queue-5.10/cpufreq-dt-always-allocate-zeroed-cpumask.patch

   1 From 82988c5aea66c118f5dbd66de066c6d2f81dbeaf Mon Sep 17 00:00:00 2001
   2 From: Sasha Levin <sashal@kernel.org>
   3 Date: Thu, 14 Mar 2024 13:54:57 +0100
   4 Subject: cpufreq: dt: always allocate zeroed cpumask
   5
   6 From: Marek Szyprowski <m.szyprowski@samsung.com>
   7
   8 [ Upstream commit d2399501c2c081eac703ca9597ceb83c7875a537 ]
   9
  10 Commit 0499a78369ad ("ARM64: Dynamically allocate cpumasks and increase
  11 supported CPUs to 512") changed the handling of cpumasks on ARM 64bit,
  12 what resulted in the strange issues and warnings during cpufreq-dt
  13 initialization on some big.LITTLE platforms.
  14
  15 This was caused by mixing OPPs between big and LITTLE cores, because
  16 OPP-sharing information between big and LITTLE cores is computed on
  17 cpumask, which in turn was not zeroed on allocation. Fix this by
  18 switching to zalloc_cpumask_var() call.
  19
  20 Fixes: dc279ac6e5b4 ("cpufreq: dt: Refactor initialization to handle probe deferral properly")
  21 CC: stable@vger.kernel.org # v5.10+
  22 Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
  23 Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
  24 Reviewed-by: Dhruva Gole <d-gole@ti.com>
  25 Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
  26 Signed-off-by: Sasha Levin <sashal@kernel.org>
  27 ---
  28  drivers/cpufreq/cpufreq-dt.c | 2 +-
  29  1 file changed, 1 insertion(+), 1 deletion(-)
  30
  31 diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
  32 index e363ae04aac62..44cc596ca0a5e 100644
  33 --- a/drivers/cpufreq/cpufreq-dt.c
  34 +++ b/drivers/cpufreq/cpufreq-dt.c
  35 @@ -251,7 +251,7 @@ static int dt_cpufreq_early_init(struct device *dev, int cpu)
  36         if (!priv)
  37                 return -ENOMEM;
  38
  39 -       if (!alloc_cpumask_var(&priv->cpus, GFP_KERNEL))
  40 +       if (!zalloc_cpumask_var(&priv->cpus, GFP_KERNEL))
  41                 return -ENOMEM;
  42
  43         priv->cpu_dev = cpu_dev;
  44 --
  45 2.43.0
  46