[PATCH] - Fix get_model_name() for mixed cpu type systems

Jack Steiner
2006-10-19T14:08:57Z

If a system consists of mixed processor types, kmalloc()
can be called before the per-cpu data page is initialized.
If the slab contains sufficient memory, then kmalloc() works
ok. However, if the slabs are empty, slab calls the memory
allocator. This requires per-cpu data (NODE_DATA()) & the
cpu dies.

Signed-off-by: Jack Steiner <steiner@sgi.com>

---
You are right! "BUG" is a little harsh. I changed the code to print
a "table overflow" message & return "Unknown".

Index: linux/arch/ia64/kernel/setup.c
=================================--- linux.orig/arch/ia64/kernel/setup.c 2006-10-18 15:49:49.000000000 -0500
+++ linux/arch/ia64/kernel/setup.c 2006-10-19 09:05:44.108673017 -0500
@@ -643,12 +643,15 @@ struct seq_operations cpuinfo_op = {
.show = show_cpuinfo
};

-static char brandname[128];
+#define MAX_BRANDS 8
+static char brandname[MAX_BRANDS][128];

static char * __cpuinit
get_model_name(__u8 family, __u8 model)
{
+ static int overflow;
char brand[128];
+ int i;

if (ia64_pal_get_brand_info(brand)) {
if (family = 0x7)
@@ -660,12 +663,17 @@ get_model_name(__u8 family, __u8 model)
} else
memcpy(brand, "Unknown", 8);
}
- if (brandname[0] = '\0')
- return strcpy(brandname, brand);
- else if (strcmp(brandname, brand) = 0)
- return brandname;
- else
- return kstrdup(brand, GFP_KERNEL);
+ for (i = 0; i < MAX_BRANDS; i++)
+ if (strcmp(brandname[i], brand) = 0)
+ return brandname[i];
+ for (i = 0; i < MAX_BRANDS; i++)
+ if (brandname[i][0] = '\0')
+ return strcpy(brandname[i], brand);
+ if (overflow++ = 0)
+ printk(KERN_ERR
+ "%s: Table overflow. Some processor model information will be missing\n",
+ __FUNCTION__);
+ return "Unknown";
}

static void __cpuinit