Pull ptrace_stop cleanups from Eric Biederman:
 "While looking at the ptrace problems with PREEMPT_RT and the problems
  Peter Zijlstra was encountering with ptrace in his freezer rewrite I
  identified some cleanups to ptrace_stop that make sense on their own
  and move make resolving the other problems much simpler.

  The biggest issue is the habit of the ptrace code to change
  task->__state from the tracer to suppress TASK_WAKEKILL from waking up
  the tracee. No other code in the kernel does that and it is straight
  forward to update signal_wake_up and friends to make that unnecessary.

  Peter's task freezer sets frozen tasks to a new state TASK_FROZEN and
  then it stores them by calling "wake_up_state(t, TASK_FROZEN)" relying
  on the fact that all stopped states except the special stop states can
  tolerate spurious wake up and recover their state.

  The state of stopped and traced tasked is changed to be stored in
  task->jobctl as well as in task->__state. This makes it possible for
  the freezer to recover tasks in these special states, as well as
  serving as a general cleanup. With a little more work in that
  direction I believe TASK_STOPPED can learn to tolerate spurious wake
  ups and become an ordinary stop state.

  The TASK_TRACED state has to remain a special state as the registers
  for a process are only reliably available when the process is stopped
  in the scheduler. Fundamentally ptrace needs acess to the saved
  register values of a task.

  There are bunch of semi-random ptrace related cleanups that were found
  while looking at these issues.

  One cleanup that deserves to be called out is from commit 57b6de08b5f6
  ("ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs"). This
  makes a change that is technically user space visible, in the handling
  of what happens to a tracee when a tracer dies unexpectedly. According
  to our testing and our understanding of userspace nothing cares that
  spurious SIGTRAPs can be generated in that case"

* tag 'ptrace_stop-cleanup-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sched,signal,ptrace: Rework TASK_TRACED, TASK_STOPPED state
  ptrace: Always take siglock in ptrace_resume
  ptrace: Don't change __state
  ptrace: Admit ptrace_stop can generate spuriuos SIGTRAPs
  ptrace: Document that wait_task_inactive can't fail
  ptrace: Reimplement PTRACE_KILL by always sending SIGKILL
  signal: Use lockdep_assert_held instead of assert_spin_locked
  ptrace: Remove arch_ptrace_attach
  ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP
  ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP
  signal: Replace __group_send_sig_info with send_signal_locked
  signal: Rename send_signal send_signal_locked

Pull MM updates from Andrew Morton:
 "Almost all of MM here. A few things are still getting finished off,
  reviewed, etc.

   - Yang Shi has improved the behaviour of khugepaged collapsing of
     readonly file-backed transparent hugepages.

   - Johannes Weiner has arranged for zswap memory use to be tracked and
     managed on a per-cgroup basis.

   - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
     runtime enablement of the recent huge page vmemmap optimization
     feature.

   - Baolin Wang contributes a series to fix some issues around hugetlb
     pagetable invalidation.

   - Zhenwei Pi has fixed some interactions between hwpoisoned pages and
     virtualization.

   - Tong Tiangen has enabled the use of the presently x86-only
     page_table_check debugging feature on arm64 and riscv.

   - David Vernet has done some fixup work on the memcg selftests.

   - Peter Xu has taught userfaultfd to handle write protection faults
     against shmem- and hugetlbfs-backed files.

   - More DAMON development from SeongJae Park - adding online tuning of
     the feature and support for monitoring of fixed virtual address
     ranges. Also easier discovery of which monitoring operations are
     available.

   - Nadav Amit has done some optimization of TLB flushing during
     mprotect().

   - Neil Brown continues to labor away at improving our swap-over-NFS
     support.

   - David Hildenbrand has some fixes to anon page COWing versus
     get_user_pages().

   - Peng Liu fixed some errors in the core hugetlb code.

   - Joao Martins has reduced the amount of memory consumed by
     device-dax's compound devmaps.

   - Some cleanups of the arch-specific pagemap code from Anshuman
     Khandual.

   - Muchun Song has found and fixed some errors in the TLB flushing of
     transparent hugepages.

   - Roman Gushchin has done more work on the memcg selftests.

  ... and, of course, many smaller fixes and cleanups. Notably, the
  customary million cleanup serieses from Miaohe Lin"

* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
  mm: kfence: use PAGE_ALIGNED helper
  selftests: vm: add the "settings" file with timeout variable
  selftests: vm: add "test_hmm.sh" to TEST_FILES
  selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
  selftests: vm: add migration to the .gitignore
  selftests/vm/pkeys: fix typo in comment
  ksm: fix typo in comment
  selftests: vm: add process_mrelease tests
  Revert "mm/vmscan: never demote for memcg reclaim"
  mm/kfence: print disabling or re-enabling message
  include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
  include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
  mm: fix a potential infinite loop in start_isolate_page_range()
  MAINTAINERS: add Muchun as co-maintainer for HugeTLB
  zram: fix Kconfig dependency warning
  mm/shmem: fix shmem folio swapoff hang
  cgroup: fix an error handling path in alloc_pagecache_max_30M()
  mm: damon: use HPAGE_PMD_SIZE
  tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
  nodemask.h: fix compilation error with GCC12
  ...

Pull dma-mapping updates from Christoph Hellwig:

 - don't over-decrypt memory (Robin Murphy)

 - takes min align mask into account for the swiotlb max mapping size
   (Tianyu Lan)

 - use GFP_ATOMIC in dma-debug (Mikulas Patocka)

 - fix DMA_ATTR_NO_KERNEL_MAPPING on xen/arm (me)

 - don't fail on highmem CMA pages in dma_direct_alloc_pages (me)

 - cleanup swiotlb initialization and share more code with swiotlb-xen
   (me, Stefano Stabellini)

* tag 'dma-mapping-5.19-2022-05-25' of git://git.infradead.org/users/hch/dma-mapping: (23 commits)
  dma-direct: don't over-decrypt memory
  swiotlb: max mapping size takes min align mask into account
  swiotlb: use the right nslabs-derived sizes in swiotlb_init_late
  swiotlb: use the right nslabs value in swiotlb_init_remap
  swiotlb: don't panic when the swiotlb buffer can't be allocated
  dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMIC
  dma-direct: don't fail on highmem CMA pages in dma_direct_alloc_pages
  swiotlb-xen: fix DMA_ATTR_NO_KERNEL_MAPPING on arm
  x86: remove cruft from <asm/dma-mapping.h>
  swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl
  swiotlb: merge swiotlb-xen initialization into swiotlb
  swiotlb: provide swiotlb_init variants that remap the buffer
  swiotlb: pass a gfp_mask argument to swiotlb_init_late
  swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction
  swiotlb: make the swiotlb_init interface more useful
  x86: centralize setting SWIOTLB_FORCE when guest memory encryption is enabled
  x86: remove the IOMMU table infrastructure
  MIPS/octeon: use swiotlb_init instead of open coding it
  arm/xen: don't check for xen_initial_domain() in xen_create_contiguous_region
  swiotlb: rename swiotlb_late_init_with_default_size
  ...

Patch series "Fix CONT-PTE/PMD size hugetlb issue when unmapping or migrating", v4.

presently, migrating a hugetlb page or unmapping a poisoned hugetlb page,
we'll use ptep_clear_flush() and set_pte_at() to nuke the page table entry
and remap it, and this is incorrect for CONT-PTE or CONT-PMD size hugetlb
page, which will cause potential data consistent issue.  This patch set
will change to use hugetlb related APIs to fix this issue.

Note: Mike pointed out the huge_ptep_get() will only return the one
specific value, and it would not take into account the dirty or young bits
of CONT-PTE/PMDs like the huge_ptep_get_and_clear() [1].  This
inconsistent issue is not introduced by this patch set, and this issue
will be addressed in another thread [2].  Meanwhile the uffd for hugetlb
case [3] pointed out by Gerald also needs another patch to address.

[1] https://lore.kernel.org/linux-mm/85bd80b4-b4fd-0d3f-a2e5-149559f2f387@oracle.com/
[2] https://lore.kernel.org/all/cover.1651998586.git.baolin.wang@linux.alibaba.com/
[3] https://lore.kernel.org/linux-mm/20220503120343.6264e126@thinkpad/


This patch (of 3):

It is incorrect to use ptep_clear_flush() to nuke a hugetlb page table
when unmapping or migrating a hugetlb page, and will change to use
huge_ptep_clear_flush() instead in the following patches.

So this is a preparation patch, which changes the huge_ptep_clear_flush()
to return the original pte to help to nuke a hugetlb page table.

[baolin.wang@linux.alibaba.com: fix build in several more architectures]
  Link: https://lkml.kernel.org/r/0009a4cd-2826-e8be-e671-f050d4f18d5d@linux.alibaba.com
[sfr@canb.auug.org.au: fixup]
  Link: https://lkml.kernel.org/r/20220511181531.7f27a5c1@canb.auug.org.au
Link: https://lkml.kernel.org/r/cover.1652270205.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/20f77ddab90baa249bd24504c413189b82acde69.1652270205.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/cover.1652147571.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/dcf065868cce35bceaf138613ad27f17bb7c0c19.1652147571.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Itanium defines a get_cycles() function, but it does not do the usual
`#define get_cycles get_cycles` dance, making it impossible for generic
code to see if an arch-specific function was defined. While the
get_cycles() ifdef is not currently used, the following timekeeping
patch in this series will depend on the macro existing (or not existing)
when defining random_get_entropy().

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

The last remaining implementation of arch_ptrace_attach is ia64's
ptrace_attach_sync_user_rbs which was added at the end of 2007 in
commit aa91a2e90044 ("[IA64] Synchronize RBS on PTRACE_ATTACH").

Reading the comments and examining the code ptrace_attach_sync_user_rbs
has the sole purpose of saving registers to the stack when ptrace_attach
changes TASK_STOPPED to TASK_TRACED.  In all other cases arch_ptrace_stop
takes care of the register saving.

In commit d79fdd6d96f4 ("ptrace: Clean transitions between TASK_STOPPED and TRACED")
modified ptrace_attach to wake up the thread and enter ptrace_stop normally even
when the thread starts out stopped.

This makes ptrace_attach_sync_user_rbs completely unnecessary.  So just
remove it.

I read through the code to verify that ptrace_attach_sync_user_rbs is
unnecessary.  What I found is that the code is quite dead.

Reading ptrace_attach_sync_user_rbs it is easy to see that the it does
nothing unless __state == TASK_STOPPED.

Calling arch_ptrace_attach (aka ptrace_attach_sync_user_rbs) after
ptrace_traceme it is easy to see that because we are talking about the
current process the value of __state is TASK_RUNNING.  Which means
ptrace_attach_sync_user_rbs does nothing.

The only other call of arch_ptrace_attach (aka
ptrace_attach_sync_user_rbs) is after ptrace_attach.

If the task is running (and PTRACE_SEIZE is not specified), a SIGSTOP
is sent which results in do_signal_stop setting JOBCTL_TRAP_STOP on
the target task (as it is ptraced) and the target task stopping
in ptrace_stop with __state == TASK_TRACED.

If the task was already stopped then ptrace_attach sets
JOBCTL_TRAPPING and JOBCTL_TRAP_STOP, wakes it out of __TASK_STOPPED,
and waits until the JOBCTL_TRAPPING_BIT is clear.  At which point
the task stops in ptrace_stop.

In both cases there are a couple of funning excpetions such as if the
traced task receiveds a SIGCONT, or is set a fatal signal.

However in all of those cases the tracee never stops in __state
TASK_STOPPED.  Which is a long way of saying that ptrace_attach_sync_user_rbs
is guaranteed never to do anything.

Cc: linux-ia64@vger.kernel.org
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20220505182645.497868-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

The IOMMU table tries to separate the different IOMMUs into different
backends, but actually requires various cross calls.

Rewrite the code to do the generic swiotlb/swiotlb-xen setup directly
in pci-dma.c and then just call into the IOMMU drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

Pull vfs updates from Al Viro:
 "Assorted bits and pieces"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: drop needless assignment in aio_read()
  clean overflow checks in count_mounts() a bit
  seq_file: fix NULL pointer arithmetic warning
  uml/x86: use x86 load_unaligned_zeropad()
  asm/user.h: killed unused macros
  constify struct path argument of finish_automount()/do_add_mount()
  fs: Remove FIXME comment in generic_write_checks()

Pull powerpc updates from Michael Ellerman:
 "Livepatch support for 32-bit is probably the standout new feature,
  otherwise mostly just lots of bits and pieces all over the board.

  There's a series of commits cleaning up function descriptor handling,
  which touches a few other arches as well as LKDTM. It has acks from
  Arnd, Kees and Helge.

  Summary:

   - Enforce kernel RO, and implement STRICT_MODULE_RWX for 603.

   - Add support for livepatch to 32-bit.

   - Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS.

   - Merge vdso64 and vdso32 into a single directory.

   - Fix build errors with newer binutils.

   - Add support for UADDR64 relocations, which are emitted by some
     toolchains. This allows powerpc to build with the latest lld.

   - Fix (another) potential userspace r13 corruption in transactional
     memory handling.

   - Cleanups of function descriptor handling & related fixes to LKDTM.

  Thanks to Abdul Haleem, Alexey Kardashevskiy, Anders Roxell, Aneesh
  Kumar K.V, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Bhaskar
  Chowdhury, Cédric Le Goater, Chen Jingwen, Christophe JAILLET,
  Christophe Leroy, Corentin Labbe, Daniel Axtens, Daniel Henrique
  Barboza, David Dai, Fabiano Rosas, Ganesh Goudar, Guo Zhengkui, Hangyu
  Hua, Haren Myneni, Hari Bathini, Igor Zhbanov, Jakob Koschel, Jason
  Wang, Jeremy Kerr, Joachim Wiberg, Jordan Niethe, Julia Lawall, Kajol
  Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mamatha Inamdar,
  Maxime Bizon, Maxim Kiselev, Maxim Kochetkov, Michal Suchanek,
  Nageswara R Sastry, Nathan Lynch, Naveen N. Rao, Nicholas Piggin,
  Nour-eddine Taleb, Paul Menzel, Ping Fang, Pratik R. Sampat, Randy
  Dunlap, Ritesh Harjani, Rohan McLure, Russell Currey, Sachin Sant,
  Segher Boessenkool, Shivaprasad G Bhat, Sourabh Jain, Thierry Reding,
  Tobias Waldekranz, Tyrel Datwyler, Vaibhav Jain, Vladimir Oltean,
  Wedson Almeida Filho, and YueHaibing"

* tag 'powerpc-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
  powerpc/pseries: Fix use after free in remove_phb_dynamic()
  powerpc/time: improve decrementer clockevent processing
  powerpc/time: Fix KVM host re-arming a timer beyond decrementer range
  powerpc/tm: Fix more userspace r13 corruption
  powerpc/xive: fix return value of __setup handler
  powerpc/64: Add UADDR64 relocation support
  powerpc: 8xx: fix a return value error in mpc8xx_pic_init
  powerpc/ps3: remove unneeded semicolons
  powerpc/64: Force inlining of prevent_user_access() and set_kuap()
  powerpc/bitops: Force inlining of fls()
  powerpc: declare unmodified attribute_group usages const
  powerpc/spufs: Fix build warning when CONFIG_PROC_FS=n
  powerpc/secvar: fix refcount leak in format_show()
  powerpc/64e: Tie PPC_BOOK3E_64 to PPC_FSL_BOOK3E
  powerpc: Move C prototypes out of asm-prototypes.h
  powerpc/kexec: Declare kexec_paca static
  powerpc/smp: Declare current_set static
  powerpc: Cleanup asm-prototypes.c
  powerpc/ftrace: Use STK_GOT in ftrace_mprofile.S
  powerpc/ftrace: Regroup PPC64 specific operations in ftrace_mprofile.S
  ...

Pull flexible-array transformations from Gustavo Silva:
 "Treewide patch that replaces zero-length arrays with flexible-array
  members.

  This has been baking in linux-next for a whole development cycle"

* tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  treewide: Replace zero-length arrays with flexible-array members