Restore 2.4 MTRR feature.

PATCH [email protected] 1 participant 1 message Jan 23, 2004

lore

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lore

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2004-01-23 06:38 UTC #0 lore raw

If the CPU doesn't support MTRRs, don't create a /proc/mtrr

Dave

arch/i386/kernel/cpu/mtrr/if.c +8 -0

diff -urpN --exclude-from=/home/davej/.exclude bk-linus/arch/i386/kernel/cpu/mtrr/if.c linux-2.5/arch/i386/kernel/cpu/mtrr/if.c
@@ -352,6 +352,14 @@ static int mtrr_seq_show(struct seq_file
 
 static int __init mtrr_if_init(void)
 {
+	struct cpuinfo_x86 *c = &boot_cpu_data;
+
+	if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
+		(!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
+		(!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
+		(!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
+	return -ENODEV;
+
 	proc_root_mtrr =
 	    create_proc_entry("mtrr", S_IWUSR | S_IRUGO, &proc_root);
 	if (proc_root_mtrr) {