Linux kernel -stable discussions
 help / color / mirror / Atom feed
From: <gregkh@linuxfoundation.org>
To: rafael.j.wysocki@intel.com,henrytseng@qnap.com,stable@vger.kernel.org
Cc: <stable@vger.kernel.org>
Subject: FAILED: patch "[PATCH] cpufreq: intel_pstate: Use correct scaling factor on Raptor" failed to apply to 6.18-stable tree
Date: Thu, 28 May 2026 13:47:46 +0200	[thread overview]
Message-ID: <2026052846-jasmine-recess-d8cc@gregkh> (raw)


The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 0e7c710478b3089cdfe8669347f77b163e836c4f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026052846-jasmine-recess-d8cc@gregkh' --subject-prefix 'PATCH 6.18.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 0e7c710478b3089cdfe8669347f77b163e836c4f Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Tue, 12 May 2026 21:20:30 +0200
Subject: [PATCH] cpufreq: intel_pstate: Use correct scaling factor on Raptor
 Lake-E

Raptor Lake-E has the same processor ID as Raptor Lake-S, so there is
an entry in intel_hybrid_scaling_factor[] for it.  It does not contain
E-cores though and hybrid_get_cpu_type() returns 0 for its P-cores, so
they get the default "core" scaling factor.  However, the original
Raptor Lake scaling factor for P-cores still needs to be used for
mapping the HWP performance levels of the P-cores in Raptor Lake-E to
frequency, as though they were part of a real hybrid system.

To address this, update hwp_get_cpu_scaling() to return
hybrid_scaling_factor, which is the P-core scaling factor
retrieved from intel_hybrid_scaling_factor[], for all CPUs
that are not enumerated as E-cores.

Fixes: 9b18d536b124 ("cpufreq: intel_pstate: Use CPPC to get scaling factors")
Link: https://lore.kernel.org/all/20260511235328.2018458-1-srinivas.pandruvada@linux.intel.com/
Reported-by: Henry Tseng <henrytseng@qnap.com>
Closes: https://lore.kernel.org/linux-pm/20260508063032.3248602-1-henrytseng@qnap.com/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: All applicable <stable@vger.kernel.org>
Link: https://patch.msgid.link/4523296.ejJDZkT8p0@rafael.j.wysocki

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 1292da53e5fc..978e2b604ac8 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2279,7 +2279,7 @@ static int hwp_get_cpu_scaling(int cpu)
 		 * Return the hybrid scaling factor for P-cores and use the
 		 * default core scaling for E-cores.
 		 */
-		if (hybrid_get_cpu_type(cpu) == INTEL_CPU_TYPE_CORE)
+		if (hybrid_get_cpu_type(cpu) != INTEL_CPU_TYPE_ATOM)
 			return hybrid_scaling_factor;
 
 		return core_get_scaling();


                 reply	other threads:[~2026-05-28 11:48 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=2026052846-jasmine-recess-d8cc@gregkh \
    --to=gregkh@linuxfoundation.org \
    --cc=henrytseng@qnap.com \
    --cc=rafael.j.wysocki@intel.com \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox