Commit Graph

19331 Commits

Author SHA1 Message Date
Linus Torvalds
d8941ce52b - Constify yet another static struct bus_type instance now that the
driver core can handle that
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Merge tag 'ras_core_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS fixlet from Borislav Petkov:

 - Constify yet another static struct bus_type instance now that the
   driver core can handle that

* tag 'ras_core_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Make mce_subsys const
2024-03-11 17:22:57 -07:00
Linus Torvalds
720c857907 Support for x86 Fast Return and Event Delivery (FRED):
FRED is a replacement for IDT event delivery on x86 and addresses most of
 the technical nightmares which IDT exposes:
 
  1) Exception cause registers like CR2 need to be manually preserved in
     nested exception scenarios.
 
  2) Hardware interrupt stack switching is suboptimal for nested exceptions
     as the interrupt stack mechanism rewinds the stack on each entry which
     requires a massive effort in the low level entry of #NMI code to handle
     this.
 
  3) No hardware distinction between entry from kernel or from user which
     makes establishing kernel context more complex than it needs to be
     especially for unconditionally nestable exceptions like NMI.
 
  4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a
     problem when the perf NMI takes a fault when collecting a stack trace.
 
  5) Partial restore of ESP when returning to a 16-bit segment
 
  6) Limitation of the vector space which can cause vector exhaustion on
     large systems.
 
  7) Inability to differentiate NMI sources
 
 FRED addresses these shortcomings by:
 
  1) An extended exception stack frame which the CPU uses to save exception
     cause registers. This ensures that the meta information for each
     exception is preserved on stack and avoids the extra complexity of
     preserving it in software.
 
  2) Hardware interrupt stack switching is non-rewinding if a nested
     exception uses the currently interrupt stack.
 
  3) The entry points for kernel and user context are separate and GS BASE
     handling which is required to establish kernel context for per CPU
     variable access is done in hardware.
 
  4) NMIs are now nesting protected. They are only reenabled on the return
     from NMI.
 
  5) FRED guarantees full restore of ESP
 
  6) FRED does not put a limitation on the vector space by design because it
     uses a central entry points for kernel and user space and the CPUstores
     the entry type (exception, trap, interrupt, syscall) on the entry stack
     along with the vector number. The entry code has to demultiplex this
     information, but this removes the vector space restriction.
 
     The first hardware implementations will still have the current
     restricted vector space because lifting this limitation requires
     further changes to the local APIC.
 
  7) FRED stores the vector number and meta information on stack which
     allows having more than one NMI vector in future hardware when the
     required local APIC changes are in place.
 
 The series implements the initial FRED support by:
 
  - Reworking the existing entry and IDT handling infrastructure to
    accomodate for the alternative entry mechanism.
 
  - Expanding the stack frame to accomodate for the extra 16 bytes FRED
    requires to store context and meta information
 
  - Providing FRED specific C entry points for events which have information
    pushed to the extended stack frame, e.g. #PF and #DB.
 
  - Providing FRED specific C entry points for #NMI and #MCE
 
  - Implementing the FRED specific ASM entry points and the C code to
    demultiplex the events
 
  - Providing detection and initialization mechanisms and the necessary
    tweaks in context switching, GS BASE handling etc.
 
 The FRED integration aims for maximum code reuse vs. the existing IDT
 implementation to the extent possible and the deviation in hot paths like
 context switching are handled with alternatives to minimalize the
 impact. The low level entry and exit paths are seperate due to the extended
 stack frame and the hardware based GS BASE swichting and therefore have no
 impact on IDT based systems.
 
 It has been extensively tested on existing systems and on the FRED
 simulation and as of now there are know outstanding problems.
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Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 FRED support from Thomas Gleixner:
 "Support for x86 Fast Return and Event Delivery (FRED).

  FRED is a replacement for IDT event delivery on x86 and addresses most
  of the technical nightmares which IDT exposes:

   1) Exception cause registers like CR2 need to be manually preserved
      in nested exception scenarios.

   2) Hardware interrupt stack switching is suboptimal for nested
      exceptions as the interrupt stack mechanism rewinds the stack on
      each entry which requires a massive effort in the low level entry
      of #NMI code to handle this.

   3) No hardware distinction between entry from kernel or from user
      which makes establishing kernel context more complex than it needs
      to be especially for unconditionally nestable exceptions like NMI.

   4) NMI nesting caused by IRET unconditionally reenabling NMIs, which
      is a problem when the perf NMI takes a fault when collecting a
      stack trace.

   5) Partial restore of ESP when returning to a 16-bit segment

   6) Limitation of the vector space which can cause vector exhaustion
      on large systems.

   7) Inability to differentiate NMI sources

  FRED addresses these shortcomings by:

   1) An extended exception stack frame which the CPU uses to save
      exception cause registers. This ensures that the meta information
      for each exception is preserved on stack and avoids the extra
      complexity of preserving it in software.

   2) Hardware interrupt stack switching is non-rewinding if a nested
      exception uses the currently interrupt stack.

   3) The entry points for kernel and user context are separate and GS
      BASE handling which is required to establish kernel context for
      per CPU variable access is done in hardware.

   4) NMIs are now nesting protected. They are only reenabled on the
      return from NMI.

   5) FRED guarantees full restore of ESP

   6) FRED does not put a limitation on the vector space by design
      because it uses a central entry points for kernel and user space
      and the CPUstores the entry type (exception, trap, interrupt,
      syscall) on the entry stack along with the vector number. The
      entry code has to demultiplex this information, but this removes
      the vector space restriction.

      The first hardware implementations will still have the current
      restricted vector space because lifting this limitation requires
      further changes to the local APIC.

   7) FRED stores the vector number and meta information on stack which
      allows having more than one NMI vector in future hardware when the
      required local APIC changes are in place.

  The series implements the initial FRED support by:

   - Reworking the existing entry and IDT handling infrastructure to
     accomodate for the alternative entry mechanism.

   - Expanding the stack frame to accomodate for the extra 16 bytes FRED
     requires to store context and meta information

   - Providing FRED specific C entry points for events which have
     information pushed to the extended stack frame, e.g. #PF and #DB.

   - Providing FRED specific C entry points for #NMI and #MCE

   - Implementing the FRED specific ASM entry points and the C code to
     demultiplex the events

   - Providing detection and initialization mechanisms and the necessary
     tweaks in context switching, GS BASE handling etc.

  The FRED integration aims for maximum code reuse vs the existing IDT
  implementation to the extent possible and the deviation in hot paths
  like context switching are handled with alternatives to minimalize the
  impact. The low level entry and exit paths are seperate due to the
  extended stack frame and the hardware based GS BASE swichting and
  therefore have no impact on IDT based systems.

  It has been extensively tested on existing systems and on the FRED
  simulation and as of now there are no outstanding problems"

* tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/fred: Fix init_task thread stack pointer initialization
  MAINTAINERS: Add a maintainer entry for FRED
  x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly
  x86/fred: Invoke FRED initialization code to enable FRED
  x86/fred: Add FRED initialization functions
  x86/syscall: Split IDT syscall setup code into idt_syscall_init()
  KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling
  x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI
  x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code
  x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user
  x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled
  x86/traps: Add sysvec_install() to install a system interrupt handler
  x86/fred: FRED entry/exit and dispatch code
  x86/fred: Add a machine check entry stub for FRED
  x86/fred: Add a NMI entry stub for FRED
  x86/fred: Add a debug fault entry stub for FRED
  x86/idtentry: Incorporate definitions/declarations of the FRED entries
  x86/fred: Make exc_page_fault() work for FRED
  x86/fred: Allow single-step trap and NMI when starting a new task
  x86/fred: No ESPFIX needed when FRED is enabled
  ...
2024-03-11 16:00:17 -07:00
Linus Torvalds
ca7e917769 Rework of APIC enumeration and topology evaluation:
The current implementation has a couple of shortcomings:
 
   - It fails to handle hybrid systems correctly.
 
   - The APIC registration code which handles CPU number assignents is in
     the middle of the APIC code and detached from the topology evaluation.
 
   - The various mechanisms which enumerate APICs, ACPI, MPPARSE and guest
     specific ones, tweak global variables as they see fit or in case of
     XENPV just hack around the generic mechanisms completely.
 
   - The CPUID topology evaluation code is sprinkled all over the vendor
     code and reevaluates global variables on every hotplug operation.
 
   - There is no way to analyze topology on the boot CPU before bringing up
     the APs. This causes problems for infrastructure like PERF which needs
     to size certain aspects upfront or could be simplified if that would be
     possible.
 
   - The APIC admission and CPU number association logic is incomprehensible
     and overly complex and needs to be kept around after boot instead of
     completing this right after the APIC enumeration.
 
 This update addresses these shortcomings with the following changes:
 
   - Rework the CPUID evaluation code so it is common for all vendors and
     provides information about the APIC ID segments in a uniform way
     independent of the number of segments (Thread, Core, Module, ..., Die,
     Package) so that this information can be computed instead of rewriting
     global variables of dubious value over and over.
 
   - A few cleanups and simplifcations of the APIC, IO/APIC and related
     interfaces to prepare for the topology evaluation changes.
 
   - Seperation of the parser stages so the early evaluation which tries to
     find the APIC address can be seperately overridden from the late
     evaluation which enumerates and registers the local APIC as further
     preparation for sanitizing the topology evaluation.
 
   - A new registration and admission logic which
 
      - encapsulates the inner workings so that parsers and guest logic
        cannot longer fiddle in it
 
      - uses the APIC ID segments to build topology bitmaps at registration
        time
 
      - provides a sane admission logic
 
      - allows to detect the crash kernel case, where CPU0 does not run on
        the real BSP, automatically. This is required to prevent sending
        INIT/SIPI sequences to the real BSP which would reset the whole
        machine. This was so far handled by a tedious command line
        parameter, which does not even work in nested crash scenarios.
 
      - Associates CPU number after the enumeration completed and prevents
        the late registration of APICs, which was somehow tolerated before.
 
   - Converting all parsers and guest enumeration mechanisms over to the
     new interfaces.
 
     This allows to get rid of all global variable tweaking from the parsers
     and enumeration mechanisms and sanitizes the XEN[PV] handling so it can
     use CPUID evaluation for the first time.
 
   - Mopping up existing sins by taking the information from the APIC ID
     segment bitmaps.
 
     This evaluates hybrid systems correctly on the boot CPU and allows for
     cleanups and fixes in the related drivers, e.g. PERF.
 
 The series has been extensively tested and the minimal late fallout due to
 a broken ACPI/MADT table has been addressed by tightening the admission
 logic further.
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Merge tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 APIC updates from Thomas Gleixner:
 "Rework of APIC enumeration and topology evaluation.

  The current implementation has a couple of shortcomings:

   - It fails to handle hybrid systems correctly.

   - The APIC registration code which handles CPU number assignents is
     in the middle of the APIC code and detached from the topology
     evaluation.

   - The various mechanisms which enumerate APICs, ACPI, MPPARSE and
     guest specific ones, tweak global variables as they see fit or in
     case of XENPV just hack around the generic mechanisms completely.

   - The CPUID topology evaluation code is sprinkled all over the vendor
     code and reevaluates global variables on every hotplug operation.

   - There is no way to analyze topology on the boot CPU before bringing
     up the APs. This causes problems for infrastructure like PERF which
     needs to size certain aspects upfront or could be simplified if
     that would be possible.

   - The APIC admission and CPU number association logic is
     incomprehensible and overly complex and needs to be kept around
     after boot instead of completing this right after the APIC
     enumeration.

  This update addresses these shortcomings with the following changes:

   - Rework the CPUID evaluation code so it is common for all vendors
     and provides information about the APIC ID segments in a uniform
     way independent of the number of segments (Thread, Core, Module,
     ..., Die, Package) so that this information can be computed instead
     of rewriting global variables of dubious value over and over.

   - A few cleanups and simplifcations of the APIC, IO/APIC and related
     interfaces to prepare for the topology evaluation changes.

   - Seperation of the parser stages so the early evaluation which tries
     to find the APIC address can be seperately overridden from the late
     evaluation which enumerates and registers the local APIC as further
     preparation for sanitizing the topology evaluation.

   - A new registration and admission logic which

       - encapsulates the inner workings so that parsers and guest logic
         cannot longer fiddle in it

       - uses the APIC ID segments to build topology bitmaps at
         registration time

       - provides a sane admission logic

       - allows to detect the crash kernel case, where CPU0 does not run
         on the real BSP, automatically. This is required to prevent
         sending INIT/SIPI sequences to the real BSP which would reset
         the whole machine. This was so far handled by a tedious command
         line parameter, which does not even work in nested crash
         scenarios.

       - Associates CPU number after the enumeration completed and
         prevents the late registration of APICs, which was somehow
         tolerated before.

   - Converting all parsers and guest enumeration mechanisms over to the
     new interfaces.

     This allows to get rid of all global variable tweaking from the
     parsers and enumeration mechanisms and sanitizes the XEN[PV]
     handling so it can use CPUID evaluation for the first time.

   - Mopping up existing sins by taking the information from the APIC ID
     segment bitmaps.

     This evaluates hybrid systems correctly on the boot CPU and allows
     for cleanups and fixes in the related drivers, e.g. PERF.

  The series has been extensively tested and the minimal late fallout
  due to a broken ACPI/MADT table has been addressed by tightening the
  admission logic further"

* tag 'x86-apic-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
  x86/topology: Ignore non-present APIC IDs in a present package
  x86/apic: Build the x86 topology enumeration functions on UP APIC builds too
  smp: Provide 'setup_max_cpus' definition on UP too
  smp: Avoid 'setup_max_cpus' namespace collision/shadowing
  x86/bugs: Use fixed addressing for VERW operand
  x86/cpu/topology: Get rid of cpuinfo::x86_max_cores
  x86/cpu/topology: Provide __num_[cores|threads]_per_package
  x86/cpu/topology: Rename topology_max_die_per_package()
  x86/cpu/topology: Rename smp_num_siblings
  x86/cpu/topology: Retrieve cores per package from topology bitmaps
  x86/cpu/topology: Use topology logical mapping mechanism
  x86/cpu/topology: Provide logical pkg/die mapping
  x86/cpu/topology: Simplify cpu_mark_primary_thread()
  x86/cpu/topology: Mop up primary thread mask handling
  x86/cpu/topology: Use topology bitmaps for sizing
  x86/cpu/topology: Let XEN/PV use topology from CPUID/MADT
  x86/xen/smp_pv: Count number of vCPUs early
  x86/cpu/topology: Assign hotpluggable CPUIDs during init
  x86/cpu/topology: Reject unknown APIC IDs on ACPI hotplug
  x86/topology: Add a mechanism to track topology via APIC IDs
  ...
2024-03-11 15:45:55 -07:00
Linus Torvalds
80a76c60e5 Updates for timekeeping and PTP core:
The cross-timestamp mechanism which allows to correlate hardware
   clocks uses clocksource pointers for describing the correlation.
 
   That's suboptimal as drivers need to obtain the pointer, which requires
   needless exports and exposing internals.
 
   This can be completely avoided by assigning clocksource IDs and using
   them for describing the correlated clock source.
 
   This update adds clocksource IDs to all clocksources in the tree which
   can be exposed to this mechanism and removes the pointer and now needless
   exports.
 
   This is separate from the timer core changes as it was provided to the
   PTP folks to build further changes on top.
 
   A related improvement for the core and the correlation handling has not
   made it this time, but is expected to get ready for the next round.
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Merge tag 'timers-ptp-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull clocksource updates from Thomas Gleixner:
 "Updates for timekeeping and PTP core.

  The cross-timestamp mechanism which allows to correlate hardware
  clocks uses clocksource pointers for describing the correlation.

  That's suboptimal as drivers need to obtain the pointer, which
  requires needless exports and exposing internals. This can all be
  completely avoided by assigning clocksource IDs and using them for
  describing the correlated clock source.

  So this adds clocksource IDs to all clocksources in the tree which can
  be exposed to this mechanism and removes the pointer and now needless
  exports.

  A related improvement for the core and the correlation handling has
  not made it this time, but is expected to get ready for the next
  round"

* tag 'timers-ptp-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kvmclock: Unexport kvmclock clocksource
  treewide: Remove system_counterval_t.cs, which is never read
  timekeeping: Evaluate system_counterval_t.cs_id instead of .cs
  ptp/kvm, arm_arch_timer: Set system_counterval_t.cs_id to constant
  x86/kvm, ptp/kvm: Add clocksource ID, set system_counterval_t.cs_id
  x86/tsc: Add clocksource ID, set system_counterval_t.cs_id
  timekeeping: Add clocksource ID to struct system_counterval_t
  x86/tsc: Correct kernel-doc notation
2024-03-11 14:25:18 -07:00
Linus Torvalds
4527e83780 Updates for the MSI interrupt subsystem and RISC-V initial MSI support:
- Core and platform-MSI
 
     The core changes have been adopted from previous work which converted
     ARM[64] to the new per device MSI domain model, which was merged to
     support multiple MSI domain per device. The ARM[64] changes are being
     worked on too, but have not been ready yet. The core and platform-MSI
     changes have been split out to not hold up RISC-V and to avoid that
     RISC-V builds on the scheduled for removal interfaces.
 
     The core support provides new interfaces to handle wire to MSI bridges
     in a straight forward way and introduces new platform-MSI interfaces
     which are built on top of the per device MSI domain model.
 
     Once ARM[64] is converted over the old platform-MSI interfaces and the
     related ugliness in the MSI core code will be removed.
 
   - Drivers:
 
     - Add a new driver for the Andes hart-level interrupt controller
 
     - Rework the SiFive PLIC driver to prepare for MSI suport
 
     - Expand the RISC-V INTC driver to support the new RISC-V AIA
       controller which provides the basis for MSI on RISC-V
 
     - A few fixup for the fallout of the core changes.
 
     The actual MSI parts for RISC-V were finalized late and have been
     post-poned for the next merge window.
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Merge tag 'irq-msi-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull MSI updates from Thomas Gleixner:
 "Updates for the MSI interrupt subsystem and initial RISC-V MSI
  support.

  The core changes have been adopted from previous work which converted
  ARM[64] to the new per device MSI domain model, which was merged to
  support multiple MSI domain per device. The ARM[64] changes are being
  worked on too, but have not been ready yet. The core and platform-MSI
  changes have been split out to not hold up RISC-V and to avoid that
  RISC-V builds on the scheduled for removal interfaces.

  The core support provides new interfaces to handle wire to MSI bridges
  in a straight forward way and introduces new platform-MSI interfaces
  which are built on top of the per device MSI domain model.

  Once ARM[64] is converted over the old platform-MSI interfaces and the
  related ugliness in the MSI core code will be removed.

  The actual MSI parts for RISC-V were finalized late and have been
  post-poned for the next merge window.

  Drivers:

   - Add a new driver for the Andes hart-level interrupt controller

   - Rework the SiFive PLIC driver to prepare for MSI suport

   - Expand the RISC-V INTC driver to support the new RISC-V AIA
     controller which provides the basis for MSI on RISC-V

   - A few fixup for the fallout of the core changes"

* tag 'irq-msi-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  irqchip/riscv-intc: Fix low-level interrupt handler setup for AIA
  x86/apic/msi: Use DOMAIN_BUS_GENERIC_MSI for HPET/IO-APIC domain search
  genirq/matrix: Dynamic bitmap allocation
  irqchip/riscv-intc: Add support for RISC-V AIA
  irqchip/sifive-plic: Improve locking safety by using irqsave/irqrestore
  irqchip/sifive-plic: Parse number of interrupts and contexts early in plic_probe()
  irqchip/sifive-plic: Cleanup PLIC contexts upon irqdomain creation failure
  irqchip/sifive-plic: Use riscv_get_intc_hwnode() to get parent fwnode
  irqchip/sifive-plic: Use devm_xyz() for managed allocation
  irqchip/sifive-plic: Use dev_xyz() in-place of pr_xyz()
  irqchip/sifive-plic: Convert PLIC driver into a platform driver
  irqchip/riscv-intc: Introduce Andes hart-level interrupt controller
  irqchip/riscv-intc: Allow large non-standard interrupt number
  genirq/irqdomain: Don't call ops->select for DOMAIN_BUS_ANY tokens
  irqchip/imx-intmux: Handle pure domain searches correctly
  genirq/msi: Provide MSI_FLAG_PARENT_PM_DEV
  genirq/irqdomain: Reroute device MSI create_mapping
  genirq/msi: Provide allocation/free functions for "wired" MSI interrupts
  genirq/msi: Optionally use dev->fwnode for device domain
  genirq/msi: Provide DOMAIN_BUS_WIRED_TO_MSI
  ...
2024-03-11 14:03:03 -07:00
Xin Li (Intel)
c416b5bac6 x86/fred: Fix init_task thread stack pointer initialization
As TOP_OF_KERNEL_STACK_PADDING was defined as 0 on x86_64, it went
unnoticed that the initialization of the .sp field in INIT_THREAD and some
calculations in the low level startup code do not take the padding into
account.

FRED enabled kernels require a 16 byte padding, which means that the init
task initialization and the low level startup code use the wrong stack
offset.

Subtract TOP_OF_KERNEL_STACK_PADDING in all affected places to adjust for
this.

Fixes: 65c9cc9e2c ("x86/fred: Reserve space for the FRED stack frame")
Fixes: 3adee777ad ("x86/smpboot: Remove initial_stack on 64-bit")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Closes: https://lore.kernel.org/oe-lkp/202402262159.183c2a37-lkp@intel.com
Link: https://lore.kernel.org/r/20240304083333.449322-1-xin@zytor.com
2024-03-07 11:55:36 +01:00
Thomas Gleixner
f0551af021 x86/topology: Ignore non-present APIC IDs in a present package
Borislav reported that one of his systems has a broken MADT table which
advertises eight present APICs and 24 non-present APICs in the same
package.

The non-present ones are considered hot-pluggable by the topology
evaluation code, which is obviously bogus as there is no way to hot-plug
within the same package.

As the topology evaluation code accounts for hot-pluggable CPUs in a
package, the maximum number of cores per package is computed wrong, which
in turn causes the uncore performance counter driver to access non-existing
MSRs. It will probably confuse other entities which rely on the maximum
number of cores and threads per package too.

Cure this by ignoring hot-pluggable APIC IDs within a present package.

In theory it would be reasonable to just do this unconditionally, but then
there is this thing called reality^Wvirtualization which ruins
everything. Virtualization is the only existing user of "physical" hotplug
and the virtualization tools allow the above scenario. Whether that is
actually in use or not is unknown.

As it can be argued that the virtualization case is not affected by the
issues which exposed the reported problem, allow the bogosity if the kernel
determined that it is running in a VM for now.

Fixes: 89b0f15f40 ("x86/cpu/topology: Get rid of cpuinfo::x86_max_cores")
Reported-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/87a5nbvccx.ffs@tglx
2024-03-06 14:35:30 +01:00
Jiri Bohac
7fd817c906 x86/e820: Don't reserve SETUP_RNG_SEED in e820
SETUP_RNG_SEED in setup_data is supplied by kexec and should
not be reserved in the e820 map.

Doing so reserves 16 bytes of RAM when booting with kexec.
(16 bytes because data->len is zeroed by parse_setup_data so only
sizeof(setup_data) is reserved.)

When kexec is used repeatedly, each boot adds two entries in the
kexec-provided e820 map as the 16-byte range splits a larger
range of usable memory. Eventually all of the 128 available entries
get used up. The next split will result in losing usable memory
as the new entries cannot be added to the e820 map.

Fixes: 68b8e9713c ("x86/setup: Use rng seeds from setup_data")
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/ZbmOjKnARGiaYBd5@dwarf.suse.cz
2024-03-01 10:27:20 -08:00
Ingo Molnar
9b9c280b9a Merge branch 'x86/urgent' into x86/apic, to resolve conflicts
Conflicts:
	arch/x86/kernel/cpu/common.c
	arch/x86/kernel/cpu/intel.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-02-27 10:09:49 +01:00
Ingo Molnar
6be4ec2968 x86/apic: Build the x86 topology enumeration functions on UP APIC builds too
These functions are mostly pointless on UP, but nevertheless the
64-bit UP APIC build already depends on the existence of
topology_apply_cmdline_limits_early(), which caused a build bug,
resolve it by making them available under CONFIG_X86_LOCAL_APIC,
as their prototypes already are.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2024-02-27 10:05:41 +01:00
Paolo Bonzini
6890cb1ace x86/cpu/intel: Detect TME keyid bits before setting MTRR mask registers
MKTME repurposes the high bit of physical address to key id for encryption
key and, even though MAXPHYADDR in CPUID[0x80000008] remains the same,
the valid bits in the MTRR mask register are based on the reduced number
of physical address bits.

detect_tme() in arch/x86/kernel/cpu/intel.c detects TME and subtracts
it from the total usable physical bits, but it is called too late.
Move the call to early_init_intel() so that it is called in setup_arch(),
before MTRRs are setup.

This fixes boot on TDX-enabled systems, which until now only worked with
"disable_mtrr_cleanup".  Without the patch, the values written to the
MTRRs mask registers were 52-bit wide (e.g. 0x000fffff_80000800) and
the writes failed; with the patch, the values are 46-bit wide, which
matches the reduced MAXPHYADDR that is shown in /proc/cpuinfo.

Reported-by: Zixi Chen <zixchen@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240131230902.1867092-3-pbonzini%40redhat.com
2024-02-26 08:16:16 -08:00
Paolo Bonzini
9a458198eb x86/cpu: Allow reducing x86_phys_bits during early_identify_cpu()
In commit fbf6449f84 ("x86/sev-es: Set x86_virt_bits to the correct
value straight away, instead of a two-phase approach"), the initialization
of c->x86_phys_bits was moved after this_cpu->c_early_init(c).  This is
incorrect because early_init_amd() expected to be able to reduce the
value according to the contents of CPUID leaf 0x8000001f.

Fortunately, the bug was negated by init_amd()'s call to early_init_amd(),
which does reduce x86_phys_bits in the end.  However, this is very
late in the boot process and, most notably, the wrong value is used for
x86_phys_bits when setting up MTRRs.

To fix this, call get_cpu_address_sizes() as soon as X86_FEATURE_CPUID is
set/cleared, and c->extended_cpuid_level is retrieved.

Fixes: fbf6449f84 ("x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc:stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240131230902.1867092-2-pbonzini%40redhat.com
2024-02-26 08:16:15 -08:00
Thomas Gleixner
c147e1ef59 x86/apic/msi: Use DOMAIN_BUS_GENERIC_MSI for HPET/IO-APIC domain search
The recent restriction to invoke irqdomain_ops::select() only when the
domain bus token is not DOMAIN_BUS_ANY breaks the search for the parent MSI
domain of HPET and IO-APIC. The latter causes a full boot fail.

The restriction itself makes sense to avoid adding DOMAIN_BUS_ANY matches
into the various ARM specific select() callbacks. Reverting this change
would obviously break ARM platforms again and require DOMAIN_BUS_ANY
matches added to various places.

A simpler solution is to use the DOMAIN_BUS_GENERIC_MSI token for the HPET
and IO-APIC parent domain search. This works out of the box because the
affected parent domains check only for the firmware specification content
and not for the bus token.

Fixes: 5aa3c0cf5b ("genirq/irqdomain: Don't call ops->select for DOMAIN_BUS_ANY tokens")
Reported-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/878r38cy8n.ffs@tglx
2024-02-25 18:53:08 +01:00
Pawan Gupta
6613d82e61 x86/bugs: Use ALTERNATIVE() instead of mds_user_clear static key
The VERW mitigation at exit-to-user is enabled via a static branch
mds_user_clear. This static branch is never toggled after boot, and can
be safely replaced with an ALTERNATIVE() which is convenient to use in
asm.

Switch to ALTERNATIVE() to use the VERW mitigation late in exit-to-user
path. Also remove the now redundant VERW in exc_nmi() and
arch_exit_to_user_mode().

Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20240213-delay-verw-v8-4-a6216d83edb7%40linux.intel.com
2024-02-19 16:31:49 -08:00
Thomas Gleixner
89b0f15f40 x86/cpu/topology: Get rid of cpuinfo::x86_max_cores
Now that __num_cores_per_package and __num_threads_per_package are
available, cpuinfo::x86_max_cores and the related math all over the place
can be replaced with the ready to consume data.

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/20240213210253.176147806@linutronix.de
2024-02-16 15:51:32 +01:00
Thomas Gleixner
fd43b8ae76 x86/cpu/topology: Provide __num_[cores|threads]_per_package
Expose properly accounted information and accessors so the fiddling with
other topology variables can be replaced.

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/20240213210253.120958987@linutronix.de
2024-02-15 22:07:45 +01:00
Thomas Gleixner
8078f4d610 x86/cpu/topology: Rename smp_num_siblings
It's really a non-intuitive name. Rename it to __max_threads_per_core which
is obvious.

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/20240213210253.011307973@linutronix.de
2024-02-15 22:07:45 +01:00
Thomas Gleixner
3205c9833d x86/cpu/topology: Retrieve cores per package from topology bitmaps
Similar to other sizing information the number of cores per package can be
established from the topology bitmap.

Provide a function for retrieving that information and replace the buggy
hack in the CPUID evaluation with it.

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/20240213210252.956858282@linutronix.de
2024-02-15 22:07:45 +01:00
Thomas Gleixner
380414be78 x86/cpu/topology: Use topology logical mapping mechanism
Replace the logical package and die management functionality and retrieve
the logical IDs from the topology bitmaps.

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/20240213210252.901865302@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
b7065f4f84 x86/cpu/topology: Provide logical pkg/die mapping
With the topology bitmaps in place the logical package and die IDs can
trivially be retrieved by determining the bitmap weight of the relevant
topology domain level up to and including the physical ID in question.

Provide a function to that effect.

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/20240213210252.846136196@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
5e40fb2d4a x86/cpu/topology: Simplify cpu_mark_primary_thread()
No point in creating a mask via fls(). smp_num_siblings is guaranteed to be
a power of 2. So just using (smp_num_siblings - 1) has the same effect.

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/20240213210252.791176581@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
882e0cff9e x86/cpu/topology: Mop up primary thread mask handling
The early initcall to initialize the primary thread mask is not longer
required because topology_init_possible_cpus() can mark primary threads
correctly when initializing the possible and present map as the number of
SMT threads is already determined correctly.

The XENPV workaround is not longer required because XENPV now registers
fake APIC IDs which will just work like any other enumeration.

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/20240213210252.736104257@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
090610ba70 x86/cpu/topology: Use topology bitmaps for sizing
Now that all possible APIC IDs are tracked in the topology bitmaps, its
trivial to retrieve the real information from there.

This gets rid of the guesstimates for the maximal packages and dies per
package as the actual numbers can be determined before a single AP has been
brought up.

The number of SMT threads can now be determined correctly from the bitmaps
in all situations. Up to now a system which has SMT disabled in the BIOS
will still claim that it is SMT capable, because the lowest APIC ID bit is
reserved for that and CPUID leaf 0xb/0x1f still enumerates the SMT domain
accordingly. By calculating the bitmap weights of the SMT and the CORE
domain and setting them into relation the SMT disabled in BIOS situation
reports correctly that the system is not SMT capable.

It also handles the situation correctly when a hybrid systems boot CPU does
not have SMT as it takes the SMT capability of the APs fully into account.

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/20240213210252.681709880@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
354da4cf57 x86/cpu/topology: Let XEN/PV use topology from CPUID/MADT
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
2024-02-15 22:07:44 +01:00
Thomas Gleixner
ea2dd8a5d4 x86/cpu/topology: Assign hotpluggable CPUIDs during init
There is no point in assigning the CPU numbers during ACPI physical
hotplug. The number of possible hotplug CPUs is known when the possible map
is initialized, so the CPU numbers can be associated to the registered
non-present APIC IDs right there.

This allows to put more code into the __init section and makes the related
data __ro_after_init.

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/20240213210252.517339971@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
7cdcdab1a6 x86/cpu/topology: Reject unknown APIC IDs on ACPI hotplug
The topology bitmaps track all possible APIC IDs which have been registered
during enumeration. As sizing and further topology information is going to
be derived from these bitmaps, reject attempts to hotplug an APIC ID which
was not registered during enumeration.

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/20240213210252.462231229@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
f1f758a805 x86/topology: Add a mechanism to track topology via APIC IDs
Topology on X86 is determined by the registered APIC IDs and the
segmentation information retrieved from CPUID. Depending on the granularity
of the provided CPUID information the most fine grained scheme looks like
this according to Intel terminology:

   [PKG][DIEGRP][DIE][TILE][MODULE][CORE][THREAD]

Not enumerated domain levels consume 0 bits in the APIC ID. This allows to
provide a consistent view at the topology and determine other information
precisely like the number of cores in a package on hybrid systems, where
the existing assumption that number or cores == number of threads / threads
per core does not hold.

Provide per domain level bitmaps which record the APIC ID split into the
domain levels to make later evaluation of domain level specific information
simple. This allows to calculate e.g. the logical IDs without any further
extra logic.

Contrary to the existing registration mechanism this records disabled CPUs,
which are subject to later hotplug as well. That's useful for boot time
sizing of package or die dependent allocations without using heuristics.

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/20240213210252.406985021@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
5c5682b9f8 x86/cpu: Detect real BSP on crash kernels
When a kdump kernel is started from a crashing CPU then there is no
guarantee that this CPU is the real boot CPU (BSP). If the kdump kernel
tries to online the BSP then the INIT sequence will reset the machine.

There is a command line option to prevent this, but in case of nested kdump
kernels this is wrong.

But that command line option is not required at all because the real
BSP is enumerated as the first CPU by firmware. Support for the only
known system which was different (Voyager) got removed long ago.

Detect whether the boot CPU APIC ID is the first APIC ID enumerated by
the firmware. If the first APIC ID enumerated is not matching the boot
CPU APIC ID then skip registering it.

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/20240213210252.348542071@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
7c0edad364 x86/cpu/topology: Rework possible CPU management
Managing possible CPUs is an unreadable and uncomprehensible maze. Aside of
that it's backwards because it applies command line limits after
registering all APICs.

Rewrite it so that it:

  - Applies the command line limits upfront so that only the allowed amount
    of APIC IDs can be registered.

  - Applies eventual late restrictions in an understandable way

  - Uses simple min_t() calculations which are trivial to follow.

  - Provides a separate function for resetting to UP mode late in the
    bringup process.

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/20240213210252.290098853@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
0e53e7b656 x86/cpu/topology: Sanitize the APIC admission logic
Move the actually required content of generic_processor_id() into the call
sites and use common helper functions for them. This separates the early
boot registration and the ACPI hotplug mechanism completely which allows
further cleanups and improvements.

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/20240213210252.230433953@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
6055f6cf0d x86/smpboot: Make error message actually useful
"smpboot: native_kick_ap: bad cpu 33" is absolutely useless information.

Replace it with something meaningful which allows to decode the failure
condition.

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/20240213210252.170806023@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
72530464ed x86/cpu/topology: Use a data structure for topology info
Put the processor accounting into a data structure, which will gain more
topology related information in the next steps, and sanitize the accounting.

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/20240213210252.111451909@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
4c4c6f3870 x86/cpu/topology: Simplify APIC registration
Having the same check whether the number of assigned CPUs has reached the
nr_cpu_ids limit twice in the same code path is pointless. Repeating the
information that CPUs are ignored over and over is also pointless noise.

Remove the redundant check and reduce the noise by using a pr_warn_once().

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/20240213210252.050264369@linutronix.de
2024-02-15 22:07:43 +01:00
Thomas Gleixner
58aa34abe9 x86/cpu/topology: Confine topology information
Now that all external fiddling with num_processors and disabled_cpus is
gone, move the last user prefill_possible_map() into the topology code too
and remove the global visibility of these variables.

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/20240213210251.994756960@linutronix.de
2024-02-15 22:07:42 +01:00
Thomas Gleixner
cab8e164a4 x86/acpi: Dont invoke topology_register_apic() for XEN PV
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
2024-02-15 22:07:42 +01:00
Thomas Gleixner
8098428c54 x86/mpparse: Use new APIC registration function
Aside of switching over to the new interface, record the number of
registered CPUs locally, which allows to make num_processors and
disabled_cpus confined to the topology code.

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/20240213210251.830955273@linutronix.de
2024-02-15 22:07:42 +01:00
Thomas Gleixner
7d319c0fca x86/of: Use new APIC registration functions
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/20240213210251.776009244@linutronix.de
2024-02-15 22:07:42 +01:00
Thomas Gleixner
8cd01c8a68 x86/jailhouse: Use new APIC registration function
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/20240213210251.720970412@linutronix.de
2024-02-15 22:07:42 +01:00
Thomas Gleixner
ff37b09c84 x86/acpi: Use new APIC registration functions
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
2024-02-15 22:07:42 +01:00
Thomas Gleixner
4176b541c2 x86/cpu/topology: Provide separate APIC registration functions
generic_processor_info() aside of being a complete misnomer is used for
both early boot registration and ACPI CPU hotplug.

While it's arguable that this can share some code, it results in code which
is hard to understand and kept around post init for no real reason.

Also the call sites do lots of manual fiddling in topology related
variables instead of having proper interfaces for the purpose which handle
the topology internals correctly.

Provide topology_register_apic(), topology_hotplug_apic() and
topology_hotunplug_apic() which have the extra magic of the call sites
incorporated and for now are wrappers around generic_processor_info().

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/20240213210251.605007456@linutronix.de
2024-02-15 22:07:42 +01:00
Thomas Gleixner
c0a66c2847 x86/cpu/topology: Move registration out of APIC code
The APIC/CPU registration sits in the middle of the APIC code. In fact this
is a topology evaluation function and has nothing to do with the inner
workings of the local APIC.

Move it out into a file which reflects what this is about.

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/20240213210251.543948812@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
1a5d0f62d1 x86/apic: Use a proper define for invalid ACPI CPU ID
The ACPI ID for CPUs is preset with U32_MAX which is completely non
obvious. Use a proper define for it.

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/20240212154640.177504138@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
4a5f72a4a3 x86/apic: Remove yet another dubious callback
Paranoia is not wrong, but having an APIC callback which is in most
implementations a complete NOOP and in one actually looking whether the
APICID of an upcoming CPU has been registered. The same APICID which was
used to bring the CPU out of wait for startup.

That's paranoia for the paranoia sake. Remove the voodoo.

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/20240212154640.116510935@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
58d1692835 x86/apic: Remove the pointless writeback of boot_cpu_physical_apicid
There is absolutely no point to write the APIC ID which was read from the
local APIC earlier, back into the local APIC for the 64-bit UP case.

Remove that along with the apic callback which is solely there for this
pointless exercise.

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/20240212154640.055288922@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
350b5e2730 x86/mpparse: Remove the physid_t bitmap wrapper
physid_t is a wrapper around bitmap. Just remove the onion layer and use
bitmap functionality directly.

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/20240212154639.994904510@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
de6aec2417 x86/mm/numa: Move early mptable evaluation into common code
There is no reason to have the early mptable evaluation conditionally
invoked only from the AMD numa topology code.

Make it explicit and invoke it from setup_arch() right after the
corresponding ACPI init call. Remove the pointless wrapper and invoke
x86_init::mpparse::early_parse_smp_config() directly.

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/20240212154639.931761608@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
dcb7600849 x86/mpparse: Switch to new init callbacks
Now that all platforms have the new split SMP configuration callbacks set
up, flip the switch and remove the old callback pointer and mop up the
platform code.

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/20240212154639.870883080@linutronix.de
2024-02-15 22:07:41 +01:00
Thomas Gleixner
30c928691c x86/jailhouse: Prepare for separate mpparse callbacks
Provide a wrapper around the existing function and fill the new callbacks
in.

No functional change as the new callbacks are not yet operational.

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/20240212154639.683073662@linutronix.de
2024-02-15 22:07:40 +01:00
Thomas Gleixner
5faf8ec771 x86/dtb: Rename x86_dtb_init()
x86_dtb_init() is a misnomer and it really should be used as a SMP
configuration parser which is selected by the platform via
x86_init::mpparse:parse_smp_config().

Rename it to x86_dtb_parse_smp_config() in preparation for that.

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/20240212154639.495992801@linutronix.de
2024-02-15 22:07:40 +01:00
Thomas Gleixner
d0a85126b1 x86/mpparse: Prepare for callback separation
In preparation of splitting the get_smp_config() callback, rename
default_get_smp_config() to mpparse_get_smp_config() and provide an early
and late wrapper.

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/20240212154639.433811243@linutronix.de
2024-02-15 22:07:40 +01:00