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2024-06-17x86/apic: Mark acpi_mp_wake_* variables as __ro_after_initKirill A. Shutemov
acpi_mp_wake_mailbox_paddr and acpi_mp_wake_mailbox are initialized once during ACPI MADT init and never changed. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kai Huang <kai.huang@intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Tao Liu <ltao@redhat.com> Link: https://lore.kernel.org/r/20240614095904.1345461-3-kirill.shutemov@linux.intel.com
2024-06-17x86/acpi: Extract ACPI MADT wakeup code into a separate fileKirill A. Shutemov
In order to prepare for the expansion of support for the ACPI MADT wakeup method, move the relevant code into a separate file. Introduce a new configuration option to clearly indicate dependencies without the use of ifdefs. There have been no functional changes. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Baoquan He <bhe@redhat.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Kai Huang <kai.huang@intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Tao Liu <ltao@redhat.com> Link: https://lore.kernel.org/r/20240614095904.1345461-2-kirill.shutemov@linux.intel.com
2024-03-13Merge tag 'acpi-6.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These modify the ACPI device events and processor enumeration code to take the 'enabled' _STA bit into account as mandated by the ACPI specification, convert several platform drivers to using a remove callback that returns void, add some new quirks for ACPI IRQ override and other things, address assorted issues and clean up code. Specifics: - Rearrange Device Check and Bus Check notification handling in the ACPI device hotplug code to make it get the "enabled" _STA bit into account (Rafael Wysocki) - Modify acpi_processor_add() to skip processors with the "enabled" _STA bit clear, as per the specification (Rafael Wysocki) - Stop failing Device Check notification handling without a valid reason (Rafael Wysocki) - Defer enumeration of devices that depend on a device with an ACPI device ID equalt to INTC10CF to address probe ordering issues on some platforms (Wentong Wu) - Constify acpi_bus_type (Ricardo Marliere) - Make the ACPI-specific suspend-to-idle code take the Low-Power S0 Idle MSFT UUID into account on non-AMD systems (Rafael Wysocki) - Add ACPI IRQ override quirks for some new platforms (Sergey Kalinichev, Maxim Kudinov, Alexey Froloff, Sviatoslav Harasymchuk, Nicolas Haye) - Make the NFIT parsing code use acpi_evaluate_dsm_typed() (Andy Shevchenko) - Fix a memory leak in acpi_processor_power_exit() (Armin Wolf) - Make it possible to quirk the CSI-2 and MIPI DisCo for Imaging properties parsing and add a quirk for Dell XPS 9315 (Sakari Ailus) - Prevent false-positive static checker warnings from triggering by intializing some variables in the ACPI thermal code to zero (Colin Ian King) - Add DELL0501 handling to acpi_quirk_skip_serdev_enumeration() and make that function generic (Hans de Goede) - Make the ACPI backlight code handle fetching EDID that is longer than 256 bytes (Mario Limonciello) - Skip initialization of GHES_ASSIST structures for Machine Check Architecture in APEI (Avadhut Naik) - Convert several plaform drivers in the ACPI subsystem to using a remove callback that returns void (Uwe Kleine-König) - Drop the long-deprecated custom_method debugfs interface that is problematic from the security standpoint (Rafael Wysocki) - Use %pe in a couple of places in the ACPI code for easier error decoding (Onkarnath) - Fix register width information handling during system memory accesses in the ACPI CPPC library (Jarred White) - Add AMD CPPC V2 support for family 17h processors to the ACPI CPPC library (Perry Yuan)" * tag 'acpi-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits) ACPI: resource: Use IRQ override on Maibenben X565 ACPI: CPPC: Use access_width over bit_width for system memory accesses ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors ACPI: APEI: Skip initialization of GHES_ASSIST structures for Machine Check Architecture ACPI: scan: Consolidate Device Check and Bus Check notification handling ACPI: scan: Rework Device Check and Bus Check notification handling ACPI: scan: Make acpi_processor_add() check the device enabled bit ACPI: scan: Relocate acpi_bus_trim_one() ACPI: scan: Fix device check notification handling ACPI: resource: Add MAIBENBEN X577 to irq1_edge_low_force_override ACPI: pfr_update: Convert to platform remove callback returning void ACPI: pfr_telemetry: Convert to platform remove callback returning void ACPI: fan: Convert to platform remove callback returning void ACPI: GED: Convert to platform remove callback returning void ACPI: DPTF: Convert to platform remove callback returning void ACPI: AGDI: Convert to platform remove callback returning void ACPI: TAD: Convert to platform remove callback returning void ACPI: APEI: GHES: Convert to platform remove callback returning void ACPI: property: Polish ignoring bad data nodes ACPI: thermal_lib: Initialize temp_decik to zero ...
2024-03-13Merge tag 'pm-6.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "From the functional perspective, the most significant change here is the addition of support for Energy Models that can be updated dynamically at run time. There is also the addition of LZ4 compression support for hibernation, the new preferred core support in amd-pstate, new platforms support in the Intel RAPL driver, new model-specific EPP handling in intel_pstate and more. Apart from that, the cpufreq default transition delay is reduced from 10 ms to 2 ms (along with some related adjustments), the system suspend statistics code undergoes a significant rework and there is a usual bunch of fixes and code cleanups all over. Specifics: - Allow the Energy Model to be updated dynamically (Lukasz Luba) - Add support for LZ4 compression algorithm to the hibernation image creation and loading code (Nikhil V) - Fix and clean up system suspend statistics collection (Rafael Wysocki) - Simplify device suspend and resume handling in the power management core code (Rafael Wysocki) - Fix PCI hibernation support description (Yiwei Lin) - Make hibernation take set_memory_ro() return values into account as appropriate (Christophe Leroy) - Set mem_sleep_current during kernel command line setup to avoid an ordering issue with handling it (Maulik Shah) - Fix wake IRQs handling when pm_runtime_force_suspend() is used as a driver's system suspend callback (Qingliang Li) - Simplify pm_runtime_get_if_active() usage and add a replacement for pm_runtime_put_autosuspend() (Sakari Ailus) - Add a tracepoint for runtime_status changes tracking (Vilas Bhat) - Fix section title markdown in the runtime PM documentation (Yiwei Lin) - Enable preferred core support in the amd-pstate cpufreq driver (Meng Li) - Fix min_perf assignment in amd_pstate_adjust_perf() and make the min/max limit perf values in amd-pstate always stay within the (highest perf, lowest perf) range (Tor Vic, Meng Li) - Allow intel_pstate to assign model-specific values to strings used in the EPP sysfs interface and make it do so on Meteor Lake (Srinivas Pandruvada) - Drop long-unused cpudata::prev_cummulative_iowait from the intel_pstate cpufreq driver (Jiri Slaby) - Prevent scaling_cur_freq from exceeding scaling_max_freq when the latter is an inefficient frequency (Shivnandan Kumar) - Change default transition delay in cpufreq to 2ms (Qais Yousef) - Remove references to 10ms minimum sampling rate from comments in the cpufreq code (Pierre Gondois) - Honour transition_latency over transition_delay_us in cpufreq (Qais Yousef) - Stop unregistering cpufreq cooling on CPU hot-remove (Viresh Kumar) - General enhancements / cleanups to ARM cpufreq drivers (tianyu2, Nícolas F. R. A. Prado, Erick Archer, Arnd Bergmann, Anastasia Belova) - Update cpufreq-dt-platdev to block/approve devices (Richard Acayan) - Make the SCMI cpufreq driver get a transition delay value from firmware (Pierre Gondois) - Prevent the haltpoll cpuidle governor from shrinking guest poll_limit_ns below grow_start (Parshuram Sangle) - Avoid potential overflow in integer multiplication when computing cpuidle state parameters (C Cheng) - Adjust MWAIT hint target C-state computation in the ACPI cpuidle driver and in intel_idle to return a correct value for C0 (He Rongguang) - Address multiple issues in the TPMI RAPL driver and add support for new platforms (Lunar Lake-M, Arrow Lake) to Intel RAPL (Zhang Rui) - Fix freq_qos_add_request() return value check in dtpm_cpu (Daniel Lezcano) - Fix kernel-doc for dtpm_create_hierarchy() (Yang Li) - Fix file leak in get_pkg_num() in x86_energy_perf_policy (Samasth Norway Ananda) - Fix cpupower-frequency-info.1 man page typo (Jan Kratochvil) - Fix a couple of warnings in the OPP core code related to W=1 builds (Viresh Kumar) - Move dev_pm_opp_{init|free}_cpufreq_table() to pm_opp.h (Viresh Kumar) - Extend dev_pm_opp_data with turbo support (Sibi Sankar) - dt-bindings: drop maxItems from inner items (David Heidelberg)" * tag 'pm-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (95 commits) dt-bindings: opp: drop maxItems from inner items OPP: debugfs: Fix warning around icc_get_name() OPP: debugfs: Fix warning with W=1 builds cpufreq: Move dev_pm_opp_{init|free}_cpufreq_table() to pm_opp.h OPP: Extend dev_pm_opp_data with turbo support Fix cpupower-frequency-info.1 man page typo cpufreq: scmi: Set transition_delay_us firmware: arm_scmi: Populate fast channel rate_limit firmware: arm_scmi: Populate perf commands rate_limit cpuidle: ACPI/intel: fix MWAIT hint target C-state computation PM: sleep: wakeirq: fix wake irq warning in system suspend powercap: dtpm: Fix kernel-doc for dtpm_create_hierarchy() function cpufreq: Don't unregister cpufreq cooling on CPU hotplug PM: suspend: Set mem_sleep_current during kernel command line setup cpufreq: Honour transition_latency over transition_delay_us cpufreq: Limit resolving a frequency to policy min/max Documentation: PM: Fix runtime_pm.rst markdown syntax cpufreq: amd-pstate: adjust min/max limit perf cpufreq: Remove references to 10ms min sampling rate cpufreq: intel_pstate: Update default EPPs for Meteor Lake ...
2024-03-11Merge tag 'x86-core-2024-03-11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: - The biggest change is the rework of the percpu code, to support the 'Named Address Spaces' GCC feature, by Uros Bizjak: - This allows C code to access GS and FS segment relative memory via variables declared with such attributes, which allows the compiler to better optimize those accesses than the previous inline assembly code. - The series also includes a number of micro-optimizations for various percpu access methods, plus a number of cleanups of %gs accesses in assembly code. - These changes have been exposed to linux-next testing for the last ~5 months, with no known regressions in this area. - Fix/clean up __switch_to()'s broken but accidentally working handling of FPU switching - which also generates better code - Propagate more RIP-relative addressing in assembly code, to generate slightly better code - Rework the CPU mitigations Kconfig space to be less idiosyncratic, to make it easier for distros to follow & maintain these options - Rework the x86 idle code to cure RCU violations and to clean up the logic - Clean up the vDSO Makefile logic - Misc cleanups and fixes * tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) x86/idle: Select idle routine only once x86/idle: Let prefer_mwait_c1_over_halt() return bool x86/idle: Cleanup idle_setup() x86/idle: Clean up idle selection x86/idle: Sanitize X86_BUG_AMD_E400 handling sched/idle: Conditionally handle tick broadcast in default_idle_call() x86: Increase brk randomness entropy for 64-bit systems x86/vdso: Move vDSO to mmap region x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o x86/retpoline: Ensure default return thunk isn't used at runtime x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32 x86/vdso: Use $(addprefix ) instead of $(foreach ) x86/vdso: Simplify obj-y addition x86/vdso: Consolidate targets and clean-files x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS ...
2024-03-05cpuidle: ACPI/intel: fix MWAIT hint target C-state computationHe Rongguang
According to x86 spec ([1] and [2]), MWAIT hint_address[7:4] plus 1 is the corresponding C-state, and 0xF means C0. ACPI C-state table usually only contains C1+, but nothing prevents ACPI firmware from presenting a C-state (maybe C1+) but using MWAIT address C0 (i.e., 0xF in ACPI FFH MWAIT hint address). And if this is the case, Linux erroneously treat this cstate as C16, while actually this should be valid C0 instead of C16, as per the specifications. Since ACPI firmware is out of Linux kernel scope, fix the kernel handling of 0xF ->(to) C0 in this situation. This is found when a tweaked ACPI C-state table is presented by Qemu to VM. Also modify the intel_idle case for code consistency. [1]. Intel SDM Vol 2, Table 4-11. MWAIT Hints Register (EAX): "Value of 0 means C1; 1 means C2 and so on Value of 01111B means C0". [2]. AMD manual Vol 3, MWAIT: "The processor C-state is EAX[7:4]+1, so to request C0 is to place the value F in EAX[7:4] and to request C1 is to place the value 0 in EAX[7:4].". Signed-off-by: He Rongguang <herongguang@linux.alibaba.com> [ rjw: Subject and changelog edits, whitespace fixups ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-03-05ACPI: CPPC: enable AMD CPPC V2 support for family 17h processorsPerry Yuan
As there are some AMD processors which only support CPPC V2 firmware and BIOS implementation, the amd_pstate driver will be failed to load when system booting with below kernel warning message: [ 0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled To make the amd_pstate driver can be loaded on those TR40 processors, it needs to match x86_model from 0x30 to 0x7F for family 17H. With the change, the system can load amd_pstate driver as expected. Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Reported-by: Gino Badouri <badouri.g@gmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218171 Fixes: fbd74d1689 ("ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memory") Signed-off-by: Perry Yuan <perry.yuan@amd.com> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2024-02-15x86/cpu/topology: Let XEN/PV use topology from CPUID/MADTThomas Gleixner
It turns out that XEN/PV Dom0 has halfways usable CPUID/MADT enumeration except that it cannot deal with CPUs which are enumerated as disabled in MADT. DomU has no MADT and provides at least rudimentary topology information in CPUID leaves 1 and 4. For both it's important that there are not more possible Linux CPUs than vCPUs provided by the hypervisor. As this is ensured by counting the vCPUs before enumeration happens: - lift the restrictions in the CPUID evaluation and the MADT parser - Utilize MADT registration for Dom0 - Keep the fake APIC ID registration for DomU - Fix the XEN APIC fake so the readout of the local APIC ID works for Dom0 via the hypercall and for DomU by returning the registered fake APIC IDs. With that the XEN/PV fake approximates usefulness. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210252.626195405@linutronix.de
2024-02-15x86/acpi: Dont invoke topology_register_apic() for XEN PVThomas Gleixner
The MADT table for XEN/PV dom0 is not really useful and registering the APICs is momentarily a pointless exercise because XENPV does not use an APIC at all. It overrides the x86_init.mpparse.parse_smp_config() callback, resets num_processors and counts how many of them are provided by the hypervisor. This is in the way of cleaning up the APIC registration. Prevent MADT registration for XEN/PV temporarily until the rework is completed and XEN/PV can use the MADT again. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210251.885489468@linutronix.de
2024-02-15x86/acpi: Use new APIC registration functionsThomas Gleixner
Use the new topology registration functions and make the early boot code path __init. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210251.664738831@linutronix.de
2024-02-14Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the ↵Ingo Molnar
branch Conflicts: arch/x86/include/asm/percpu.h arch/x86/include/asm/text-patching.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-12-18x86/acpi: Handle bogus MADT APIC tables gracefullyThomas Gleixner
The recent fix to ignore invalid x2APIC entries inadvertently broke systems with creative MADT APIC tables. The affected systems have APIC MADT tables where all entries have invalid APIC IDs (0xFF), which means they register exactly zero CPUs. But the condition to ignore the entries of APIC IDs < 255 in the X2APIC MADT table is solely based on the count of MADT APIC table entries. As a consequence, the affected machines enumerate no secondary CPUs at all because the APIC table has entries and therefore the X2APIC table entries with APIC IDs < 255 are ignored. Change the condition so that the APIC table preference for APIC IDs < 255 only becomes effective when the APIC table has valid APIC ID entries. IOW, an APIC table full of invalid APIC IDs is considered to be empty which in consequence enables the X2APIC table entries with a APIC ID < 255 and restores the expected behaviour. Fixes: ec9aedb2aa1a ("x86/acpi: Ignore invalid x2APIC entries") Reported-by: John Sperbeck <jsperbeck@google.com> Reported-by: Andres Freund <andres@anarazel.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/169953729188.3135.6804572126118798018.tip-bot2@tip-bot2
2023-11-30x86/acpi: Use %rip-relative addressing in wakeup_64.SUros Bizjak
This is a "nice-to-have" change with minor code generation benefits: - Instruction with %rip-relative address operand is one byte shorter than its absolute address counterpart, - it is also compatible with position independent executable (-fpie) builds, - it is also consistent with what the compiler emits by default when a symbol is accessed. No functional changes intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20231103104900.409470-1-ubizjak@gmail.com
2023-11-19Merge tag 'x86_urgent_for_v6.7_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Ignore invalid x2APIC entries in order to not waste per-CPU data - Fix a back-to-back signals handling scenario when shadow stack is in use - A documentation fix - Add Kirill as TDX maintainer * tag 'x86_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/acpi: Ignore invalid x2APIC entries x86/shstk: Delay signal entry SSP write until after user accesses x86/Documentation: Indent 'note::' directive for protocol version number note MAINTAINERS: Add Intel TDX entry
2023-11-09x86/acpi: Ignore invalid x2APIC entriesZhang Rui
Currently, the kernel enumerates the possible CPUs by parsing both ACPI MADT Local APIC entries and x2APIC entries. So CPUs with "valid" APIC IDs, even if they have duplicated APIC IDs in Local APIC and x2APIC, are always enumerated. Below is what ACPI MADT Local APIC and x2APIC describes on an Ivebridge-EP system, [02Ch 0044 1] Subtable Type : 00 [Processor Local APIC] [02Fh 0047 1] Local Apic ID : 00 ... [164h 0356 1] Subtable Type : 00 [Processor Local APIC] [167h 0359 1] Local Apic ID : 39 [16Ch 0364 1] Subtable Type : 00 [Processor Local APIC] [16Fh 0367 1] Local Apic ID : FF ... [3ECh 1004 1] Subtable Type : 09 [Processor Local x2APIC] [3F0h 1008 4] Processor x2Apic ID : 00000000 ... [B5Ch 2908 1] Subtable Type : 09 [Processor Local x2APIC] [B60h 2912 4] Processor x2Apic ID : 00000077 As a result, kernel shows "smpboot: Allowing 168 CPUs, 120 hotplug CPUs". And this wastes significant amount of memory for the per-cpu data. Plus this also breaks https://lore.kernel.org/all/87edm36qqb.ffs@tglx/, because __max_logical_packages is over-estimated by the APIC IDs in the x2APIC entries. According to https://uefi.org/specs/ACPI/6.5/05_ACPI_Software_Programming_Model.html#processor-local-x2apic-structure: "[Compatibility note] On some legacy OSes, Logical processors with APIC ID values less than 255 (whether in XAPIC or X2APIC mode) must use the Processor Local APIC structure to convey their APIC information to OSPM, and those processors must be declared in the DSDT using the Processor() keyword. Logical processors with APIC ID values 255 and greater must use the Processor Local x2APIC structure and be declared using the Device() keyword." Therefore prevent the registration of x2APIC entries with an APIC ID less than 255 if the local APIC table enumerates valid APIC IDs. [ tglx: Simplify the logic ] Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230702162802.344176-1-rui.zhang@intel.com
2023-10-30Merge tag 'x86-core-2023-10-29-v2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Thomas Gleixner: - Limit the hardcoded topology quirk for Hygon CPUs to those which have a model ID less than 4. The newer models have the topology CPUID leaf 0xB correctly implemented and are not affected. - Make SMT control more robust against enumeration failures SMT control was added to allow controlling SMT at boottime or runtime. The primary purpose was to provide a simple mechanism to disable SMT in the light of speculation attack vectors. It turned out that the code is sensible to enumeration failures and worked only by chance for XEN/PV. XEN/PV has no real APIC enumeration which means the primary thread mask is not set up correctly. By chance a XEN/PV boot ends up with smp_num_siblings == 2, which makes the hotplug control stay at its default value "enabled". So the mask is never evaluated. The ongoing rework of the topology evaluation caused XEN/PV to end up with smp_num_siblings == 1, which sets the SMT control to "not supported" and the empty primary thread mask causes the hotplug core to deny the bringup of the APS. Make the decision logic more robust and take 'not supported' and 'not implemented' into account for the decision whether a CPU should be booted or not. - Fake primary thread mask for XEN/PV Pretend that all XEN/PV vCPUs are primary threads, which makes the usage of the primary thread mask valid on XEN/PV. That is consistent with because all of the topology information on XEN/PV is fake or even non-existent. - Encapsulate topology information in cpuinfo_x86 Move the randomly scattered topology data into a separate data structure for readability and as a preparatory step for the topology evaluation overhaul. - Consolidate APIC ID data type to u32 It's fixed width hardware data and not randomly u16, int, unsigned long or whatever developers decided to use. - Cure the abuse of cpuinfo for persisting logical IDs. Per CPU cpuinfo is used to persist the logical package and die IDs. That's really not the right place simply because cpuinfo is subject to be reinitialized when a CPU goes through an offline/online cycle. Use separate per CPU data for the persisting to enable the further topology management rework. It will be removed once the new topology management is in place. - Provide a debug interface for inspecting topology information Useful in general and extremly helpful for validating the topology management rework in terms of correctness or "bug" compatibility. * tag 'x86-core-2023-10-29-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/apic, x86/hyperv: Use u32 in hv_snp_boot_ap() too x86/cpu: Provide debug interface x86/cpu/topology: Cure the abuse of cpuinfo for persisting logical ids x86/apic: Use u32 for wakeup_secondary_cpu[_64]() x86/apic: Use u32 for [gs]et_apic_id() x86/apic: Use u32 for phys_pkg_id() x86/apic: Use u32 for cpu_present_to_apicid() x86/apic: Use u32 for check_apicid_used() x86/apic: Use u32 for APIC IDs in global data x86/apic: Use BAD_APICID consistently x86/cpu: Move cpu_l[l2]c_id into topology info x86/cpu: Move logical package and die IDs into topology info x86/cpu: Remove pointless evaluation of x86_coreid_bits x86/cpu: Move cu_id into topology info x86/cpu: Move cpu_core_id into topology info hwmon: (fam15h_power) Use topology_core_id() scsi: lpfc: Use topology_core_id() x86/cpu: Move cpu_die_id into topology info x86/cpu: Move phys_proc_id into topology info x86/cpu: Encapsulate topology information in cpuinfo_x86 ...
2023-10-27x86/i8259: Skip probing when ACPI/MADT advertises PCAT compatibilityThomas Gleixner
David and a few others reported that on certain newer systems some legacy interrupts fail to work correctly. Debugging revealed that the BIOS of these systems leaves the legacy PIC in uninitialized state which makes the PIC detection fail and the kernel switches to a dummy implementation. Unfortunately this fallback causes quite some code to fail as it depends on checks for the number of legacy PIC interrupts or the availability of the real PIC. In theory there is no reason to use the PIC on any modern system when IO/APIC is available, but the dependencies on the related checks cannot be resolved trivially and on short notice. This needs lots of analysis and rework. The PIC detection has been added to avoid quirky checks and force selection of the dummy implementation all over the place, especially in VM guest scenarios. So it's not an option to revert the relevant commit as that would break a lot of other scenarios. One solution would be to try to initialize the PIC on detection fail and retry the detection, but that puts the burden on everything which does not have a PIC. Fortunately the ACPI/MADT table header has a flag field, which advertises in bit 0 that the system is PCAT compatible, which means it has a legacy 8259 PIC. Evaluate that bit and if set avoid the detection routine and keep the real PIC installed, which then gets initialized (for nothing) and makes the rest of the code with all the dependencies work again. Fixes: e179f6914152 ("x86, irq, pic: Probe for legacy PIC and set legacy_pic appropriately") Reported-by: David Lazar <dlazar@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: David Lazar <dlazar@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Cc: stable@vger.kernel.org Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218003 Link: https://lore.kernel.org/r/875y2u5s8g.ffs@tglx
2023-10-10x86/apic: Use u32 for wakeup_secondary_cpu[_64]()Thomas Gleixner
APIC IDs are used with random data types u16, u32, int, unsigned int, unsigned long. Make it all consistently use u32 because that reflects the hardware register width. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085113.233274223@linutronix.de
2023-10-10x86/apic: Use BAD_APICID consistentlyThomas Gleixner
APIC ID checks compare with BAD_APICID all over the place, but some initializers and some code which fiddles with global data structure use -1[U] instead. That simply cannot work at all. Fix it up and use BAD_APICID consistently all over the place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.862835121@linutronix.de
2023-08-30Merge tag 'x86_apic_for_6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Dave Hansen: "This includes a very thorough rework of the 'struct apic' handlers. Quite a variety of them popped up over the years, especially in the 32-bit days when odd apics were much more in vogue. The end result speaks for itself, which is a removal of a ton of code and static calls to replace indirect calls. If there's any breakage here, it's likely to be around the 32-bit museum pieces that get light to no testing these days. Summary: - Rework apic callbacks, getting rid of unnecessary ones and coalescing lots of silly duplicates. - Use static_calls() instead of indirect calls for apic->foo() - Tons of cleanups an crap removal along the way" * tag 'x86_apic_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) x86/apic: Turn on static calls x86/apic: Provide static call infrastructure for APIC callbacks x86/apic: Wrap IPI calls into helper functions x86/apic: Mark all hotpath APIC callback wrappers __always_inline x86/xen/apic: Mark apic __ro_after_init x86/apic: Convert other overrides to apic_update_callback() x86/apic: Replace acpi_wake_cpu_handler_update() and apic_set_eoi_cb() x86/apic: Provide apic_update_callback() x86/xen/apic: Use standard apic driver mechanism for Xen PV x86/apic: Provide common init infrastructure x86/apic: Wrap apic->native_eoi() into a helper x86/apic: Nuke ack_APIC_irq() x86/apic: Remove pointless arguments from [native_]eoi_write() x86/apic/noop: Tidy up the code x86/apic: Remove pointless NULL initializations x86/apic: Sanitize APIC ID range validation x86/apic: Prepare x2APIC for using apic::max_apic_id x86/apic: Simplify X2APIC ID validation x86/apic: Add max_apic_id member x86/apic: Wrap APIC ID validation into an inline ...
2023-08-09ACPI: resource: Honor MADT INT_SRC_OVR settings for IRQ1 on AMD ZenHans de Goede
On AMD Zen acpi_dev_irq_override() by default prefers the DSDT IRQ 1 settings over the MADT settings. This causes the keyboard to malfunction on some laptop models (see Links), all models from the Links have an INT_SRC_OVR MADT entry for IRQ 1. Fixes: a9c4a912b7dc ("ACPI: resource: Remove "Zen" specific match and quirks") Link: https://bugzilla.kernel.org/show_bug.cgi?id=217336 Link: https://bugzilla.kernel.org/show_bug.cgi?id=217394 Link: https://bugzilla.kernel.org/show_bug.cgi?id=217406 Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-08-09x86/apic: Replace acpi_wake_cpu_handler_update() and apic_set_eoi_cb()Thomas Gleixner
Switch them over to apic_update_callback() and remove the code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Wei Liu <wei.liu@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-08-09x86/apic: Wrap APIC ID validation into an inlineThomas Gleixner
Prepare for removing the callback and making this as simple comparison to an upper limit, which is the obvious solution to do for limit checks... Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-08-09x86/apic: Remove the pointless APIC version checkThomas Gleixner
This historical leftover is really uninteresting today. Whatever MPTABLE or MADT delivers we only trust the hardware anyway. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-08-09x86/apic/ioapic: Rename skip_ioapic_setupThomas Gleixner
Another variable name which is confusing at best. Convert to bool. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
2023-06-26Merge tag 'x86_cleanups_for_6.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Dave Hansen: "As usual, these are all over the map. The biggest cluster is work from Arnd to eliminate -Wmissing-prototype warnings: - Address -Wmissing-prototype warnings - Remove repeated 'the' in comments - Remove unused current_untag_mask() - Document urgent tip branch timing - Clean up MSR kernel-doc notation - Clean up paravirt_ops doc - Update Srivatsa S. Bhat's maintained areas - Remove unused extern declaration acpi_copy_wakeup_routine()" * tag 'x86_cleanups_for_6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) x86/acpi: Remove unused extern declaration acpi_copy_wakeup_routine() Documentation: virt: Clean up paravirt_ops doc x86/mm: Remove unused current_untag_mask() x86/mm: Remove repeated word in comments x86/lib/msr: Clean up kernel-doc notation x86/platform: Avoid missing-prototype warnings for OLPC x86/mm: Add early_memremap_pgprot_adjust() prototype x86/usercopy: Include arch_wb_cache_pmem() declaration x86/vdso: Include vdso/processor.h x86/mce: Add copy_mc_fragile_handle_tail() prototype x86/fbdev: Include asm/fb.h as needed x86/hibernate: Declare global functions in suspend.h x86/entry: Add do_SYSENTER_32() prototype x86/quirks: Include linux/pnp.h for arch_pnpbios_disabled() x86/mm: Include asm/numa.h for set_highmem_pages_init() x86: Avoid missing-prototype warnings for doublefault code x86/fpu: Include asm/fpu/regset.h x86: Add dummy prototype for mk_early_pgtbl_32() x86/pci: Mark local functions as 'static' x86/ftrace: Move prepare_ftrace_return prototype to header ...
2023-06-21x86/acpi: Remove unused extern declaration acpi_copy_wakeup_routine()YueHaibing
This is now unused, so can be removed. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/all/20230620094519.15300-1-yuehaibing%40huawei.com
2023-05-15x86/smpboot: Support parallel startup of secondary CPUsDavid Woodhouse
In parallel startup mode the APs are kicked alive by the control CPU quickly after each other and run through the early startup code in parallel. The real-mode startup code is already serialized with a bit-spinlock to protect the real-mode stack. In parallel startup mode the smpboot_control variable obviously cannot contain the Linux CPU number so the APs have to determine their Linux CPU number on their own. This is required to find the CPUs per CPU offset in order to find the idle task stack and other per CPU data. To achieve this, export the cpuid_to_apicid[] array so that each AP can find its own CPU number by searching therein based on its APIC ID. Introduce a flag in the top bits of smpboot_control which indicates that the AP should find its CPU number by reading the APIC ID from the APIC. This is required because CPUID based APIC ID retrieval can only provide the initial APIC ID, which might have been overruled by the firmware. Some AMD APUs come up with APIC ID = initial APIC ID + 0x10, so the APIC ID to CPU number lookup would fail miserably if based on CPUID. Also virtualization can make its own APIC ID assignements. The only requirement is that the APIC IDs are consistent with the APCI/MADT table. For the boot CPU or in case parallel bringup is disabled the control bits are empty and the CPU number is directly available in bit 0-23 of smpboot_control. [ tglx: Initial proof of concept patch with bitlock and APIC ID lookup ] [ dwmw2: Rework and testing, commit message, CPUID 0x1 and CPU0 support ] [ seanc: Fix stray override of initial_gs in common_cpu_up() ] [ Oleksandr Natalenko: reported suspend/resume issue fixed in x86_acpi_suspend_lowlevel ] [ tglx: Make it read the APIC ID from the APIC instead of using CPUID, split the bitlock part out ] Co-developed-by: Thomas Gleixner <tglx@linutronix.de> Co-developed-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205257.411554373@linutronix.de
2023-04-25Merge tag 'x86-apic-2023-04-24' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Thomas Gleixner: - Fix the incorrect handling of atomic offset updates in reserve_eilvt_offset() The check for the return value of atomic_cmpxchg() is not compared against the old value, it is compared against the new value, which makes it two round on success. Convert it to atomic_try_cmpxchg() which does the right thing. - Handle IO/APIC less systems correctly When IO/APIC is not advertised by ACPI then the computation of the lower bound for dynamically allocated interrupts like MSI goes wrong. This lower bound is used to exclude the IO/APIC legacy GSI space as that must stay reserved for the legacy interrupts. In case that the system, e.g. VM, does not advertise an IO/APIC the lower bound stays at 0. 0 is an invalid interrupt number except for the legacy timer interrupt on x86. The return value is unchecked in the core code, so it ends up to allocate interrupt number 0 which is subsequently considered to be invalid by the caller, e.g. the MSI allocation code. A similar problem was already cured for device tree based systems years ago, but that missed - or did not envision - the zero IO/APIC case. Consolidate the zero check and return the provided "from" argument to the core code call site, which is guaranteed to be greater than 0. - Simplify the X2APIC cluster CPU mask logic for CPU hotplug Per cluster CPU masks are required for X2APIC in cluster mode to determine the correct cluster for a target CPU when calculating the destination for IPIs These masks are established when CPUs are borught up. The first CPU in a cluster must allocate a new cluster CPU mask. As this happens during the early startup of a CPU, where memory allocations cannot be done, the mask has to be allocated by the control CPU. The current implementation allocates a clustermask just in case and if the to be brought up CPU is the first in a cluster the CPU takes over this allocation from a global pointer. This works nicely in the fully serialized CPU bringup scenario which is used today, but would fail completely for parallel bringup of CPUs. The cluster association of a CPU can be computed from the APIC ID which is enumerated by ACPI/MADT. So the cluster CPU masks can be preallocated and associated upfront and the upcoming CPUs just need to set their corresponding bit. Aside of preparing for parallel bringup this is a valuable simplification on its own. - Remove global variables which control the early startup of secondary CPUs on 64-bit The only information which is needed by a starting CPU is the Linux CPU number. The CPU number allows it to retrieve the rest of the required data from already existing per CPU storage. So instead of initial_stack, early_gdt_desciptor and initial_gs provide a new variable smpboot_control which contains the Linux CPU number for now. The starting CPU can retrieve and compute all required information for startup from there. Aside of being a cleanup, this is also preparing for parallel CPU bringup, where starting CPUs will look up their Linux CPU number via the APIC ID, when smpboot_control has the corresponding control bit set. - Make cc_vendor globally accesible Subsequent parallel bringup changes require access to cc_vendor because confidental computing platforms need special treatment in the early startup phase vs. CPUID and APCI ID readouts. The change makes cc_vendor global and provides stub accessors in case that CONFIG_ARCH_HAS_CC_PLATFORM is not set. This was merged from the x86/cc branch in anticipation of further parallel bringup commits which require access to cc_vendor. Due to late discoveries of fundamental issue with those patches these commits never happened. The merge commit is unfortunately in the middle of the APIC commits so unraveling it would have required a rebase or revert. As the parallel bringup seems to be well on its way for 6.5 this would be just pointless churn. As the commit does not contain any functional change it's not a risk to keep it. * tag 'x86-apic-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ioapic: Don't return 0 from arch_dynirq_lower_bound() x86/apic: Fix atomic update of offset in reserve_eilvt_offset() x86/coco: Export cc_vendor x86/smpboot: Reference count on smpboot_setup_warm_reset_vector() x86/smpboot: Remove initial_gs x86/smpboot: Remove early_gdt_descr on 64-bit x86/smpboot: Remove initial_stack on 64-bit x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel
2023-04-25Merge tag 'x86_acpi_for_v6.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 ACPI update from Borislav Petkov: - Improve code generation in ACPI's global lock's acquisition function * tag 'x86_acpi_for_v6.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ACPI/boot: Improve __acpi_acquire_global_lock
2023-03-30x86/acpi/boot: Correct acpi_is_processor_usable() checkEric DeVolder
The logic in acpi_is_processor_usable() requires the online capable bit be set for hotpluggable CPUs. The online capable bit has been introduced in ACPI 6.3. However, for ACPI revisions < 6.3 which do not support that bit, CPUs should be reported as usable, not the other way around. Reverse the check. [ bp: Rewrite commit message. ] Fixes: e2869bd7af60 ("x86/acpi/boot: Do not register processors that cannot be onlined for x2APIC") Suggested-by: Miguel Luis <miguel.luis@oracle.com> Suggested-by: Boris Ostrovsky <boris.ovstrosky@oracle.com> Signed-off-by: Eric DeVolder <eric.devolder@oracle.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: David R <david@unsolicited.net> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/20230327191026.3454-2-eric.devolder@oracle.com
2023-03-30x86/ACPI/boot: Use FADT version to check support for online capableMario Limonciello
ACPI 6.3 introduced the online capable bit, and also introduced MADT version 5. Latter was used to distinguish whether the offset storing online capable could be used. However ACPI 6.2b has MADT version "45" which is for an errata version of the ACPI 6.2 spec. This means that the Linux code for detecting availability of MADT will mistakenly flag ACPI 6.2b as supporting online capable which is inaccurate as it's an ACPI 6.3 feature. Instead use the FADT major and minor revision fields to distinguish this. [ bp: Massage. ] Fixes: aa06e20f1be6 ("x86/ACPI: Don't add CPUs that are not online capable") Reported-by: Eric DeVolder <eric.devolder@oracle.com> Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@kernel.org> Link: https://lore.kernel.org/r/943d2445-84df-d939-f578-5d8240d342cc@unsolicited.net
2023-03-22x86/ACPI/boot: Improve __acpi_acquire_global_lockUros Bizjak
Improve __acpi_acquire_global_lock by using a temporary variable. This enables compiler to perform if-conversion and improves generated code from: ... 72a: d1 ea shr %edx 72c: 83 e1 fc and $0xfffffffc,%ecx 72f: 83 e2 01 and $0x1,%edx 732: 09 ca or %ecx,%edx 734: 83 c2 02 add $0x2,%edx 737: f0 0f b1 17 lock cmpxchg %edx,(%rdi) 73b: 75 e9 jne 726 <__acpi_acquire_global_lock+0x6> 73d: 83 e2 03 and $0x3,%edx 740: 31 c0 xor %eax,%eax 742: 83 fa 03 cmp $0x3,%edx 745: 0f 95 c0 setne %al 748: f7 d8 neg %eax to: ... 72a: d1 e9 shr %ecx 72c: 83 e2 fc and $0xfffffffc,%edx 72f: 83 e1 01 and $0x1,%ecx 732: 09 ca or %ecx,%edx 734: 83 c2 02 add $0x2,%edx 737: f0 0f b1 17 lock cmpxchg %edx,(%rdi) 73b: 75 e9 jne 726 <__acpi_acquire_global_lock+0x6> 73d: 8d 41 ff lea -0x1(%rcx),%eax BTW: the compiler could generate: lea 0x2(%rcx,%rdx,1),%edx instead of: or %ecx,%edx add $0x2,%edx but unwated conversion from add to or when bits are known to be zero prevents this improvement. This is GCC PR108477. No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/all/20230320212012.12704-1-ubizjak%40gmail.com
2023-03-21x86/smpboot: Remove initial_gsBrian Gerst
Given its CPU#, each CPU can find its own per-cpu offset, and directly set GSBASE accordingly. The global variable can be eliminated. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Usama Arif <usama.arif@bytedance.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Usama Arif <usama.arif@bytedance.com> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20230316222109.1940300-9-usama.arif@bytedance.com
2023-03-21x86/smpboot: Remove early_gdt_descr on 64-bitBrian Gerst
Build the GDT descriptor on the stack instead. Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Usama Arif <usama.arif@bytedance.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Usama Arif <usama.arif@bytedance.com> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20230316222109.1940300-8-usama.arif@bytedance.com
2023-03-21x86/smpboot: Remove initial_stack on 64-bitBrian Gerst
In order to facilitate parallel startup, start to eliminate some of the global variables passing information to CPUs in the startup path. However, start by introducing one more: smpboot_control. For now this merely holds the CPU# of the CPU which is coming up. Each CPU can then find its own per-cpu data, and everything else it needs can be found from there, allowing the other global variables to be removed. First to be removed is initial_stack. Each CPU can load %rsp from its current_task->thread.sp instead. That is already set up with the correct idle thread for APs. Set up the .sp field in INIT_THREAD on x86 so that the BSP also finds a suitable stack pointer in the static per-cpu data when coming up on first boot. On resume from S3, the CPU needs a temporary stack because its idle task is already active. Instead of setting initial_stack, the sleep code can simply set its own current->thread.sp to point to the temporary stack. Nobody else cares about ->thread.sp for a thread which is currently on a CPU, because the true value is actually in the %rsp register. Which is restored with the rest of the CPU context in do_suspend_lowlevel(). Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Usama Arif <usama.arif@bytedance.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Usama Arif <usama.arif@bytedance.com> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Link: https://lore.kernel.org/r/20230316222109.1940300-7-usama.arif@bytedance.com
2023-02-20Merge tag 'x86-boot-2023-02-20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: - Robustify/fix calling startup_{32,64}() from the decompressor code, and removing x86 quirk from scripts/head-object-list.txt as a result. - Do not register processors that cannot be onlined for x2APIC * tag 'x86-boot-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/acpi/boot: Do not register processors that cannot be onlined for x2APIC scripts/head-object-list: Remove x86 from the list x86/boot: Robustify calling startup_{32,64}() from the decompressor code
2023-01-26x86/ACPI/boot: Use try_cmpxchg() in __acpi_{acquire,release}_global_lock()Uros Bizjak
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in __acpi_{acquire,release}_global_lock(). x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after CMPXCHG (and related MOV instruction in front of CMPXCHG). Also, try_cmpxchg() implicitly assigns old *ptr value to "old" when CMPXCHG fails. There is no need to re-read the value in the loop. Note that the value from *ptr should be read using READ_ONCE() to prevent the compiler from merging, refetching or reordering the read. No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/20230116162522.4072-1-ubizjak@gmail.com
2023-01-10x86/acpi/boot: Do not register processors that cannot be onlined for x2APICKishon Vijay Abraham I
Section 5.2.12.12 Processor Local x2APIC Structure in the ACPI v6.5 spec mandates that both "enabled" and "online capable" Local APIC Flags should be used to determine if the processor is usable or not. However, Linux doesn't use the "online capable" flag for x2APIC to determine if the processor is usable. As a result, cpu_possible_mask has incorrect value and results in more memory getting allocated for per_cpu variables than it is going to be used. Make sure Linux parses both "enabled" and "online capable" flags for x2APIC to correctly determine if the processor is usable. Fixes: aa06e20f1be6 ("x86/ACPI: Don't add CPUs that are not online capable") Reported-by: Leo Duran <leo.duran@amd.com> Signed-off-by: Kishon Vijay Abraham I <kvijayab@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/r/20230105041059.39366-1-kvijayab@amd.com
2022-11-11x86/acpi/cstate: Optimize ARB_DISABLE on Centaur CPUsTony W Wang-oc
On all recent Centaur platforms, ARB_DISABLE is handled by PMU automatically while entering C3 type state. No need for OS to issue the ARB_DISABLE, so set bm_control to zero to indicate that. Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/all/1667792089-4904-1-git-send-email-TonyWWang-oc%40zhaoxin.com
2022-07-13ACPI: CPPC: Fix enabling CPPC on AMD systems with shared memoryMario Limonciello
When commit 72f2ecb7ece7 ("ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported") was introduced, we found collateral damage that a number of AMD systems that supported CPPC but didn't advertise support in _OSC stopped having a functional amd-pstate driver. The _OSC was only enforced on Intel systems at that time. This was fixed for the MSR based designs by commit 8b356e536e69f ("ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supported") but some shared memory based designs also support CPPC but haven't advertised support in the _OSC. Add support for those designs as well by hardcoding the list of systems. Fixes: 72f2ecb7ece7 ("ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported") Fixes: 8b356e536e69f ("ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supported") Link: https://lore.kernel.org/all/3559249.JlDtxWtqDm@natalenko.name/ Cc: 5.18+ <stable@vger.kernel.org> # 5.18+ Reported-and-tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-07-05ACPI: CPPC: Don't require _OSC if X86_FEATURE_CPPC is supportedMario Limonciello
commit 72f2ecb7ece7 ("ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported") added support for claiming to support CPPC in _OSC on non-Intel platforms. This unfortunately caused a regression on a vartiety of AMD platforms in the field because a number of AMD platforms don't set the `_OSC` bit 5 or 6 to indicate CPPC or CPPC v2 support. As these AMD platforms already claim CPPC support via a dedicated MSR from `X86_FEATURE_CPPC`, use this enable this feature rather than requiring the `_OSC` on platforms with a dedicated MSR. If there is additional breakage on the shared memory designs also missing this _OSC, additional follow up changes may be needed. Fixes: 72f2ecb7ece7 ("Set CPPC _OSC bits for all and when CPPC_LIB is supported") Reported-by: Perry Yuan <perry.yuan@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-24Merge tag 'pm-5.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These add support for 'artificial' Energy Models in which power numbers for different entities may be in different scales, add support for some new hardware, fix bugs and clean up code in multiple places. Specifics: - Update the Energy Model support code to allow the Energy Model to be artificial, which means that the power values may not be on a uniform scale with other devices providing power information, and update the cpufreq_cooling and devfreq_cooling thermal drivers to support artificial Energy Models (Lukasz Luba). - Make DTPM check the Energy Model type (Lukasz Luba). - Fix policy counter decrementation in cpufreq if Energy Model is in use (Pierre Gondois). - Add CPU-based scaling support to passive devfreq governor (Saravana Kannan, Chanwoo Choi). - Update the rk3399_dmc devfreq driver (Brian Norris). - Export dev_pm_ops instead of suspend() and resume() in the IIO chemical scd30 driver (Jonathan Cameron). - Add namespace variants of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and PM-runtime counterparts (Jonathan Cameron). - Move symbol exports in the IIO chemical scd30 driver into the IIO_SCD30 namespace (Jonathan Cameron). - Avoid device PM-runtime usage count underflows (Rafael Wysocki). - Allow dynamic debug to control printing of PM messages (David Cohen). - Fix some kernel-doc comments in hibernation code (Yang Li, Haowen Bai). - Preserve ACPI-table override during hibernation (Amadeusz Sławiński). - Improve support for suspend-to-RAM for PSCI OSI mode (Ulf Hansson). - Make Intel RAPL power capping driver support the RaptorLake and AlderLake N processors (Zhang Rui, Sumeet Pawnikar). - Remove redundant store to value after multiply in the RAPL power capping driver (Colin Ian King). - Add AlderLake processor support to the intel_idle driver (Zhang Rui). - Fix regression leading to no genpd governor in the PSCI cpuidle driver and fix the riscv-sbi cpuidle driver to allow a genpd governor to be used (Ulf Hansson). - Fix cpufreq governor clean up code to avoid using kfree() directly to free kobject-based items (Kevin Hao). - Prepare cpufreq for powerpc's asm/prom.h cleanup (Christophe Leroy). - Make intel_pstate notify frequency invariance code when no_turbo is turned on and off (Chen Yu). - Add Sapphire Rapids OOB mode support to intel_pstate (Srinivas Pandruvada). - Make cpufreq avoid unnecessary frequency updates due to mismatch between hardware and the frequency table (Viresh Kumar). - Make remove_cpu_dev_symlink() clear the real_cpus mask to simplify code (Viresh Kumar). - Rearrange cpufreq_offline() and cpufreq_remove_dev() to make the calling convention for some driver callbacks consistent (Rafael Wysocki). - Avoid accessing half-initialized cpufreq policies from the show() and store() sysfs functions (Schspa Shi). - Rearrange cpufreq_offline() to make the calling convention for some driver callbacks consistent (Schspa Shi). - Update CPPC handling in cpufreq (Pierre Gondois). - Extend dev_pm_domain_detach() doc (Krzysztof Kozlowski). - Move genpd's time-accounting to ktime_get_mono_fast_ns() (Ulf Hansson). - Improve the way genpd deals with its governors (Ulf Hansson). - Update the turbostat utility to version 2022.04.16 (Len Brown, Dan Merillat, Sumeet Pawnikar, Zephaniah E. Loss-Cutler-Hull, Chen Yu)" * tag 'pm-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (94 commits) PM: domains: Trust domain-idle-states from DT to be correct by genpd PM: domains: Measure power-on/off latencies in genpd based on a governor PM: domains: Allocate governor data dynamically based on a genpd governor PM: domains: Clean up some code in pm_genpd_init() and genpd_remove() PM: domains: Fix initialization of genpd's next_wakeup PM: domains: Fixup QoS latency measurements for IRQ safe devices in genpd PM: domains: Measure suspend/resume latencies in genpd based on governor PM: domains: Move the next_wakeup variable into the struct gpd_timing_data PM: domains: Allocate gpd_timing_data dynamically based on governor PM: domains: Skip another warning in irq_safe_dev_in_sleep_domain() PM: domains: Rename irq_safe_dev_in_no_sleep_domain() in genpd PM: domains: Don't check PM_QOS_FLAG_NO_POWER_OFF in genpd PM: domains: Drop redundant code for genpd always-on governor PM: domains: Add GENPD_FLAG_RPM_ALWAYS_ON for the always-on governor powercap: intel_rapl: remove redundant store to value after multiply cpufreq: CPPC: Enable dvfs_possible_from_any_cpu cpufreq: CPPC: Enable fast_switch ACPI: CPPC: Assume no transition latency if no PCCT ACPI: bus: Set CPPC _OSC bits for all and when CPPC_LIB is supported ACPI: CPPC: Check _OSC for flexible address space ...
2022-05-24Merge tag 'acpi-5.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These update the ACPICA kernel code to upstream revision 20220331, improve handling of PCI devices that are in D3cold during system initialization, add support for a few features, fix bugs and clean up code. Specifics: - Update ACPICA code in the kernel to upstream revision 20220331 including the following changes: - Add support for the Windows 11 _OSI string (Mario Limonciello) - Add the CFMWS subtable to the CEDT table (Lawrence Hileman). - iASL: NHLT: Treat Terminator as specific_config (Piotr Maziarz). - iASL: NHLT: Fix parsing undocumented bytes at the end of Endpoint Descriptor (Piotr Maziarz). - iASL: NHLT: Rename linux specific strucures to device_info (Piotr Maziarz). - Add new ACPI 6.4 semantics to Load() and LoadTable() (Bob Moore). - Clean up double word in comment (Tom Rix). - Update copyright notices to the year 2022 (Bob Moore). - Remove some tabs and // comments - automated cleanup (Bob Moore). - Replace zero-length array with flexible-array member (Gustavo A. R. Silva). - Interpreter: Add units to time variable names (Paul Menzel). - Add support for ARM Performance Monitoring Unit Table (Besar Wicaksono). - Inform users about ACPI spec violation related to sleep length (Paul Menzel). - iASL/MADT: Add OEM-defined subtable (Bob Moore). - Interpreter: Fix some typo mistakes (Selvarasu Ganesan). - Updates for revision E.d of IORT (Shameer Kolothum). - Use ACPI_FORMAT_UINT64 for 64-bit output (Bob Moore). - Improve debug messages in the ACPI device PM code (Rafael Wysocki). - Block ASUS B1400CEAE from suspend to idle by default (Mario Limonciello). - Improve handling of PCI devices that are in D3cold during system initialization (Rafael Wysocki). - Fix BERT error region memory mapping (Lorenzo Pieralisi). - Add support for NVIDIA 16550-compatible port subtype to the SPCR parsing code (Jeff Brasen). - Use static for BGRT_SHOW kobj_attribute defines (Tom Rix). - Fix missing prototype warning for acpi_agdi_init() (Ilkka Koskinen). - Fix missing ERST record ID in the APEI code (Liu Xinpeng). - Make APEI error injection to refuse to inject into the zero page (Tony Luck). - Correct description of INT3407 / INT3532 DPTF attributes in sysfs (Sumeet Pawnikar). - Add support for high frequency impedance notification to the DPTF driver (Sumeet Pawnikar). - Make mp_config_acpi_gsi() a void function (Li kunyu). - Unify Package () representation for properties in the ACPI device properties documentation (Andy Shevchenko). - Include UUID in _DSM evaluation warning (Michael Niewöhner)" * tag 'acpi-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (41 commits) Revert "ACPICA: executer/exsystem: Warn about sleeps greater than 10 ms" ACPI: utils: include UUID in _DSM evaluation warning ACPI: PM: Block ASUS B1400CEAE from suspend to idle by default x86: ACPI: Make mp_config_acpi_gsi() a void function ACPI: DPTF: Add support for high frequency impedance notification ACPI: AGDI: Fix missing prototype warning for acpi_agdi_init() ACPI: bus: Avoid non-ACPI device objects in walks over children ACPI: DPTF: Correct description of INT3407 / INT3532 attributes ACPI: BGRT: use static for BGRT_SHOW kobj_attribute defines ACPI, APEI, EINJ: Refuse to inject into the zero page ACPI: PM: Always print final debug message in acpi_device_set_power() ACPI: SPCR: Add support for NVIDIA 16550-compatible port subtype ACPI: docs: enumeration: Unify Package () for properties (part 2) ACPI: APEI: Fix missing ERST record id ACPICA: Update version to 20220331 ACPICA: exsystem.c: Use ACPI_FORMAT_UINT64 for 64-bit output ACPICA: IORT: Updates for revision E.d ACPICA: executer/exsystem: Fix some typo mistakes ACPICA: iASL/MADT: Add OEM-defined subtable ACPICA: executer/exsystem: Warn about sleeps greater than 10 ms ...
2022-05-23Merge tag 'x86_cleanups_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: - Serious sanitization and cleanup of the whole APERF/MPERF and frequency invariance code along with removing the need for unnecessary IPIs - Finally remove a.out support - The usual trivial cleanups and fixes all over x86 * tag 'x86_cleanups_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86: Remove empty files x86/speculation: Add missing srbds=off to the mitigations= help text x86/prctl: Remove pointless task argument x86/aperfperf: Make it correct on 32bit and UP kernels x86/aperfmperf: Integrate the fallback code from show_cpuinfo() x86/aperfmperf: Replace arch_freq_get_on_cpu() x86/aperfmperf: Replace aperfmperf_get_khz() x86/aperfmperf: Store aperf/mperf data for cpu frequency reads x86/aperfmperf: Make parts of the frequency invariance code unconditional x86/aperfmperf: Restructure arch_scale_freq_tick() x86/aperfmperf: Put frequency invariance aperf/mperf data into a struct x86/aperfmperf: Untangle Intel and AMD frequency invariance init x86/aperfmperf: Separate AP/BP frequency invariance init x86/smp: Move APERF/MPERF code where it belongs x86/aperfmperf: Dont wake idle CPUs in arch_freq_get_on_cpu() x86/process: Fix kernel-doc warning due to a changed function name x86: Remove a.out support x86/mm: Replace nodes_weight() with nodes_empty() where appropriate x86: Replace cpumask_weight() with cpumask_empty() where appropriate x86/pkeys: Remove __arch_set_user_pkey_access() declaration ...
2022-05-11x86: ACPI: Make mp_config_acpi_gsi() a void functionLi kunyu
Because the return value of mp_config_acpi_gsi() is not use, change it into a void function. Signed-off-by: Li kunyu <kunyu@nfschina.com> [ rjw: Subject and changelog rewrite ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-27x86/aperfmperf: Untangle Intel and AMD frequency invariance initThomas Gleixner
AMD boot CPU initialization happens late via ACPI/CPPC which prevents the Intel parts from being marked __init. Split out the common code and provide a dedicated interface for the AMD initialization and mark the Intel specific code and data __init. The remaining text size is almost cut in half: text: 2614 -> 1350 init.text: 0 -> 786 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20220415161206.592465719@linutronix.de
2022-04-27x86/aperfmperf: Separate AP/BP frequency invariance initThomas Gleixner
This code is convoluted and because it can be invoked post init via the ACPI/CPPC code, all of the initialization functionality is built in instead of being part of init text and init data. As a first step create separate calls for the boot and the application processors. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@kernel.org> Link: https://lore.kernel.org/r/20220415161206.536733494@linutronix.de
2022-04-13x86/ACPI: Preserve ACPI-table override during hibernationAmadeusz Sławiński
When overriding NHLT ACPI-table tests show that on some platforms there is problem that NHLT contains garbage after hibernation/resume cycle. Problem stems from the fact that ACPI override performs early memory allocation using memblock_phys_alloc_range() in memblock_phys_alloc_range(). This memory block is later being marked as ACPI memory block in arch_reserve_mem_area(). Later when memory areas are considered for hibernation it is being marked as nosave in e820__register_nosave_regions(). Fix this by marking ACPI override memory area as ACPI NVS (Non-Volatile-Sleeping), which according to specification needs to be saved on entering S4 and restored when leaving and is implemented as such in kernel. Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-04-07x86/acpi/x86/boot: Add multiprocessor wake-up supportKuppuswamy Sathyanarayanan
Secondary CPU startup is currently performed with something called the "INIT/SIPI protocol". This protocol requires assistance from VMMs to boot guests. As should be a familiar story by now, that support can not be provded to TDX guests because TDX VMMs are not trusted by guests. To remedy this situation a new[1] "Multiprocessor Wakeup Structure" has been added to to an existing ACPI table (MADT). This structure provides the physical address of a "mailbox". A write to the mailbox then steers the secondary CPU to the boot code. Add ACPI MADT wake structure parsing support and wake support. Use this support to wake CPUs whenever it is present instead of INIT/SIPI. While this structure can theoretically be used on 32-bit kernels, there are no 32-bit TDX guest kernels. It has not been tested and can not practically *be* tested on 32-bit. Make it 64-bit only. 1. Details about the new structure can be found in ACPI v6.4, in the "Multiprocessor Wakeup Structure" section. Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20220405232939.73860-22-kirill.shutemov@linux.intel.com