On arm64, "rodata=full" has been suppored (but not documented) since
commit:

  c55191e96caa9d78 ("arm64: mm: apply r/o permissions of VM areas to its linear alias as well")

As it's necessary to determine the rodata configuration early during
boot, arm64 has an early_param() handler for this, whereas init/main.c
has a __setup() handler which is run later.

Unfortunately, this split meant that since commit:

  f9a40b0890658330 ("init/main.c: return 1 from handled __setup() functions")

... passing "rodata=full" would result in a spurious warning from the
__setup() handler (though RO permissions would be configured
appropriately).

Further, "rodata=full" has been broken since commit:

  0d6ea3ac94ca77c5 ("lib/kstrtox.c: add "false"/"true" support to kstrtobool()")

... which caused strtobool() to parse "full" as false (in addition to
many other values not documented for the "rodata=" kernel parameter.

This patch fixes this breakage by:

* Moving the core parameter parser to an __early_param(), such that it
  is available early.

* Adding an (optional) arch hook which arm64 can use to parse "full".

* Updating the documentation to mention that "full" is valid for arm64.

* Having the core parameter parser handle "on" and "off" explicitly,
  such that any undocumented values (e.g. typos such as "ful") are
  reported as errors rather than being silently accepted.

Note that __setup() and early_param() have opposite conventions for
their return values, where __setup() uses 1 to indicate a parameter was
handled and early_param() uses 0 to indicate a parameter was handled.

Fixes: f9a40b089065 ("init/main.c: return 1 from handled __setup() functions")
Fixes: 0d6ea3ac94ca ("lib/kstrtox.c: add "false"/"true" support to kstrtobool()")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jagdish Gediya <jvgediya@linux.ibm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20220817154022.3974645-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

Pull x86 fix from Ingo Molnar:
 "Fix the 'IBPB mitigated RETBleed' mode of operation on AMD CPUs (not
  turned on by default), which also need STIBP enabled (if available) to
  be '100% safe' on even the shortest speculation windows"

* tag 'x86-urgent-2022-08-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/bugs: Enable STIBP for IBPB mitigated RETBleed

Pull remaining MM updates from Andrew Morton:
 "Three patch series - two that perform cleanups and one feature:

   - hugetlb_vmemmap cleanups from Muchun Song

   - hardware poisoning support for 1GB hugepages, from Naoya Horiguchi

   - highmem documentation fixups from Fabio De Francesco"

* tag 'mm-stable-2022-08-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits)
  Documentation/mm: add details about kmap_local_page() and preemption
  highmem: delete a sentence from kmap_local_page() kdocs
  Documentation/mm: rrefer kmap_local_page() and avoid kmap()
  Documentation/mm: avoid invalid use of addresses from kmap_local_page()
  Documentation/mm: don't kmap*() pages which can't come from HIGHMEM
  highmem: specify that kmap_local_page() is callable from interrupts
  highmem: remove unneeded spaces in kmap_local_page() kdocs
  mm, hwpoison: enable memory error handling on 1GB hugepage
  mm, hwpoison: skip raw hwpoison page in freeing 1GB hugepage
  mm, hwpoison: make __page_handle_poison returns int
  mm, hwpoison: set PG_hwpoison for busy hugetlb pages
  mm, hwpoison: make unpoison aware of raw error info in hwpoisoned hugepage
  mm, hwpoison, hugetlb: support saving mechanism of raw error pages
  mm/hugetlb: make pud_huge() and follow_huge_pud() aware of non-present pud entry
  mm/hugetlb: check gigantic_page_runtime_supported() in return_unused_surplus_pages()
  mm: hugetlb_vmemmap: use PTRS_PER_PTE instead of PMD_SIZE / PAGE_SIZE
  mm: hugetlb_vmemmap: move code comments to vmemmap_dedup.rst
  mm: hugetlb_vmemmap: improve hugetlb_vmemmap code readability
  mm: hugetlb_vmemmap: replace early_param() with core_param()
  mm: hugetlb_vmemmap: move vmemmap code related to HugeTLB to hugetlb_vmemmap.c
  ...

It it inconvenient to mention the feature of optimizing vmemmap pages
associated with HugeTLB pages when communicating with others since there
is no specific or abbreviated name for it when it is first introduced. 
Let us give it a name HVO (HugeTLB Vmemmap Optimization) from now.

This commit also updates the document about "hugetlb_free_vmemmap" by the
way discussed in thread [1].

Link: https://lore.kernel.org/all/21aae898-d54d-cc4b-a11f-1bb7fddcfffa@redhat.com/ [1]
Link: https://lkml.kernel.org/r/20220628092235.91270-4-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Will Deacon <will@kernel.org>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Pull module updates from Luis Chamberlain:
 "For the 6.0 merge window the modules code shifts to cleanup and minor
  fixes effort. This becomes much easier to do and review now due to the
  code split to its own directory from effort on the last kernel
  release. I expect to see more of this with time and as we expand on
  test coverage in the future. The cleanups and fixes come from usual
  suspects such as Christophe Leroy and Aaron Tomlin but there are also
  some other contributors.

  One particular minor fix worth mentioning is from Helge Deller, where
  he spotted a *forever* incorrect natural alignment on both ELF section
  header tables:

    * .altinstructions
    * __bug_table sections

  A lot of back and forth went on in trying to determine the ill effects
  of this misalignment being present for years and it has been
  determined there should be no real ill effects unless you have a buggy
  exception handler. Helge actually hit one of these buggy exception
  handlers on parisc which is how he ended up spotting this issue. When
  implemented correctly these paths with incorrect misalignment would
  just mean a performance penalty, but given that we are dealing with
  alternatives on modules and with the __bug_table (where info regardign
  BUG()/WARN() file/line information associated with it is stored) this
  really shouldn't be a big deal.

  The only other change with mentioning is the kmap() with
  kmap_local_page() and my only concern with that was on what is done
  after preemption, but the virtual addresses are restored after
  preemption. This is only used on module decompression.

  This all has sit on linux-next for a while except the kmap stuff which
  has been there for 3 weeks"

* tag 'modules-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
  module: Replace kmap() with kmap_local_page()
  module: Show the last unloaded module's taint flag(s)
  module: Use strscpy() for last_unloaded_module
  module: Modify module_flags() to accept show_state argument
  module: Move module's Kconfig items in kernel/module/
  MAINTAINERS: Update file list for module maintainers
  module: Use vzalloc() instead of vmalloc()/memset(0)
  modules: Ensure natural alignment for .altinstructions and __bug_table sections
  module: Increase readability of module_kallsyms_lookup_name()
  module: Fix ERRORs reported by checkpatch.pl
  module: Add support for default value for module async_probe

AMD's "Technical Guidance for Mitigating Branch Type Confusion,
Rev. 1.0 2022-07-12" whitepaper, under section 6.1.2 "IBPB On
Privileged Mode Entry / SMT Safety" says:

  Similar to the Jmp2Ret mitigation, if the code on the sibling thread
  cannot be trusted, software should set STIBP to 1 or disable SMT to
  ensure SMT safety when using this mitigation.

So, like already being done for retbleed=unret, and now also for
retbleed=ibpb, force STIBP on machines that have it, and report its SMT
vulnerability status accordingly.

 [ bp: Remove the "we" and remove "[AMD]" applicability parameter which
   doesn't work here. ]

Fixes: 3ebc17006888 ("x86/bugs: Add retbleed=ibpb")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org # 5.10, 5.15, 5.19
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537
Link: https://lore.kernel.org/r/20220804192201.439596-1-kim.phillips@amd.com

Pull misc updates from Andrew Morton:
 "Updates to various subsystems which I help look after. lib, ocfs2,
  fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
  material this time"

* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  scripts/gdb: ensure the absolute path is generated on initial source
  MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
  mailmap: add linux.dev alias for Brendan Higgins
  mailmap: update Kirill's email
  profile: setup_profiling_timer() is moslty not implemented
  ocfs2: fix a typo in a comment
  ocfs2: use the bitmap API to simplify code
  ocfs2: remove some useless functions
  lib/mpi: fix typo 'the the' in comment
  proc: add some (hopefully) insightful comments
  bdi: remove enum wb_congested_state
  kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
  lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
  squashfs: support reading fragments in readahead call
  squashfs: implement readahead
  squashfs: always build "file direct" version of page actor
  Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
  fs/ocfs2: Fix spelling typo in comment
  ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
  proc: fix test for "vsyscall=xonly" boot option
  ...

Pull powerpc updates from Michael Ellerman:

 - Add support for syscall stack randomization

 - Add support for atomic operations to the 32 & 64-bit BPF JIT

 - Full support for KASAN on 64-bit Book3E

 - Add a watchdog driver for the new PowerVM hypervisor watchdog

 - Add a number of new selftests for the Power10 PMU support

 - Add a driver for the PowerVM Platform KeyStore

 - Increase the NMI watchdog timeout during live partition migration, to
   avoid timeouts due to increased memory access latency

 - Add support for using the 'linux,pci-domain' device tree property for
   PCI domain assignment

 - Many other small features and fixes

Thanks to Alexey Kardashevskiy, Andy Shevchenko, Arnd Bergmann, Athira
Rajeev, Bagas Sanjaya, Christophe Leroy, Erhard Furtner, Fabiano Rosas,
Greg Kroah-Hartman, Greg Kurz, Haowen Bai, Hari Bathini, Jason A.
Donenfeld, Jason Wang, Jiang Jian, Joel Stanley, Juerg Haefliger, Kajol
Jain, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Masahiro Yamada,
Maxime Bizon, Miaoqian Lin, Murilo Opsfelder Araújo, Nathan Lynch,
Naveen N.  Rao, Nayna Jain, Nicholas Piggin, Ning Qiang, Pali Rohár,
Petr Mladek, Rashmica Gupta, Sachin Sant, Scott Cheloha, Segher
Boessenkool, Stephen Rothwell, Uwe Kleine-König, Wolfram Sang, Xiu
Jianfeng, and Zhouyi Zhou.

* tag 'powerpc-6.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (191 commits)
  powerpc/64e: Fix kexec build error
  EDAC/ppc_4xx: Include required of_irq header directly
  powerpc/pci: Fix PHB numbering when using opal-phbid
  powerpc/64: Init jump labels before parse_early_param()
  selftests/powerpc: Avoid GCC 12 uninitialised variable warning
  powerpc/cell/axon_msi: Fix refcount leak in setup_msi_msg_address
  powerpc/xive: Fix refcount leak in xive_get_max_prio
  powerpc/spufs: Fix refcount leak in spufs_init_isolated_loader
  powerpc/perf: Include caps feature for power10 DD1 version
  powerpc: add support for syscall stack randomization
  powerpc: Move system_call_exception() to syscall.c
  powerpc/powernv: rename remaining rng powernv_ functions to pnv_
  powerpc/powernv/kvm: Use darn for H_RANDOM on Power9
  powerpc/powernv: Avoid crashing if rng is NULL
  selftests/powerpc: Fix matrix multiply assist test
  powerpc/signal: Update comment for clarity
  powerpc: make facility_unavailable_exception 64s
  powerpc/platforms/83xx/suspend: Remove write-only global variable
  powerpc/platforms/83xx/suspend: Prevent unloading the driver
  powerpc/platforms/83xx/suspend: Reorder to get rid of a forward declaration
  ...

Pull dma-mapping updates from Christoph Hellwig:

 - convert arm32 to the common dma-direct code (Arnd Bergmann, Robin
   Murphy, Christoph Hellwig)

 - restructure the PCIe peer to peer mapping support (Logan Gunthorpe)

 - allow the IOMMU code to communicate an optional DMA mapping length
   and use that in scsi and libata (John Garry)

 - split the global swiotlb lock (Tianyu Lan)

 - various fixes and cleanup (Chao Gao, Dan Carpenter, Dongli Zhang,
   Lukas Bulwahn, Robin Murphy)

* tag 'dma-mapping-5.20-2022-08-06' of git://git.infradead.org/users/hch/dma-mapping: (45 commits)
  swiotlb: fix passing local variable to debugfs_create_ulong()
  dma-mapping: reformat comment to suppress htmldoc warning
  PCI/P2PDMA: Remove pci_p2pdma_[un]map_sg()
  RDMA/rw: drop pci_p2pdma_[un]map_sg()
  RDMA/core: introduce ib_dma_pci_p2p_dma_supported()
  nvme-pci: convert to using dma_map_sgtable()
  nvme-pci: check DMA ops when indicating support for PCI P2PDMA
  iommu/dma: support PCI P2PDMA pages in dma-iommu map_sg
  iommu: Explicitly skip bus address marked segments in __iommu_map_sg()
  dma-mapping: add flags to dma_map_ops to indicate PCI P2PDMA support
  dma-direct: support PCI P2PDMA pages in dma-direct map_sg
  dma-mapping: allow EREMOTEIO return code for P2PDMA transfers
  PCI/P2PDMA: Introduce helpers for dma_map_sg implementations
  PCI/P2PDMA: Attempt to set map_type if it has not been set
  lib/scatterlist: add flag for indicating P2PDMA segments in an SGL
  swiotlb: clean up some coding style and minor issues
  dma-mapping: update comment after dmabounce removal
  scsi: sd: Add a comment about limiting max_sectors to shost optimal limit
  ata: libata-scsi: cap ata_device->max_sectors according to shost->max_sectors
  scsi: scsi_transport_sas: cap shost opt_sectors according to DMA optimal limit
  ...

Pull iommu updates from Joerg Roedel:

 - The most intrusive patch is small and changes the default allocation
   policy for DMA addresses.

   Before the change the allocator tried its best to find an address in
   the first 4GB. But that lead to performance problems when that space
   gets exhaused, and since most devices are capable of 64-bit DMA these
   days, we changed it to search in the full DMA-mask range from the
   beginning.

   This change has the potential to uncover bugs elsewhere, in the
   kernel or the hardware. There is a Kconfig option and a command line
   option to restore the old behavior, but none of them is enabled by
   default.

 - Add Robin Murphy as reviewer of IOMMU code and maintainer for the
   dma-iommu and iova code

 - Chaning IOVA magazine size from 1032 to 1024 bytes to save memory

 - Some core code cleanups and dead-code removal

 - Support for ACPI IORT RMR node

 - Support for multiple PCI domains in the AMD-Vi driver

 - ARM SMMU changes from Will Deacon:
      - Add even more Qualcomm device-tree compatible strings
      - Support dumping of IMP DEF Qualcomm registers on TLB sync
        timeout
      - Fix reference count leak on device tree node in Qualcomm driver

 - Intel VT-d driver updates from Lu Baolu:
      - Make intel-iommu.h private
      - Optimize the use of two locks
      - Extend the driver to support large-scale platforms
      - Cleanup some dead code

 - MediaTek IOMMU refactoring and support for TTBR up to 35bit

 - Basic support for Exynos SysMMU v7

 - VirtIO IOMMU driver gets a map/unmap_pages() implementation

 - Other smaller cleanups and fixes

* tag 'iommu-updates-v5.20-or-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (116 commits)
  iommu/amd: Fix compile warning in init code
  iommu/amd: Add support for AVIC when SNP is enabled
  iommu/amd: Simplify and Consolidate Virtual APIC (AVIC) Enablement
  ACPI/IORT: Fix build error implicit-function-declaration
  drivers: iommu: fix clang -wformat warning
  iommu/arm-smmu: qcom_iommu: Add of_node_put() when breaking out of loop
  iommu/arm-smmu-qcom: Add SM6375 SMMU compatible
  dt-bindings: arm-smmu: Add compatible for Qualcomm SM6375
  MAINTAINERS: Add Robin Murphy as IOMMU SUBSYTEM reviewer
  iommu/amd: Do not support IOMMUv2 APIs when SNP is enabled
  iommu/amd: Do not support IOMMU_DOMAIN_IDENTITY after SNP is enabled
  iommu/amd: Set translation valid bit only when IO page tables are in use
  iommu/amd: Introduce function to check and enable SNP
  iommu/amd: Globally detect SNP support
  iommu/amd: Process all IVHDs before enabling IOMMU features
  iommu/amd: Introduce global variable for storing common EFR and EFR2
  iommu/amd: Introduce Support for Extended Feature 2 Register
  iommu/amd: Change macro for IOMMU control register bit shift to decimal value
  iommu/exynos: Enable default VM instance on SysMMU v7
  iommu/exynos: Add SysMMU v7 register set
  ...