lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 1 Nov 2007 18:02:06 +0100
From:	"Andreas Herrmann" <andreas.herrmann3@....com>
To:	linux-kernel@...r.kernel.org, mingo@...e.hu, tglx@...utronix.de
cc:	akpm@...ux-foundation.org, gcosta@...hat.com, travis@....com
Subject: [PATCH] x86: show cpuinfo only for online CPUs

This patch applies on current Linus' git with Glauber's recent cpuinfo fix
(http://marc.info/?l=linux-kernel&m=119392088227245) applied.


Regards,

Andreas

-- 
[PATCH] x86: show cpuinfo only for online CPUs

Fix regressions introduced with 92cb7612aee39642d109b8d935ad265e602c0563.

It can happen that cpuinfo is displayed for CPUs that are not online or
even worse for CPUs not present at all. As an example, following was
shown for a "second" CPU of a single core K8 variant:

    processor       : 0
    vendor_id       : unknown
    cpu family      : 0
    model           : 0
    model name      : unknown
    stepping        : 0
    cache size      : 0 KB
    fpu             : yes
    fpu_exception   : yes
    cpuid level     : 0
    wp              : yes
    flags           :
    bogomips        : 0.00
    clflush size    : 0
    cache_alignment : 0
    address sizes   : 0 bits physical, 0 bits virtual
    power management:

Signed-off-by: Andreas Herrmann <andreas.herrmann3@....com>
---
 arch/x86/kernel/cpu/proc.c |   13 ++++---------
 arch/x86/kernel/setup_64.c |   15 ++++-----------
 2 files changed, 8 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
index 066f8c6..13cfd85 100644
--- a/arch/x86/kernel/cpu/proc.c
+++ b/arch/x86/kernel/cpu/proc.c
@@ -85,14 +85,9 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		/* nothing */
 	};
 	struct cpuinfo_x86 *c = v;
-	int i, n = 0;
+	int i, n = c->cpu_index;
 	int fpu_exception;
 
-#ifdef CONFIG_SMP
-	if (!cpu_online(n))
-		return 0;
-	n = c->cpu_index;
-#endif
 	seq_printf(m, "processor\t: %d\n"
 		"vendor_id\t: %s\n"
 		"cpu family\t: %d\n"
@@ -177,14 +172,14 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 static void *c_start(struct seq_file *m, loff_t *pos)
 {
 	if (*pos == 0)	/* just in case, cpu 0 is not the first */
-		*pos = first_cpu(cpu_possible_map);
-	if ((*pos) < NR_CPUS && cpu_possible(*pos))
+		*pos = first_cpu(cpu_online_map);
+	if ((*pos) < NR_CPUS && cpu_online(*pos))
 		return &cpu_data(*pos);
 	return NULL;
 }
 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	*pos = next_cpu(*pos, cpu_possible_map);
+	*pos = next_cpu(*pos, cpu_online_map);
 	return c_start(m, pos);
 }
 static void c_stop(struct seq_file *m, void *v)
diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
index ec59fcb..480230a 100644
--- a/arch/x86/kernel/setup_64.c
+++ b/arch/x86/kernel/setup_64.c
@@ -998,7 +998,7 @@ void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
 static int show_cpuinfo(struct seq_file *m, void *v)
 {
 	struct cpuinfo_x86 *c = v;
-	int cpu = 0;
+	int cpu = c->cpu_index;
 
 	/* 
 	 * These flag bits must match the definitions in <asm/cpufeature.h>.
@@ -1075,13 +1075,6 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		/* nothing */
 	};
 
-
-#ifdef CONFIG_SMP
-	if (!cpu_online(c->cpu_index))
-		return 0;
-	cpu = c->cpu_index;
-#endif
-
 	seq_printf(m,"processor\t: %u\n"
 		     "vendor_id\t: %s\n"
 		     "cpu family\t: %d\n"
@@ -1170,15 +1163,15 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 static void *c_start(struct seq_file *m, loff_t *pos)
 {
 	if (*pos == 0)	/* just in case, cpu 0 is not the first */
-		*pos = first_cpu(cpu_possible_map);
-	if ((*pos) < NR_CPUS && cpu_possible(*pos))
+		*pos = first_cpu(cpu_online_map);
+	if ((*pos) < NR_CPUS && cpu_online(*pos))
 		return &cpu_data(*pos);
 	return NULL;
 }
 
 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 {
-	*pos = next_cpu(*pos, cpu_possible_map);
+	*pos = next_cpu(*pos, cpu_online_map);
 	return c_start(m, pos);
 }
 
-- 
1.5.3.4





-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ