m68k: lib: Include <linux/libgcc.h> for __muldi3()

When building with W=1:

    arch/m68k/lib/muldi3.c:82:1: warning: no previous prototype for ‘__muldi3’ [-Wmissing-prototypes]
       82 | __muldi3 (DItype u, DItype v)
  | ^~~~~~~~

Fix this by including <linux/libgcc.h>.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/160c1fd14b4798f576d9649334b1d2c77db5cb07.1697008341.git.geert@linux-m68k.org

m68k: fpsp040: Fix indentation by 5 spaces

Indentation should use TABs, not spaces.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/5ab108be356a5d2a6e6d72bc418ccf1c1938e8fe.1696602993.git.geert@linux-m68k.org

m68k: Fix indentation by 2 or 5 spaces in <asm/page_mm.h>

Indentation should use TABs, not spaces.
Fix whitespace in reindented code while at it.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/2819709eee2be69c93497d4e97413bd0e05a9268.1696602993.git.geert@linux-m68k.org

m68k: kernel: Fix indentation by 7 spaces in traps.c

Indentation should use TABs, not spaces.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/d1b38c9d389c1135f7856cf5f90852c2f1584c50.1696602993.git.geert@linux-m68k.org

m68k: sun3: Fix indentation by 5 or 7 spaces

Indentation should use TABs, not spaces.
Fix whitespace in reindented code while at it.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/167216dfe9795056b7a69415695772887aca6d80.1696602993.git.geert@linux-m68k.org

m68k: Fix indentation by 7 spaces in <asm/io_mm.h>

Indentation should use TABs, not spaces.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/41ca6ab21459164a52f5f468c32ef09aee7ba3d3.1696602993.git.geert@linux-m68k.org

m68k: defconfig: Update virt_defconfig for v6.6-rc3

  - Enable CONFIG_DRM_FBDEV_EMULATION and CONFIG_FB_DEVICE (no longer
    auto-enabled since commit bb6c4507fe825f1b ("drm: fix up fbdev
    Kconfig defaults")),
  - Drop CONFIG_FRAMEBUFFER_CONSOLE=y (auto-enabled since commit
    bb6c4507fe825f1b ("drm: fix up fbdev Kconfig defaults")).

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/6f30b86b83b972e9902b62295f397a20512d5507.1695977960.git.geert@linux-m68k.org

m68k: defconfig: Update defconfigs for v6.6-rc1

  - Enable modular build of the new device model tests,
  - Enable modular build of the glob self-test on configs that didn't
    have it yet (visible since commit b67abaad4d25b5d9 ("kunit: Allow
    kunit test modules to use test filtering")),
  - Replace CONFIG_FB=y by CONFIG_FRAMEBUFFER_CONSOLE=y on the virt
    platform (the former is no longer needed since commit
    55bffc8170bb5813 ("fbdev: Split frame buffer support in FB and
    FB_CORE symbols")), the latter is no longer auto-enabled since
    commit a5ae331edb02b664 ("drm: Drop select FRAMEBUFFER_CONSOLE for
    DRM_FBDEV_EMULATION")).

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/43ef623c9053862d93fbc746689d4897b35597ef.1694442486.git.geert@linux-m68k.org

m68k: io: Mark mmio read addresses as const

Passing constant __iomem tokens into the readl() family of helpers
or any of the others causes a warning on m68k:

    include/asm-generic/io.h: In function 'ioread8_rep':
    arch/m68k/include/asm/io_mm.h:375:44: warning: passing argument 1 of 'raw_insb' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
 375 | #define readsb(port, buf, nr)     raw_insb((port), (u8

Add a 'const' modifier to the pointers to shut up the warnings here.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309251926.bPl23AhG-lkp@intel.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20230925155328.443664-1-arnd@kernel.org
[geert: Fix missed rom_in_{8,be16,le16}()]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k: Replace GPL 2.0+ README.legal boilerplate with SPDX

Upstream Linux never had a "README.legal" file, but it was present
in early source releases of Linux/m68k.  It contained a simple copyright
notice and a link to a version of the "COPYING" file that predated the
addition of the "only valid GPL version is v2" clause.

Get rid of the references to non-existent files by replacing the
boilerplate with SPDX license identifiers.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/r/23430c233728ab02ec0af8e714994398d383137a.1695031668.git.geert@linux-m68k.org

m68k: sun3: Change led_pattern[] to unsigned char

The values stored in led_pattern[] are only used for passing to
sun3_leds(), which takes an "unsigned char".
Change the type of led_pattern[] accordingly, to reduce kernel size.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/794c5d543dbdae8336a13ef2459adafaaadb7d86.1695031620.git.geert@linux-m68k.org

m68k: Add missing types to asm/irq.h

As reported in commit f8b648bf6628 ("net: sunhme: move asm includes to
below linux includes") when including this <asm/*> header before the
needed <linux/*> headers the compilation will fail because of missing
types:

    arch/m68k/include/asm/irq.h:66:20: warning: ‘struct pt_regs’ declared inside parameter list will not be visible outside of this definition or declaration
       66 |             struct pt_regs *));
  |                    ^~~~~~~
    arch/m68k/include/asm/irq.h:78:11: error: expected ‘;’ before ‘void’
       78 | asmlinkage void do_IRQ(int irq, struct pt_regs *regs);
  |           ^~~~~
  |           ;
    arch/m68k/include/asm/irq.h:78:40: warning: ‘struct pt_regs’ declared inside parameter list will not be visible outside of this definition or declaration
       78 | asmlinkage void do_IRQ(int irq, struct pt_regs *regs);
  |                                        ^~~~~~~
    arch/m68k/include/asm/irq.h:79:8: error: unknown type name ‘atomic_t’
       79 | extern atomic_t irq_err_count;
  |        ^~~~~~~~

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/5971770.lOV4Wx5bFT@eto.sf-tec.de
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k: sun3/3x: Add and use "sun3.h"

When building with W=1:

    arch/m68k/sun3/idprom.c:86:6: warning: no previous prototype for ‘sun3_get_model’ [-Wmissing-prototypes]
       86 | void sun3_get_model(char *model)
  |      ^~~~~~~~~~~~~~
    arch/m68k/sun3/config.c:53:24: warning: no previous prototype for ‘sun3_init’ [-Wmissing-prototypes]
       53 | asmlinkage void __init sun3_init(void)
  |                        ^~~~~~~~~
    arch/m68k/sun3/mmu_emu.c:117:6: warning: no previous prototype for ‘print_pte_vaddr’ [-Wmissing-prototypes]
      117 | void print_pte_vaddr (unsigned long vaddr)
  |      ^~~~~~~~~~~~~~~
    arch/m68k/sun3/mmu_emu.c:126:13: warning: no previous prototype for ‘mmu_emu_init’ [-Wmissing-prototypes]
      126 | void __init mmu_emu_init(unsigned long bootmem_end)
  |             ^~~~~~~~~~~~
    arch/m68k/sun3/mmu_emu.c:353:5: warning: no previous prototype for ‘mmu_emu_handle_fault’ [-Wmissing-prototypes]
      353 | int mmu_emu_handle_fault (unsigned long vaddr, int read_flag, int kernel_fault)
  |     ^~~~~~~~~~~~~~~~~~~~
    arch/m68k/sun3/leds.c:6:6: warning: no previous prototype for ‘sun3_leds’ [-Wmissing-prototypes]
6 | void sun3_leds(unsigned char byte)
  |      ^~~~~~~~~
    arch/m68k/sun3/intersil.c:27:5: warning: no previous prototype for ‘sun3_hwclk’ [-Wmissing-prototypes]
       27 | int sun3_hwclk(int set, struct rtc_time *t)
  |     ^~~~~~~~~~
    arch/m68k/sun3x/config.c:30:6: warning: no previous prototype for ‘sun3_leds’ [-Wmissing-prototypes]
       30 | void sun3_leds(unsigned char byte)
  |      ^~~~~~~~~

Fix this by introducing a new header file "sun3.h" for holding the
prototypes of functions implemented in arch/m68k/sun3/ and
arch/m68k/sun3x/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/87856ef9ef8955f459fb691faca921c0a688bc80.1694613528.git.geert@linux-m68k.org

m68k: sun3x: Make dvma_print() static

There was never a user of dvma_print() outside arch/m68k/sun3x/dvma.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/0a038ac68ee553b1928a975dc0ae1c16803a0ac0.1694613528.git.geert@linux-m68k.org

m68k: sun3x: Make sun3x_halt() static

When building with W=1:

    arch/m68k/sun3x/prom.c:33:6: warning: no previous prototype for ‘sun3x_halt’ [-Wmissing-prototypes]
       33 | void sun3x_halt(void)
  |      ^~~~~~~~~~

Fix this by making sun3x_halt() static.
The function body was moved to arch/m68k/sun3x/prom.c in v2.4.5.2.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/0ba2883aaff2e4fc5e570bfee87c58e483668b26.1694613528.git.geert@linux-m68k.org

m68k: sun3x: Do not mark dvma_map_iommu() inline

dvma_map_iommu() is called from the common Sun3/3x DVMA management code,
but never from inside arch/m68k/sun3x/dvma.c.  Hence it does not make
sense to mark it inline.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/0884fd1f5d6775535bf20b13cc74283df4955e49.1694613528.git.geert@linux-m68k.org

m68k: sun3x: Fix signature of sun3_leds()

The sun3_leds() implementation for Sun3 in arch/m68k/sun3/leds.c, and
the prototype in arch/m68k/sun3/sun3ints.c take an "unsigned char", not
an "int".  Align the dummy implementation for Sun3x with the Sun3
variant and the common caller.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/5214afb67eac58b8adae5710aea0980c2644ff24.1694613528.git.geert@linux-m68k.org

m68k: sun3: Make sun3_platform_init() static

When building with W=1:

    arch/m68k/sun3/config.c:201:12: warning: no previous prototype for ‘sun3_platform_init’ [-Wmissing-prototypes]
      202 | int __init sun3_platform_init(void)
  |            ^~~~~~~~~~~~~~~~~~

Fix this by making sun3_platform_init() static.
There was never a user outside arch/m68k/sun3/config.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/f35e6376d01b11f21f677cb980093e8410d2c33b.1694613528.git.geert@linux-m68k.org

m68k: sun3: Make print_pte() static

When building with W=1:

    arch/m68k/sun3/mmu_emu.c:70:6: warning: no previous prototype for ‘print_pte’ [-Wmissing-prototypes]
       70 | void print_pte (pte_t pte)
  |      ^~~~~~~~~

Fix this by making print_pte() static.
There was never a user outside arch/m68k/sun3/mmu_emu.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/a56c70e85584efb3681cb7e94aff167299dfa5e4.1694613528.git.geert@linux-m68k.org

m68k: sun3: Annotate prom_printf() with __printf()

When building with W=1:

    arch/m68k/sun3/prom/printf.c: In function ‘prom_printf’:
    arch/m68k/sun3/prom/printf.c:35:9: warning: function ‘prom_printf’ might be a candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format]
       35 |         vsprintf(ppbuf, fmt, args);
  |         ^~~~~~~~

Fix this by annotating prom_printf() with __printf(1, 2).

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/61017c012617e6f633ac9f9a3c2659ae38e1f2fb.1694613528.git.geert@linux-m68k.org

m68k: sun3: Remove unused vsprintf() return value in prom_printf()

When building with W=1:

    arch/m68k/sun3/prom/printf.c: In function ‘prom_printf’:
    arch/m68k/sun3/prom/printf.c:28:13: warning: variable ‘i’ set but not used [-Wunused-but-set-variable]
       28 |         int i;
  |             ^

As the return value of vsprintf() is unused, and serves no practical
purpose here, fix this by removing the variable.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/94a1e61b1651ff05f4a59655d9b8c1ac5338f60c.1694613528.git.geert@linux-m68k.org

m68k: sun3: Remove unused start_page in sun3_bootmem_alloc()

When building with W=1:

    arch/m68k/sun3/config.c: In function ‘sun3_bootmem_alloc’:
    arch/m68k/sun3/config.c:110:23: warning: variable ‘start_page’ set but not used [-Wunused-but-set-variable]
      112 |         unsigned long start_page;
  |                       ^~~~~~~~~~

Fix this by removing the variable and the assignment, now the last user
is gone.

Fixes: 1008a11590b966b4 ("m68k: switch to MEMBLOCK + NO_BOOTMEM")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/361c4562350c8739f6c0da34f7c416b2678fae7c.1694613528.git.geert@linux-m68k.org

m68k: sun3: Remove unused orig_baddr in free_baddr()

When building with W=1:

    arch/m68k/sun3/sun3dvma.c: In function ‘free_baddr’:
    arch/m68k/sun3/sun3dvma.c:208:23: warning: variable ‘orig_baddr’ set but not used [-Wunused-but-set-variable]
      196 |         unsigned long orig_baddr;
  |                       ^~~~~~~~~~

Fix this by removing the unused variable and assignment, which were
futile since their introduction in v2.4.5.2.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/c705b6186241dfe9a5bdcb71720b8697fa5c801f.1694613528.git.geert@linux-m68k.org

m68k: sun3: Add missing asmlinkage to sun3_init()

sun3_init() is called from assembly code, so it should be marked
asmlinkage for documentation purposes.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/9a174020de2c55e108be9bd25fcdec3e48d655c4.1694613528.git.geert@linux-m68k.org

m68k: sun3: Fix signature of sun3_get_model()

The mach_get_model() callback takes a "char *", not an
"unsigned char *".

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/c635afb4542ab54c3dbd4fa2fbed07a2665a2f4e.1694613528.git.geert@linux-m68k.org

m68k: sun3: Fix context restore in flush_tlb_range()

When building with W=1:

    In file included from arch/m68k/kernel/traps.c:42:
    arch/m68k/include/asm/tlbflush.h: In function ‘flush_tlb_range’:
    arch/m68k/include/asm/tlbflush.h:191:28: warning: variable ‘oldctx’ set but not used [-Wunused-but-set-variable]
      191 |         unsigned char seg, oldctx;
  |                            ^~~~~~

Indeed, the old context is saved, but never restored.  Fix this by
adding the missing call to sun3_put_context().

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/ea859b7850e061e0f7fb3fca64d9f8e6d1c0d2ad.1694613528.git.geert@linux-m68k.org

m68k: sun3: Improve Sun3/3x DVMA abstraction in <asm/dvma.h>

When building with W=1:

    arch/m68k/sun3/dvma.c:65:13: warning: no previous prototype for ‘sun3_dvma_init’ [-Wmissing-prototypes]
       65 | void __init sun3_dvma_init(void)
  |             ^~~~~~~~~~~~~~

    arch/m68k/sun3x/dvma.c:178:6: warning: no previous prototype for ‘dvma_unmap_iommu’ [-Wmissing-prototypes]
      179 | void dvma_unmap_iommu(unsigned long baddr, int len)
  |      ^~~~~~~~~~~~~~~~

Fix this by moving the declarations for sun3_dvma_init() and
dvma_unmap_iommu() to <asm/dvma.h>.  Avoid #ifdefs in callers by
providing dummy static inline functions.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/ec93ed1b28b75674ae9a0b42de083a9bb140f0b3.1694613528.git.geert@linux-m68k.org

m68k: sun3/3x: Include <asm/config.h> for config_sun3*()

When building with W=1:

    arch/m68k/sun3/config.c:123:13: warning: no previous prototype for ‘config_sun3’ [-Wmissing-prototypes]
      126 | void __init config_sun3(void)
  |             ^~~~~~~~~~~
    arch/m68k/sun3x/config.c:42:13: warning: no previous prototype for ‘config_sun3x’ [-Wmissing-prototypes]
       42 | void __init config_sun3x(void)
  |             ^~~~~~~~~~~~

Fix this by including <asm/config.h>

Fixes: 91d7b75a5888c182 ("m68k: Add asm/config.h")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/b9178e864d6c5e06c177d53bc4cce6d689f94d78.1694613528.git.geert@linux-m68k.org

m68k: q40: Add and use "q40.h"

When building with W=1:

    arch/m68k/q40/q40ints.c:84:13: warning: no previous prototype for ‘q40_init_IRQ’ [-Wmissing-prototypes]
       84 | void __init q40_init_IRQ(void)
  |             ^~~~~~~~~~~~
    arch/m68k/q40/q40ints.c:112:6: warning: no previous prototype for ‘q40_mksound’ [-Wmissing-prototypes]
      112 | void q40_mksound(unsigned int hz, unsigned int ticks)
  |      ^~~~~~~~~~~
    arch/m68k/q40/q40ints.c:152:6: warning: no previous prototype for ‘q40_sched_init’ [-Wmissing-prototypes]
      152 | void q40_sched_init (void)
  |      ^~~~~~~~~~~~~~

Fix this by introducing a new header file "q40.h" for holding the
prototypes of functions implemented in arch/m68k/q40/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/7f983ce079b176e1e1ac2a7d0c35b36197c5fa6b.1694613528.git.geert@linux-m68k.org

m68k: mvme16x: Add and use "mvme16x.h"

When building with W=1:

    arch/m68k/mvme16x/config.c:208:6: warning: no previous prototype for ‘mvme16x_cons_write’ [-Wmissing-prototypes]
      208 | void mvme16x_cons_write(struct console *co, const char *str, unsigned count)
  |      ^~~~~~~~~~~~~~~~~~

Fix this by introducing a new header file "mvme16x.h" for holding the
prototypes of functions implemented in arch/m68k/mvme16x/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/6200cc3b26fad215c4524748af04692e38c5ecd2.1694613528.git.geert@linux-m68k.org

m68k: mvme16x: Remove unused sink in mvme16x_cons_write()

When building with W=1:

    arch/m68k/mvme16x/config.c: In function ‘mvme16x_cons_write’:
    arch/m68k/mvme16x/config.c:211:25: warning: variable ‘sink’ set but not used [-Wunused-but-set-variable]
      211 |         volatile u_char sink;
  |                         ^~~~

Fix this by removing the unused variable and assignment.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/22c4d1978f811d7f4495eeb269ce06304717627a.1694613528.git.geert@linux-m68k.org

m68k: mvme147: Make mvme147_init_IRQ() static

When building with W=1:

    arch/m68k/mvme147/config.c:76:13: warning: no previous prototype for ‘mvme147_init_IRQ’ [-Wmissing-prototypes]
       76 | void __init mvme147_init_IRQ(void)
  |             ^~~~~~~~~~~~~~~~

Fix this by making mvme147_init_IRQ() static.
The function body was moved to arch/m68k/mvme147/config.c in v2.6.18.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/853e29ca81761032c3af132fffbd583b667234a6.1694613528.git.geert@linux-m68k.org

m68k: mac: Add and use "mac.h"

When building with W=1:

    arch/m68k/mac/iop.c:235:13: warning: no previous prototype for ‘iop_init’ [-Wmissing-prototypes]
      235 | void __init iop_init(void)
  |             ^~~~~~~~
    arch/m68k/mac/via.c:112:13: warning: no previous prototype for ‘via_init’ [-Wmissing-prototypes]
      111 | void __init via_init(void)
  |             ^~~~~~~~
    arch/m68k/mac/via.c:623:13: warning: no previous prototype for ‘via_init_clock’ [-Wmissing-prototypes]
      593 | void __init via_init_clock(void)
  |             ^~~~~~~~~~~~~~
    arch/m68k/mac/oss.c:37:13: warning: no previous prototype for ‘oss_init’ [-Wmissing-prototypes]
       37 | void __init oss_init(void)
  |             ^~~~~~~~
    arch/m68k/mac/psc.c:76:13: warning: no previous prototype for ‘psc_init’ [-Wmissing-prototypes]
       76 | void __init psc_init(void)
  |             ^~~~~~~~
    arch/m68k/mac/baboon.c:25:13: warning: no previous prototype for ‘baboon_init’ [-Wmissing-prototypes]
       25 | void __init baboon_init(void)
  |             ^~~~~~~~~~~
    arch/m68k/mac/macboing.c:155:6: warning: no previous prototype for ‘mac_mksound’ [-Wmissing-prototypes]
      155 | void mac_mksound( unsigned int freq, unsigned int length )
  |      ^~~~~~~~~~~
    arch/m68k/mac/misc.c:608:5: warning: no previous prototype for ‘mac_hwclk’ [-Wmissing-prototypes]
      608 | int mac_hwclk(int op, struct rtc_time *t)
  |     ^~~~~~~~~

Fix this by introducing a new header file "mac.h" for holding the
prototypes of functions implemented in arch/m68k/mac/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/d1fe0014a9e472a305333de4fa17f335c93d73af.1694613528.git.geert@linux-m68k.org

m68k: mac: Make mac_platform_init() static

When building with W=1:

    arch/m68k/mac/config.c:961:12: warning: no previous prototype for ‘mac_platform_init’ [-Wmissing-prototypes]
      961 | int __init mac_platform_init(void)
  |            ^~~~~~~~~~~~~~~~~

Fix this by making mac_platform_init() static.
There was never a user outside arch/m68k/mac/config.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/f5f069f94c369b7de223bb5e1a21837807fde982.1694613528.git.geert@linux-m68k.org

m68k: mac: Remove unused yday in unmktime()

When building with W=1:

    arch/m68k/mac/misc.c: In function ‘unmktime’:
    arch/m68k/mac/misc.c:557:33: warning: variable ‘yday’ set but not used [-Wunused-but-set-variable]
      557 |         int days, rem, y, wday, yday;
  |                                 ^~~~

Fix this by removing the unused variable and assignment.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/b25c42eac8beb0862f1b2041e817cb421ec66b4e.1694613528.git.geert@linux-m68k.org

m68k: mac: Remove unused sine_data[]

When building with W=1:

    arch/m68k/mac/macboing.c:29:26: warning: ‘sine_data’ defined but not used [-Wunused-const-variable=]
       29 | static const signed char sine_data[] = {
  |                          ^~~~~~~~~

The predefined sine table was superseded by a table calculated at
run-time in v2.2.0.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/75dbc0a141490daf9febfb8cb4a43ae87fbe3352.1694613528.git.geert@linux-m68k.org

m68k: hp300: Include "time.h" for hp300_sched_init()

When building with W=1:

    arch/m68k/hp300/time.c:101:13: warning: no previous prototype for ‘hp300_sched_init’ [-Wmissing-prototypes]
      101 | void __init hp300_sched_init(void)
  |             ^~~~~~~~~~~~~~~~

Fix this by including "time.h".

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/630ee35241dc753a30b69adedc2ffa8fc6d551dd.1694613528.git.geert@linux-m68k.org

m68k: bvme6000: Make bvme6000_abort_int() static

When building with W=1:

    arch/m68k/bvme6000/config.c:133:13: warning: no previous prototype for ‘bvme6000_abort_int’ [-Wmissing-prototypes]
      133 | irqreturn_t bvme6000_abort_int (int irq, void *dev_id)
  |             ^~~~~~~~~~~~~~~~~~

Fix this by making bvme6000_abort_int() static.
There was never a user outside arch/m68k/bvme6000/config.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/4da40748e1d7d56b73840a1d7ab1cb9c9a59cef2.1694613528.git.geert@linux-m68k.org

m68k: apollo: Add and use "apollo.h"

When building with W=1:

    arch/m68k/apollo/dn_ints.c:43:13: warning: no previous prototype for ‘dn_init_IRQ’ [-Wmissing-prototypes]
       43 | void __init dn_init_IRQ(void)
  |             ^~~~~~~~~~~

Fix this by introducing a new header file "apollo.h" for holding the
prototypes of functions implemented in arch/m68k/apollo/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/d78eceb83b8dd1931be1789204898060664e23f6.1694613528.git.geert@linux-m68k.org

m68k: apollo: Replace set but not used variable by READ_ONCE()

When building with W=1:

    arch/m68k/apollo/config.c: In function ‘dn_timer_int’:
    arch/m68k/apollo/config.c:171:32: warning: variable ‘x’ set but not used [-Wunused-but-set-variable]
      149 |         volatile unsigned char x;
  |                                ^

Fix this by using READ_ONCE(), and removing the variable.
As READ_ONCE() casts to volatile internally, remove the existing cast.
Deduplicate the remaining casts by introducing an intermediary.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/d0299797d6bf747eca2da998c6c6256485a9f52e.1694613528.git.geert@linux-m68k.org

m68k: apollo: Make local reset, serial, and irq functions static

When building with W=1:

    arch/m68k/apollo/config.c:132:6: warning: no previous prototype for ‘dn_serial_print’ [-Wmissing-prototypes]
      110 | void dn_serial_print (const char *str)
  |      ^~~~~~~~~~~~~~~
    arch/m68k/apollo/dn_ints.c:8:14: warning: no previous prototype for ‘apollo_irq_startup’ [-Wmissing-prototypes]
8 | unsigned int apollo_irq_startup(struct irq_data *data)
  |              ^~~~~~~~~~~~~~~~~~
    arch/m68k/apollo/dn_ints.c:19:6: warning: no previous prototype for ‘apollo_irq_shutdown’ [-Wmissing-prototypes]
       19 | void apollo_irq_shutdown(struct irq_data *data)
  |      ^~~~~~~~~~~~~~~~~~~
    arch/m68k/apollo/dn_ints.c:29:6: warning: no previous prototype for ‘apollo_irq_eoi’ [-Wmissing-prototypes]
       29 | void apollo_irq_eoi(struct irq_data *data)
  |      ^~~~~~~~~~~~~~

Fix this by making all local functions static.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/d2b3a6785d3e80069fea85921c72cf0b7afb8493.1694613528.git.geert@linux-m68k.org

m68k: apollo: Remove unused debug console functions

When building with W=1:

    arch/m68k/apollo/config.c:111:5: warning: no previous prototype for ‘dn_serial_console_wait_key’ [-Wmissing-prototypes]
      111 | int dn_serial_console_wait_key(struct console *co) {
  |     ^~~~~~~~~~~~~~~~~~~~~~~~~~
    arch/m68k/apollo/config.c:118:6: warning: no previous prototype for ‘dn_serial_console_write’ [-Wmissing-prototypes]
      118 | void dn_serial_console_write (struct console *co, const char *str,unsigned int count)
  |      ^~~~~~~~~~~~~~~~~~~~~~~
    arch/m68k/apollo/config.c:238:6: warning: no previous prototype for ‘dn_dummy_waitbut’ [-Wmissing-prototypes]
      240 | void dn_dummy_waitbut(void) {
  |      ^~~~~~~~~~~~~~~~

Fix this by removing these unused functions.
The last user of dn_serial_console_write() was removed in v2.3.41.
The other functions never had any users.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/5da9036914a5c84c20b6af55f1801f0c734a96bb.1694613528.git.geert@linux-m68k.org

m68k: atari: Add and use "atari.h"

When building with W=1:

    arch/m68k/atari/time.c:59:1: warning: no previous prototype for ‘atari_sched_init’ [-Wmissing-prototypes]
       59 | atari_sched_init(void)
  | ^~~~~~~~~~~~~~~~
    arch/m68k/atari/time.c:140:5: warning: no previous prototype for ‘atari_mste_hwclk’ [-Wmissing-prototypes]
      140 | int atari_mste_hwclk( int op, struct rtc_time *t )
  |     ^~~~~~~~~~~~~~~~
    arch/m68k/atari/time.c:199:5: warning: no previous prototype for ‘atari_tt_hwclk’ [-Wmissing-prototypes]
      199 | int atari_tt_hwclk( int op, struct rtc_time *t )
  |     ^~~~~~~~~~~~~~
    arch/m68k/atari/ataints.c:267:13: warning: no previous prototype for ‘atari_init_IRQ’ [-Wmissing-prototypes]
      267 | void __init atari_init_IRQ(void)
  |             ^~~~~~~~~~~~~~
    arch/m68k/atari/atasound.c:36:6: warning: no previous prototype for ‘atari_microwire_cmd’ [-Wmissing-prototypes]
       36 | void atari_microwire_cmd (int cmd)
  |      ^~~~~~~~~~~~~~~~~~~
    arch/m68k/atari/atasound.c:53:6: warning: no previous prototype for ‘atari_mksound’ [-Wmissing-prototypes]
       53 | void atari_mksound (unsigned int hz, unsigned int ticks)
  |      ^~~~~~~~~~~~~

Fix this by introducing a new header file "atari.h" for holding the
prototypes of functions implemented in arch/m68k/atari/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/336e4a478ccbfd7e3e91cdbd27636947587a23a6.1694613528.git.geert@linux-m68k.org

m68k: atari: Make atari_stram_map_pages() static

When building with W=1:

    arch/m68k/atari/stram.c:118:12: warning: no previous prototype for ‘atari_stram_map_pages’ [-Wmissing-prototypes]
      118 | int __init atari_stram_map_pages(void)
  |            ^~~~~~~~~~~~~~~~~~~~~

Fix this by making atari_stram_map_pages() static.
There was never a user outside arch/m68k/atari/stram.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/fa86b6d7e54d96ac52f574ed00f96e339f46990f.1694613528.git.geert@linux-m68k.org

m68k: atari: Make atari_platform_init() static

When building with W=1:

    arch/m68k/atari/config.c:883:12: warning: no previous prototype for ‘atari_platform_init’ [-Wmissing-prototypes]
      883 | int __init atari_platform_init(void)
  |            ^~~~~~~~~~~~~~~~~~~

Fix this by making atari_platform_init() static.
There was never a user outside arch/m68k/atari/config.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/417b46ec1945212c0b1fcc8b0f4074bae9a8b0b4.1694613528.git.geert@linux-m68k.org

m68k: atari: Make ikbd_reset() static

When building with W=1:

    arch/m68k/atari/atakeyb.c:335:6: warning: no previous prototype for ‘ikbd_reset’ [-Wmissing-prototypes]
      335 | void ikbd_reset(void)
  |      ^~~~~~~~~~

Fix this by making ikbd_reset() static.
There was never a user outside arch/m68k/atari/atakey.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/6babf691fff55f913808ad845e66f60ab00063b2.1694613528.git.geert@linux-m68k.org

m68k: atari: Document data parameter of stdma_try_lock()

When building with W=1:

    arch/m68k/atari/stdma.c:69: warning: Function parameter or member 'data' not described in 'stdma_try_lock'

Fix this by documenting the data parameter.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/a69dd3ab0a224e40ce5ce7b30981e2d7a0285a83.1694613528.git.geert@linux-m68k.org

m68k: amiga: Add and use "amiga.h"

When building with W=1:

    arch/m68k/amiga/amisound.c:48:13: warning: no previous prototype for ‘amiga_init_sound’ [-Wmissing-prototypes]
       48 | void __init amiga_init_sound(void)
  |             ^~~~~~~~~~~~~~~~
    arch/m68k/amiga/amisound.c:71:6: warning: no previous prototype for ‘amiga_mksound’ [-Wmissing-prototypes]
       71 | void amiga_mksound( unsigned int hz, unsigned int ticks )
  |      ^~~~~~~~~~~~~

Fix this by introducing a new header file "amiga.h" for holding the
prototypes of functions implemented in arch/m68k/amiga/.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/7e9395e1de1c9a34d16ea40a522057f05bbee400.1694613528.git.geert@linux-m68k.org

m68k: amiga: pcmcia: Replace set but not used variable by READ_ONCE()

When building with W=1:

    arch/m68k/amiga/pcmcia.c: In function ‘pcmcia_reset’:
    arch/m68k/amiga/pcmcia.c:29:23: warning: variable ‘b’ set but not used [-Wunused-but-set-variable]
       29 |         unsigned char b;
  |                       ^

Fix this by using READ_ONCE(), and removing the variable.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/1436fa6b329c2212aaf020055afbb97e64b6f039.1694613528.git.geert@linux-m68k.org

m68k: emu: Mark version[] __maybe_unused

When building with W=1:

    arch/m68k/emu/nfeth.c:42:19: warning: ‘version’ defined but not used [-Wunused-const-variable=]
       42 | static const char version[] =
  |                   ^~~~~~~

Fix this while obeying the wishes of the original copyright holders by
marking version[] with __maybe_unused.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/051731639b4c8e296ec4017595051885cc551c23.1694613528.git.geert@linux-m68k.org

m68k: emu: Remove unused vsnprintf() return value in nfprint()

When building with W=1:

    arch/m68k/emu/natfeat.c: In function ‘nfprint’:
    arch/m68k/emu/natfeat.c:59:13: warning: variable ‘n’ set but not used [-Wunused-but-set-variable]
       59 |         int n;
  |             ^

As the return value of vsnprintf() is unused, and serves no practical
purpose here, fix this by removing the variable.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/a8b6b17ff352cc560d1848a92d171bb0f44ccb27.1694613528.git.geert@linux-m68k.org

m68k: mm: Add and use "fault.h"

When building with W=1:

    arch/m68k/mm/fault.c:22:5: warning: no previous prototype for ‘send_fault_sig’ [-Wmissing-prototypes]
       22 | int send_fault_sig(struct pt_regs *regs)
  |     ^~~~~~~~~~~~~~
    arch/m68k/mm/fault.c:68:5: warning: no previous prototype for ‘do_page_fault’ [-Wmissing-prototypes]
       68 | int do_page_fault(struct pt_regs *regs, unsigned long address,
  |     ^~~~~~~~~~~~~

Fix this by introducing a new header file "fault.h" for holding the
prototypes of functions implemented in arch/m68k/mm/fault.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/ef004b8cfe4aac892aa0fb7714c2ed81a02a9b89.1694613528.git.geert@linux-m68k.org

m68k: mm: Move paging_init() to common <asm/pgtable.h>

When building with W=1:

    arch/m68k/mm/motorola.c:414:13: warning: no previous prototype for ‘paging_init’ [-Wmissing-prototypes]
      414 | void __init paging_init(void)
  |             ^~~~~~~~~~~
    arch/m68k/mm/sun3mmu.c:36:13: warning: no previous prototype for ‘paging_init’ [-Wmissing-prototypes]
       36 | void __init paging_init(void)
  |             ^~~~~~~~~~~

Fix this by consolidating the multiple prototypes into the common
<asm/pgtable.h>.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/1b03fde54f205e972e19959b8e335022205d538c.1694613528.git.geert@linux-m68k.org

m68k: mm: Include <asm/hwtest.h> for hwreg_()

When building with W=1:

    arch/m68k/mm/hwtest.c:29:5: warning: no previous prototype for ‘hwreg_present’ [-Wmissing-prototypes]
       29 | int hwreg_present(volatile void *regp)
  |     ^~~~~~~~~~~~~
    arch/m68k/mm/hwtest.c:62:5: warning: no previous prototype for ‘hwreg_write’ [-Wmissing-prototypes]
       62 | int hwreg_write(volatile void *regp, unsigned short val)
  |     ^~~~~~~~~~~

Fix this by including <asm/hwtest.h>.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/fbd87d8e8d1e8cbe7d56941a8a1d7d82b53010d0.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use "vectors.h"

When building with W=1:

    arch/m68k/kernel/vectors.c:52:13: warning: no previous prototype for ‘base_trap_init’ [-Wmissing-prototypes]
       52 | void __init base_trap_init(void)
  |             ^~~~~~~~~~~~~~

Fix this by introducing a new header file "vectors.h" for holding the
prototypes of functions implemented in arch/m68k/kernel/vectors.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/bd0a2f65bc1681dc45e2b24951bd89f9ddbe2eef.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use "traps.h"

When building with W=1:

    arch/m68k/kernel/traps.c:754:17: warning: no previous prototype for ‘buserr_c’ [-Wmissing-prototypes]
      754 | asmlinkage void buserr_c(struct frame *fp)
  |                 ^~~~~~~~
    arch/m68k/kernel/traps.c:1140:17: warning: no previous prototype for ‘set_esp0’ [-Wmissing-prototypes]
     1140 | asmlinkage void set_esp0(unsigned long ssp)
  |                 ^~~~~~~~
    arch/m68k/kernel/traps.c:1155:17: warning: no previous prototype for ‘fpemu_signal’ [-Wmissing-prototypes]
     1155 | asmlinkage void fpemu_signal(int signal, int code, void *addr)
  |                 ^~~~~~~~~~~~
    arch/m68k/kernel/traps.c:1149:17: warning: no previous prototype for ‘fpsp040_die’ [-Wmissing-prototypes]
     1149 | asmlinkage void fpsp040_die(void)
  |                 ^~~~~~~~~~~

Fix this by introducing a new header file "traps.h" for holding the
prototypes of functions implemented in arch/m68k/kernel/traps.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/652cbbb1c9e339980a86068ebdd0a69362324af8.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use "signal.h"

When building with W=1:

    arch/m68k/kernel/signal.c:756:18: warning: no previous prototype for ‘do_sigreturn’ [-Wmissing-prototypes]
      756 | asmlinkage void *do_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
  |                  ^~~~~~~~~~~~
    arch/m68k/kernel/signal.c:783:18: warning: no previous prototype for ‘do_rt_sigreturn’ [-Wmissing-prototypes]
      783 | asmlinkage void *do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw)
  |                  ^~~~~~~~~~~~~~~
    arch/m68k/kernel/signal.c:1112:17: warning: no previous prototype for ‘do_notify_resume’ [-Wmissing-prototypes]
     1112 | asmlinkage void do_notify_resume(struct pt_regs *regs)
  |                 ^~~~~~~~~~~~~~~~

Fix this by introducing a new header file "signal.h" for holding the
prototypes of functions implemented in arch/m68k/kernel/signal.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/25cecda80698829cec18721a9d0f058cc69df0cc.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use "ptrace.h"

When building with W=1:

    arch/m68k/kernel/ptrace.c:275:16: warning: no previous prototype for ‘syscall_trace_enter’ [-Wmissing-prototypes]
      275 | asmlinkage int syscall_trace_enter(void)
  |                ^~~~~~~~~~~~~~~~~~~
    arch/m68k/kernel/ptrace.c:288:17: warning: no previous prototype for ‘syscall_trace_leave’ [-Wmissing-prototypes]
      288 | asmlinkage void syscall_trace_leave(void)
  |                 ^~~~~~~~~~~~~~~~~~~

Fix this by introducing a new header file "ptrace.h" for holding the
prototypes of functions implemented in arch/m68k/kernel/ptrace.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/b4b3577b2149ebd65c3b3c7acccebc0e7e596f9d.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use "process.h"

When building with W=1:

    arch/m68k/kernel/process.c:115:16: warning: no previous prototype for ‘m68k_clone’ [-Wmissing-prototypes]
      115 | asmlinkage int m68k_clone(struct pt_regs *regs)
  |                ^~~~~~~~~~
    arch/m68k/kernel/process.c:136:16: warning: no previous prototype for ‘m68k_clone3’ [-Wmissing-prototypes]
      136 | asmlinkage int m68k_clone3(struct pt_regs *regs)
  |                ^~~~~~~~~~~

Fix this by introducing a new header file "process.h" for holding the
prototypes of functions implemented in arch/m68k/kernel/process.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/5e50257d8fcae3eb202ce5f439dc29c09cb6c44f.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use "ints.h"

When building with W=1:

    arch/m68k/kernel/ints.c:165:17: warning: no previous prototype for ‘handle_badint’ [-Wmissing-prototypes]
      165 | asmlinkage void handle_badint(struct pt_regs *regs)
  |                 ^~~~~~~~~~~~~

Fix this by introducing a new header file "ints.h" for holding the
prototypes of functions implemented in arch/m68k/kernel/ints.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/dc65d01ca4c7de94ce814e5b5e1f726fff97566b.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add and use <asm/syscalls.h>

When building with W=1:

    arch/m68k/kernel/sys_m68k.c:40:17: warning: no previous prototype for ‘sys_mmap2’ [-Wmissing-prototypes]
       40 | asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
  |                 ^~~~~~~~~
    arch/m68k/kernel/sys_m68k.c:378:1: warning: no previous prototype for ‘sys_cacheflush’ [-Wmissing-prototypes]
      378 | sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len)
  | ^~~~~~~~~~~~~~
    arch/m68k/kernel/sys_m68k.c:463:1: warning: no previous prototype for ‘sys_atomic_cmpxchg_32’ [-Wmissing-prototypes]
      463 | sys_atomic_cmpxchg_32(unsigned long newval, int oldval, int d3, int d4, int d5,
  | ^~~~~~~~~~~~~~~~~~~~~
    arch/m68k/kernel/sys_m68k.c:564:16: warning: no previous prototype for ‘sys_getpagesize’ [-Wmissing-prototypes]
      564 | asmlinkage int sys_getpagesize(void)
  |                ^~~~~~~~~~~~~~~
    arch/m68k/kernel/sys_m68k.c:569:26: warning: no previous prototype for ‘sys_get_thread_area’ [-Wmissing-prototypes]
      569 | asmlinkage unsigned long sys_get_thread_area(void)
  |                          ^~~~~~~~~~~~~~~~~~~
    arch/m68k/kernel/sys_m68k.c:574:16: warning: no previous prototype for ‘sys_set_thread_area’ [-Wmissing-prototypes]
      574 | asmlinkage int sys_set_thread_area(unsigned long tp)
  |                ^~~~~~~~~~~~~~~~~~~
    arch/m68k/kernel/sys_m68k.c:580:16: warning: no previous prototype for ‘sys_atomic_barrier’ [-Wmissing-prototypes]
      580 | asmlinkage int sys_atomic_barrier(void)
  |                ^~~~~~~~~~~~~~~~~~

Fix this by introducing a new header file <asm/syscalls.h> for holding
the prototypes for m68k-specific syscalls, and including the generic
ones.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/80b721eeb499562cd5d49887b0eee10dd172c88d.1694613528.git.geert@linux-m68k.org

m68k: kernel: Make bad_super_trap() static

When building with W=1:

    arch/m68k/kernel/traps.c:968:6: warning: no previous prototype for ‘bad_super_trap’ [-Wmissing-prototypes]
      968 | void bad_super_trap (struct frame *fp)
  |      ^~~~~~~~~~~~~~

Fix this by making bad_super_trap() static.
There was never a user outside arch/m68k/kernel/traps.c.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/1e0b67a355d7e1bcb40811eced41d3080e8f4d20.1694613528.git.geert@linux-m68k.org

m68k: kernel: Include <linux/cpu.h> for trap_init()

When building with W=1:

    arch/m68k/kernel/vectors.c:74:13: warning: no previous prototype for ‘trap_init’ [-Wmissing-prototypes]
       74 | void __init trap_init (void)
  |             ^~~~~~~~~

Fix this by including <linux/cpu.h>.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/42e7055fab50deda1f7cd648982e90b7ab28fdc3.1694613528.git.geert@linux-m68k.org

m68k: kernel: Add missing asmlinkage to do_notify_resume()

do_notify_resume() is called from assembly code, so it should be marked
asmlinkage for documentation purposes.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/e24d63ec4332316e859125caa8d07c0589603cfd.1694613528.git.geert@linux-m68k.org

m68k: Use kernel's generic libgcc functions

The arch/m68k/lib versions of the libgcc functions: ashldi3, ashrdi3
and lshrdi3 were taken directly from an older version of gcc.
We can use the kernel's own generic lib versions of these - they are
virtually identical. Switch to those and remove the m68k local ones.

Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20230913071350.1939818-1-gerg@kernel.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k: emu: Replace strlcpy() with strscpy()

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().

Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20230830185428.4109426-1-azeemshaikh38@gmail.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k: math-emu: Add missing prototypes

When building with W=1:

    arch/m68k/math-emu/fp_arith.c:301:16: warning: no previous prototype for ‘fp_fsglmul’ [-Wmissing-prototypes]
      301 | struct fp_ext *fp_fsglmul(struct fp_ext *dest, struct fp_ext *src)
  |                ^~~~~~~~~~
    arch/m68k/math-emu/fp_arith.c:357:16: warning: no previous prototype for ‘fp_fsgldiv’ [-Wmissing-prototypes]
      357 | struct fp_ext *fp_fsgldiv(struct fp_ext *dest, struct fp_ext *src)
  |                ^~~~~~~~~~
      CC      arch/m68k/math-emu/fp_log.o
    ...

Fix this by adding the missing prototypes to header files.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230810141947.1236730-17-arnd@kernel.org/
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/96c039640d76973ea762d79018de0bc75bbdc1dc.1692283195.git.geert@linux-m68k.org

m68k: math-emu: Reformat function and variable headers

Make the code shorter and easier to read.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/11506b9225e281f2453a83a02ac4793d0e58b609.1692283195.git.geert@linux-m68k.org

m68k: math-emu: Replace external declarations by header inclusion

Replace the (incorrect) external declarations by an inclusion of the
appropriate header file.

Semantically, the "src" parameters of the various fp_*() functions are
constant.  However, they cannot actually be const as most of these
functions perform a normalization step first.  As the fp_one constant
passed to fp_add() is already normalized, it is safe to cast away its
constness when making the function call.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/163bc2f64b5a3dd7b96a12aaca6733b408ddc880.1692283195.git.geert@linux-m68k.org

m68k: math-emu: Make multi_arith.h self-contained

Add the missing #include "fp_emu.h".

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/2efd6610e97dd1621e7d28bf87cb79173285545d.1692283195.git.geert@linux-m68k.org

m68k: math-emu: Sanitize include guards

Some include guards start with an underscore, others don't.
Some comments do not match the actual include guard.

Make them uniform, adhering to the "FP_<FOO>_H" format.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/8c84c8bf06c0c1e463c47f071891e2e83d5abdd2.1692283195.git.geert@linux-m68k.org

m68k: math-emu: Fix incorrect file reference in fp_log.c

The file comment header refers to the wrong file.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/faf2244c3c80a4d70da5a18dd2a170a15b3ebd88.1692283195.git.geert@linux-m68k.org

Linux 6.6-rc3

Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
"ARM:

   - Fix EL2 Stage-1 MMIO mappings where a random address was used

   - Fix SMCCC function number comparison when the SVE hint is set

  RISC-V:

   - Fix KVM_GET_REG_LIST API for ISA_EXT registers

   - Fix reading ISA_EXT register of a missing extension

   - Fix ISA_EXT register handling in get-reg-list test

   - Fix filtering of AIA registers in get-reg-list test

  x86:

   - Fixes for TSC_AUX virtualization

   - Stop zapping page tables asynchronously, since we don't zap them as
     often as before"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: SVM: Do not use user return MSR support for virtualized TSC_AUX
  KVM: SVM: Fix TSC_AUX virtualization setup
  KVM: SVM: INTERCEPT_RDTSCP is never intercepted anyway
  KVM: x86/mmu: Stop zapping invalidated TDP MMU roots asynchronously
  KVM: x86/mmu: Do not filter address spaces in for_each_tdp_mmu_root_yield_safe()
  KVM: x86/mmu: Open code leaf invalidation from mmu_notifier
  KVM: riscv: selftests: Selectively filter-out AIA registers
  KVM: riscv: selftests: Fix ISA_EXT register handling in get-reg-list
  RISC-V: KVM: Fix riscv_vcpu_get_isa_ext_single() for missing extensions
  RISC-V: KVM: Fix KVM_GET_REG_LIST API for ISA_EXT registers
  KVM: selftests: Assert that vasprintf() is successful
  KVM: arm64: nvhe: Ignore SVE hint in SMCCC function ID
  KVM: arm64: Properly return allocated EL2 VA from hyp_alloc_private_va_range()

Merge tag 'trace-v6.6-rc2' of git://git./linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix the "bytes" output of the per_cpu stat file

   The tracefs/per_cpu/cpu*/stats "bytes" was giving bogus values as the
   accounting was not accurate. It is suppose to show how many used
   bytes are still in the ring buffer, but even when the ring buffer was
   empty it would still show there were bytes used.

 - Fix a bug in eventfs where reading a dynamic event directory (open)
   and then creating a dynamic event that goes into that diretory screws
   up the accounting.

   On close, the newly created event dentry will get a "dput" without
   ever having a "dget" done for it. The fix is to allocate an array on
   dir open to save what dentries were actually "dget" on, and what ones
   to "dput" on close.

* tag 'trace-v6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Remember what dentries were created on dir open
  ring-buffer: Fix bytes info in per_cpu buffer stats

Merge tag 'cxl-fixes-6.6-rc3' of git://git./linux/kernel/git/cxl/cxl

Pull cxl fixes from Dan Williams:
 "A collection of regression fixes, bug fixes, and some small cleanups
  to the Compute Express Link code.

  The regressions arrived in the v6.5 dev cycle and missed the v6.6
  merge window due to my personal absences this cycle. The most
  important fixes are for scenarios where the CXL subsystem fails to
  parse valid region configurations established by platform firmware.
  This is important because agreement between OS and BIOS on the CXL
  configuration is fundamental to implementing "OS native" error
  handling, i.e. address translation and component failure
  identification.

  Other important fixes are a driver load error when the BIOS lets the
  Linux PCI core handle AER events, but not CXL memory errors.

  The other fixex might have end user impact, but for now are only known
  to trigger in our test/emulation environment.

  Summary:

   - Fix multiple scenarios where platform firmware defined regions fail
     to be assembled by the CXL core.

   - Fix a spurious driver-load failure on platforms that enable OS
     native AER, but not OS native CXL error handling.

   - Fix a regression detecting "poison" commands when "security"
     commands are also defined.

   - Fix a cxl_test regression with the move to centralize CXL port
     register enumeration in the CXL core.

   - Miscellaneous small fixes and cleanups"

* tag 'cxl-fixes-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  cxl/acpi: Annotate struct cxl_cxims_data with __counted_by
  cxl/port: Fix cxl_test register enumeration regression
  cxl/region: Refactor granularity select in cxl_port_setup_targets()
  cxl/region: Match auto-discovered region decoders by HPA range
  cxl/mbox: Fix CEL logic for poison and security commands
  cxl/pci: Replace host_bridge->native_aer with pcie_aer_is_native()
  PCI/AER: Export pcie_aer_is_native()
  cxl/pci: Fix appropriate checking for _OSC while handling CXL RAS registers

Merge tag 'gpio-fixes-for-v6.6-rc3' of git://git./linux/kernel/git/brgl/linux

Pull gpio fixes from Bartosz Golaszewski:

 - fix an invalid usage of __free(kfree) leading to kfreeing an
   ERR_PTR()

 - fix an irq domain leak in gpio-tb10x

 - MAINTAINERS update

* tag 'gpio-fixes-for-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpio: sim: fix an invalid __free() usage
  gpio: tb10x: Fix an error handling path in tb10x_gpio_probe()
  MAINTAINERS: gpio-regmap: make myself a maintainer of it

Merge tag 'mm-hotfixes-stable-2023-09-23-10-31' of git://git./linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "13 hotfixes, 10 of which pertain to post-6.5 issues. The other three
  are cc:stable"

* tag 'mm-hotfixes-stable-2023-09-23-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  proc: nommu: fix empty /proc/<pid>/maps
  filemap: add filemap_map_order0_folio() to handle order0 folio
  proc: nommu: /proc/<pid>/maps: release mmap read lock
  mm: memcontrol: fix GFP_NOFS recursion in memory.high enforcement
  pidfd: prevent a kernel-doc warning
  argv_split: fix kernel-doc warnings
  scatterlist: add missing function params to kernel-doc
  selftests/proc: fixup proc-empty-vm test after KSM changes
  revert "scripts/gdb/symbols: add specific ko module load command"
  selftests: link libasan statically for tests with -fsanitize=address
  task_work: add kerneldoc annotation for 'data' argument
  mm: page_alloc: fix CMA and HIGHATOMIC landing on the wrong buddy list
  sh: mm: re-add lost __ref to ioremap_prot() to fix modpost warning

Merge tag '6.6-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull smb client fixes from Steve French:
 "Six smb3 client fixes, including three for stable, from the SMB
  plugfest (testing event) this week:

   - Reparse point handling fix (found when investigating dir
     enumeration when fifo in dir)

   - Fix excessive thread creation for dir lease cleanup

   - UAF fix in negotiate path

   - remove duplicate error message mapping and fix confusing warning
     message

   - add dynamic trace point to improve debugging RDMA connection
     attempts"

* tag '6.6-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: fix confusing debug message
  smb: client: handle STATUS_IO_REPARSE_TAG_NOT_HANDLED
  smb3: remove duplicate error mapping
  cifs: Fix UAF in cifs_demultiplex_thread()
  smb3: do not start laundromat thread when dir leases  disabled
  smb3: Add dynamic trace points for RDMA (smbdirect) reconnect

Merge tag 'i2c-for-6.6-rc3' of git://git./linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "A set of I2C driver fixes. Mostly fixing resource leaks or sanity
  checks"

* tag 'i2c-for-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: xiic: Correct return value check for xiic_reinit()
  i2c: mux: gpio: Add missing fwnode_handle_put()
  i2c: mux: demux-pinctrl: check the return value of devm_kstrdup()
  i2c: designware: fix __i2c_dw_disable() in case master is holding SCL low
  i2c: i801: unregister tco_pdev in i801_probe() error path

mfd: cs42l43: Use correct macro for new-style PM runtime ops

The code was accidentally mixing new and old style macros, update the
macros used to remove an unused function warning whilst building with
no PM enabled in the config.

Fixes: ace6d1448138 ("mfd: cs42l43: Add support for cs42l43 core driver")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/all/20230822114914.340359-1-ckeepax@opensource.cirrus.com/
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Lee Jones <lee@kernel.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'loongarch-fixes-6.6-1' of git://git./linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch fixes from Huacai Chen:
 "Fix lockdep, fix a boot failure, fix some build warnings, fix document
  links, and some cleanups"

* tag 'loongarch-fixes-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  docs/zh_CN/LoongArch: Update the links of ABI
  docs/LoongArch: Update the links of ABI
  LoongArch: Don't inline kasan_mem_to_shadow()/kasan_shadow_to_mem()
  kasan: Cleanup the __HAVE_ARCH_SHADOW_MAP usage
  LoongArch: Set all reserved memblocks on Node#0 at initialization
  LoongArch: Remove dead code in relocate_new_kernel
  LoongArch: Use _UL() and _ULL()
  LoongArch: Fix some build warnings with W=1
  LoongArch: Fix lockdep static memory detection

Merge tag 's390-6.6-3' of git://git./linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - Fix potential string buffer overflow in hypervisor user-defined
   certificates handling

 - Update defconfigs

* tag 's390-6.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/cert_store: fix string length handling
  s390: update defconfigs

Merge tag 'iomap-6.6-fixes-2' of git://git./fs/xfs/xfs-linux

Pull iomap fixes from Darrick Wong:

 - Return EIO on bad inputs to iomap_to_bh instead of BUGging, to deal
   less poorly with block device io racing with block device resizing

 - Fix a stale page data exposure bug introduced in 6.6-rc1 when
   unsharing a file range that is not in the page cache

* tag 'iomap-6.6-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: convert iomap_unshare_iter to use large folios
  iomap: don't skip reading in !uptodate folios when unsharing a range
  iomap: handle error conditions more gracefully in iomap_to_bh

Merge tag 'kvm-riscv-fixes-6.6-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv fixes for 6.6, take #1

- Fix KVM_GET_REG_LIST API for ISA_EXT registers
- Fix reading ISA_EXT register of a missing extension
- Fix ISA_EXT register handling in get-reg-list test
- Fix filtering of AIA registers in get-reg-list test

KVM: SVM: Do not use user return MSR support for virtualized TSC_AUX

When the TSC_AUX MSR is virtualized, the TSC_AUX value is swap type "B"
within the VMSA. This means that the guest value is loaded on VMRUN and
the host value is restored from the host save area on #VMEXIT.

Since the value is restored on #VMEXIT, the KVM user return MSR support
for TSC_AUX can be replaced by populating the host save area with the
current host value of TSC_AUX. And, since TSC_AUX is not changed by Linux
post-boot, the host save area can be set once in svm_hardware_enable().
This eliminates the two WRMSR instructions associated with the user return
MSR support.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <d381de38eb0ab6c9c93dda8503b72b72546053d7.1694811272.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: Fix TSC_AUX virtualization setup

The checks for virtualizing TSC_AUX occur during the vCPU reset processing
path. However, at the time of initial vCPU reset processing, when the vCPU
is first created, not all of the guest CPUID information has been set. In
this case the RDTSCP and RDPID feature support for the guest is not in
place and so TSC_AUX virtualization is not established.

This continues for each vCPU created for the guest. On the first boot of
an AP, vCPU reset processing is executed as a result of an APIC INIT
event, this time with all of the guest CPUID information set, resulting
in TSC_AUX virtualization being enabled, but only for the APs. The BSP
always sees a TSC_AUX value of 0 which probably went unnoticed because,
at least for Linux, the BSP TSC_AUX value is 0.

Move the TSC_AUX virtualization enablement out of the init_vmcb() path and
into the vcpu_after_set_cpuid() path to allow for proper initialization of
the support after the guest CPUID information has been set.

With the TSC_AUX virtualization support now in the vcpu_set_after_cpuid()
path, the intercepts must be either cleared or set based on the guest
CPUID input.

Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <4137fbcb9008951ab5f0befa74a0399d2cce809a.1694811272.git.thomas.lendacky@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: SVM: INTERCEPT_RDTSCP is never intercepted anyway

svm_recalc_instruction_intercepts() is always called at least once
before the vCPU is started, so the setting or clearing of the RDTSCP
intercept can be dropped from the TSC_AUX virtualization support.

Extracted from a patch by Tom Lendacky.

Cc: stable@vger.kernel.org
Fixes: 296d5a17e793 ("KVM: SEV-ES: Use V_TSC_AUX if available instead of RDTSC/MSR_TSC_AUX intercepts")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Stop zapping invalidated TDP MMU roots asynchronously

Stop zapping invalidate TDP MMU roots via work queue now that KVM
preserves TDP MMU roots until they are explicitly invalidated.  Zapping
roots asynchronously was effectively a workaround to avoid stalling a vCPU
for an extended during if a vCPU unloaded a root, which at the time
happened whenever the guest toggled CR0.WP (a frequent operation for some
guest kernels).

While a clever hack, zapping roots via an unbound worker had subtle,
unintended consequences on host scheduling, especially when zapping
multiple roots, e.g. as part of a memslot.  Because the work of zapping a
root is no longer bound to the task that initiated the zap, things like
the CPU affinity and priority of the original task get lost.  Losing the
affinity and priority can be especially problematic if unbound workqueues
aren't affined to a small number of CPUs, as zapping multiple roots can
cause KVM to heavily utilize the majority of CPUs in the system, *beyond*
the CPUs KVM is already using to run vCPUs.

When deleting a memslot via KVM_SET_USER_MEMORY_REGION, the async root
zap can result in KVM occupying all logical CPUs for ~8ms, and result in
high priority tasks not being scheduled in in a timely manner.  In v5.15,
which doesn't preserve unloaded roots, the issues were even more noticeable
as KVM would zap roots more frequently and could occupy all CPUs for 50ms+.

Consuming all CPUs for an extended duration can lead to significant jitter
throughout the system, e.g. on ChromeOS with virtio-gpu, deleting memslots
is a semi-frequent operation as memslots are deleted and recreated with
different host virtual addresses to react to host GPU drivers allocating
and freeing GPU blobs.  On ChromeOS, the jitter manifests as audio blips
during games due to the audio server's tasks not getting scheduled in
promptly, despite the tasks having a high realtime priority.

Deleting memslots isn't exactly a fast path and should be avoided when
possible, and ChromeOS is working towards utilizing MAP_FIXED to avoid the
memslot shenanigans, but KVM is squarely in the wrong.  Not to mention
that removing the async zapping eliminates a non-trivial amount of
complexity.

Note, one of the subtle behaviors hidden behind the async zapping is that
KVM would zap invalidated roots only once (ignoring partial zaps from
things like mmu_notifier events).  Preserve this behavior by adding a flag
to identify roots that are scheduled to be zapped versus roots that have
already been zapped but not yet freed.

Add a comment calling out why kvm_tdp_mmu_invalidate_all_roots() can
encounter invalid roots, as it's not at all obvious why zapping
invalidated roots shouldn't simply zap all invalid roots.

Reported-by: Pattara Teerapong <pteerapong@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Yiwei Zhang<zzyiwei@google.com>
Cc: Paul Hsia <paulhsia@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230916003916.2545000-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: x86/mmu: Do not filter address spaces in for_each_tdp_mmu_root_yield_safe()

All callers except the MMU notifier want to process all address spaces.
Remove the address space ID argument of for_each_tdp_mmu_root_yield_safe()
and switch the MMU notifier to use __for_each_tdp_mmu_root_yield_safe().

Extracted out of a patch by Sean Christopherson <seanjc@google.com>

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'hardening-v6.6-rc3' of git://git./linux/kernel/git/kees/linux

Pull hardening fixes from Kees Cook:

 - Fix UAPI stddef.h to avoid C++-ism (Alexey Dobriyan)

 - Fix harmless UAPI stddef.h header guard endif (Alexey Dobriyan)

* tag 'hardening-v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  uapi: stddef.h: Fix __DECLARE_FLEX_ARRAY for C++
  uapi: stddef.h: Fix header guard location

Merge tag 'xfs-6.6-fixes-1' of git://git./fs/xfs/xfs-linux

Pull xfs fixes from Chandan Babu:

 - Fix an integer overflow bug when processing an fsmap call

 - Fix crash due to CPU hot remove event racing with filesystem mount
   operation

 - During read-only mount, XFS does not allow the contents of the log to
   be recovered when there are one or more unrecognized rcompat features
   in the primary superblock, since the log might have intent items
   which the kernel does not know how to process

 - During recovery of log intent items, XFS now reserves log space
   sufficient for one cycle of a permanent transaction to execute.
   Otherwise, this could lead to livelocks due to non-availability of
   log space

 - On an fs which has an ondisk unlinked inode list, trying to delete a
   file or allocating an O_TMPFILE file can cause the fs to the shutdown
   if the first inode in the ondisk inode list is not present in the
   inode cache. The bug is solved by explicitly loading the first inode
   in the ondisk unlinked inode list into the inode cache if it is not
   already cached

   A similar problem arises when the uncached inode is present in the
   middle of the ondisk unlinked inode list. This second bug is
   triggered when executing operations like quotacheck and bulkstat. In
   this case, XFS now reads in the entire ondisk unlinked inode list

 - Enable LARP mode only on recent v5 filesystems

 - Fix a out of bounds memory access in scrub

 - Fix a performance bug when locating the tail of the log during
   mounting a filesystem

* tag 'xfs-6.6-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: use roundup_pow_of_two instead of ffs during xlog_find_tail
  xfs: only call xchk_stats_merge after validating scrub inputs
  xfs: require a relatively recent V5 filesystem for LARP mode
  xfs: make inode unlinked bucket recovery work with quotacheck
  xfs: load uncached unlinked inodes into memory on demand
  xfs: reserve less log space when recovering log intent items
  xfs: fix log recovery when unknown rocompat bits are set
  xfs: reload entire unlinked bucket lists
  xfs: allow inode inactivation during a ro mount log recovery
  xfs: use i_prev_unlinked to distinguish inodes that are not on the unlinked list
  xfs: remove CPU hotplug infrastructure
  xfs: remove the all-mounts list
  xfs: use per-mount cpumask to track nonempty percpu inodegc lists
  xfs: fix an agbno overflow in __xfs_getfsmap_datadev
  xfs: fix per-cpu CIL structure aggregation racing with dying cpus
  xfs: fix select in config XFS_ONLINE_SCRUB_STATS

cxl/acpi: Annotate struct cxl_cxims_data with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct cxl_cxims_data.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-cxl@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230922175319.work.096-kees@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

cxl/port: Fix cxl_test register enumeration regression

The cxl_test unit test environment models a CXL topology for
sysfs/user-ABI regression testing. It uses interface mocking via the
"--wrap=" linker option to redirect cxl_core routines that parse
hardware registers with versions that just publish objects, like
devm_cxl_enumerate_decoders().

Starting with:

Commit 19ab69a60e3b ("cxl/port: Store the port's Component Register mappings in struct cxl_port")

...port register enumeration is moved into devm_cxl_add_port(). This
conflicts with the "cxl_test avoids emulating registers stance" so
either the port code needs to be refactored (too violent), or modified
so that register enumeration is skipped on "fake" cxl_test ports
(annoying, but straightforward).

This conflict has happened previously and the "check for platform
device" workaround to avoid instrusive refactoring was deployed in those
scenarios. In general, refactoring should only benefit production code,
test code needs to remain minimally instrusive to the greatest extent
possible.

This was missed previously because it may sometimes just cause warning
messages to be emitted, but it can also cause test failures. The
backport to -stable is only nice to have for clean cxl_test runs.

Fixes: 19ab69a60e3b ("cxl/port: Store the port's Component Register mappings in struct cxl_port")
Cc: stable@vger.kernel.org
Reported-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/169476525052.1013896.6235102957693675187.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

eventfs: Remember what dentries were created on dir open

Using the following code with libtracefs:

int dfd;

// create the directory events/kprobes/kp1
tracefs_kprobe_raw(NULL, "kp1", "schedule_timeout", "time=$arg1");

// Open the kprobes directory
dfd = tracefs_instance_file_open(NULL, "events/kprobes", O_RDONLY);

// Do a lookup of the kprobes/kp1 directory (by looking at enable)
tracefs_file_exists(NULL, "events/kprobes/kp1/enable");

// Now create a new entry in the kprobes directory
tracefs_kprobe_raw(NULL, "kp2", "schedule_hrtimeout", "expires=$arg1");

// Do another lookup to create the dentries
tracefs_file_exists(NULL, "events/kprobes/kp2/enable"))

// Close the directory
close(dfd);

What happened above, the first open (dfd) will call
dcache_dir_open_wrapper() that will create the dentries and up their ref
counts.

Now the creation of "kp2" will add another dentry within the kprobes
directory.

Upon the close of dfd, eventfs_release() will now do a dput for all the
entries in kprobes. But this is where the problem lies. The open only
upped the dentry of kp1 and not kp2. Now the close is decrementing both
kp1 and kp2, which causes kp2 to get a negative count.

Doing a "trace-cmd reset" which deletes all the kprobes cause the kernel
to crash! (due to the messed up accounting of the ref counts).

To solve this, save all the dentries that are opened in the
dcache_dir_open_wrapper() into an array, and use this array to know what
dentries to do a dput on in eventfs_release().

Since the dcache_dir_open_wrapper() calls dcache_dir_open() which uses the
file->private_data, we need to also add a wrapper around dcache_readdir()
that uses the cursor assigned to the file->private_data. This is because
the dentries need to also be saved in the file->private_data. To do this
create the structure:

  struct dentry_list {
void *cursor;
struct dentry **dentries;
  };

Which will hold both the cursor and the dentries. Some shuffling around is
needed to make sure that dcache_dir_open() and dcache_readdir() only see
the cursor.

Link: https://lore.kernel.org/linux-trace-kernel/20230919211804.230edf1e@gandalf.local.home/
Link: https://lore.kernel.org/linux-trace-kernel/20230922163446.1431d4fa@gandalf.local.home
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ajay Kaher <akaher@vmware.com>
Fixes: 63940449555e7 ("eventfs: Implement eventfs lookup, read, open functions")
Reported-by: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

ring-buffer: Fix bytes info in per_cpu buffer stats

The 'bytes' info in file 'per_cpu/cpu<X>/stats' means the number of
bytes in cpu buffer that have not been consumed. However, currently
after consuming data by reading file 'trace_pipe', the 'bytes' info
was not changed as expected.

  # cat per_cpu/cpu0/stats
  entries: 0
  overrun: 0
  commit overrun: 0
  bytes: 568             <--- 'bytes' is problematical !!!
  oldest event ts:  8651.371479
  now ts:  8653.912224
  dropped events: 0
  read events: 8

The root cause is incorrect stat on cpu_buffer->read_bytes. To fix it:
  1. When stat 'read_bytes', account consumed event in rb_advance_reader();
  2. When stat 'entries_bytes', exclude the discarded padding event which
     is smaller than minimum size because it is invisible to reader. Then
     use rb_page_commit() instead of BUF_PAGE_SIZE at where accounting for
     page-based read/remove/overrun.

Also correct the comments of ring_buffer_bytes_cpu() in this patch.

Link: https://lore.kernel.org/linux-trace-kernel/20230921125425.1708423-1-zhengyejian1@huawei.com
Cc: stable@vger.kernel.org
Fixes: c64e148a3be3 ("trace: Add ring buffer stats to measure rate of events")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Merge tag 'thermal-6.6-rc3' of git://git./linux/kernel/git/rafael/linux-pm

Pull thermal control fix from Rafael Wysocki:
 "Unbreak the trip point update sysfs interface that has been broken
  since the 6.3 cycle (Rafael Wysocki)"

* tag 'thermal-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  thermal: sysfs: Fix trip_point_hyst_store()

Merge tag 'acpi-6.6-rc3' of git://git./linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "These fix a general ACPI processor driver regression and an ia64 build
  issue, both introduced recently.

  Specifics:

   - Fix recently introduced uninitialized memory access issue in the
     ACPI processor driver (Michal Wilczynski)

   - Fix ia64 build inadvertently broken by recent ACPI processor driver
     changes, which is prudent to do for 6.6 even though ia64 support is
     slated for removal in 6.7 (Ard Biesheuvel)"

* tag 'acpi-6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: processor: Fix uninitialized access of buf in acpi_set_pdc_bits()
  acpi: Provide ia64 dummy implementation of acpi_proc_quirk_mwait_check()

Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Small crop of relatively boring arm64 fixes for -rc3.

  That's not to say we don't have any juicy bugs, however, it's just
  that fixes for those are likely to come via -mm and -tip for a hugetlb
  and an atomics issue respectively. I get left with the
  documentation...

   - Fix detection of "ClearBHB" and "Hinted Conditional Branch" features

   - Fix broken wildcarding for Arm PMU MAINTAINERS entry

   - Add missing documentation for userspace-visible ID register fields"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Document missing userspace visible fields in ID_AA64ISAR2_EL1
  arm64/hbc: Document HWCAP2_HBC
  arm64/sme: Include ID_AA64PFR1_EL1.SME in cpu-feature-registers.rst
  arm64: cpufeature: Fix CLRBHB and BC detection
  MAINTAINERS: Use wildcard pattern for ARM PMU headers

Merge tag 'x86_urgent_for_v6.6-rc3' of git://git./linux/kernel/git/tip/tip

Pull x86 rethunk fixes from Borislav Petkov:
 "Fix the patching ordering between static calls and return thunks"

* tag 'x86_urgent_for_v6.6-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86,static_call: Fix static-call vs return-thunk
  x86/alternatives: Remove faulty optimization