linux-toradex.git/arch/xtensa/mm, branch v6.7

xtensa: tlb: include for missing prototype

2023-09-20T12:03:21+00:00

Add the prototype for check_tlb_sanity() to  and use that
header to prevent a build warning:

arch/xtensa/mm/tlb.c:273:6: warning: no previous prototype for 'check_tlb_sanity' [-Wmissing-prototypes]
  273 | void check_tlb_sanity(void)

Signed-off-by: Randy Dunlap 
Cc: Chris Zankel 
Cc: Max Filippov 
Message-Id: <20230920052139.10570-13-rdunlap@infradead.org>
Signed-off-by: Max Filippov

xtensa: fault: include

2023-09-20T12:03:18+00:00

Use  to provide the function prototype for do_page_fault()
to prevent a build warning:

arch/xtensa/mm/fault.c:87:6: warning: no previous prototype for 'do_page_fault' [-Wmissing-prototypes]
   87 | void do_page_fault(struct pt_regs *regs)

Signed-off-by: Randy Dunlap 
Cc: Chris Zankel 
Cc: Max Filippov 
Message-Id: <20230920052139.10570-3-rdunlap@infradead.org>
Signed-off-by: Max Filippov

xtensa: implement the new page table range API

2023-08-24T23:20:24+00:00

Add PFN_PTE_SHIFT, update_mmu_cache_range(), flush_dcache_folio() and
flush_icache_pages().

Link: https://lkml.kernel.org/r/20230802151406.3735276-30-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Acked-by: Mike Rapoport (IBM) 
Cc: Max Filippov 
Signed-off-by: Andrew Morton

xtensa: mm: convert to GENERIC_IOREMAP

2023-08-18T17:12:35+00:00

By taking GENERIC_IOREMAP method, the generic generic_ioremap_prot(),
generic_iounmap(), and their generic wrapper ioremap_prot(), ioremap() and
iounmap() are all visible and available to arch.  Arch needs to provide
wrapper functions to override the generic versions if there's arch
specific handling in its ioremap_prot(), ioremap() or iounmap().  This
change will simplify implementation by removing duplicated code with
generic_ioremap_prot() and generic_iounmap(), and has the equivalent
functioality as before.

Here, add wrapper functions ioremap_prot(), ioremap() and iounmap() for
xtensa's special operation when ioremap() and iounmap().

Link: https://lkml.kernel.org/r/20230706154520.11257-14-bhe@redhat.com
Signed-off-by: Baoquan He 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Mike Rapoport (IBM) 
Cc: Chris Zankel 
Cc: Max Filippov 
Cc: Alexander Gordeev 
Cc: Arnd Bergmann 
Cc: Brian Cain 
Cc: Catalin Marinas 
Cc: Christian Borntraeger 
Cc: Christophe Leroy 
Cc: David Laight 
Cc: Geert Uytterhoeven 
Cc: Gerald Schaefer 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: "James E.J. Bottomley" 
Cc: John Paul Adrian Glaubitz 
Cc: Jonas Bonn 
Cc: Kefeng Wang 
Cc: Matthew Wilcox 
Cc: Michael Ellerman 
Cc: Nathan Chancellor 
Cc: Nicholas Piggin 
Cc: Niklas Schnelle 
Cc: Rich Felker 
Cc: Stafford Horne 
Cc: Stefan Kristiansson 
Cc: Sven Schnelle 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

Merge branch 'expand-stack'

2023-06-29T03:35:21+00:00

This modifies our user mode stack expansion code to always take the
mmap_lock for writing before modifying the VM layout.

It's actually something we always technically should have done, but
because we didn't strictly need it, we were being lazy ("opportunistic"
sounds so much better, doesn't it?) about things, and had this hack in
place where we would extend the stack vma in-place without doing the
proper locking.

And it worked fine.  We just needed to change vm_start (or, in the case
of grow-up stacks, vm_end) and together with some special ad-hoc locking
using the anon_vma lock and the mm->page_table_lock, it all was fairly
straightforward.

That is, it was all fine until Ruihan Li pointed out that now that the
vma layout uses the maple tree code, we *really* don't just change
vm_start and vm_end any more, and the locking really is broken.  Oops.

It's not actually all _that_ horrible to fix this once and for all, and
do proper locking, but it's a bit painful.  We have basically three
different cases of stack expansion, and they all work just a bit
differently:

 - the common and obvious case is the page fault handling. It's actually
   fairly simple and straightforward, except for the fact that we have
   something like 24 different versions of it, and you end up in a maze
   of twisty little passages, all alike.

 - the simplest case is the execve() code that creates a new stack.
   There are no real locking concerns because it's all in a private new
   VM that hasn't been exposed to anybody, but lockdep still can end up
   unhappy if you get it wrong.

 - and finally, we have GUP and page pinning, which shouldn't really be
   expanding the stack in the first place, but in addition to execve()
   we also use it for ptrace(). And debuggers do want to possibly access
   memory under the stack pointer and thus need to be able to expand the
   stack as a special case.

None of these cases are exactly complicated, but the page fault case in
particular is just repeated slightly differently many many times.  And
ia64 in particular has a fairly complicated situation where you can have
both a regular grow-down stack _and_ a special grow-up stack for the
register backing store.

So to make this slightly more manageable, the bulk of this series is to
first create a helper function for the most common page fault case, and
convert all the straightforward architectures to it.

Thus the new 'lock_mm_and_find_vma()' helper function, which ends up
being used by x86, arm, powerpc, mips, riscv, alpha, arc, csky, hexagon,
loongarch, nios2, sh, sparc32, and xtensa.  So we not only convert more
than half the architectures, we now have more shared code and avoid some
of those twisty little passages.

And largely due to this common helper function, the full diffstat of
this series ends up deleting more lines than it adds.

That still leaves eight architectures (ia64, m68k, microblaze, openrisc,
parisc, s390, sparc64 and um) that end up doing 'expand_stack()'
manually because they are doing something slightly different from the
normal pattern.  Along with the couple of special cases in execve() and
GUP.

So there's a couple of patches that first create 'locked' helper
versions of the stack expansion functions, so that there's a obvious
path forward in the conversion.  The execve() case is then actually
pretty simple, and is a nice cleanup from our old "grow-up stackls are
special, because at execve time even they grow down".

The #ifdef CONFIG_STACK_GROWSUP in that code just goes away, because
it's just more straightforward to write out the stack expansion there
manually, instead od having get_user_pages_remote() do it for us in some
situations but not others and have to worry about locking rules for GUP.

And the final step is then to just convert the remaining odd cases to a
new world order where 'expand_stack()' is called with the mmap_lock held
for reading, but where it might drop it and upgrade it to a write, only
to return with it held for reading (in the success case) or with it
completely dropped (in the failure case).

In the process, we remove all the stack expansion from GUP (where
dropping the lock wouldn't be ok without special rules anyway), and add
it in manually to __access_remote_vm() for ptrace().

Thanks to Adrian Glaubitz and Frank Scheiner who tested the ia64 cases.
Everything else here felt pretty straightforward, but the ia64 rules for
stack expansion are really quite odd and very different from everything
else.  Also thanks to Vegard Nossum who caught me getting one of those
odd conditions entirely the wrong way around.

Anyway, I think I want to actually move all the stack expansion code to
a whole new file of its own, rather than have it split up between
mm/mmap.c and mm/memory.c, but since this will have to be backported to
the initial maple tree vma introduction anyway, I tried to keep the
patches _fairly_ minimal.

Also, while I don't think it's valid to expand the stack from GUP, the
final patch in here is a "warn if some crazy GUP user wants to try to
expand the stack" patch.  That one will be reverted before the final
release, but it's left to catch any odd cases during the merge window
and release candidates.

Reported-by: Ruihan Li 

* branch 'expand-stack':
  gup: add warning if some caller would seem to want stack expansion
  mm: always expand the stack with the mmap write lock held
  execve: expand new process stack manually ahead of time
  mm: make find_extend_vma() fail if write lock not held
  powerpc/mm: convert coprocessor fault to lock_mm_and_find_vma()
  mm/fault: convert remaining simple cases to lock_mm_and_find_vma()
  arm/mm: Convert to using lock_mm_and_find_vma()
  riscv/mm: Convert to using lock_mm_and_find_vma()
  mips/mm: Convert to using lock_mm_and_find_vma()
  powerpc/mm: Convert to using lock_mm_and_find_vma()
  arm64/mm: Convert to using lock_mm_and_find_vma()
  mm: make the page fault mmap locking killable
  mm: introduce new 'lock_mm_and_find_vma()' page fault helper

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()
  ...

mm/fault: convert remaining simple cases to lock_mm_and_find_vma()

2023-06-24T21:12:58+00:00

This does the simple pattern conversion of alpha, arc, csky, hexagon,
loongarch, nios2, sh, sparc32, and xtensa to the lock_mm_and_find_vma()
helper.  They all have the regular fault handling pattern without odd
special cases.

The remaining architectures all have something that keeps us from a
straightforward conversion: ia64 and parisc have stacks that can grow
both up as well as down (and ia64 has special address region checks).

And m68k, microblaze, openrisc, sparc64, and um end up having extra
rules about only expanding the stack down a limited amount below the
user space stack pointer.  That is something that x86 used to do too
(long long ago), and it probably could just be skipped, but it still
makes the conversion less than trivial.

Note that this conversion was done manually and with the exception of
alpha without any build testing, because I have a fairly limited cross-
building environment.  The cases are all simple, and I went through the
changes several times, but...

Signed-off-by: Linus Torvalds

xtensa: add pte_unmap() to balance pte_offset_map()

2023-06-19T23:19:10+00:00

To keep balance in future, remember to pte_unmap() after a successful
pte_offset_map().  And act as if get_pte_for_vaddr() really needs a map
there, to read the pteval before "unmapping", to be sure page table is
not removed.

Link: https://lkml.kernel.org/r/ab2581eb-daa6-894e-4aa6-97c81de3b8c@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

xtensa: move early_trap_init from kasan_early_init to init_arch

2023-06-14T04:56:27+00:00

There may be other users for the early traps besides KASAN. Move call to
the early_trap_init from kasan_early_init. Protect init_exc_table
initializer with ifdef to make sure it builds on noMMU configurations.

Signed-off-by: Max Filippov

xtensa: add asm-prototypes.h

2023-06-13T02:48:57+00:00

Move assembly source prototypes from xtensa_ksyms.c to
asm/asm-prototypes.h, move corresponding EXPORT_SYMBOLs to the assembly
sources and enable HAVE_ASM_MODVERSIONS for xtensa.

Signed-off-by: Max Filippov