linux.git/arch/m68k/kernel, branch v6.5

m68k: Fix invalid .section syntax

2023-07-24T12:50:02+00:00

gas supports several different forms for .section for ELF targets,
including:
    .section NAME [, "FLAGS"[, @TYPE[,FLAG_SPECIFIC_ARGUMENTS]]]
and:
    .section "NAME"[, #FLAGS...]

In several places we use a mix of these two forms:
    .section NAME, #FLAGS...

A current development snapshot of binutils (2.40.50.20230611) treats
this mixed syntax as an error.

Change to consistently use:
    .section NAME, "FLAGS"
as is used elsewhere in the kernel.

Link: https://buildd.debian.org/status/fetch.php?pkg=linux&arch=m68k&ver=6.4%7Erc6-1%7Eexp1&stamp=1686907300&raw=1
Signed-off-by: Ben Hutchings 
Tested-by: Jan-Benedict Glaw 
Link: https://lore.kernel.org/r/ZIyBaueWT9jnTwRC@decadent.org.uk
Signed-off-by: Geert Uytterhoeven

Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2023-06-28T17:28:11+00:00

Pull mm updates from Andrew Morton:

 - Yosry Ahmed brought back some cgroup v1 stats in OOM logs

 - Yosry has also eliminated cgroup's atomic rstat flushing

 - Nhat Pham adds the new cachestat() syscall. It provides userspace
   with the ability to query pagecache status - a similar concept to
   mincore() but more powerful and with improved usability

 - Mel Gorman provides more optimizations for compaction, reducing the
   prevalence of page rescanning

 - Lorenzo Stoakes has done some maintanance work on the
   get_user_pages() interface

 - Liam Howlett continues with cleanups and maintenance work to the
   maple tree code. Peng Zhang also does some work on maple tree

 - Johannes Weiner has done some cleanup work on the compaction code

 - David Hildenbrand has contributed additional selftests for
   get_user_pages()

 - Thomas Gleixner has contributed some maintenance and optimization
   work for the vmalloc code

 - Baolin Wang has provided some compaction cleanups,

 - SeongJae Park continues maintenance work on the DAMON code

 - Huang Ying has done some maintenance on the swap code's usage of
   device refcounting

 - Christoph Hellwig has some cleanups for the filemap/directio code

 - Ryan Roberts provides two patch series which yield some
   rationalization of the kernel's access to pte entries - use the
   provided APIs rather than open-coding accesses

 - Lorenzo Stoakes has some fixes to the interaction between pagecache
   and directio access to file mappings

 - John Hubbard has a series of fixes to the MM selftesting code

 - ZhangPeng continues the folio conversion campaign

 - Hugh Dickins has been working on the pagetable handling code, mainly
   with a view to reducing the load on the mmap_lock

 - Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
   from 128 to 8

 - Domenico Cerasuolo has improved the zswap reclaim mechanism by
   reorganizing the LRU management

 - Matthew Wilcox provides some fixups to make gfs2 work better with the
   buffer_head code

 - Vishal Moola also has done some folio conversion work

 - Matthew Wilcox has removed the remnants of the pagevec code - their
   functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
  mm/hugetlb: remove hugetlb_set_page_subpool()
  mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
  hugetlb: revert use of page_cache_next_miss()
  Revert "page cache: fix page_cache_next/prev_miss off by one"
  mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
  mm: memcg: rename and document global_reclaim()
  mm: kill [add|del]_page_to_lru_list()
  mm: compaction: convert to use a folio in isolate_migratepages_block()
  mm: zswap: fix double invalidate with exclusive loads
  mm: remove unnecessary pagevec includes
  mm: remove references to pagevec
  mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
  mm: remove struct pagevec
  net: convert sunrpc from pagevec to folio_batch
  i915: convert i915_gpu_error to use a folio_batch
  pagevec: rename fbatch_count()
  mm: remove check_move_unevictable_pages()
  drm: convert drm_gem_put_pages() to use a folio_batch
  i915: convert shmem_sg_free_table() to use a folio_batch
  scatterlist: add sg_set_folio()
  ...

Merge tag 'x86-boot-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-06-26T20:39:10+00:00

Pull x86 boot updates from Thomas Gleixner:
 "Initialize FPU late.

  Right now FPU is initialized very early during boot. There is no real
  requirement to do so. The only requirement is to have it done before
  alternatives are patched.

  That's done in check_bugs() which does way more than what the function
  name suggests.

  So first rename check_bugs() to arch_cpu_finalize_init() which makes
  it clear what this is about.

  Move the invocation of arch_cpu_finalize_init() earlier in
  start_kernel() as it has to be done before fork_init() which needs to
  know the FPU register buffer size.

  With those prerequisites the FPU initialization can be moved into
  arch_cpu_finalize_init(), which removes it from the early and fragile
  part of the x86 bringup"

* tag 'x86-boot-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mem_encrypt: Unbreak the AMD_MEM_ENCRYPT=n build
  x86/fpu: Move FPU initialization into arch_cpu_finalize_init()
  x86/fpu: Mark init functions __init
  x86/fpu: Remove cpuinfo argument from init functions
  x86/init: Initialize signal frame size late
  init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init()
  init: Invoke arch_cpu_finalize_init() earlier
  init: Remove check_bugs() leftovers
  um/cpu: Switch to arch_cpu_finalize_init()
  sparc/cpu: Switch to arch_cpu_finalize_init()
  sh/cpu: Switch to arch_cpu_finalize_init()
  mips/cpu: Switch to arch_cpu_finalize_init()
  m68k/cpu: Switch to arch_cpu_finalize_init()
  loongarch/cpu: Switch to arch_cpu_finalize_init()
  ia64/cpu: Switch to arch_cpu_finalize_init()
  ARM: cpu: Switch to arch_cpu_finalize_init()
  x86/cpu: Switch to arch_cpu_finalize_init()
  init: Provide arch_cpu_finalize_init()

m68k: allow pte_offset_map[_lock]() to fail

2023-06-19T23:19:06+00:00

In rare transient cases, not yet made possible, pte_offset_map() and
pte_offset_map_lock() may not find a page table: handle appropriately.

Restructure cf_tlb_miss() with a pte_unmap() (previously omitted)
at label out, followed by one local_irq_restore() for all.

Link: https://lkml.kernel.org/r/795f6a7-bcca-cdf-ad2a-fbdaa232998c@google.com
Signed-off-by: Hugh Dickins 
Cc: Alexander Gordeev 
Cc: Alexandre Ghiti 
Cc: Aneesh Kumar K.V 
Cc: Catalin Marinas 
Cc: Christian Borntraeger 
Cc: Chris Zankel 
Cc: Claudio Imbrenda 
Cc: David Hildenbrand 
Cc: "David S. Miller" 
Cc: Geert Uytterhoeven 
Cc: Greg Ungerer 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: John David Anglin 
Cc: John Paul Adrian Glaubitz 
Cc: Kirill A. Shutemov 
Cc: Matthew Wilcox (Oracle) 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Mike Kravetz 
Cc: Mike Rapoport (IBM) 
Cc: Palmer Dabbelt 
Cc: Peter Zijlstra 
Cc: Qi Zheng 
Cc: Russell King 
Cc: Suren Baghdasaryan 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Signed-off-by: Andrew Morton

m68k/cpu: Switch to arch_cpu_finalize_init()

2023-06-16T08:15:59+00:00

check_bugs() is about to be phased out. Switch over to the new
arch_cpu_finalize_init() implementation.

No functional change.

Signed-off-by: Thomas Gleixner 
Acked-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/20230613224545.254342916@linutronix.de

cachestat: wire up cachestat for other architectures

2023-06-09T23:25:16+00:00

cachestat is previously only wired in for x86 (and architectures using
the generic unistd.h table):

https://lore.kernel.org/lkml/20230503013608.2431726-1-nphamcs@gmail.com/

This patch wires cachestat in for all the other architectures.

[nphamcs@gmail.com: wire up cachestat for arm64]
  Link: https://lkml.kernel.org/r/20230511092843.3896327-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20230510195806.2902878-1-nphamcs@gmail.com
Signed-off-by: Nhat Pham 
Tested-by: Michael Ellerman 	[powerpc]
Acked-by: Geert Uytterhoeven 	[m68k]
Reviewed-by: Arnd Bergmann 
Acked-by: Heiko Carstens 		[s390]
Cc: Alexander Gordeev 
Cc: Christian Borntraeger 
Cc: Christophe Leroy 
Cc: Chris Zankel 
Cc: David S. Miller 
Cc: Helge Deller 
Cc: Ivan Kokshaysky 
Cc: "James E.J. Bottomley" 
Cc: Johannes Weiner 
Cc: John Paul Adrian Glaubitz 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michal Simek 
Cc: Nicholas Piggin 
Cc: Richard Henderson 
Cc: Rich Felker 
Cc: Russell King 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Vasily Gorbik 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

m68k: Move signal frame following exception on 68020/030

2023-05-22T11:51:20+00:00

On 68030/020, an instruction such as, moveml %a2-%a3/%a5,%sp@- may cause
a stack page fault during instruction execution (i.e. not at an
instruction boundary) and produce a format 0xB exception frame.

In this situation, the value of USP will be unreliable.  If a signal is
to be delivered following the exception, this USP value is used to
calculate the location for a signal frame.  This can result in a
corrupted user stack.

The corruption was detected in dash (actually in glibc) where it showed
up as an intermittent "stack smashing detected" message and crash
following signal delivery for SIGCHLD.

It was hard to reproduce that failure because delivery of the signal
raced with the page fault and because the kernel places an unpredictable
gap of up to 7 bytes between the USP and the signal frame.

A format 0xB exception frame can be produced by a bus error or an
address error.  The 68030 Users Manual says that address errors occur
immediately upon detection during instruction prefetch.  The instruction
pipeline allows prefetch to overlap with other instructions, which means
an address error can arise during the execution of a different
instruction.  So it seems likely that this patch may help in the address
error case also.

Reported-and-tested-by: Stan Johnson 
Link: https://lore.kernel.org/all/CAMuHMdW3yD22_ApemzW_6me3adq6A458u1_F0v-1EYwK_62jPA@mail.gmail.com/
Cc: Michael Schmitz 
Cc: Andreas Schwab 
Cc: stable@vger.kernel.org
Co-developed-by: Michael Schmitz 
Signed-off-by: Michael Schmitz 
Signed-off-by: Finn Thain 
Reviewed-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/9e66262a754fcba50208aa424188896cc52a1dd1.1683365892.git.fthain@linux-m68k.org
Signed-off-by: Geert Uytterhoeven

m68k: kexec: Include

2023-04-21T07:53:54+00:00

Include reboot.h in machine_kexec.c for declaration of
machine_crash_shutdown and machine_shutdown.

gcc-12 with W=1 reports:

 arch/m68k/kernel/machine_kexec.c:26:6: warning: no previous prototype for 'machine_shutdown' [-Wmissing-prototypes]
    26 | void machine_shutdown(void)
       |      ^~~~~~~~~~~~~~~~
 arch/m68k/kernel/machine_kexec.c:30:6: warning: no previous prototype for 'machine_crash_shutdown' [-Wmissing-prototypes]
    30 | void machine_crash_shutdown(struct pt_regs *regs)
       |      ^~~~~~~~~~~~~~~~~~~~~~

No functional changes intended.
Compile tested only.

Signed-off-by: Simon Horman 
Reviewed-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/20230421-m68k-kexec-include-reboot-v1-1-7552963a0f25@kernel.org
Signed-off-by: Geert Uytterhoeven

m68k: Only force 030 bus error if PC not in exception table

2023-03-06T13:09:42+00:00

__get_kernel_nofault() does copy data in supervisor mode when
forcing a task backtrace log through /proc/sysrq_trigger.
This is expected cause a bus error exception on e.g. NULL
pointer dereferencing when logging a kernel task has no
workqueue associated. This bus error ought to be ignored.

Our 030 bus error handler is ill equipped to deal with this:

Whenever ssw indicates a kernel mode access on a data fault,
we don't even attempt to handle the fault and instead always
send a SEGV signal (or panic). As a result, the check
for exception handling at the fault PC (buried in
send_sig_fault() which gets called from do_page_fault()
eventually) is never used.

In contrast, both 040 and 060 access error handlers do not
care whether a fault happened on supervisor mode access,
and will call do_page_fault() on those, ultimately honoring
the exception table.

Add a check in bus_error030 to call do_page_fault() in case
we do have an entry for the fault PC in our exception table.

I had attempted a fix for this earlier in 2019 that did rely
on testing pagefault_disabled() (see link below) to achieve
the same thing, but this patch should be more generic.

Tested on 030 Atari Falcon.

Reported-by: Eero Tamminen 
Link: https://lore.kernel.org/r/alpine.LNX.2.21.1904091023540.25@nippy.intranet
Link: https://lore.kernel.org/r/63130691-1984-c423-c1f2-73bfd8d3dcd3@gmail.com
Signed-off-by: Michael Schmitz 
Reviewed-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/20230301021107.26307-1-schmitzmic@gmail.com
Signed-off-by: Geert Uytterhoeven

m68k: mm: Move initrd phys_to_virt handling after paging_init()

2023-03-06T13:09:42+00:00

When booting with an initial ramdisk on platforms where physical memory
does not start at address zero (e.g. on Amiga):

    initrd: 0ef0602c - 0f800000
    Zone ranges:
      DMA      [mem 0x0000000008000000-0x000000f7ffffffff]
      Normal   empty
    Movable zone start for each node
    Early memory node ranges
      node   0: [mem 0x0000000008000000-0x000000000f7fffff]
    Initmem setup node 0 [mem 0x0000000008000000-0x000000000f7fffff]
    Unable to handle kernel access at virtual address (ptrval)
    Oops: 00000000
    Modules linked in:
    PC: [<00201d3c>] memcmp+0x28/0x56

As phys_to_virt() relies on m68k_memoffset and module_fixup(), it must
not be called before paging_init().  Hence postpone the phys_to_virt
handling for the initial ramdisk until after calling paging_init().

While at it, reduce #ifdef clutter by using IS_ENABLED() instead.

Fixes: 376e3fdecb0dcae2 ("m68k: Enable memtest functionality")
Reported-by: Stephen Walsh 
Link: https://lists.debian.org/debian-68k/2022/09/msg00007.html
Reported-by: John Paul Adrian Glaubitz 
Link: https://lore.kernel.org/r/4f45f05f377bf3f5baf88dbd5c3c8aeac59d94f0.camel@physik.fu-berlin.de
Signed-off-by: Geert Uytterhoeven 
Acked-by: Finn Thain 
Link: https://lore.kernel.org/r/dff216da09ab7a60217c3fc2147e671ae07d636f.1677528627.git.geert@linux-m68k.org