Patch "x86/microcode: Replace deprecated CPU-hotplug functions." has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    x86/microcode: Replace deprecated CPU-hotplug functions.

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-microcode-replace-deprecated-cpu-hotplug-functio.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit dd90ba0dd2c2c01c6b00dc415b9c5987f95b330e
Author: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Date:   Tue Aug 3 16:15:51 2021 +0200

    x86/microcode: Replace deprecated CPU-hotplug functions.
    
    [ Upstream commit 2089f34f8c5b91f7235023ec72e71e3247261ecc ]
    
    The functions get_online_cpus() and put_online_cpus() have been
    deprecated during the CPU hotplug rework. They map directly to
    cpus_read_lock() and cpus_read_unlock().
    
    Replace deprecated CPU-hotplug functions with the official version.
    The behavior remains unchanged.
    
    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
    Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20210803141621.780504-9-bigeasy@xxxxxxxxxxxxx
    Stable-dep-of: c0dd9245aa9e ("x86/microcode: Check CPU capabilities after late microcode update correctly")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 0b1732b98e719..38a58819c1b9b 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -55,7 +55,7 @@ LIST_HEAD(microcode_cache);
  * All non cpu-hotplug-callback call sites use:
  *
  * - microcode_mutex to synchronize with each other;
- * - get/put_online_cpus() to synchronize with
+ * - cpus_read_lock/unlock() to synchronize with
  *   the cpu-hotplug-callback call sites.
  *
  * We guarantee that only a single cpu is being
@@ -431,7 +431,7 @@ static ssize_t microcode_write(struct file *file, const char __user *buf,
 		return ret;
 	}
 
-	get_online_cpus();
+	cpus_read_lock();
 	mutex_lock(&microcode_mutex);
 
 	if (do_microcode_update(buf, len) == 0)
@@ -441,7 +441,7 @@ static ssize_t microcode_write(struct file *file, const char __user *buf,
 		perf_check_microcode();
 
 	mutex_unlock(&microcode_mutex);
-	put_online_cpus();
+	cpus_read_unlock();
 
 	return ret;
 }
@@ -629,7 +629,7 @@ static ssize_t reload_store(struct device *dev,
 	if (val != 1)
 		return size;
 
-	get_online_cpus();
+	cpus_read_lock();
 
 	ret = check_online_cpus();
 	if (ret)
@@ -644,7 +644,7 @@ static ssize_t reload_store(struct device *dev,
 	mutex_unlock(&microcode_mutex);
 
 put:
-	put_online_cpus();
+	cpus_read_unlock();
 
 	if (ret == 0)
 		ret = size;
@@ -853,14 +853,14 @@ int __init microcode_init(void)
 	if (IS_ERR(microcode_pdev))
 		return PTR_ERR(microcode_pdev);
 
-	get_online_cpus();
+	cpus_read_lock();
 	mutex_lock(&microcode_mutex);
 
 	error = subsys_interface_register(&mc_cpu_interface);
 	if (!error)
 		perf_check_microcode();
 	mutex_unlock(&microcode_mutex);
-	put_online_cpus();
+	cpus_read_unlock();
 
 	if (error)
 		goto out_pdev;
@@ -892,13 +892,13 @@ int __init microcode_init(void)
 			   &cpu_root_microcode_group);
 
  out_driver:
-	get_online_cpus();
+	cpus_read_lock();
 	mutex_lock(&microcode_mutex);
 
 	subsys_interface_unregister(&mc_cpu_interface);
 
 	mutex_unlock(&microcode_mutex);
-	put_online_cpus();
+	cpus_read_unlock();
 
  out_pdev:
 	platform_device_unregister(microcode_pdev);