Hi Linus,
I made these changes:
a) removed if(!capable()) check from write() method as it breaks the
classical UNIX philosophy (if a process had enough privilege to open
a file it does not matter what privilege he has at the time of
writing, it may have received a descriptor from some other privileged
"open file" server)
b) general cleanup of messages, priorities, dropped CONFIG_M686 check
etc.
c) implemented read() method and the size for /proc/driver/microcode
file. If the update has taken place the size is adjusted to
smp_num_cpus*sizeof(struct microcode) and the file contains the binary
form of the actual microcode data (last successfuly) written.
http://www.ocston.org/~tigran/patches/microcode/microcode-2.3.47-p3.patch
Regards,
------
Tigran A. Aivazian | http://www.sco.com
Escalations Research Group | tel: +44-(0)1923-813796
Santa Cruz Operation Ltd | http://www.ocston.org/~tigran
diff -urN -X dontdiff linux/arch/i386/config.in linux-mc/arch/i386/config.in
--- linux/arch/i386/config.in Wed Feb 16 22:36:52 2000
+++ linux-mc/arch/i386/config.in Fri Feb 18 06:54:32 2000
@@ -49,7 +49,7 @@
define_bool CONFIG_X86_USE_3DNOW y
fi
-if [ "$CONFIG_M686" = "y" -a "$CONFIG_PROC_FS" = "y" ]; then
+if [ "$CONFIG_PROC_FS" = "y" ]; then
tristate '/proc/driver/microcode - Intel P6 CPU microcode support' CONFIG_MICROCODE
fi
diff -urN -X dontdiff linux/arch/i386/kernel/microcode.c linux-mc/arch/i386/kernel/microcode.c
--- linux/arch/i386/kernel/microcode.c Wed Feb 16 22:39:53 2000
+++ linux-mc/arch/i386/kernel/microcode.c Fri Feb 18 08:11:04 2000
@@ -18,6 +18,8 @@
*
* 1.0 16 February 2000, Tigran Aivazian <tigran@sco.com>
* Initial release.
+ * 1.01 18 February 2000, Tigran Aivazian <tigran@sco.com>
+ * Added read() support + cleanups.
*/
#include <linux/init.h>
@@ -31,7 +33,7 @@
#include <asm/uaccess.h>
#include <asm/processor.h>
-#define MICROCODE_VERSION "1.0"
+#define MICROCODE_VERSION "1.01"
MODULE_DESCRIPTION("CPU (P6) microcode update driver");
MODULE_AUTHOR("Tigran Aivazian <tigran@ocston.org>");
@@ -40,11 +42,12 @@
/* VFS interface */
static int microcode_open(struct inode *, struct file *);
static int microcode_release(struct inode *, struct file *);
+static ssize_t microcode_read(struct file *, char *, size_t, loff_t *);
static ssize_t microcode_write(struct file *, const char *, size_t, loff_t *);
/* internal helpers to do the work */
-static void do_microcode_update(void);
+static int do_microcode_update(void);
static void do_update_one(void *);
/*
@@ -56,8 +59,10 @@
/* the actual array of microcode blocks, each 2048 bytes */
static struct microcode * microcode = NULL;
static unsigned int microcode_num = 0;
+static char *mc_applied = NULL; /* holds an array of applied microcode blocks */
static struct file_operations microcode_fops = {
+ read: microcode_read,
write: microcode_write,
open: microcode_open,
release: microcode_release,
@@ -71,21 +76,26 @@
static int __init microcode_init(void)
{
- /* write-only /proc/driver/microcode file, one day may become read-write.. */
- proc_microcode = create_proc_entry("microcode", S_IWUSR, proc_root_driver);
+ proc_microcode = create_proc_entry("microcode", S_IWUSR|S_IRUSR, proc_root_driver);
if (!proc_microcode) {
- printk(KERN_ERR "microcode: can't create /proc/driver/microcode entry\n");
+ printk(KERN_ERR "microcode: can't create /proc/driver/microcode\n");
return -ENOMEM;
}
proc_microcode->ops = µcode_inops;
- printk(KERN_ERR "P6 Microcode Update Driver v%s registered\n", MICROCODE_VERSION);
+ mc_applied = kmalloc(smp_num_cpus * sizeof(struct microcode), GFP_KERNEL);
+ if (!mc_applied) {
+ printk(KERN_ERR "microcode: can't allocate memory to hold applied microcode\n");
+ return -ENOMEM;
+ }
+ printk(KERN_INFO "P6 Microcode Update Driver v%s registered\n", MICROCODE_VERSION);
return 0;
}
static void __exit microcode_exit(void)
{
remove_proc_entry("microcode", proc_root_driver);
- printk(KERN_ERR "P6 Microcode Update Driver v%s unregistered\n", MICROCODE_VERSION);
+ kfree(mc_applied);
+ printk(KERN_INFO "P6 Microcode Update Driver v%s unregistered\n", MICROCODE_VERSION);
}
module_init(microcode_init);
@@ -117,22 +127,27 @@
}
-static void do_microcode_update(void)
+static int do_microcode_update(void)
{
- if (smp_call_function(do_update_one, NULL, 1, 0) != 0)
+ int err;
+
+ if (smp_call_function(do_update_one, &err, 1, 1) != 0)
panic("do_microcode_update(): timed out waiting for other CPUs\n");
- do_update_one(NULL);
+ do_update_one(&err);
+
+ return err;
}
-static void do_update_one(void *unused)
+static void do_update_one(void *arg)
{
+ int *err = (int *)arg;
struct cpuinfo_x86 * c;
unsigned int pf = 0, val[2], rev, sig;
int i, id;
id = smp_processor_id();
c = cpu_data + id;
-
+ *err = 1; /* be pessimistic */
if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6)
return;
@@ -156,9 +171,11 @@
" %d (current=%d)\n", id, microcode[i].rev, rev);
} else {
int sum = 0;
- struct microcode *m = µcode[i];
- unsigned int *sump = (unsigned int *)(m+1);
+ struct microcode *m, *mcslot;
+ unsigned int *sump;
+ m = µcode[i];
+ sump = (unsigned int *)(m+1);
while (--sump >= (unsigned int *)m)
sum += *sump;
if (sum != 0) {
@@ -169,23 +186,39 @@
wrmsr(0x79, (unsigned int)(m->bits), 0);
__asm__ __volatile__ ("cpuid");
rdmsr(0x8B, val[0], val[1]);
- printk(KERN_ERR "microcode: CPU%d microcode updated "
- "from revision %d to %d\n", id, rev, val[1]);
+ *err = 0;
+ mcslot = (struct microcode *)mc_applied + id;
+ memcpy(mcslot, m, sizeof(struct microcode));
+ printk(KERN_ERR "microcode: CPU%d updated from revision "
+ "%d to %d, date=%08x\n", id, rev, val[1], m->date);
}
break;
}
}
+static ssize_t microcode_read(struct file *file, char *buf, size_t len, loff_t *ppos)
+{
+ size_t fsize = smp_num_cpus * sizeof(struct microcode);
+
+ if (!proc_microcode->size || *ppos >= fsize)
+ return 0; /* EOF */
+ if (*ppos + len > fsize)
+ len = fsize - *ppos;
+ if (copy_to_user(buf, mc_applied + *ppos, len))
+ return -EFAULT;
+ *ppos += len;
+ return len;
+}
+
static ssize_t microcode_write(struct file *file, const char *buf, size_t len, loff_t *ppos)
{
+ int err;
+
if (len % sizeof(struct microcode) != 0) {
printk(KERN_ERR "microcode: can only write in N*%d bytes units\n",
sizeof(struct microcode));
return -EINVAL;
- return -EINVAL;
}
- if (!capable(CAP_SYS_RAWIO))
- return -EPERM;
lock_kernel();
microcode_num = len/sizeof(struct microcode);
microcode = vmalloc(len);
@@ -198,7 +231,11 @@
unlock_kernel();
return -EFAULT;
}
- do_microcode_update();
+ err = do_microcode_update();
+ if (err)
+ len = (size_t)err;
+ else
+ proc_microcode->size = smp_num_cpus * sizeof(struct microcode);
vfree(microcode);
unlock_kernel();
return len;
-
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This archive was generated by hypermail 2b29 : Wed Feb 23 2000 - 21:00:21 EST