Merge tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kern…

…el/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT.

 - Allow per-process DEXCR (Dynamic Execution Control Register) settings
   via prctl, notably NPHIE which controls hashst/hashchk for ROP
   protection.

 - Install powerpc selftests in sub-directories. Note this changes the
   way run_kselftest.sh needs to be invoked for powerpc selftests.

 - Change fadump (Firmware Assisted Dump) to better handle memory
   add/remove.

 - Add support for passing additional parameters to the fadump kernel.

 - Add support for updating the kdump image on CPU/memory add/remove
   events.

 - Other small features, cleanups and fixes.

Thanks to Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd
Bergmann, Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe
Jaillet, Christophe Leroy, Colin Ian King, Cédric Le Goater, Dr. David
Alan Gilbert, Erhard Furtner, Frank Li, GUO Zihua, Ganesh Goudar, Geoff
Levand, Ghanshyam Agrawal, Greg Kurz, Hari Bathini, Joel Stanley, Justin
Stitt, Kunwu Chan, Li Yang, Lidong Zhong, Madhavan Srinivasan, Mahesh
Salgaonkar, Masahiro Yamada, Matthias Schiffer, Naresh Kamboju, Nathan
Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Miehlbradt, Ran Wang,
Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta, Shrikanth
Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav
Jain, Xiaowei Bao, Yang Li, and Zhao Chenhui.

* tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (85 commits)
  powerpc/fadump: Fix section mismatch warning
  powerpc/85xx: fix compile error without CONFIG_CRASH_DUMP
  powerpc/fadump: update documentation about bootargs_append
  powerpc/fadump: pass additional parameters when fadump is active
  powerpc/fadump: setup additional parameters for dump capture kernel
  powerpc/pseries/fadump: add support for multiple boot memory regions
  selftests/powerpc/dexcr: Fix spelling mistake "predicition" -> "prediction"
  KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info()
  KVM: PPC: Fix documentation for ppc mmu caps
  KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver
  KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception
  powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#"
  powerpc/code-patching: Use dedicated memory routines for patching
  powerpc/code-patching: Test patch_instructions() during boot
  powerpc64/kasan: Pass virtual addresses to kasan_init_phys_region()
  powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX
  powerpc: Fix typos
  powerpc/eeh: Fix spelling of the word "auxillary" and update comment
  macintosh/ams: Fix unused variable warning
  powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large
  ...

Documentation/ABI/testing/sysfs-devices-system-cpu

@@ -423,7 +423,7 @@ What:		/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats
 		/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset
 Date:		March 2016
 Contact:	Linux kernel mailing list <[email protected]>
-		Linux for PowerPC mailing list <[email protected]>
+		Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	POWERNV CPUFreq driver's frequency throttle stats directory and
 		attributes
 
@@ -473,7 +473,7 @@ What:		/sys/devices/system/cpu/cpufreq/policyX/throttle_stats
 		/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/occ_reset
 Date:		March 2016
 Contact:	Linux kernel mailing list <[email protected]>
-		Linux for PowerPC mailing list <[email protected]>
+		Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	POWERNV CPUFreq driver's frequency throttle stats directory and
 		attributes
 
@@ -608,7 +608,7 @@ Description:	Umwait control
 What:		/sys/devices/system/cpu/svm
 Date:		August 2019
 Contact:	Linux kernel mailing list <[email protected]>
-		Linux for PowerPC mailing list <[email protected]>
+		Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Secure Virtual Machine
 
 		If 1, it means the system is using the Protected Execution
@@ -617,7 +617,7 @@ Description:	Secure Virtual Machine
 
 What:		/sys/devices/system/cpu/cpuX/purr
 Date:		Apr 2005
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	PURR ticks for this CPU since the system boot.
 
 		The Processor Utilization Resources Register (PURR) is
@@ -628,7 +628,7 @@ Description:	PURR ticks for this CPU since the system boot.
 
 What: 		/sys/devices/system/cpu/cpuX/spurr
 Date:		Dec 2006
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	SPURR ticks for this CPU since the system boot.
 
 		The Scaled Processor Utilization Resources Register
@@ -640,15 +640,15 @@ Description:	SPURR ticks for this CPU since the system boot.
 
 What: 		/sys/devices/system/cpu/cpuX/idle_purr
 Date:		Apr 2020
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	PURR ticks for cpuX when it was idle.
 
 		This sysfs interface exposes the number of PURR ticks
 		for cpuX when it was idle.
 
 What: 		/sys/devices/system/cpu/cpuX/idle_spurr
 Date:		Apr 2020
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	SPURR ticks for cpuX when it was idle.
 
 		This sysfs interface exposes the number of SPURR ticks

Documentation/ABI/testing/sysfs-firmware-opal-powercap

@@ -1,6 +1,6 @@
 What:		/sys/firmware/opal/powercap
 Date:		August 2017
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Powercap directory for Powernv (P8, P9) servers
 
 		Each folder in this directory contains a
@@ -11,7 +11,7 @@ What:		/sys/firmware/opal/powercap/system-powercap
 		/sys/firmware/opal/powercap/system-powercap/powercap-max
 		/sys/firmware/opal/powercap/system-powercap/powercap-current
 Date:		August 2017
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	System powercap directory and attributes applicable for
 		Powernv (P8, P9) servers
 

Documentation/ABI/testing/sysfs-firmware-opal-psr

@@ -1,6 +1,6 @@
 What:		/sys/firmware/opal/psr
 Date:		August 2017
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Power-Shift-Ratio directory for Powernv P9 servers
 
 		Power-Shift-Ratio allows to provide hints the firmware
@@ -10,7 +10,7 @@ Description:	Power-Shift-Ratio directory for Powernv P9 servers
 
 What:		/sys/firmware/opal/psr/cpu_to_gpu_X
 Date:		August 2017
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	PSR sysfs attributes for Powernv P9 servers
 
 		Power-Shift-Ratio between CPU and GPU for a given chip

Documentation/ABI/testing/sysfs-firmware-opal-sensor-groups

@@ -1,6 +1,6 @@
 What:		/sys/firmware/opal/sensor_groups
 Date:		August 2017
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Sensor groups directory for POWER9 powernv servers
 
 		Each folder in this directory contains a sensor group
@@ -11,7 +11,7 @@ Description:	Sensor groups directory for POWER9 powernv servers
 
 What:		/sys/firmware/opal/sensor_groups/<sensor_group_name>/clear
 Date:		August 2017
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Sysfs file to clear the min-max of all the sensors
 		belonging to the group.
 

Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info

@@ -1,6 +1,6 @@
 What:		/sys/firmware/papr/energy_scale_info
 Date:		February 2022
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Directory hosting a set of platform attributes like
 		energy/frequency on Linux running as a PAPR guest.
 
@@ -10,20 +10,20 @@ Description:	Directory hosting a set of platform attributes like
 
 What:		/sys/firmware/papr/energy_scale_info/<id>
 Date:		February 2022
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Energy, frequency attributes directory for POWERVM servers
 
 What:		/sys/firmware/papr/energy_scale_info/<id>/desc
 Date:		February 2022
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	String description of the energy attribute of <id>
 
 What:		/sys/firmware/papr/energy_scale_info/<id>/value
 Date:		February 2022
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	Numeric value of the energy attribute of <id>
 
 What:		/sys/firmware/papr/energy_scale_info/<id>/value_desc
 Date:		February 2022
-Contact:	Linux for PowerPC mailing list <[email protected]>
+Contact:	Linux for PowerPC mailing list <linuxppc-dev@lists.ozlabs.org>
 Description:	String value of the energy attribute of <id>

Documentation/ABI/testing/sysfs-kernel-fadump

@@ -38,3 +38,21 @@ Contact:	[email protected]
 Description:	read only
 		Provide information about the amount of memory reserved by
 		FADump to save the crash dump in bytes.
+
+What:		/sys/kernel/fadump/hotplug_ready
+Date:		Apr 2024
+Contact:	[email protected]
+Description:	read only
+		Kdump udev rule re-registers fadump on memory add/remove events,
+		primarily to update the elfcorehdr. This sysfs indicates the
+		kdump udev rule that fadump re-registration is not required on
+		memory add/remove events because elfcorehdr is now prepared in
+		the second/fadump kernel.
+User:		kexec-tools
+
+What:		/sys/kernel/fadump/bootargs_append
+Date:		May 2024
+Contact:	[email protected]
+Description:	read/write
+		This is a special sysfs file available to setup additional
+		parameters to be passed to capture kernel.

Documentation/arch/powerpc/dexcr.rst

@@ -36,8 +36,145 @@ state for a process.
 Configuration
 =============
 
-The DEXCR is currently unconfigurable. All threads are run with the
-NPHIE aspect enabled.
+prctl
+-----
+
+A process can control its own userspace DEXCR value using the
+``PR_PPC_GET_DEXCR`` and ``PR_PPC_SET_DEXCR`` pair of
+:manpage:`prctl(2)` commands. These calls have the form::
+
+    prctl(PR_PPC_GET_DEXCR, unsigned long which, 0, 0, 0);
+    prctl(PR_PPC_SET_DEXCR, unsigned long which, unsigned long ctrl, 0, 0);
+
+The possible 'which' and 'ctrl' values are as follows. Note there is no relation
+between the 'which' value and the DEXCR aspect's index.
+
+.. flat-table::
+   :header-rows: 1
+   :widths: 2 7 1
+
+   * - ``prctl()`` which
+     - Aspect name
+     - Aspect index
+
+   * - ``PR_PPC_DEXCR_SBHE``
+     - Speculative Branch Hint Enable (SBHE)
+     - 0
+
+   * - ``PR_PPC_DEXCR_IBRTPD``
+     - Indirect Branch Recurrent Target Prediction Disable (IBRTPD)
+     - 3
+
+   * - ``PR_PPC_DEXCR_SRAPD``
+     - Subroutine Return Address Prediction Disable (SRAPD)
+     - 4
+
+   * - ``PR_PPC_DEXCR_NPHIE``
+     - Non-Privileged Hash Instruction Enable (NPHIE)
+     - 5
+
+.. flat-table::
+   :header-rows: 1
+   :widths: 2 8
+
+   * - ``prctl()`` ctrl
+     - Meaning
+
+   * - ``PR_PPC_DEXCR_CTRL_EDITABLE``
+     - This aspect can be configured with PR_PPC_SET_DEXCR (get only)
+
+   * - ``PR_PPC_DEXCR_CTRL_SET``
+     - This aspect is set / set this aspect
+
+   * - ``PR_PPC_DEXCR_CTRL_CLEAR``
+     - This aspect is clear / clear this aspect
+
+   * - ``PR_PPC_DEXCR_CTRL_SET_ONEXEC``
+     - This aspect will be set after exec / set this aspect after exec
+
+   * - ``PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC``
+     - This aspect will be clear after exec / clear this aspect after exec
+
+Note that
+
+* which is a plain value, not a bitmask. Aspects must be worked with individually.
+
+* ctrl is a bitmask. ``PR_PPC_GET_DEXCR`` returns both the current and onexec
+  configuration. For example, ``PR_PPC_GET_DEXCR`` may return
+  ``PR_PPC_DEXCR_CTRL_EDITABLE | PR_PPC_DEXCR_CTRL_SET |
+  PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC``. This would indicate the aspect is currently
+  set, it will be cleared when you run exec, and you can change this with the
+  ``PR_PPC_SET_DEXCR`` prctl.
+
+* The set/clear terminology refers to setting/clearing the bit in the DEXCR.
+  For example::
+
+      prctl(PR_PPC_SET_DEXCR, PR_PPC_DEXCR_IBRTPD, PR_PPC_DEXCR_CTRL_SET, 0, 0);
+
+  will set the IBRTPD aspect bit in the DEXCR, causing indirect branch prediction
+  to be disabled.
+
+* The status returned by ``PR_PPC_GET_DEXCR`` represents what value the process
+  would like applied. It does not include any alternative overrides, such as if
+  the hypervisor is enforcing the aspect be set. To see the true DEXCR state
+  software should read the appropriate SPRs directly.
+
+* The aspect state when starting a process is copied from the parent's state on
+  :manpage:`fork(2)`. The state is reset to a fixed value on
+  :manpage:`execve(2)`. The PR_PPC_SET_DEXCR prctl() can control both of these
+  values.
+
+* The ``*_ONEXEC`` controls do not change the current process's DEXCR.
+
+Use ``PR_PPC_SET_DEXCR`` with one of ``PR_PPC_DEXCR_CTRL_SET`` or
+``PR_PPC_DEXCR_CTRL_CLEAR`` to edit a given aspect.
+
+Common error codes for both getting and setting the DEXCR are as follows:
+
+.. flat-table::
+   :header-rows: 1
+   :widths: 2 8
+
+   * - Error
+     - Meaning
+
+   * - ``EINVAL``
+     - The DEXCR is not supported by the kernel.
+
+   * - ``ENODEV``
+     - The aspect is not recognised by the kernel or not supported by the
+       hardware.
+
+``PR_PPC_SET_DEXCR`` may also report the following error codes:
+
+.. flat-table::
+   :header-rows: 1
+   :widths: 2 8
+
+   * - Error
+     - Meaning
+
+   * - ``EINVAL``
+     - The ctrl value contains unrecognised flags.
+
+   * - ``EINVAL``
+     - The ctrl value contains mutually conflicting flags (e.g.,
+       ``PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR``)
+
+   * - ``EPERM``
+     - This aspect cannot be modified with prctl() (check for the
+       PR_PPC_DEXCR_CTRL_EDITABLE flag with PR_PPC_GET_DEXCR).
+
+   * - ``EPERM``
+     - The process does not have sufficient privilege to perform the operation.
+       For example, clearing NPHIE on exec is a privileged operation (a process
+       can still clear its own NPHIE aspect without privileges).
+
+This interface allows a process to control its own DEXCR aspects, and also set
+the initial DEXCR value for any children in its process tree (up to the next
+child to use an ``*_ONEXEC`` control). This allows fine-grained control over the
+default value of the DEXCR, for example allowing containers to run with different
+default values.
 
 
 coredump and ptrace