[PATCH v3 04/16] platform/x86/intel/ifs: Remove memory allocation from load path

Jithu Joseph
2022-11-17T04:01:38Z

IFS requires tests to be authenticated once for each CPU socket
on a system.

scan_chunks_sanity_check() was dynamically allocating memory
to store the state of whether tests have been authenticated on
each socket for every load operation.

Move the memory allocation to init path.

Reviewed-by: Tony Luck <tony.luck@intel.com>
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
---
drivers/platform/x86/intel/ifs/ifs.h | 2 ++
drivers/platform/x86/intel/ifs/core.c | 13 +++++++++++--
drivers/platform/x86/intel/ifs/load.c | 14 ++++----------
3 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/platform/x86/intel/ifs/ifs.h b/drivers/platform/x86/intel/ifs/ifs.h
index 3ff1d9aaeaa9..3a051890d9e7 100644
--- a/drivers/platform/x86/intel/ifs/ifs.h
+++ b/drivers/platform/x86/intel/ifs/ifs.h
@@ -229,4 +229,6 @@ void ifs_load_firmware(struct device *dev);
int do_core_test(int cpu, struct device *dev);
const struct attribute_group **ifs_get_groups(void);

+extern bool *ifs_pkg_auth;
+
#endif
diff --git a/drivers/platform/x86/intel/ifs/core.c b/drivers/platform/x86/intel/ifs/core.c
index 5fb7f655c291..4b39f2359180 100644
--- a/drivers/platform/x86/intel/ifs/core.c
+++ b/drivers/platform/x86/intel/ifs/core.c
@@ -4,6 +4,7 @@
#include <linux/module.h>
#include <linux/kdev_t.h>
#include <linux/semaphore.h>
+#include <linux/slab.h>

#include <asm/cpu_device_id.h>

@@ -30,6 +31,8 @@ static struct ifs_device ifs_device = {
},
};

+bool *ifs_pkg_auth;
+
static int __init ifs_init(void)
{
const struct x86_cpu_id *m;
@@ -51,8 +54,13 @@ static int __init ifs_init(void)
ifs_device.misc.groups = ifs_get_groups();

if ((msrval & BIT(ifs_device.data.integrity_cap_bit)) &&
- !misc_register(&ifs_device.misc))
- return 0;
+ !misc_register(&ifs_device.misc)) {
+ ifs_pkg_auth = kmalloc_array(topology_max_packages(), sizeof(bool), GFP_KERNEL);
+ if (!ifs_pkg_auth)
+ return -ENOMEM;
+ else
+ return 0;
+ }

return -ENODEV;
}
@@ -60,6 +68,7 @@ static int __init ifs_init(void)
static void __exit ifs_exit(void)
{
misc_deregister(&ifs_device.misc);
+ kfree(ifs_pkg_auth);
}

module_init(ifs_init);
diff --git a/drivers/platform/x86/intel/ifs/load.c b/drivers/platform/x86/intel/ifs/load.c
index 89ce265887ea..c914e4d359db 100644
--- a/drivers/platform/x86/intel/ifs/load.c
+++ b/drivers/platform/x86/intel/ifs/load.c
@@ -3,7 +3,6 @@

#include <linux/firmware.h>
#include <asm/cpu.h>
-#include <linux/slab.h>
#include <asm/microcode_intel.h>

#include "ifs.h"
@@ -118,16 +117,12 @@ static void copy_hashes_authenticate_chunks(struct work_struct *work)
*/
static int scan_chunks_sanity_check(struct device *dev)
{
- int metadata_size, curr_pkg, cpu, ret = -ENOMEM;
+ int metadata_size, curr_pkg, cpu, ret;
struct ifs_data *ifsd = ifs_get_data(dev);
- bool *package_authenticated;
struct ifs_work local_work;
char *test_ptr;

- package_authenticated = kcalloc(topology_max_packages(), sizeof(bool), GFP_KERNEL);
- if (!package_authenticated)
- return ret;
-
+ memset(ifs_pkg_auth, 0, (topology_max_packages() * sizeof(bool)));
metadata_size = ifs_header_ptr->metadata_size;

/* Spec says that if the Meta Data Size = 0 then it should be treated as 2000 */
@@ -150,7 +145,7 @@ static int scan_chunks_sanity_check(struct device *dev)
cpus_read_lock();
for_each_online_cpu(cpu) {
curr_pkg = topology_physical_package_id(cpu);
- if (package_authenticated[curr_pkg])
+ if (ifs_pkg_auth[curr_pkg])
continue;
reinit_completion(&ifs_done);
local_work.dev = dev;
@@ -161,12 +156,11 @@ static int scan_chunks_sanity_check(struct device *dev)
ret = -EIO;
goto out;
}
- package_authenticated[curr_pkg] = 1;
+ ifs_pkg_auth[curr_pkg] = 1;
}
ret = 0;
out:
cpus_read_unlock();
- kfree(package_authenticated);

return ret;
}
--
2.25.1