[SRU][J][PULL] hwmon: (coretemp) Fix core count limitation

[Thibault Ferrante]

BugLink: https://bugs.launchpad.net/bugs/2058668

[Impact]

In linux 6.8 the coretemp driver supports at most 128 cores per package.
Cores higher than 128 will lose their core temperature information.

There is an upstream patch set that allows to support more than 128
cores per package, it's applied to linux-next, then to Noble.

We should apply the patch set to the Jammy 5.15 kernel, so that we can
properly support systems with a large amount of cores per package.

[Test case]

Read temperature info from /sys/class/hwmon on a system with > 128 cores
per package (that means we don't have a proper test case to verify the
fix at the moment).

[Fix]

A series of patch is part of this improvement:

1a793caf6f69 hwmon: (coretemp) Use dynamic allocated memory for core temp_data
18b24a5f9ca3 hwmon: (coretemp) Remove redundant temp_data->is_pkg_data
326241f71f3d hwmon: (coretemp) Split package temp_data and core temp_data
b0b01414a261 hwmon: (coretemp) Abstract core_temp helpers
87eb801925a0 hwmon: (coretemp) Remove redundant pdata->cpu_map[]
18d8f5583388 hwmon: (coretemp) Replace sensor_device_attribute with device_attribute
25f8e01baa05 hwmon: (coretemp) Remove unnecessary dependency of array index
c8c2074020a8 hwmon: (coretemp) Introduce enum for attr index

And some patch are required to make the backporting clean:

34cf8c657cf03 hwmon: (coretemp) Enlarge per package core count limit
fdaf0c8629d45 hwmon: (coretemp) Fix bogus core_id to attr name mapping
4e440abc89458 hwmon: (coretemp) Fix out-of-bounds memory access
a2930f6dc90f0 hwmon: (coretemp) Delete an obsolete comment
6c2b659913ad9 hwmon: (coretemp) Delete tjmax debug message
0f8b916bc5b5d hwmon: (coretemp) avoid RDMSR interrupts to isolated CPUs
fae30e3c203e0 hwmon: (coretemp) Add support for dynamic ttarget
c0c67f8761cec hwmon: (coretemp) Add support for dynamic tjmax
2bc0e6d07ee50 hwmon: (coretemp) rearrange tjmax handing code
5c0e64dde80ff hwmon: (coretemp) Remove obsolete temp_data->valid

Only 5c0e64dde80ff has to be modified as it's deleting a variable which changed type
because of a refactoring.

There is a number of commits, but they are only changing one file.

[Regression potential]

We may experience hwmon-related regressions, either systems reading
incorrect temperature information or even bugs/crashes when accessing
data from /sys/class/hwmon.

The following changes since commit 54bc2c0c9882a:

  hwmon: (coretemp) Remove obsolete temp_data->valid

are available in the Git repository at:

  git://git.launchpad.net/~thibf/+git/jammy-linux bug2058668

for you to fetch changes up to 1bf7903b38225:

  hwmon: (coretemp) Use dynamic allocated memory for core temp_data

----------------------------------------------------------------
Marcelo Tosatti (1):
  hwmon: (coretemp) avoid RDMSR interrupts to isolated CPUs

Thibault Ferrante (1):
  hwmon: (coretemp) Remove obsolete temp_data->valid

Zhang Rui (15):
  hwmon: (coretemp) rearrange tjmax handing code
  hwmon: (coretemp) Add support for dynamic tjmax
  hwmon: (coretemp) Add support for dynamic ttarget
  hwmon: (coretemp) Delete tjmax debug message
  hwmon: (coretemp) Fix out-of-bounds memory access
  hwmon: (coretemp) Fix bogus core_id to attr name mapping
  hwmon: (coretemp) Enlarge per package core count limit
  hwmon: (coretemp) Introduce enum for attr index
  hwmon: (coretemp) Remove unnecessary dependency of array index
  hwmon: (coretemp) Replace sensor_device_attribute with
    device_attribute
  hwmon: (coretemp) Remove redundant pdata->cpu_map[]
  hwmon: (coretemp) Abstract core_temp helpers
  hwmon: (coretemp) Split package temp_data and core temp_data
  hwmon: (coretemp) Remove redundant temp_data->is_pkg_data
  hwmon: (coretemp) Use dynamic allocated memory for core temp_data

 drivers/hwmon/coretemp.c | 434 ++++++++++++++++++++++-----------------
 1 file changed, 246 insertions(+), 188 deletions(-)

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2.43.0