

First, change the local_buffer declaration to be unsigned char *.  We
had a bad-math problem in a 2.4 tree which was built with a
"-fsigned-char" parm.  I dont believe we ever build with that parm
now-a-days, but to be safe, I'd prefer the declaration be explicit.

Second, fix a bad math calculation for splpar_strlen.

Third, on the rtas_call for get-system-parameter, pass in
RTAS_DATA_BUF_SIZE for the rtas_data_buf size, instead of letting random
data determine the size.   Until recently, we've had a sufficiently
large 'random data' value get passed in, so the function just happens to
have worked OK.   Now it's getting passed a '0', which causes the
rtas_call to return success, but no data shows up in the buffer.
(oops!).   This was found by the LTC test org.

This is in a branch of code that only gets run on SPLPAR systems.
Tested on power5 Lpar.

Signed-off-by: Will Schmidt <willschm@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/lparcfg.c b/arch/powerpc/kernel/lparcfg.c
index 8be687700a50..2cbde865d4f5 100644
--- a/arch/powerpc/kernel/lparcfg.c
+++ b/arch/powerpc/kernel/lparcfg.c
@@ -37,7 +37,7 @@
 #include <asm/prom.h>
 #include <asm/vdso_datapage.h>
 
-#define MODULE_VERS "1.6"
+#define MODULE_VERS "1.7"
 #define MODULE_NAME "lparcfg"
 
 /* #define LPARCFG_DEBUG */
@@ -242,7 +242,7 @@ static void parse_system_parameter_string(struct seq_file *m)
 {
         int call_status;
 
-        char *local_buffer = kmalloc(SPLPAR_MAXLENGTH, GFP_KERNEL);
+        unsigned char *local_buffer = kmalloc(SPLPAR_MAXLENGTH, GFP_KERNEL);
         if (!local_buffer) {
                 printk(KERN_ERR "%s %s kmalloc failure at line %d \n",
                        __FILE__, __FUNCTION__, __LINE__);
@@ -254,7 +254,8 @@ static void parse_system_parameter_string(struct seq_file *m)
         call_status = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1,
                                 NULL,
                                 SPLPAR_CHARACTERISTICS_TOKEN,
-                                __pa(rtas_data_buf));
+                                __pa(rtas_data_buf),
+                                RTAS_DATA_BUF_SIZE);
         memcpy(local_buffer, rtas_data_buf, SPLPAR_MAXLENGTH);
         spin_unlock(&rtas_data_buf_lock);
 
@@ -275,7 +276,7 @@ static void parse_system_parameter_string(struct seq_file *m)
 #ifdef LPARCFG_DEBUG
                 printk(KERN_INFO "success calling get-system-parameter \n");
 #endif
-                splpar_strlen = local_buffer[0] * 16 + local_buffer[1];
+                splpar_strlen = local_buffer[0] * 256 + local_buffer[1];
                 local_buffer += 2;      /* step over strlen value */
 
                 memset(workbuffer, 0, SPLPAR_MAXLENGTH);