Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

x86, microcode, AMD: Add a small, per-family patches cache

Browse source 
This is a trivial cache which collects all ucode patches for the current
family of CPUs on the system. If a newer patch appears due to the
container file being updated in userspace, we replace our cached version
with the new one.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-12-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Borislav Petkov 2012-08-01 15:38:18 +02:00 committed by H. Peter Anvin
parent c96d2c0905
commit a3eb3b4da1
1 changed files with 66 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

67
arch/x86/kernel/microcode_amd.c
View file

@ -78,12 +78,22 @@ static struct equiv_cpu_entry *equiv_cpu_table;
/* page-sized ucode patch buffer */
void *patch;
struct ucode_patch {
struct list_head plist;
void *data;
u32 patch_id;
u16 equiv_cpu;
};
static LIST_HEAD(pcache);
static u16 find_equiv_id(unsigned int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
int i = 0;
BUG_ON(equiv_cpu_table == NULL);
if (!equiv_cpu_table)
return 0;
while (equiv_cpu_table[i].installed_cpu != 0) {
if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)
@ -108,6 +118,61 @@ static u32 find_cpu_family_by_equiv_cpu(u16 equiv_cpu)
return 0;
}
/*
* a small, trivial cache of per-family ucode patches
*/
static struct ucode_patch *cache_find_patch(u16 equiv_cpu)
{
struct ucode_patch *p;
list_for_each_entry(p, &pcache, plist)
if (p->equiv_cpu == equiv_cpu)
return p;
return NULL;
}
static void update_cache(struct ucode_patch *new_patch)
{
struct ucode_patch *p;
list_for_each_entry(p, &pcache, plist) {
if (p->equiv_cpu == new_patch->equiv_cpu) {
if (p->patch_id >= new_patch->patch_id)
/* we already have the latest patch */
return;
list_replace(&p->plist, &new_patch->plist);
kfree(p->data);
kfree(p);
return;
}
}
/* no patch found, add it */
list_add_tail(&new_patch->plist, &pcache);
}
static void free_cache(void)
{
struct ucode_patch *p;
list_for_each_entry_reverse(p, &pcache, plist) {
__list_del(p->plist.prev, p->plist.next);
kfree(p->data);
kfree(p);
}
}
static struct ucode_patch *find_patch(unsigned int cpu)
{
u16 equiv_id;
equiv_id = find_equiv_id(cpu);
if (!equiv_id)
return NULL;
return cache_find_patch(equiv_id);
}
static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
{
struct cpuinfo_x86 *c = &cpu_data(cpu);