This is a note to let you know that I've just added the patch titled
cpufreq: amd-pstate: fix kernel hang issue while amd-pstate unregistering
to the 6.1-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:
cpufreq-amd-pstate-fix-kernel-hang-issue-while-amd-pstate-unregistering.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4f3085f87b51a551a0647f218d4f324796ecb703 Mon Sep 17 00:00:00 2001
From: Perry Yuan <perry.yuan@xxxxxxx>
Date: Tue, 10 Jan 2023 23:10:29 +0800
Subject: cpufreq: amd-pstate: fix kernel hang issue while amd-pstate unregistering
From: Perry Yuan <perry.yuan@xxxxxxx>
commit 4f3085f87b51a551a0647f218d4f324796ecb703 upstream.
In the amd_pstate_adjust_perf(), there is one cpufreq_cpu_get() call to
increase increments the kobject reference count of policy and make it as
busy. Therefore, a corresponding call to cpufreq_cpu_put() is needed to
decrement the kobject reference count back, it will resolve the kernel
hang issue when unregistering the amd-pstate driver and register the
`amd_pstate_epp` driver instance.
Fixes: 1d215f0319 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State")
Acked-by: Huang Rui <ray.huang@xxxxxxx>
Reviewed-by: Mario Limonciello <mario.limonciello@xxxxxxx>
Tested-by: Wyes Karny <wyes.karny@xxxxxxx>
Signed-off-by: Perry Yuan <perry.yuan@xxxxxxx>
Cc: 5.17+ <stable@xxxxxxxxxxxxxxx> # 5.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/cpufreq/amd-pstate.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -307,6 +307,7 @@ static void amd_pstate_adjust_perf(unsig
max_perf = min_perf;
amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true);
+ cpufreq_cpu_put(policy);
}
static int amd_get_min_freq(struct amd_cpudata *cpudata)
Patches currently in stable-queue which might be from perry.yuan@xxxxxxx are
queue-6.1/cpufreq-amd-pstate-fix-kernel-hang-issue-while-amd-pstate-unregistering.patch
