x86/cpu: Change type of x86_cache_size variable to unsigned int

Currently, x86_cache_size is of type int, which makes no sense as we
will never have a valid cache size equal or less than 0. So instead of
initializing this variable to -1, it can perfectly be initialized to 0
and use it as an unsigned variable instead.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Addresses-Coverity-ID: 1464429
Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index b7c8583..44c2c4e 100644 (file)
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -109,7 +109,7 @@ struct cpuinfo_x86 {
        char                    x86_vendor_id[16];
        char                    x86_model_id[64];
        /* in KB - valid for CPUS which support this call: */
-       int                     x86_cache_size;
+       unsigned int            x86_cache_size;
        int                     x86_cache_alignment;    /* In bytes */
        /* Cache QoS architectural values: */
        int                     x86_cache_max_rmid;     /* max index */

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index a7d8df6..824aee0 100644 (file)
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1184,7 +1184,7 @@ static void identify_cpu(struct cpuinfo_x86 *c)
        int i;
 
        c->loops_per_jiffy = loops_per_jiffy;
-       c->x86_cache_size = -1;
+       c->x86_cache_size = 0;
        c->x86_vendor = X86_VENDOR_UNKNOWN;
        c->x86_model = c->x86_stepping = 0;     /* So far unknown... */
        c->x86_vendor_id[0] = '\0'; /* Unset */

diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index b94279b..a15db2b 100644 (file)
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -982,7 +982,7 @@ static struct microcode_ops microcode_intel_ops = {
 
 static int __init calc_llc_size_per_core(struct cpuinfo_x86 *c)
 {
-       u64 llc_size = c->x86_cache_size * 1024;
+       u64 llc_size = c->x86_cache_size * 1024ULL;
 
        do_div(llc_size, c->x86_max_cores);
 

diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
index ee4cc38..2c8522a 100644 (file)
--- a/arch/x86/kernel/cpu/proc.c
+++ b/arch/x86/kernel/cpu/proc.c
@@ -91,8 +91,8 @@ static int show_cpuinfo(struct seq_file *m, void *v)
        }
 
        /* Cache size */
-       if (c->x86_cache_size >= 0)
-               seq_printf(m, "cache size\t: %d KB\n", c->x86_cache_size);
+       if (c->x86_cache_size)
+               seq_printf(m, "cache size\t: %u KB\n", c->x86_cache_size);
 
        show_cpuinfo_core(m, c, cpu);
        show_cpuinfo_misc(m, c);