Commit 2c34f19f authored by Aichun Shi's avatar Aichun Shi
Browse files

Revert "x86/microcode: Rip out the subsys interface gunk" 

Intel inclusion
category: feature
feature: Backport Intel In Field Scan(IFS) multi-blob images support
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I6L337


CVE: N/A
Reference: N/A

Intel-SIG: Revert commit 6499df46 ("x86/microcode: Rip out the
subsys interface gunk")

-------------------------------------

This reverts commit 6499df46.

This revert is to recover old microcode interface /dev/cpu/microcode.

Signed-off-by: default avatarAichun Shi <aichun.shi@intel.com>
parent 2bbd2904

arch/x86/kernel/cpu/microcode/core.c

+58 −20
Original line number Diff line number Diff line
@@ -618,8 +618,8 @@ static enum ucode_state microcode_resume_cpu(int cpu) 


static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)

{

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;

	enum ucode_state ustate;

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;



	if (uci->valid)

		return UCODE_OK;
@@ -653,6 +653,44 @@ static enum ucode_state microcode_update_cpu(int cpu) 
	return microcode_init_cpu(cpu, false);

}



static int mc_device_add(struct device *dev, struct subsys_interface *sif)

{

	int err, cpu = dev->id;



	if (!cpu_online(cpu))

		return 0;



	pr_debug("CPU%d added\n", cpu);



	err = sysfs_create_group(&dev->kobj, &mc_attr_group);

	if (err)

		return err;



	if (microcode_init_cpu(cpu, true) == UCODE_ERROR)

		return -EINVAL;



	return err;

}



static void mc_device_remove(struct device *dev, struct subsys_interface *sif)

{

	int cpu = dev->id;



	if (!cpu_online(cpu))

		return;



	pr_debug("CPU%d removed\n", cpu);

	microcode_fini_cpu(cpu);

	sysfs_remove_group(&dev->kobj, &mc_attr_group);

}



static struct subsys_interface mc_cpu_interface = {

	.name			= "microcode",

	.subsys			= &cpu_subsys,

	.add_dev		= mc_device_add,

	.remove_dev		= mc_device_remove,

};



/**

 * microcode_bsp_resume - Update boot CPU microcode during resume.

 */
@@ -692,9 +730,6 @@ static int mc_cpu_down_prep(unsigned int cpu) 
	struct device *dev;



	dev = get_cpu_device(cpu);



	microcode_fini_cpu(cpu);



	/* Suspend is in progress, only remove the interface */

	sysfs_remove_group(&dev->kobj, &mc_attr_group);

	pr_debug("CPU%d removed\n", cpu);
@@ -702,18 +737,6 @@ static int mc_cpu_down_prep(unsigned int cpu) 
	return 0;

}



static void setup_online_cpu(struct work_struct *work)

{

	int cpu = smp_processor_id();

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;



	memset(uci, 0, sizeof(*uci));



	microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig);



	mc_cpu_online(cpu);

}



static struct attribute *cpu_root_microcode_attrs[] = {

#ifdef CONFIG_MICROCODE_LATE_LOADING

	&dev_attr_reload.attr,
@@ -749,17 +772,23 @@ int __init microcode_init(void) 
	if (IS_ERR(microcode_pdev))

		return PTR_ERR(microcode_pdev);



	get_online_cpus();

	mutex_lock(&microcode_mutex);

	error = subsys_interface_register(&mc_cpu_interface);

	mutex_unlock(&microcode_mutex);

	put_online_cpus();



	if (error)

		goto out_pdev;



	error = sysfs_create_group(&cpu_subsys.dev_root->kobj,

				   &cpu_root_microcode_group);



	if (error) {

		pr_err("Error creating microcode group!\n");

		goto out_pdev;

		goto out_driver;

	}



	/* Do per-CPU setup */

	schedule_on_each_cpu(setup_online_cpu);



	register_syscore_ops(&mc_syscore_ops);

	cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",

				  mc_cpu_starting, NULL);
@@ -770,6 +799,15 @@ int __init microcode_init(void) 


	return 0;



 out_driver:

	get_online_cpus();

	mutex_lock(&microcode_mutex);



	subsys_interface_unregister(&mc_cpu_interface);



	mutex_unlock(&microcode_mutex);

	put_online_cpus();



 out_pdev:

	platform_device_unregister(microcode_pdev);

	return error;