This reverts commit bde9cfa3afe4324ec251e4af80ebf9b7afaf7afe.

Changing the first memory page type from E820_TYPE_RESERVED to
E820_TYPE_RAM makes it a part of "System RAM" resource rather than a
reserved resource and this in turn causes devmem_is_allowed() to treat
is as area that can be accessed but it is filled with zeroes instead of
the actual data as previously.

The change in /dev/mem output causes lilo to fail as was reported at
slakware users forum, and probably other legacy applications will
experience similar problems.

Link: https://www.linuxquestions.org/questions/slackware-14/slackware-current-lilo-vesa-warnings-after-recent-updates-4175689617/#post6214439
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "mm: fix initialization of struct page for holes in  memory layout", v3.

Commit 73a6e474cb37 ("mm: memmap_init: iterate over memblock regions
rather that check each PFN") exposed several issues with the memory map
initialization and these patches fix those issues.

Initially there were crashes during compaction that Qian Cai reported
back in April [1].  It seemed back then that the problem was fixed, but
a few weeks ago Andrea Arcangeli hit the same bug [2] and there was an
additional discussion at [3].

[1] https://lore.kernel.org/lkml/8C537EB7-85EE-4DCF-943E-3CC0ED0DF56D@lca.pw
[2] https://lore.kernel.org/lkml/20201121194506.13464-1-aarcange@redhat.com
[3] https://lore.kernel.org/mm-commits/20201206005401.qKuAVgOXr%akpm@linux-foundation.org

This patch (of 2):

The first 4Kb of memory is a BIOS owned area and to avoid its allocation
for the kernel it was not listed in e820 tables as memory.  As the result,
pfn 0 was never recognised by the generic memory management and it is not
a part of neither node 0 nor ZONE_DMA.

If set_pfnblock_flags_mask() would be ever called for the pageblock
corresponding to the first 2Mbytes of memory, having pfn 0 outside of
ZONE_DMA would trigger

	VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page);

Along with reserving the first 4Kb in e820 tables, several first pages are
reserved with memblock in several places during setup_arch().  These
reservations are enough to ensure the kernel does not touch the BIOS area
and it is not necessary to remove E820_TYPE_RAM for pfn 0.

Remove the update of e820 table that changes the type of pfn 0 and move
the comment describing why it was done to trim_low_memory_range() that
reserves the beginning of the memory.

Link: https://lkml.kernel.org/r/20210111194017.22696-2-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull swiotlb update from Konrad Rzeszutek Wilk:
 "A generic (but for right now engaged only with AMD SEV) mechanism to
  adjust a larger size SWIOTLB based on the total memory of the SEV
  guests which right now require the bounce buffer for interacting with
  the outside world.

  Normal knobs (swiotlb=XYZ) still work"

* 'stable/for-linus-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  x86,swiotlb: Adjust SWIOTLB bounce buffer size for SEV guests

For SEV, all DMA to and from guest has to use shared (un-encrypted) pages.
SEV uses SWIOTLB to make this happen without requiring changes to device
drivers.  However, depending on the workload being run, the default 64MB
of it might not be enough and it may run out of buffers to use for DMA,
resulting in I/O errors and/or performance degradation for high
I/O workloads.

Adjust the default size of SWIOTLB for SEV guests using a
percentage of the total memory available to guest for the SWIOTLB buffers.

Adds a new sev_setup_arch() function which is invoked from setup_arch()
and it calls into a new swiotlb generic code function swiotlb_adjust_size()
to do the SWIOTLB buffer adjustment.

v5 fixed build errors and warnings as
Reported-by: kbuild test robot <lkp@intel.com>

Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Co-developed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Commit

  bb8187d35f82 ("MCA: delete all remaining traces of microchannel bus support.")

removed the remaining traces of Micro Channel Architecture support but
one trace remained - three variables in setup.c which have been unused
since 2012 at least.

Drop them finally.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201021165614.23023-1-bp@alien8.de

Pull dma-mapping updates from Christoph Hellwig:

 - rework the non-coherent DMA allocator

 - move private definitions out of <linux/dma-mapping.h>

 - lower CMA_ALIGNMENT (Paul Cercueil)

 - remove the omap1 dma address translation in favor of the common code

 - make dma-direct aware of multiple dma offset ranges (Jim Quinlan)

 - support per-node DMA CMA areas (Barry Song)

 - increase the default seg boundary limit (Nicolin Chen)

 - misc fixes (Robin Murphy, Thomas Tai, Xu Wang)

 - various cleanups

* tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits)
  ARM/ixp4xx: add a missing include of dma-map-ops.h
  dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
  dma-direct: factor out a dma_direct_alloc_from_pool helper
  dma-direct check for highmem pages in dma_direct_alloc_pages
  dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
  dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
  dma-mapping: move dma-debug.h to kernel/dma/
  dma-mapping: remove <asm/dma-contiguous.h>
  dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
  dma-contiguous: remove dma_contiguous_set_default
  dma-contiguous: remove dev_set_cma_area
  dma-contiguous: remove dma_declare_contiguous
  dma-mapping: split <linux/dma-mapping.h>
  cma: decrease CMA_ALIGNMENT lower limit to 2
  firewire-ohci: use dma_alloc_pages
  dma-iommu: implement ->alloc_noncoherent
  dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
  dma-mapping: add a new dma_alloc_pages API
  dma-mapping: remove dma_cache_sync
  53c700: convert to dma_alloc_noncoherent
  ...

Pull ACPI updates from Rafael Wysocki:
 "These add support for generic initiator-only proximity domains to the
  ACPI NUMA code and the architectures using it, clean up some
  non-ACPICA code referring to debug facilities from ACPICA, reduce the
  overhead related to accessing GPE registers, add a new DPTF (Dynamic
  Power and Thermal Framework) participant driver, update the ACPICA
  code in the kernel to upstream revision 20200925, add a new ACPI
  backlight whitelist entry, fix a few assorted issues and clean up some
  code.

  Specifics:

   - Add support for generic initiator-only proximity domains to the
     ACPI NUMA code and the architectures using it (Jonathan Cameron)

   - Clean up some non-ACPICA code referring to debug facilities from
     ACPICA that are not actually used in there (Hanjun Guo)

   - Add new DPTF driver for the PCH FIVR participant (Srinivas
     Pandruvada)

   - Reduce overhead related to accessing GPE registers in ACPICA and
     the OS interface layer and make it possible to access GPE registers
     using logical addresses if they are memory-mapped (Rafael Wysocki)

   - Update the ACPICA code in the kernel to upstream revision 20200925
     including changes as follows:
      + Add predefined names from the SMBus sepcification (Bob Moore)
      + Update acpi_help UUID list (Bob Moore)
      + Return exceptions for string-to-integer conversions in iASL (Bob
        Moore)
      + Add a new "ALL <NameSeg>" debugger command (Bob Moore)
      + Add support for 64 bit risc-v compilation (Colin Ian King)
      + Do assorted cleanups (Bob Moore, Colin Ian King, Randy Dunlap)

   - Add new ACPI backlight whitelist entry for HP 635 Notebook (Alex
     Hung)

   - Move TPS68470 OpRegion driver to drivers/acpi/pmic/ and split out
     Kconfig and Makefile specific for ACPI PMIC (Andy Shevchenko)

   - Clean up the ACPI SoC driver for AMD SoCs (Hanjun Guo)

   - Add missing config_item_put() to fix refcount leak (Hanjun Guo)

   - Drop lefrover field from struct acpi_memory_device (Hanjun Guo)

   - Make the ACPI extlog driver check for RDMSR failures (Ben
     Hutchings)

   - Fix handling of lid state changes in the ACPI button driver when
     input device is closed (Dmitry Torokhov)

   - Fix several assorted build issues (Barnabás Pőcze, John Garry,
     Nathan Chancellor, Tian Tao)

   - Drop unused inline functions and reduce code duplication by using
     kobj_to_dev() in the NFIT parsing code (YueHaibing, Wang Qing)

   - Serialize tools/power/acpi Makefile (Thomas Renninger)"

* tag 'acpi-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (64 commits)
  ACPICA: Update version to 20200925 Version 20200925
  ACPICA: Remove unnecessary semicolon
  ACPICA: Debugger: Add a new command: "ALL <NameSeg>"
  ACPICA: iASL: Return exceptions for string-to-integer conversions
  ACPICA: acpi_help: Update UUID list
  ACPICA: Add predefined names found in the SMBus sepcification
  ACPICA: Tree-wide: fix various typos and spelling mistakes
  ACPICA: Drop the repeated word "an" in a comment
  ACPICA: Add support for 64 bit risc-v compilation
  ACPI: button: fix handling lid state changes when input device closed
  tools/power/acpi: Serialize Makefile
  ACPI: scan: Replace ACPI_DEBUG_PRINT() with pr_debug()
  ACPI: memhotplug: Remove 'state' from struct acpi_memory_device
  ACPI / extlog: Check for RDMSR failure
  ACPI: Make acpi_evaluate_dsm() prototype consistent
  docs: mm: numaperf.rst Add brief description for access class 1.
  node: Add access1 class to represent CPU to memory characteristics
  ACPI: HMAT: Fix handling of changes from ACPI 6.2 to ACPI 6.3
  ACPI: Let ACPI know we support Generic Initiator Affinity Structures
  x86: Support Generic Initiator only proximity domains
  ...

* Replace magic numbers with defines
* Replace memblock_find_in_range() + memblock_reserve() with
  memblock_phys_alloc_range()
* Stop checking for low memory size in reserve_crashkernel_low(). The
  allocation from limited range will anyway fail if there is no enough
  memory, so there is no need for extra traversal of memblock.memory

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Emil Renner Berthing <kernel@esmil.dk>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20200818151634.14343-15-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently, initrd image is reserved very early during setup and then it
might be relocated and re-reserved after the initial physical memory
mapping is created.  The "late" reservation of memblock verifies that
mapped memory size exceeds the size of initrd, then checks whether the
relocation required and, if yes, relocates inirtd to a new memory
allocated from memblock and frees the old location.

The check for memory size is excessive as memblock allocation will anyway
fail if there is not enough memory.  Besides, there is no point to
allocate memory from memblock using memblock_find_in_range() +
memblock_reserve() when there exists memblock_phys_alloc_range() with
required functionality.

Remove the redundant check and simplify memblock allocation.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Emil Renner Berthing <kernel@esmil.dk>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20200818151634.14343-14-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull static call support from Ingo Molnar:
 "This introduces static_call(), which is the idea of static_branch()
  applied to indirect function calls. Remove a data load (indirection)
  by modifying the text.

  They give the flexibility of function pointers, but with better
  performance. (This is especially important for cases where retpolines
  would otherwise be used, as retpolines can be pretty slow.)

  API overview:

      DECLARE_STATIC_CALL(name, func);
      DEFINE_STATIC_CALL(name, func);
      DEFINE_STATIC_CALL_NULL(name, typename);

      static_call(name)(args...);
      static_call_cond(name)(args...);
      static_call_update(name, func);

  x86 is supported via text patching, otherwise basic indirect calls are
  used, with function pointers.

  There's a second variant using inline code patching, inspired by
  jump-labels, implemented on x86 as well.

  The new APIs are utilized in the x86 perf code, a heavy user of
  function pointers, where static calls speed up the PMU handler by
  4.2% (!).

  The generic implementation is not really excercised on other
  architectures, outside of the trivial test_static_call_init()
  self-test"

* tag 'core-static_call-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  static_call: Fix return type of static_call_init
  tracepoint: Fix out of sync data passing by static caller
  tracepoint: Fix overly long tracepoint names
  x86/perf, static_call: Optimize x86_pmu methods
  tracepoint: Optimize using static_call()
  static_call: Allow early init
  static_call: Add some validation
  static_call: Handle tail-calls
  static_call: Add static_call_cond()
  x86/alternatives: Teach text_poke_bp() to emulate RET
  static_call: Add simple self-test for static calls
  x86/static_call: Add inline static call implementation for x86-64
  x86/static_call: Add out-of-line static call implementation
  static_call: Avoid kprobes on inline static_call()s
  static_call: Add inline static call infrastructure
  static_call: Add basic static call infrastructure
  compiler.h: Make __ADDRESSABLE() symbol truly unique
  jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved()
  module: Properly propagate MODULE_STATE_COMING failure
  module: Fix up module_notifier return values
  ...