<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/init/main.c, branch v6.1.12</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.12</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.12'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2022-10-12T18:00:22+00:00</updated>
<entry>
<title>Merge tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-12T18:00:22+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-12T18:00:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=676cb4957396411fdb7aba906d5f950fc3de7cc9'/>
<id>urn:sha1:676cb4957396411fdb7aba906d5f950fc3de7cc9</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:

 - hfs and hfsplus kmap API modernization (Fabio Francesco)

 - make crash-kexec work properly when invoked from an NMI-time panic
   (Valentin Schneider)

 - ntfs bugfixes (Hawkins Jiawei)

 - improve IPC msg scalability by replacing atomic_t's with percpu
   counters (Jiebin Sun)

 - nilfs2 cleanups (Minghao Chi)

 - lots of other single patches all over the tree!

* tag 'mm-nonmm-stable-2022-10-11' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (71 commits)
  include/linux/entry-common.h: remove has_signal comment of arch_do_signal_or_restart() prototype
  proc: test how it holds up with mapping'less process
  mailmap: update Frank Rowand email address
  ia64: mca: use strscpy() is more robust and safer
  init/Kconfig: fix unmet direct dependencies
  ia64: update config files
  nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
  fork: remove duplicate included header files
  init/main.c: remove unnecessary (void*) conversions
  proc: mark more files as permanent
  nilfs2: remove the unneeded result variable
  nilfs2: delete unnecessary checks before brelse()
  checkpatch: warn for non-standard fixes tag style
  usr/gen_init_cpio.c: remove unnecessary -1 values from int file
  ipc/msg: mitigate the lock contention with percpu counter
  percpu: add percpu_counter_add_local and percpu_counter_sub_local
  fs/ocfs2: fix repeated words in comments
  relay: use kvcalloc to alloc page array in relay_alloc_page_array
  proc: make config PROC_CHILDREN depend on PROC_FS
  fs: uninline inode_maybe_inc_iversion()
  ...
</content>
</entry>
<entry>
<title>Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2022-10-11T00:53:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-10-11T00:53:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=27bc50fc90647bbf7b734c3fc306a5e61350da53'/>
<id>urn:sha1:27bc50fc90647bbf7b734c3fc306a5e61350da53</id>
<content type='text'>
Pull MM updates from Andrew Morton:

 - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
   linux-next for a couple of months without, to my knowledge, any
   negative reports (or any positive ones, come to that).

 - Also the Maple Tree from Liam Howlett. An overlapping range-based
   tree for vmas. It it apparently slightly more efficient in its own
   right, but is mainly targeted at enabling work to reduce mmap_lock
   contention.

   Liam has identified a number of other tree users in the kernel which
   could be beneficially onverted to mapletrees.

   Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat
   at [1]. This has yet to be addressed due to Liam's unfortunately
   timed vacation. He is now back and we'll get this fixed up.

 - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses
   clang-generated instrumentation to detect used-unintialized bugs down
   to the single bit level.

   KMSAN keeps finding bugs. New ones, as well as the legacy ones.

 - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of
   memory into THPs.

 - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to
   support file/shmem-backed pages.

 - userfaultfd updates from Axel Rasmussen

 - zsmalloc cleanups from Alexey Romanov

 - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and
   memory-failure

 - Huang Ying adds enhancements to NUMA balancing memory tiering mode's
   page promotion, with a new way of detecting hot pages.

 - memcg updates from Shakeel Butt: charging optimizations and reduced
   memory consumption.

 - memcg cleanups from Kairui Song.

 - memcg fixes and cleanups from Johannes Weiner.

 - Vishal Moola provides more folio conversions

 - Zhang Yi removed ll_rw_block() :(

 - migration enhancements from Peter Xu

 - migration error-path bugfixes from Huang Ying

 - Aneesh Kumar added ability for a device driver to alter the memory
   tiering promotion paths. For optimizations by PMEM drivers, DRM
   drivers, etc.

 - vma merging improvements from Jakub Matěn.

 - NUMA hinting cleanups from David Hildenbrand.

 - xu xin added aditional userspace visibility into KSM merging
   activity.

 - THP &amp; KSM code consolidation from Qi Zheng.

 - more folio work from Matthew Wilcox.

 - KASAN updates from Andrey Konovalov.

 - DAMON cleanups from Kaixu Xia.

 - DAMON work from SeongJae Park: fixes, cleanups.

 - hugetlb sysfs cleanups from Muchun Song.

 - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core.

Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1]

* tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits)
  hugetlb: allocate vma lock for all sharable vmas
  hugetlb: take hugetlb vma_lock when clearing vma_lock-&gt;vma pointer
  hugetlb: fix vma lock handling during split vma and range unmapping
  mglru: mm/vmscan.c: fix imprecise comments
  mm/mglru: don't sync disk for each aging cycle
  mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol
  mm: memcontrol: use do_memsw_account() in a few more places
  mm: memcontrol: deprecate swapaccounting=0 mode
  mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled
  mm/secretmem: remove reduntant return value
  mm/hugetlb: add available_huge_pages() func
  mm: remove unused inline functions from include/linux/mm_inline.h
  selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory
  selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd
  selftests/vm: add thp collapse shmem testing
  selftests/vm: add thp collapse file and tmpfs testing
  selftests/vm: modularize thp collapse memory operations
  selftests/vm: dedup THP helpers
  mm/khugepaged: add tracepoint to hpage_collapse_scan_file()
  mm/madvise: add file and shmem support to MADV_COLLAPSE
  ...
</content>
</entry>
<entry>
<title>init/main.c: remove unnecessary (void*) conversions</title>
<updated>2022-10-03T21:21:45+00:00</updated>
<author>
<name>Zhou jie</name>
<email>zhoujie@nfschina.com</email>
</author>
<published>2022-09-28T01:45:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=374d6cda7946431611c41cbb6e75dc4a25727ea8'/>
<id>urn:sha1:374d6cda7946431611c41cbb6e75dc4a25727ea8</id>
<content type='text'>
The void pointer object can be directly assigned to different structure
objects, it does not need to be cast.

Link: https://lkml.kernel.org/r/20220928014539.11046-1-zhoujie@nfschina.com
Signed-off-by: Zhou jie &lt;zhoujie@nfschina.com&gt;
Reviewed-by: Andrew Halaney &lt;ahalaney@redhat.com&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>init: kmsan: call KMSAN initialization routines</title>
<updated>2022-10-03T21:03:21+00:00</updated>
<author>
<name>Alexander Potapenko</name>
<email>glider@google.com</email>
</author>
<published>2022-09-15T15:03:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=3c206509826094e85ead0b056f484db96829248d'/>
<id>urn:sha1:3c206509826094e85ead0b056f484db96829248d</id>
<content type='text'>
kmsan_init_shadow() scans the mappings created at boot time and creates
metadata pages for those mappings.

When the memblock allocator returns pages to pagealloc, we reserve 2/3 of
those pages and use them as metadata for the remaining 1/3.  Once KMSAN
starts, every page allocated by pagealloc has its associated shadow and
origin pages.

kmsan_initialize() initializes the bookkeeping for init_task and enables
KMSAN.

Link: https://lkml.kernel.org/r/20220915150417.722975-18-glider@google.com
Signed-off-by: Alexander Potapenko &lt;glider@google.com&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Andrey Konovalov &lt;andreyknvl@gmail.com&gt;
Cc: Andrey Konovalov &lt;andreyknvl@google.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Eric Biggers &lt;ebiggers@google.com&gt;
Cc: Eric Biggers &lt;ebiggers@kernel.org&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: Ilya Leoshkevich &lt;iii@linux.ibm.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Marco Elver &lt;elver@google.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Cc: Pekka Enberg &lt;penberg@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Vegard Nossum &lt;vegard.nossum@oracle.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>random: split initialization into early step and later step</title>
<updated>2022-09-29T19:36:27+00:00</updated>
<author>
<name>Jason A. Donenfeld</name>
<email>Jason@zx2c4.com</email>
</author>
<published>2022-09-26T15:43:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f62384995e4cb7703e5295779c44135c5311770d'/>
<id>urn:sha1:f62384995e4cb7703e5295779c44135c5311770d</id>
<content type='text'>
The full RNG initialization relies on some timestamps, made possible
with initialization functions like time_init() and timekeeping_init().
However, these are only available rather late in initialization.
Meanwhile, other things, such as memory allocator functions, make use of
the RNG much earlier.

So split RNG initialization into two phases. We can provide arch
randomness very early on, and then later, after timekeeping and such are
available, initialize the rest.

This ensures that, for example, slabs are properly randomized if RDRAND
is available. Without this, CONFIG_SLAB_FREELIST_RANDOM=y loses a degree
of its security, because its random seed is potentially deterministic,
since it hasn't yet incorporated RDRAND. It also makes it possible to
use a better seed in kfence, which currently relies on only the cycle
counter.

Another positive consequence is that on systems with RDRAND, running
with CONFIG_WARN_ALL_UNSEEDED_RANDOM=y results in no warnings at all.

One subtle side effect of this change is that on systems with no RDRAND,
RDTSC is now only queried by random_init() once, committing the moment
of the function call, instead of multiple times as before. This is
intentional, as the multiple RDTSCs in a loop before weren't
accomplishing very much, with jitter being better provided by
try_to_generate_entropy(). Plus, filling blocks with RDTSC is still
being done in extract_entropy(), which is necessarily called before
random bytes are served anyway.

Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Dominik Brodowski &lt;linux@dominikbrodowski.net&gt;
Signed-off-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
</content>
</entry>
<entry>
<title>Maple Tree: add new data structure</title>
<updated>2022-09-27T02:46:13+00:00</updated>
<author>
<name>Liam R. Howlett</name>
<email>Liam.Howlett@Oracle.com</email>
</author>
<published>2022-09-06T19:48:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=54a611b605901c7d5d05b6b8f5d04a6ceb0962aa'/>
<id>urn:sha1:54a611b605901c7d5d05b6b8f5d04a6ceb0962aa</id>
<content type='text'>
Patch series "Introducing the Maple Tree"

The maple tree is an RCU-safe range based B-tree designed to use modern
processor cache efficiently.  There are a number of places in the kernel
that a non-overlapping range-based tree would be beneficial, especially
one with a simple interface.  If you use an rbtree with other data
structures to improve performance or an interval tree to track
non-overlapping ranges, then this is for you.

The tree has a branching factor of 10 for non-leaf nodes and 16 for leaf
nodes.  With the increased branching factor, it is significantly shorter
than the rbtree so it has fewer cache misses.  The removal of the linked
list between subsequent entries also reduces the cache misses and the need
to pull in the previous and next VMA during many tree alterations.

The first user that is covered in this patch set is the vm_area_struct,
where three data structures are replaced by the maple tree: the augmented
rbtree, the vma cache, and the linked list of VMAs in the mm_struct.  The
long term goal is to reduce or remove the mmap_lock contention.

The plan is to get to the point where we use the maple tree in RCU mode.
Readers will not block for writers.  A single write operation will be
allowed at a time.  A reader re-walks if stale data is encountered.  VMAs
would be RCU enabled and this mode would be entered once multiple tasks
are using the mm_struct.

Davidlor said

: Yes I like the maple tree, and at this stage I don't think we can ask for
: more from this series wrt the MM - albeit there seems to still be some
: folks reporting breakage.  Fundamentally I see Liam's work to (re)move
: complexity out of the MM (not to say that the actual maple tree is not
: complex) by consolidating the three complimentary data structures very
: much worth it considering performance does not take a hit.  This was very
: much a turn off with the range locking approach, which worst case scenario
: incurred in prohibitive overhead.  Also as Liam and Matthew have
: mentioned, RCU opens up a lot of nice performance opportunities, and in
: addition academia[1] has shown outstanding scalability of address spaces
: with the foundation of replacing the locked rbtree with RCU aware trees.

A similar work has been discovered in the academic press

	https://pdos.csail.mit.edu/papers/rcuvm:asplos12.pdf

Sheer coincidence.  We designed our tree with the intention of solving the
hardest problem first.  Upon settling on a b-tree variant and a rough
outline, we researched ranged based b-trees and RCU b-trees and did find
that article.  So it was nice to find reassurances that we were on the
right path, but our design choice of using ranges made that paper unusable
for us.

This patch (of 70):

The maple tree is an RCU-safe range based B-tree designed to use modern
processor cache efficiently.  There are a number of places in the kernel
that a non-overlapping range-based tree would be beneficial, especially
one with a simple interface.  If you use an rbtree with other data
structures to improve performance or an interval tree to track
non-overlapping ranges, then this is for you.

The tree has a branching factor of 10 for non-leaf nodes and 16 for leaf
nodes.  With the increased branching factor, it is significantly shorter
than the rbtree so it has fewer cache misses.  The removal of the linked
list between subsequent entries also reduces the cache misses and the need
to pull in the previous and next VMA during many tree alterations.

The first user that is covered in this patch set is the vm_area_struct,
where three data structures are replaced by the maple tree: the augmented
rbtree, the vma cache, and the linked list of VMAs in the mm_struct.  The
long term goal is to reduce or remove the mmap_lock contention.

The plan is to get to the point where we use the maple tree in RCU mode.
Readers will not block for writers.  A single write operation will be
allowed at a time.  A reader re-walks if stale data is encountered.  VMAs
would be RCU enabled and this mode would be entered once multiple tasks
are using the mm_struct.

There is additional BUG_ON() calls added within the tree, most of which
are in debug code.  These will be replaced with a WARN_ON() call in the
future.  There is also additional BUG_ON() calls within the code which
will also be reduced in number at a later date.  These exist to catch
things such as out-of-range accesses which would crash anyways.

Link: https://lkml.kernel.org/r/20220906194824.2110408-1-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20220906194824.2110408-2-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett &lt;Liam.Howlett@oracle.com&gt;
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Tested-by: David Howells &lt;dhowells@redhat.com&gt;
Tested-by: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Tested-by: Yu Zhao &lt;yuzhao@google.com&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: David Hildenbrand &lt;david@redhat.com&gt;
Cc: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: SeongJae Park &lt;sj@kernel.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>init: move from strlcpy with unused retval to strscpy</title>
<updated>2022-09-12T04:55:10+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2022-08-18T21:01:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=a1d3a6d9f243797d1bcaa0ca14c03396bc302ca6'/>
<id>urn:sha1:a1d3a6d9f243797d1bcaa0ca14c03396bc302ca6</id>
<content type='text'>
Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818210200.8203-1-wsa+renesas@sang-engineering.com
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>page_ext: introduce boot parameter 'early_page_ext'</title>
<updated>2022-09-12T03:26:02+00:00</updated>
<author>
<name>Li Zhe</name>
<email>lizhe.67@bytedance.com</email>
</author>
<published>2022-08-25T10:27:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c4f20f1479c456d9dd1c1e6d8bf956a25de742dc'/>
<id>urn:sha1:c4f20f1479c456d9dd1c1e6d8bf956a25de742dc</id>
<content type='text'>
In commit 2f1ee0913ce5 ("Revert "mm: use early_pfn_to_nid in
page_ext_init""), we call page_ext_init() after page_alloc_init_late() to
avoid some panic problem.  It seems that we cannot track early page
allocations in current kernel even if page structure has been initialized
early.

This patch introduces a new boot parameter 'early_page_ext' to resolve
this problem.  If we pass it to the kernel, page_ext_init() will be moved
up and the feature 'deferred initialization of struct pages' will be
disabled to initialize the page allocator early and prevent the panic
problem above.  It can help us to catch early page allocations.  This is
useful especially when we find that the free memory value is not the same
right after different kernel booting.

[akpm@linux-foundation.org: fix section issue by removing __meminitdata]
Link: https://lkml.kernel.org/r/20220825102714.669-1-lizhe.67@bytedance.com
Signed-off-by: Li Zhe &lt;lizhe.67@bytedance.com&gt;
Suggested-by: Michal Hocko &lt;mhocko@suse.com&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.com&gt;
Acked-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Mark-PK Tsai &lt;mark-pk.tsai@mediatek.com&gt;
Cc: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>arm64: fix rodata=full</title>
<updated>2022-08-23T10:02:02+00:00</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2022-08-17T15:40:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=2e8cff0a0eee87b27f0cf87ad8310eb41b5886ab'/>
<id>urn:sha1:2e8cff0a0eee87b27f0cf87ad8310eb41b5886ab</id>
<content type='text'>
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 &lt;mark.rutland@arm.com&gt;
Cc: Andy Shevchenko &lt;andy.shevchenko@gmail.com&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Jagdish Gediya &lt;jvgediya@linux.ibm.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Reviewed-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Link: https://lore.kernel.org/r/20220817154022.3974645-1-mark.rutland@arm.com
Signed-off-by: Will Deacon &lt;will@kernel.org&gt;
</content>
</entry>
<entry>
<title>stack: Declare {randomize_,}kstack_offset to fix Sparse warnings</title>
<updated>2022-07-02T01:01:47+00:00</updated>
<author>
<name>GONG, Ruiqi</name>
<email>gongruiqi1@huawei.com</email>
</author>
<published>2022-06-29T06:04:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=375561bd6195a31bf4c109732bd538cb97a941f4'/>
<id>urn:sha1:375561bd6195a31bf4c109732bd538cb97a941f4</id>
<content type='text'>
Fix the following Sparse warnings that got noticed when the PPC-dev
patchwork was checking another patch (see the link below):

init/main.c:862:1: warning: symbol 'randomize_kstack_offset' was not declared. Should it be static?
init/main.c:864:1: warning: symbol 'kstack_offset' was not declared. Should it be static?

Which in fact are triggered on all architectures that have
HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET support (for instances x86, arm64
etc).

Link: https://lore.kernel.org/lkml/e7b0d68b-914d-7283-827c-101988923929@huawei.com/T/#m49b2d4490121445ce4bf7653500aba59eefcb67f
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Xiu Jianfeng &lt;xiujianfeng@huawei.com&gt;
Signed-off-by: GONG, Ruiqi &lt;gongruiqi1@huawei.com&gt;
Reviewed-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Fixes: 39218ff4c625 ("stack: Optionally randomize kernel stack offset each syscall")
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Link: https://lore.kernel.org/r/20220629060423.2515693-1-gongruiqi1@huawei.com
</content>
</entry>
</feed>
