KASAN_TAG_WIDTH is 8 bits for both (HW_TAGS and SW_TAGS), but for HW_TAGS
the KASAN_TAG_WIDTH can be 4 bits bits because due to the design of the
MTE the memory words for storing metadata only need 4 bits. Change the
preprocessor define KASAN_TAG_WIDTH for check if SW_TAGS is define, so
KASAN_TAG_WIDTH should be 8 bits, but if HW_TAGS is define, so
KASAN_TAG_WIDTH should be 4 bits to save a few flags bits.
Link: https://lkml.kernel.org/r/20250428201409.5482-1-trintaeoitogc@gmail.com
Signed-off-by: Guilherme Giacomo Simoes <trintaeoitogc@gmail.com>
Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Right now these are performed in kernel/fork.c which is odd and a
violation of separation of concerns, as well as preventing us from
integrating this and related logic into userland VMA testing going
forward.
There is a fly in the ointment - nommu - mmap.c is not compiled if
CONFIG_MMU not set, and neither is vma.c.
To square the circle, let's add a new file - vma_init.c. This will be
compiled for both CONFIG_MMU and nommu builds, and will also form part of
the VMA userland testing.
This allows us to de-duplicate code, while maintaining separation of
concerns and the ability for us to userland test this logic.
Update the VMA userland tests accordingly, additionally adding a
detach_free_vma() helper function to correctly detach VMAs before freeing
them in test code, as this change was triggering the assert for this.
[akpm@linux-foundation.org: remove stray newline, per Liam]
Link: https://lkml.kernel.org/r/f97b3a85a6da0196b28070df331b99e22b263be8.1745853549.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are peculiarities within the kernel where what is very clearly mm
code is performed elsewhere arbitrarily.
This violates separation of concerns and makes it harder to refactor code
to make changes to how fundamental initialisation and operation of mm
logic is performed.
One such case is the creation of the VMA containing the initial stack upon
execve()'ing a new process. This is currently performed in
__bprm_mm_init() in fs/exec.c.
Abstract this operation to create_init_stack_vma(). This allows us to
limit use of vma allocation and free code to fork and mm only.
We previously did the same for the step at which we relocate the initial
stack VMA downwards via relocate_vma_down(), now we move the initial VMA
establishment too.
Take the opportunity to also move insert_vm_struct() to mm/vma.c as it's
no longer needed anywhere outside of mm.
Link: https://lkml.kernel.org/r/118c950ef7a8dd19ab20a23a68c3603751acd30e.1745853549.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "move all VMA allocation, freeing and duplication logic to
mm", v3.
Currently VMA allocation, freeing and duplication exist in kernel/fork.c,
which is a violation of separation of concerns, and leaves these functions
exposed to the rest of the kernel when they are in fact internal
implementation details.
Resolve this by moving this logic to mm, and making it internal to vma.c,
vma.h.
This also allows us, in future, to provide userland testing around this
functionality.
We additionally abstract dup_mmap() to mm, being careful to ensure
kernel/fork.c acceses this via the mm internal header so it is not exposed
elsewhere in the kernel.
As part of this change, also abstract initial stack allocation performed
in __bprm_mm_init() out of fs code into mm via the
create_init_stack_vma(), as this code uses vm_area_alloc() and
vm_area_free().
In order to do so sensibly, we introduce a new mm/vma_exec.c file, which
contains the code that is shared by mm and exec. This file is added to
both memory mapping and exec sections in MAINTAINERS so both sets of
maintainers can maintain oversight.
As part of this change, we also move relocate_vma_down() to mm/vma_exec.c
so all shared mm/exec functionality is kept in one place.
We add code shared between nommu and mmu-enabled configurations in order
to share VMA allocation, freeing and duplication code correctly while also
keeping these functions available in userland VMA testing.
This is achieved by adding a mm/vma_init.c file which is also compiled by
the userland tests.
This patch (of 4):
There is functionality that overlaps the exec and memory mapping
subsystems. While it properly belongs in mm, it is important that exec
maintainers maintain oversight of this functionality correctly.
We can establish both goals by adding a new mm/vma_exec.c file which
contains these 'glue' functions, and have fs/exec.c import them.
As a part of this change, to ensure that proper oversight is achieved, add
the file to both the MEMORY MAPPING and EXEC & BINFMT API, ELF sections.
scripts/get_maintainer.pl can correctly handle files in multiple entries
and this neatly handles the cross-over.
[akpm@linux-foundation.org: fix comment typo]
Link: https://lkml.kernel.org/r/80f0d0c6-0b68-47f9-ab78-0ab7f74677fc@lucifer.local
Link: https://lkml.kernel.org/r/cover.1745853549.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/91f2cee8f17d65214a9d83abb7011aa15f1ea690.1745853549.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series " JFS: Implement migrate_folio for jfs_metapage_aops" v5.
This patchset addresses a warning that occurs during memory compaction due
to JFS's missing migrate_folio operation. The warning was introduced by
commit 7ee3647243 ("migrate: Remove call to ->writepage") which added
explicit warnings when filesystem don't implement migrate_folio.
The syzbot reported following [1]:
jfs_metapage_aops does not implement migrate_folio
WARNING: CPU: 1 PID: 5861 at mm/migrate.c:955 fallback_migrate_folio mm/migrate.c:953 [inline]
WARNING: CPU: 1 PID: 5861 at mm/migrate.c:955 move_to_new_folio+0x70e/0x840 mm/migrate.c:1007
Modules linked in:
CPU: 1 UID: 0 PID: 5861 Comm: syz-executor280 Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:fallback_migrate_folio mm/migrate.c:953 [inline]
RIP: 0010:move_to_new_folio+0x70e/0x840 mm/migrate.c:1007
To fix this issue, this series implement metapage_migrate_folio() for JFS
which handles both single and multiple metapages per page configurations.
While most filesystems leverage existing migration implementations like
filemap_migrate_folio(), buffer_migrate_folio_norefs() or
buffer_migrate_folio() (which internally used folio_expected_refs()),
JFS's metapage architecture requires special handling of its private data
during migration. To support this, this series introduce the
folio_expected_ref_count(), which calculates external references to a
folio from page/swap cache, private data, and page table mappings.
This standardized implementation replaces the previous ad-hoc
folio_expected_refs() function and enables JFS to accurately determine
whether a folio has unexpected references before attempting migration.
Implement folio_expected_ref_count() to calculate expected folio reference
counts from:
- Page/swap cache (1 per page)
- Private data (1)
- Page table mappings (1 per map)
While originally needed for page migration operations, this improved
implementation standardizes reference counting by consolidating all
refcount contributors into a single, reusable function that can benefit
any subsystem needing to detect unexpected references to folios.
The folio_expected_ref_count() returns the sum of these external
references without including any reference the caller itself might hold.
Callers comparing against the actual folio_ref_count() must account for
their own references separately.
Link: https://syzkaller.appspot.com/bug?extid=8bb6fd945af4e0ad9299 [1]
Link: https://lkml.kernel.org/r/20250430100150.279751-1-shivankg@amd.com
Link: https://lkml.kernel.org/r/20250430100150.279751-2-shivankg@amd.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Shivank Garg <shivankg@amd.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Co-developed-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add an unit test to verify the recent mmap_changing ABI breakage.
Note that I used some tricks here and there to make the test simple, e.g.
I abused UFFDIO_MOVE on top of shmem with the fact that I know what I want
to test will be even earlier than the vma type check. Rich comments were
added to explain trivial details.
Before that fix, -EAGAIN would have been written to the copy field most of
the time but not always; the test should be able to reliably trigger the
outlier case. After the fix, it's written always, the test verifies that
making sure corresponding field (e.g. copy.copy for UFFDIO_COPY) is
updated.
[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/20250424215729.194656-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm: Introduce for_each_valid_pfn()", v4.
There are cases where a naïve loop over a PFN range, calling pfn_valid()
on each one, is horribly inefficient. Ruihan Li reported the case where
memmap_init() iterates all the way from zero to a potentially large value
of ARCH_PFN_OFFSET, and we at Amazon found the reserve_bootmem_region()
one as it affects hypervisor live update. Others are more cosmetic.
By introducing a for_each_valid_pfn() helper it can optimise away a lot of
pointless calls to pfn_valid(), skipping immediately to the next valid PFN
and also skipping *all* checks within a valid (sub)region according to the
granularity of the memory model in use.
This patch (of 7)
Especially since commit 9092d4f7a1 ("memblock: update initialization of
reserved pages"), the reserve_bootmem_region() function can spend a
significant amount of time iterating over every 4KiB PFN in a range,
calling pfn_valid() on each one, and ultimately doing absolutely nothing.
On a platform used for virtualization, with large NOMAP regions that
eventually get used for guest RAM, this leads to a significant increase in
steal time experienced during kexec for a live update.
Introduce for_each_valid_pfn() and use it from reserve_bootmem_region().
This implementation is precisely the same naïve loop that the functio
used to have, but subsequent commits will provide optimised versions for
FLATMEM and SPARSEMEM, and this version will remain for those
architectures which provide their own pfn_valid() implementation,
until/unless they also provide a matching for_each_valid_pfn().
Link: https://lkml.kernel.org/r/20250423133821.789413-1-dwmw2@infradead.org
Link: https://lkml.kernel.org/r/20250423133821.789413-2-dwmw2@infradead.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Ruihan Li <lrh2000@pku.edu.cn>
Cc: Will Deacon <will@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
With KHO (Kexec HandOver), we need a way to ensure that the new kernel
does not allocate memory on top of any memory regions that the previous
kernel was handing over. But to know where those are, we need to include
them in the memblock.reserved array which may not be big enough to hold
all ranges that need to be persisted across kexec. To resize the array,
we need to allocate memory. That brings us into a catch 22 situation.
The solution to that is limit memblock allocations to the scratch regions:
safe regions to operate in the case when there is memory that should
remain intact across kexec.
KHO provides several "scratch regions" as part of its metadata. These
scratch regions are contiguous memory blocks that known not to contain any
memory that should be persisted across kexec. These regions should be
large enough to accommodate all memblock allocations done by the kexeced
kernel.
We introduce a new memblock_set_scratch_only() function that allows KHO to
indicate that any memblock allocation must happen from the scratch
regions.
Later, we may want to perform another KHO kexec. For that, we reuse the
same scratch regions. To ensure that no eventually handed over data gets
allocated inside a scratch region, we flip the semantics of the scratch
region with memblock_clear_scratch_only(): After that call, no allocations
may happen from scratch memblock regions. We will lift that restriction
in the next patch.
Link: https://lkml.kernel.org/r/20250509074635.3187114-3-changyuanl@google.com
Signed-off-by: Alexander Graf <graf@amazon.com>
Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Changyuan Lyu <changyuanl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anthony Yznaga <anthony.yznaga@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ashish Kalra <ashish.kalra@amd.com>
Cc: Ben Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Gowans <jgowans@amazon.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pratyush Yadav <ptyadav@amazon.de>
Cc: Rob Herring <robh@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Thomas Lendacky <thomas.lendacky@amd.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "kexec: introduce Kexec HandOver (KHO)", v8.
Kexec today considers itself purely a boot loader: When we enter the new
kernel, any state the previous kernel left behind is irrelevant and the
new kernel reinitializes the system.
However, there are use cases where this mode of operation is not what we
actually want. In virtualization hosts for example, we want to use kexec
to update the host kernel while virtual machine memory stays untouched.
When we add device assignment to the mix, we also need to ensure that
IOMMU and VFIO states are untouched. If we add PCIe peer to peer DMA, we
need to do the same for the PCI subsystem. If we want to kexec while an
SEV-SNP enabled virtual machine is running, we need to preserve the VM
context pages and physical memory. See "pkernfs: Persisting guest memory
and kernel/device state safely across kexec" Linux Plumbers Conference
2023 presentation for details:
https://lpc.events/event/17/contributions/1485/
To start us on the journey to support all the use cases above, this patch
implements basic infrastructure to allow hand over of kernel state across
kexec (Kexec HandOver, aka KHO). As a really simple example target, we
use memblock's reserve_mem.
With this patchset applied, memory that was reserved using "reserve_mem"
command line options remains intact after kexec and it is guaranteed to
reside at the same physical address.
== Alternatives ==
There are alternative approaches to (parts of) the problems above:
* Memory Pools [1] - preallocated persistent memory region + allocator
* PRMEM [2] - resizable persistent memory regions with fixed metadata
pointer on the kernel command line + allocator
* Pkernfs [3] - preallocated file system for in-kernel data with fixed
address location on the kernel command line
* PKRAM [4] - handover of user space pages using a fixed metadata page
specified via command line
All of the approaches above fundamentally have the same problem: They
require the administrator to explicitly carve out a physical memory
location because they have no mechanism outside of the kernel command line
to pass data (including memory reservations) between kexec'ing kernels.
KHO provides that base foundation. We will determine later whether we
still need any of the approaches above for fast bulk memory handover of
for example IOMMU page tables. But IMHO they would all be users of KHO,
with KHO providing the foundational primitive to pass metadata and bulk
memory reservations as well as provide easy versioning for data.
== Overview ==
We introduce a metadata file that the kernels pass between each other.
How they pass it is architecture specific. The file's format is a
Flattened Device Tree (fdt) which has a generator and parser already
included in Linux. KHO is enabled in the kernel command line by `kho=on`.
When the root user enables KHO through
/sys/kernel/debug/kho/out/finalize, the kernel invokes callbacks to every
KHO users to register preserved memory regions, which contain drivers'
states.
When the actual kexec happens, the fdt is part of the image set that we
boot into. In addition, we keep "scratch regions" available for kexec:
physically contiguous memory regions that are guaranteed to not have any
memory that KHO would preserve. The new kernel bootstraps itself using
the scratch regions and sets all handed over memory as in use. When
drivers initialize that support KHO, they introspect the fdt, restore
preserved memory regions, and retrieve their states stored in the
preserved memory.
== Limitations ==
Currently KHO is only implemented for file based kexec. The kernel
interfaces in the patch set are already in place to support user space
kexec as well, but it is still not implemented it yet inside kexec tools.
== How to Use ==
To use the code, please boot the kernel with the "kho=on" command line
parameter. KHO will automatically create scratch regions. If you want to
set the scratch size explicitly you can use "kho_scratch=" command line
parameter. For instance, "kho_scratch=16M,512M,256M" will reserve a 16
MiB low memory scratch area, a 512 MiB global scratch region, and 256 MiB
per NUMA node scratch regions on boot.
Make sure to have a reserved memory range requested with reserv_mem
command line option, for example, "reserve_mem=64m:4k:n1".
Then before you invoke file based "kexec -l", finalize KHO FDT:
# echo 1 > /sys/kernel/debug/kho/out/finalize
You can preview the generated FDT using `dtc`,
# dtc /sys/kernel/debug/kho/out/fdt
# dtc /sys/kernel/debug/kho/out/sub_fdts/memblock
`dtc` is available on ubuntu by `sudo apt-get install device-tree-compiler`.
Now kexec into the new kernel,
# kexec -l Image --initrd=initrd -s
# kexec -e
(The order of KHO finalization and "kexec -l" does not matter.)
The new kernel will boot up and contain the previous kernel's reserve_mem
contents at the same physical address as the first kernel.
You can also review the FDT passed from the old kernel,
# dtc /sys/kernel/debug/kho/in/fdt
# dtc /sys/kernel/debug/kho/in/sub_fdts/memblock
This patch (of 17):
To denote areas that were reserved for kernel use either directly with
memblock_reserve_kern() or via memblock allocations.
Link: https://lore.kernel.org/lkml/20250424083258.2228122-1-changyuanl@google.com/
Link: https://lore.kernel.org/lkml/aAeaJ2iqkrv_ffhT@kernel.org/
Link: https://lore.kernel.org/lkml/35c58191-f774-40cf-8d66-d1e2aaf11a62@intel.com/
Link: https://lore.kernel.org/lkml/20250424093302.3894961-1-arnd@kernel.org/
Link: https://lkml.kernel.org/r/20250509074635.3187114-1-changyuanl@google.com
Link: https://lkml.kernel.org/r/20250509074635.3187114-2-changyuanl@google.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Co-developed-by: Changyuan Lyu <changyuanl@google.com>
Signed-off-by: Changyuan Lyu <changyuanl@google.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anthony Yznaga <anthony.yznaga@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ashish Kalra <ashish.kalra@amd.com>
Cc: Ben Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Gowans <jgowans@amazon.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pratyush Yadav <ptyadav@amazon.de>
Cc: Rob Herring <robh@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Thomas Lendacky <thomas.lendacky@amd.com>
Cc: Will Deacon <will@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change the type of 'dwRegionSize' in wp_init() and wp_free() from int to
long to match callers that pass long or unsigned long long values.
wp_addr_range function is left unchanged because it passes 'dwRegionSize'
parameter directly to pagemap_ioctl, which expects an int.
This patch does not fix any actual known issues. It aligns parameter
types with their actual usage and avoids any potential future issues.
Link: https://lkml.kernel.org/r/20250427102639.39978-1-siddarthsgml@gmail.com
Signed-off-by: Siddarth G <siddarthsgml@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
