<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel.git/arch/powerpc/mm, branch linux-6.17.y</title>
<subtitle>Hosts the 0x221E linux distro kernel.
</subtitle>
<id>https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.17.y</id>
<link rel='self' href='https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-6.17.y'/>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/'/>
<updated>2025-12-18T12:59:46Z</updated>
<entry>
<title>powerpc/64s/ptdump: Fix kernel_hash_pagetable dump for ISA v3.00 HPTE format</title>
<updated>2025-12-18T12:59:46Z</updated>
<author>
<name>Ritesh Harjani (IBM)</name>
</author>
<published>2025-10-30T14:57:28Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=b2cc9f08cb412900bff4b537f7c2e0e3fc8d8df0'/>
<id>urn:sha1:b2cc9f08cb412900bff4b537f7c2e0e3fc8d8df0</id>
<content type='text'>
[ Upstream commit eae40a6da63faa9fb63ff61f8fa2b3b57da78a84 ]

HPTE format was changed since Power9 (ISA 3.0) onwards. While dumping
kernel hash page tables, nothing gets printed on powernv P9+. This patch
utilizes the helpers added in the patch tagged as fixes, to convert new
format to old format and dump the hptes. This fix is only needed for
native_find() (powernv), since pseries continues to work fine with the
old format.

Fixes: 6b243fcfb5f1e ("powerpc/64: Simplify adaptation to new ISA v3.00 HPTE format")
Signed-off-by: Ritesh Harjani (IBM) &lt;ritesh.list@gmail.com&gt;
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/4c2bb9e5b3cfbc0dd80b61b67cdd3ccfc632684c.1761834163.git.ritesh.list@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>powerpc/64s/hash: Restrict stress_hpt_struct memblock region to within RMA limit</title>
<updated>2025-12-18T12:59:45Z</updated>
<author>
<name>Ritesh Harjani (IBM)</name>
</author>
<published>2025-10-30T14:57:27Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=a29c7021ac8908996229de5d117482d9d66e46ad'/>
<id>urn:sha1:a29c7021ac8908996229de5d117482d9d66e46ad</id>
<content type='text'>
[ Upstream commit 17b45ccf09882e0c808ad2cf62acdc90ad968746 ]

When HV=0 &amp; IR/DR=0, the Hash MMU is said to be in Virtual Real
Addressing Mode during early boot. During this, we should ensure that
memory region allocations for stress_hpt_struct should happen from
within RMA region as otherwise the boot might get stuck while doing
memset of this region.

History behind why do we have RMA region limitation is better explained
in these 2 patches [1] &amp; [2]. This patch ensures that memset to
stress_hpt_struct during early boot does not cross ppc64_rma_size
boundary.

[1]: https://lore.kernel.org/all/20190710052018.14628-1-sjitindarsingh@gmail.com/
[2]: https://lore.kernel.org/all/87wp54usvj.fsf@linux.vnet.ibm.com/

Fixes: 6b34a099faa12 ("powerpc/64s/hash: add stress_hpt kernel boot option to increase hash faults")
Signed-off-by: Ritesh Harjani (IBM) &lt;ritesh.list@gmail.com&gt;
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/ada1173933ea7617a994d6ee3e54ced8797339fc.1761834163.git.ritesh.list@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>powerpc/32: Remove PAGE_KERNEL_TEXT to fix startup failure</title>
<updated>2025-10-29T13:10:17Z</updated>
<author>
<name>Christophe Leroy</name>
</author>
<published>2025-09-09T10:03:49Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=3739560a7d1ba64ae006ba250f7e9e4c49e89210'/>
<id>urn:sha1:3739560a7d1ba64ae006ba250f7e9e4c49e89210</id>
<content type='text'>
[ Upstream commit 9316512b717f6f25c4649b3fdb0a905b6a318e9f ]

PAGE_KERNEL_TEXT is an old macro that is used to tell kernel whether
kernel text has to be mapped read-only or read-write based on build
time options.

But nowadays, with functionnalities like jump_labels, static links,
etc ... more only less all kernels need to be read-write at some
point, and some combinations of configs failed to work due to
innacurate setting of PAGE_KERNEL_TEXT. On the other hand, today
we have CONFIG_STRICT_KERNEL_RWX which implements a more controlled
access to kernel modifications.

Instead of trying to keep PAGE_KERNEL_TEXT accurate with all
possible options that may imply kernel text modification, always
set kernel text read-write at startup and rely on
CONFIG_STRICT_KERNEL_RWX to provide accurate protection.

Do this by passing PAGE_KERNEL_X to map_kernel_page() in
__maping_ram_chunk() instead of passing PAGE_KERNEL_TEXT. Once
this is done, the only remaining user of PAGE_KERNEL_TEXT is
mmu_mark_initmem_nx() which uses it in a call to setibat().
As setibat() ignores the RW/RO, we can seamlessly replace
PAGE_KERNEL_TEXT by PAGE_KERNEL_X here as well and get rid of
PAGE_KERNEL_TEXT completely.

Reported-by: Erhard Furtner &lt;erhard_f@mailbox.org&gt;
Closes: https://lore.kernel.org/all/342b4120-911c-4723-82ec-d8c9b03a8aef@mailbox.org/
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Tested-by: Andrew Donnellan &lt;ajd@linux.ibm.com&gt;
Signed-off-by: Madhavan Srinivasan &lt;maddy@linux.ibm.com&gt;
Link: https://patch.msgid.link/8e2d793abf87ae3efb8f6dce10f974ac0eda61b8.1757412205.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2025-08-03T23:23:09Z</updated>
<author>
<name>Linus Torvalds</name>
</author>
<published>2025-08-03T23:23:09Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=e991acf1bce7a428794514cbbe216973c9c0a3c8'/>
<id>urn:sha1:e991acf1bce7a428794514cbbe216973c9c0a3c8</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:
 "Significant patch series in this pull request:

   - "squashfs: Remove page-&gt;mapping references" (Matthew Wilcox) gets
     us closer to being able to remove page-&gt;mapping

   - "relayfs: misc changes" (Jason Xing) does some maintenance and
     minor feature addition work in relayfs

   - "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches
     us from static preallocation of the kdump crashkernel's working
     memory over to dynamic allocation. So the difficulty of a-priori
     estimation of the second kernel's needs is removed and the first
     kernel obtains extra memory

   - "generalize panic_print's dump function to be used by other
     kernel parts" (Feng Tang) implements some consolidation and
     rationalization of the various ways in which a failing kernel
     splats information at the operator

* tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits)
  tools/getdelays: add backward compatibility for taskstats version
  kho: add test for kexec handover
  delaytop: enhance error logging and add PSI feature description
  samples: Kconfig: fix spelling mistake "instancess" -&gt; "instances"
  fat: fix too many log in fat_chain_add()
  scripts/spelling.txt: add notifer||notifier to spelling.txt
  xen/xenbus: fix typo "notifer"
  net: mvneta: fix typo "notifer"
  drm/xe: fix typo "notifer"
  cxl: mce: fix typo "notifer"
  KVM: x86: fix typo "notifer"
  MAINTAINERS: add maintainers for delaytop
  ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below()
  ucount: fix atomic_long_inc_below() argument type
  kexec: enable CMA based contiguous allocation
  stackdepot: make max number of pools boot-time configurable
  lib/xxhash: remove unused functions
  init/Kconfig: restore CONFIG_BROKEN help text
  lib/raid6: update recov_rvv.c zero page usage
  docs: update docs after introducing delaytop
  ...
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2025-07-31T21:57:54Z</updated>
<author>
<name>Linus Torvalds</name>
</author>
<published>2025-07-31T21:57:54Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=beace86e61e465dba204a268ab3f3377153a4973'/>
<id>urn:sha1:beace86e61e465dba204a268ab3f3377153a4973</id>
<content type='text'>
Pull MM updates from Andrew Morton:
 "As usual, many cleanups. The below blurbiage describes 42 patchsets.
  21 of those are partially or fully cleanup work. "cleans up",
  "cleanup", "maintainability", "rationalizes", etc.

  I never knew the MM code was so dirty.

  "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
     addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
     mapped VMAs were not eligible for merging with existing adjacent
     VMAs.

  "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
     adds a new kernel module which simplifies the setup and usage of
     DAMON in production environments.

  "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
     is a cleanup to the writeback code which removes a couple of
     pointers from struct writeback_control.

  "drivers/base/node.c: optimization and cleanups" (Donet Tom)
     contains largely uncorrelated cleanups to the NUMA node setup and
     management code.

  "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
     does some maintenance work on the userfaultfd code.

  "Readahead tweaks for larger folios" (Ryan Roberts)
     implements some tuneups for pagecache readahead when it is reading
     into order&gt;0 folios.

  "selftests/mm: Tweaks to the cow test" (Mark Brown)
     provides some cleanups and consistency improvements to the
     selftests code.

  "Optimize mremap() for large folios" (Dev Jain)
     does that. A 37% reduction in execution time was measured in a
     memset+mremap+munmap microbenchmark.

  "Remove zero_user()" (Matthew Wilcox)
     expunges zero_user() in favor of the more modern memzero_page().

  "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
     addresses some warts which David noticed in the huge page code.
     These were not known to be causing any issues at this time.

  "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
     provides some cleanup and consolidation work in DAMON.

  "use vm_flags_t consistently" (Lorenzo Stoakes)
     uses vm_flags_t in places where we were inappropriately using other
     types.

  "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
     increases the reliability of large page allocation in the memfd
     code.

  "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
     removes several now-unneeded PFN_* flags.

  "mm/damon: decouple sysfs from core" (SeongJae Park)
     implememnts some cleanup and maintainability work in the DAMON
     sysfs layer.

  "madvise cleanup" (Lorenzo Stoakes)
     does quite a lot of cleanup/maintenance work in the madvise() code.

  "madvise anon_name cleanups" (Vlastimil Babka)
     provides additional cleanups on top or Lorenzo's effort.

  "Implement numa node notifier" (Oscar Salvador)
     creates a standalone notifier for NUMA node memory state changes.
     Previously these were lumped under the more general memory
     on/offline notifier.

  "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
     cleans up the pageblock isolation code and fixes a potential issue
     which doesn't seem to cause any problems in practice.

  "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
     adds additional drgn- and python-based DAMON selftests which are
     more comprehensive than the existing selftest suite.

  "Misc rework on hugetlb faulting path" (Oscar Salvador)
     fixes a rather obscure deadlock in the hugetlb fault code and
     follows that fix with a series of cleanups.

  "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
     rationalizes and cleans up the highmem-specific code in the CMA
     allocator.

  "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
     provides cleanups and future-preparedness to the migration code.

  "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
     adds some tracepoints to some DAMON auto-tuning code.

  "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
     does that.

  "mm/damon: misc cleanups" (SeongJae Park)
     also does what it claims.

  "mm: folio_pte_batch() improvements" (David Hildenbrand)
     cleans up the large folio PTE batching code.

  "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
     facilitates dynamic alteration of DAMON's inter-node allocation
     policy.

  "Remove unmap_and_put_page()" (Vishal Moola)
     provides a couple of page-&gt;folio conversions.

  "mm: per-node proactive reclaim" (Davidlohr Bueso)
     implements a per-node control of proactive reclaim - beyond the
     current memcg-based implementation.

  "mm/damon: remove damon_callback" (SeongJae Park)
     replaces the damon_callback interface with a more general and
     powerful damon_call()+damos_walk() interface.

  "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
     implements a number of mremap cleanups (of course) in preparation
     for adding new mremap() functionality: newly permit the remapping
     of multiple VMAs when the user is specifying MREMAP_FIXED. It still
     excludes some specialized situations where this cannot be performed
     reliably.

  "drop hugetlb_free_pgd_range()" (Anthony Yznaga)
     switches some sparc hugetlb code over to the generic version and
     removes the thus-unneeded hugetlb_free_pgd_range().

  "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
     augments the present userspace-requested update of DAMON sysfs
     monitoring files. Automatic update is now provided, along with a
     tunable to control the update interval.

  "Some randome fixes and cleanups to swapfile" (Kemeng Shi)
     does what is claims.

  "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
     provides (and uses) a means by which debug-style functions can grab
     a copy of a pageframe and inspect it locklessly without tripping
     over the races inherent in operating on the live pageframe
     directly.

  "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
     addresses the large contention issues which can be triggered by
     reads from that procfs file. Latencies are reduced by more than
     half in some situations. The series also introduces several new
     selftests for the /proc/pid/maps interface.

  "__folio_split() clean up" (Zi Yan)
     cleans up __folio_split()!

  "Optimize mprotect() for large folios" (Dev Jain)
     provides some quite large (&gt;3x) speedups to mprotect() when dealing
     with large folios.

  "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
     does some cleanup work in the selftests code.

  "tools/testing: expand mremap testing" (Lorenzo Stoakes)
     extends the mremap() selftest in several ways, including adding
     more checking of Lorenzo's recently added "permit mremap() move of
     multiple VMAs" feature.

  "selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
     extends the DAMON sysfs interface selftest so that it tests all
     possible user-requested parameters. Rather than the present minimal
     subset"

* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
  MAINTAINERS: add missing headers to mempory policy &amp; migration section
  MAINTAINERS: add missing file to cgroup section
  MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
  MAINTAINERS: add missing zsmalloc file
  MAINTAINERS: add missing files to page alloc section
  MAINTAINERS: add missing shrinker files
  MAINTAINERS: move memremap.[ch] to hotplug section
  MAINTAINERS: add missing mm_slot.h file THP section
  MAINTAINERS: add missing interval_tree.c to memory mapping section
  MAINTAINERS: add missing percpu-internal.h file to per-cpu section
  mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
  selftests/damon: introduce _common.sh to host shared function
  selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
  selftests/damon/sysfs.py: test non-default parameters runtime commit
  selftests/damon/sysfs.py: generalize DAMON context commit assertion
  selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
  selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
  selftests/damon/sysfs.py: test DAMOS filters commitment
  selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
  selftests/damon/sysfs.py: test DAMOS destinations commitment
  ...
</content>
</entry>
<entry>
<title>Merge tag 'powerpc-6.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2025-07-30T03:28:38Z</updated>
<author>
<name>Linus Torvalds</name>
</author>
<published>2025-07-30T03:28:38Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=5f5c9952b33cb4e8d25c70ef29f7a45cd26b6a9b'/>
<id>urn:sha1:5f5c9952b33cb4e8d25c70ef29f7a45cd26b6a9b</id>
<content type='text'>
Pull powerpc updates from Madhavan Srinivasan:

 - CONFIG_HZ changes to move the base_slice from 10ms to 1ms

 - Patchset to move some of the mutex handling to lock guard

 - Expose secvars relevant to the key management mode

 - Misc cleanups and fixes

Thanks to Ankit Chauhan, Christophe Leroy, Donet Tom, Gautam Menghani,
Haren Myneni, Johan Korsnes, Madadi Vineeth Reddy, Paul Mackerras,
Shrikanth Hegde, Srish Srinivasan, Thomas Fourier, Thomas Huth, Thomas
Weißschuh, Souradeep, Amit Machhiwal, R Nageswara Sastry, Venkat Rao
Bagalkote, Andrew Donnellan, Greg Kroah-Hartman, Mimi Zohar, Mukesh
Kumar Chaurasiya, Nayna Jain, Ritesh Harjani (IBM), Sourabh Jain, Srikar
Dronamraju, Stefan Berger, Tyrel Datwyler, and Kowshik Jois.

* tag 'powerpc-6.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (23 commits)
  arch/powerpc: Remove .interp section in vmlinux
  powerpc: Drop GPL boilerplate text with obsolete FSF address
  powerpc: Don't use %pK through printk
  arch: powerpc: defconfig: Drop obsolete CONFIG_NET_CLS_TCINDEX
  misc: ocxl: Replace scnprintf() with sysfs_emit() in sysfs show functions
  integrity/platform_certs: Allow loading of keys in the static key management mode
  powerpc/secvar: Expose secvars relevant to the key management mode
  powerpc/pseries: Correct secvar format representation for static key management
  (powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer
  powerpc: floppy: Add missing checks after DMA map
  book3s64/radix : Optimize vmemmap start alignment
  book3s64/radix : Handle error conditions properly in radix_vmemmap_populate
  powerpc/pseries/dlpar: Search DRC index from ibm,drc-indexes for IO add
  KVM: PPC: Book3S HV: Add H_VIRT mapping for tracing exits
  powerpc: sysdev: use lock guard for mutex
  powerpc: powernv: ocxl: use lock guard for mutex
  powerpc: book3s: vas: use lock guard for mutex
  powerpc: fadump: use lock guard for mutex
  powerpc: rtas: use lock guard for mutex
  powerpc: eeh: use lock guard for mutex
  ...
</content>
</entry>
<entry>
<title>powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section</title>
<updated>2025-07-22T04:42:21Z</updated>
<author>
<name>Ritesh Harjani (IBM)</name>
</author>
<published>2025-07-17T23:25:13Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=645d1b666498ef0d2c44c434a609b5560e9dc401'/>
<id>urn:sha1:645d1b666498ef0d2c44c434a609b5560e9dc401</id>
<content type='text'>
Move a few kfence and debug_pagealloc related functions in hash_utils.c
and radix_pgtable.c to __init sections since these are only invoked once
by an __init function during system initialization.

i.e.
- hash_debug_pagealloc_alloc_slots()
- hash_kfence_alloc_pool()
- hash_kfence_map_pool()
  The above 3 functions only gets called by __init htab_initialize().

- alloc_kfence_pool()
- map_kfence_pool()
  The above 2 functions only gets called by __init radix_init_pgtable()

This should also help fix warning msgs like:

&gt;&gt; WARNING: modpost: vmlinux: section mismatch in reference:
hash_debug_pagealloc_alloc_slots+0xb0 (section: .text) -&gt;
memblock_alloc_try_nid (section: .init.text)

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202504190552.mnFGs5sj-lkp@intel.com/
Signed-off-by: Ritesh Harjani (IBM) &lt;ritesh.list@gmail.com&gt;
Link: https://lore.kernel.org/r/20250717232519.2984886-8-kees@kernel.org
Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</content>
</entry>
<entry>
<title>Add a new optional ",cma" suffix to the crashkernel= command line option</title>
<updated>2025-07-20T02:08:22Z</updated>
<author>
<name>Jiri Bohac</name>
</author>
<published>2025-06-12T10:13:21Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=35c18f2933c596b4fd6a98baee36f3137d133a5f'/>
<id>urn:sha1:35c18f2933c596b4fd6a98baee36f3137d133a5f</id>
<content type='text'>
Patch series "kdump: crashkernel reservation from CMA", v5.

This series implements a way to reserve additional crash kernel memory
using CMA.

Currently, all the memory for the crash kernel is not usable by the 1st
(production) kernel.  It is also unmapped so that it can't be corrupted by
the fault that will eventually trigger the crash.  This makes sense for
the memory actually used by the kexec-loaded crash kernel image and initrd
and the data prepared during the load (vmcoreinfo, ...).  However, the
reserved space needs to be much larger than that to provide enough
run-time memory for the crash kernel and the kdump userspace.  Estimating
the amount of memory to reserve is difficult.  Being too careful makes
kdump likely to end in OOM, being too generous takes even more memory from
the production system.  Also, the reservation only allows reserving a
single contiguous block (or two with the "low" suffix).  I've seen systems
where this fails because the physical memory is fragmented.

By reserving additional crashkernel memory from CMA, the main crashkernel
reservation can be just large enough to fit the kernel and initrd image,
minimizing the memory taken away from the production system.  Most of the
run-time memory for the crash kernel will be memory previously available
to userspace in the production system.  As this memory is no longer
wasted, the reservation can be done with a generous margin, making kdump
more reliable.  Kernel memory that we need to preserve for dumping is
normally not allocated from CMA, unless it is explicitly allocated as
movable.  Currently this is only the case for memory ballooning and zswap.
Such movable memory will be missing from the vmcore.  User data is
typically not dumped by makedumpfile.  When dumping of user data is
intended this new CMA reservation cannot be used.

There are five patches in this series:

The first adds a new ",cma" suffix to the recenly introduced generic
crashkernel parsing code.  parse_crashkernel() takes one more argument to
store the cma reservation size.

The second patch implements reserve_crashkernel_cma() which performs the
reservation.  If the requested size is not available in a single range,
multiple smaller ranges will be reserved.

The third patch updates Documentation/, explicitly mentioning the
potential DMA corruption of the CMA-reserved memory.

The fourth patch adds a short delay before booting the kdump kernel,
allowing pending DMA transfers to finish.

The fifth patch enables the functionality for x86 as a proof of
concept. There are just three things every arch needs to do:
- call reserve_crashkernel_cma()
- include the CMA-reserved ranges in the physical memory map
- exclude the CMA-reserved ranges from the memory available
  through /proc/vmcore by excluding them from the vmcoreinfo
  PT_LOAD ranges.

Adding other architectures is easy and I can do that as soon as this
series is merged.

With this series applied, specifying
	crashkernel=100M craskhernel=1G,cma
on the command line will make a standard crashkernel reservation
of 100M, where kexec will load the kernel and initrd.

An additional 1G will be reserved from CMA, still usable by the production
system.  The crash kernel will have 1.1G memory available.  The 100M can
be reliably predicted based on the size of the kernel and initrd.

The new cma suffix is completely optional. When no
crashkernel=size,cma is specified, everything works as before.


This patch (of 5):

Add a new cma_size parameter to parse_crashkernel().  When not NULL, call
__parse_crashkernel to parse the CMA reservation size from
"crashkernel=size,cma" and store it in cma_size.

Set cma_size to NULL in all calls to parse_crashkernel().

Link: https://lkml.kernel.org/r/aEqnxxfLZMllMC8I@dwarf.suse.cz
Link: https://lkml.kernel.org/r/aEqoQckgoTQNULnh@dwarf.suse.cz
Signed-off-by: Jiri Bohac &lt;jbohac@suse.cz&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Dave Young &lt;dyoung@redhat.com&gt;
Cc: Donald Dutile &lt;ddutile@redhat.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Philipp Rudo &lt;prudo@redhat.com&gt;
Cc: Pingfan Liu &lt;piliu@redhat.com&gt;
Cc: Tao Liu &lt;ltao@redhat.com&gt;
Cc: Vivek Goyal &lt;vgoyal@redhat.com&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>powerpc: remove checks for devmap pages and PMDs/PUDs</title>
<updated>2025-07-10T05:42:17Z</updated>
<author>
<name>Alistair Popple</name>
</author>
<published>2025-06-19T08:58:01Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=bea0cc7cf4a51e8d3a0042212df3b83b49df58a7'/>
<id>urn:sha1:bea0cc7cf4a51e8d3a0042212df3b83b49df58a7</id>
<content type='text'>
PFN_DEV no longer exists.  This means no devmap PMDs or PUDs will be
created, so checking for them is redundant.  Instead mappings of pages
that would have previously returned true for pXd_devmap() will return true
for pXd_trans_huge()

Link: https://lkml.kernel.org/r/31f63cc8dd518f9e2ec300681fe302eb4adf49b4.1750323463.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple &lt;apopple@nvidia.com&gt;
Reviewed-by: Jason Gunthorpe &lt;jgg@nvidia.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Balbir Singh &lt;balbirs@nvidia.com&gt;
Cc: Björn Töpel &lt;bjorn@kernel.org&gt;
Cc: Björn Töpel &lt;bjorn@rivosinc.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Chunyan Zhang &lt;zhang.lyra@gmail.com&gt;
Cc: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Deepak Gupta &lt;debug@rivosinc.com&gt;
Cc: Gerald Schaefer &lt;gerald.schaefer@linux.ibm.com&gt;
Cc: Inki Dae &lt;m.szyprowski@samsung.com&gt;
Cc: John Groves &lt;john@groves.net&gt;
Cc: John Hubbard &lt;jhubbard@nvidia.com&gt;
Cc: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm: change vm_get_page_prot() to accept vm_flags_t argument</title>
<updated>2025-07-10T05:42:13Z</updated>
<author>
<name>Lorenzo Stoakes</name>
</author>
<published>2025-06-18T19:42:52Z</published>
<link rel='alternate' type='text/html' href='https://git.0xinfinity.dev/distro/kernel.git/commit/?id=78ddaa358ec4cdd60bd0e243ced1c83a52c30241'/>
<id>urn:sha1:78ddaa358ec4cdd60bd0e243ced1c83a52c30241</id>
<content type='text'>
Patch series "use vm_flags_t consistently".

The VMA flags field vma-&gt;vm_flags is of type vm_flags_t.  Right now this
is exactly equivalent to unsigned long, but it should not be assumed to
be.

Much code that references vma-&gt;vm_flags already correctly uses vm_flags_t,
but a fairly large chunk of code simply uses unsigned long and assumes
that the two are equivalent.

This series corrects that and has us use vm_flags_t consistently.

This series is motivated by the desire to, in a future series, adjust
vm_flags_t to be a u64 regardless of whether the kernel is 32-bit or
64-bit in order to deal with the VMA flag exhaustion issue and avoid all
the various problems that arise from it (being unable to use certain
features in 32-bit, being unable to add new flags except for 64-bit, etc.)

This is therefore a critical first step towards that goal.  At any rate,
using the correct type is of value regardless.

We additionally take the opportunity to refer to VMA flags as vm_flags
where possible to make clear what we're referring to.

Overall, this series does not introduce any functional change.


This patch (of 3):

We abstract the type of the VMA flags to vm_flags_t, however in may places
it is simply assumed this is unsigned long, which is simply incorrect.

At the moment this is simply an incongruity, however in future we plan to
change this type and therefore this change is a critical requirement for
doing so.

Overall, this patch does not introduce any functional change.

[lorenzo.stoakes@oracle.com: add missing vm_get_page_prot() instance, remove include]
  Link: https://lkml.kernel.org/r/552f88e1-2df8-4e95-92b8-812f7c8db829@lucifer.local
Link: https://lkml.kernel.org/r/cover.1750274467.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/a12769720a2743f235643b158c4f4f0a9911daf0.1750274467.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Acked-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Acked-by: Christian Brauner &lt;brauner@kernel.org&gt;
Reviewed-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Reviewed-by: Oscar Salvador &lt;osalvador@suse.de&gt;
Reviewed-by: Pedro Falcato &lt;pfalcato@suse.de&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;	[arm64]
Acked-by: Zi Yan &lt;ziy@nvidia.com&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Reviewed-by: Anshuman Khandual &lt;anshuman.khandual@arm.com&gt;
Cc: Liam R. Howlett &lt;Liam.Howlett@oracle.com&gt;
Cc: Lorenzo Stoakes &lt;lorenzo.stoakes@oracle.com&gt;
Cc: Jann Horn &lt;jannh@google.com&gt;
Cc: Kees Cook &lt;kees@kernel.org&gt;
Cc: Jan Kara &lt;jack@suse.cz&gt;
Cc: Jarkko Sakkinen &lt;jarkko@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
</feed>
