commit a6846234f45801441f0e31a8b37f901ef0abd2df upstream.

Today module_frob_arch_sections() spots init sections from their
'init' prefix, and uses this to keep the init PLTs separate from the rest.

get_module_plt() uses within_module_init() to determine if a
location is in the init text or not, but this depends on whether
core code thought this was an init section.

Naturally the logic is different.

module_init_layout_section() groups the init and exit text together if
module unloading is disabled, as the exit code will never run. The result
is kernels with this configuration can't load all their modules because
there are not enough PLTs for the combined init+exit section.

A previous patch exposed module_init_layout_section(), use that so the
logic is the same.

Fixes: 055f23b74b20 ("module: check for exit sections in layout_sections() instead of module_init_section()")
Cc: stable@vger.kernel.org
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull asm-generic updates from Arnd Bergmann:
 "These are cleanups for architecture specific header files:

   - the comments in include/linux/syscalls.h have gone out of sync and
     are really pointless, so these get removed

   - The asm/bitsperlong.h header no longer needs to be architecture
     specific on modern compilers, so use a generic version for newer
     architectures that use new enough userspace compilers

   - A cleanup for virt_to_pfn/virt_to_bus to have proper type checking,
     forcing the use of pointers"

* tag 'asm-generic-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  syscalls: Remove file path comments from headers
  tools arch: Remove uapi bitsperlong.h of hexagon and microblaze
  asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch
  m68k/mm: Make pfn accessors static inlines
  arm64: memory: Make virt_to_pfn() a static inline
  ARM: mm: Make virt_to_pfn() a static inline
  asm-generic/page.h: Make pfn accessors static inlines
  xen/netback: Pass (void *) to virt_to_page()
  netfs: Pass a pointer to virt_to_page()
  cifs: Pass a pointer to virt_to_page() in cifsglob
  cifs: Pass a pointer to virt_to_page()
  riscv: mm: init: Pass a pointer to virt_to_page()
  ARC: init: Pass a pointer to virt_to_pfn() in init
  m68k: Pass a pointer to virt_to_pfn() virt_to_page()
  fs/proc/kcore.c: Pass a pointer to virt_addr_valid()

Pull arm documentation move from Jonathan Corbet:
 "Move the Arm architecture documentation under Documentation/arch/.

  This brings some order to the documentation directory, declutters the
  top-level directory, and makes the documentation organization more
  closely match that of the source"

* tag 'docs-arm-move' of git://git.lwn.net/linux:
  dt-bindings: Update Documentation/arm references
  docs: update some straggling Documentation/arm references
  crypto: update some Arm documentation references
  mips: update a reference to a moved Arm Document
  arm64: Update Documentation/arm references
  arm: update in-source documentation references
  arm: docs: Move Arm documentation to Documentation/arch/

Pull ARM updates from Russell King:

 - lots of build cleanups from Arnd spread throughout the arch/arm tree

 - replace strlcpy() with the preferred strscpy()

 - use sign_extend32() in the module linker

 - drop handle_irq() machine descriptor method

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 9315/1: fiq: include asm/mach/irq.h for prototypes
  ARM: 9314/1: tcm: move tcm_init() prototype to asm/tcm.h
  ARM: 9313/1: vdso: add missing prototypes
  ARM: 9312/1: vfp: include asm/neon.h in vfpmodule.c
  ARM: 9311/1: decompressor: move function prototypes to misc.h
  ARM: 9310/1: xip-kernel: add __inflate_kernel_data prototype
  ARM: 9309/1: add missing syscall prototypes
  ARM: 9308/1: move setup functions to header
  ARM: 9307/1: nommu: include asm/idmap.h
  ARM: 9306/1: cacheflush: avoid __flush_anon_page() missing-prototype warning
  ARM: 9305/1: add clear/copy_user_highpage declarations
  ARM: 9304/1: add prototype for function called only from asm
  ARM: 9303/1: kprobes: avoid missing-declaration warnings
  ARM: 9302/1: traps: hide unused functions on NOMMU
  ARM: 9301/1: dma-mapping: hide unused dma_contiguous_early_fixup function
  ARM: 9300/1: Replace all non-returning strlcpy with strscpy
  ARM: 9299/1: module: use sign_extend32() to extend the signedness
  ARM: 9298/1: Drop custom mdesc->handle_irq()

Pull SMP updates from Thomas Gleixner:
 "A large update for SMP management:

   - Parallel CPU bringup

     The reason why people are interested in parallel bringup is to
     shorten the (kexec) reboot time of cloud servers to reduce the
     downtime of the VM tenants.

     The current fully serialized bringup does the following per AP:

       1) Prepare callbacks (allocate, intialize, create threads)
       2) Kick the AP alive (e.g. INIT/SIPI on x86)
       3) Wait for the AP to report alive state
       4) Let the AP continue through the atomic bringup
       5) Let the AP run the threaded bringup to full online state

     There are two significant delays:

       #3 The time for an AP to report alive state in start_secondary()
          on x86 has been measured in the range between 350us and 3.5ms
          depending on vendor and CPU type, BIOS microcode size etc.

       #4 The atomic bringup does the microcode update. This has been
          measured to take up to ~8ms on the primary threads depending
          on the microcode patch size to apply.

     On a two socket SKL server with 56 cores (112 threads) the boot CPU
     spends on current mainline about 800ms busy waiting for the APs to
     come up and apply microcode. That's more than 80% of the actual
     onlining procedure.

     This can be reduced significantly by splitting the bringup
     mechanism into two parts:

       1) Run the prepare callbacks and kick the AP alive for each AP
          which needs to be brought up.

          The APs wake up, do their firmware initialization and run the
          low level kernel startup code including microcode loading in
          parallel up to the first synchronization point. (#1 and #2
          above)

       2) Run the rest of the bringup code strictly serialized per CPU
          (#3 - #5 above) as it's done today.

          Parallelizing that stage of the CPU bringup might be possible
          in theory, but it's questionable whether required surgery
          would be justified for a pretty small gain.

     If the system is large enough the first AP is already waiting at
     the first synchronization point when the boot CPU finished the
     wake-up of the last AP. That reduces the AP bringup time on that
     SKL from ~800ms to ~80ms, i.e. by a factor ~10x.

     The actual gain varies wildly depending on the system, CPU,
     microcode patch size and other factors. There are some
     opportunities to reduce the overhead further, but that needs some
     deep surgery in the x86 CPU bringup code.

     For now this is only enabled on x86, but the core functionality
     obviously works for all SMP capable architectures.

   - Enhancements for SMP function call tracing so it is possible to
     locate the scheduling and the actual execution points. That allows
     to measure IPI delivery time precisely"

* tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
  trace,smp: Add tracepoints for scheduling remotelly called functions
  trace,smp: Add tracepoints around remotelly called functions
  MAINTAINERS: Add CPU HOTPLUG entry
  x86/smpboot: Fix the parallel bringup decision
  x86/realmode: Make stack lock work in trampoline_compat()
  x86/smp: Initialize cpu_primary_thread_mask late
  cpu/hotplug: Fix off by one in cpuhp_bringup_mask()
  x86/apic: Fix use of X{,2}APIC_ENABLE in asm with older binutils
  x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it
  x86/smpboot: Support parallel startup of secondary CPUs
  x86/smpboot: Implement a bit spinlock to protect the realmode stack
  x86/apic: Save the APIC virtual base address
  cpu/hotplug: Allow "parallel" bringup up to CPUHP_BP_KICK_AP_STATE
  x86/apic: Provide cpu_primary_thread mask
  x86/smpboot: Enable split CPU startup
  cpu/hotplug: Provide a split up CPUHP_BRINGUP mechanism
  cpu/hotplug: Reset task stack state in _cpu_up()
  cpu/hotplug: Remove unused state functions
  riscv: Switch to hotplug core state synchronization
  parisc: Switch to hotplug core state synchronization
  ...

There are two global functions in fiq.c that get called from
other files through an extern declaration, but a W=1 build
warns about the header not being included before the definition:

arch/arm/kernel/fiq.c:85:5: error: no previous prototype for 'show_fiq_list' [-Werror=missing-prototypes]
arch/arm/kernel/fiq.c:159:13: error: no previous prototype for 'init_FIQ' [-Werror=missing-prototypes]

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

The kernel .data decompression is called from assembler, so it does
not need a prototype, but adding one avoids this W=1 warning:

arch/arm/kernel/head-inflate-data.c:35:12: error: no previous prototype for '__inflate_kernel_data' [-Werror=missing-prototypes]

The same file contains a few extern declarations for assembler
symbols, move those into the header as well for consistency.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

All architecture-independent system calls have prototypes in
include/linux/syscalls.h, but there are a few that only exist
on arm or that take the pt_regs directly. These cause a W=1
warning such as:

arch/arm/kernel/signal.c:186:16: error: no previous prototype for 'sys_sigreturn' [-Werror=missing-prototypes]
arch/arm/kernel/signal.c:216:16: error: no previous prototype for 'sys_rt_sigreturn' [-Werror=missing-prototypes]
arch/arm/kernel/sys_arm.c:32:17: error: no previous prototype for 'sys_arm_fadvise64_64' [-Werror=missing-prototypes]

Add prototypes for all custom syscalls on arm and add them
to asm/syscalls.h.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

A couple of functions are declared in arch/arm/mm/mmu.c rather than in a header,
which causes W=1 build warnings:

arch/arm/mm/init.c:97:13: error: no previous prototype for 'setup_dma_zone' [-Werror=missing-prototypes]
arch/arm/mm/mmu.c:118:13: error: no previous prototype for 'init_default_cache_policy' [-Werror=missing-prototypes]
arch/arm/mm/mmu.c:1195:13: error: no previous prototype for 'adjust_lowmem_bounds' [-Werror=missing-prototypes]
arch/arm/mm/mmu.c:1761:13: error: no previous prototype for 'paging_init' [-Werror=missing-prototypes]
arch/arm/mm/mmu.c:1794:13: error: no previous prototype for 'early_mm_init' [-Werror=missing-prototypes]

Move the declaratsion to asm/setup.h so they can be seen by the compiler
while building the definition.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

A couple of functions in this file are only used on MMU-enabled
builds, and never even declared otherwise, causing these build
warnings:

arch/arm/kernel/traps.c:759:6: error: no previous prototype for '__pte_error' [-Werror=missing-prototypes]
arch/arm/kernel/traps.c:764:6: error: no previous prototype for '__pmd_error' [-Werror=missing-prototypes]
arch/arm/kernel/traps.c:769:6: error: no previous prototype for '__pgd_error' [-Werror=missing-prototypes]

Protect these in an #ifdef to avoid the warnings and save a little
bit of .text space.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>