History log of /openbmc/linux/mm/slab.c (Results 1 – 25 of 2971)
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Revision tags: v6.6.67, v6.6.66, v6.6.65, v6.6.64, v6.6.63, v6.6.62, v6.6.61, v6.6.60, v6.6.59, v6.6.58, v6.6.57, v6.6.56, v6.6.55, v6.6.54, v6.6.53, v6.6.52, v6.6.51, v6.6.50, v6.6.49, v6.6.48, v6.6.47, v6.6.46, v6.6.45, v6.6.44, v6.6.43, v6.6.42, v6.6.41, v6.6.40, v6.6.39, v6.6.38, v6.6.37, v6.6.36, v6.6.35, v6.6.34, v6.6.33, v6.6.32, v6.6.31, v6.6.30, v6.6.29, v6.6.28, v6.6.27, v6.6.26, v6.6.25, v6.6.24, v6.6.23, v6.6.16, v6.6.15, v6.6.14, v6.6.13, v6.6.12, v6.6.11, v6.6.10, v6.6.9, v6.6.8, v6.6.7, v6.6.6, v6.6.5, v6.6.4, v6.6.3, v6.6.2, v6.5.11, v6.6.1, v6.5.10, v6.6, v6.5.9, v6.5.8, v6.5.7, v6.5.6, v6.5.5, v6.5.4, v6.5.3
# c900529f 12-Sep-2023 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-fixes into drm-misc-fixes

Forwarding to v6.6-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


Revision tags: v6.5.2, v6.1.51, v6.5.1
# 1ac731c5 30-Aug-2023 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.


Revision tags: v6.1.50
# 651a00bc 29-Aug-2023 Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'slab-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:
"This happens to be a small one (due to summer I guess), and all
hard

Merge tag 'slab-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:
"This happens to be a small one (due to summer I guess), and all
hardening related:

- Randomized kmalloc caches, by GONG, Ruiqi.

A new opt-in hardening feature to make heap spraying harder. It
creates multiple (16) copies of kmalloc caches, reducing the chance
of an attacker-controllable allocation site to land in the same
slab as e.g. an allocation site with use-after-free vulnerability.

The selection of the copy is derived from the allocation site
address, including a per-boot random seed.

- Stronger typing for hardened freelists in SLUB, by Jann Horn

Introduces a custom type for hardened freelist entries instead of
"void *" as those are not directly dereferencable. While reviewing
this, I've noticed opportunities for further cleanups in that code
and added those on top"

* tag 'slab-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
Randomized slab caches for kmalloc()
mm/slub: remove freelist_dereference()
mm/slub: remove redundant kasan_reset_tag() from freelist_ptr calculations
mm/slub: refactor freelist to use custom type

show more ...


Revision tags: v6.5, v6.1.49, v6.1.48, v6.1.46, v6.1.45, v6.1.44, v6.1.43, v6.1.42, v6.1.41, v6.1.40, v6.1.39
# 3d053e80 18-Jul-2023 Vlastimil Babka <vbabka@suse.cz>

Merge branch 'slab/for-6.6/random_kmalloc' into slab/for-next

Merge the new hardening feature to make heap spraying harder, by GONG,
Ruiqi. It creates multiple (16) copies of kmalloc caches, reducin

Merge branch 'slab/for-6.6/random_kmalloc' into slab/for-next

Merge the new hardening feature to make heap spraying harder, by GONG,
Ruiqi. It creates multiple (16) copies of kmalloc caches, reducing the
chance of an attacker-controllable allocation site to land in the same
slab as e.g. an allocation site with use-after-free vulnerability. The
selection of the copy is derived from the allocation site address,
including a per-boot random seed.

In line with SLAB deprecation, this is a SLUB only feature, incompatible
with SLUB_TINY due to the memory overhead of the extra cache copies.

show more ...


# 2612e3bb 07-Aug-2023 Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo V

Merge drm/drm-next into drm-intel-next

Catching-up with drm-next and drm-intel-gt-next.
It will unblock a code refactor around the platform
definitions (names vs acronyms).

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

show more ...


# 9f771739 07-Aug-2023 Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/1

Merge drm/drm-next into drm-intel-gt-next

Need to pull in b3e4aae612ec ("drm/i915/hdcp: Modify hdcp_gsc_message msg sending mechanism") as
a dependency for https://patchwork.freedesktop.org/series/121735/

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

show more ...


# 61b73694 24-Jul-2023 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-misc-next

Backmerging to get v6.5-rc2.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


# 3c615294 14-Jul-2023 GONG, Ruiqi <gongruiqi@huaweicloud.com>

Randomized slab caches for kmalloc()

When exploiting memory vulnerabilities, "heap spraying" is a common
technique targeting those related to dynamic memory allocation (i.e. the
"heap"), and it play

Randomized slab caches for kmalloc()

When exploiting memory vulnerabilities, "heap spraying" is a common
technique targeting those related to dynamic memory allocation (i.e. the
"heap"), and it plays an important role in a successful exploitation.
Basically, it is to overwrite the memory area of vulnerable object by
triggering allocation in other subsystems or modules and therefore
getting a reference to the targeted memory location. It's usable on
various types of vulnerablity including use after free (UAF), heap out-
of-bound write and etc.

There are (at least) two reasons why the heap can be sprayed: 1) generic
slab caches are shared among different subsystems and modules, and
2) dedicated slab caches could be merged with the generic ones.
Currently these two factors cannot be prevented at a low cost: the first
one is a widely used memory allocation mechanism, and shutting down slab
merging completely via `slub_nomerge` would be overkill.

To efficiently prevent heap spraying, we propose the following approach:
to create multiple copies of generic slab caches that will never be
merged, and random one of them will be used at allocation. The random
selection is based on the address of code that calls `kmalloc()`, which
means it is static at runtime (rather than dynamically determined at
each time of allocation, which could be bypassed by repeatedly spraying
in brute force). In other words, the randomness of cache selection will
be with respect to the code address rather than time, i.e. allocations
in different code paths would most likely pick different caches,
although kmalloc() at each place would use the same cache copy whenever
it is executed. In this way, the vulnerable object and memory allocated
in other subsystems and modules will (most probably) be on different
slab caches, which prevents the object from being sprayed.

Meanwhile, the static random selection is further enhanced with a
per-boot random seed, which prevents the attacker from finding a usable
kmalloc that happens to pick the same cache with the vulnerable
subsystem/module by analyzing the open source code. In other words, with
the per-boot seed, the random selection is static during each time the
system starts and runs, but not across different system startups.

The overhead of performance has been tested on a 40-core x86 server by
comparing the results of `perf bench all` between the kernels with and
without this patch based on the latest linux-next kernel, which shows
minor difference. A subset of benchmarks are listed below:

sched/ sched/ syscall/ mem/ mem/
messaging pipe basic memcpy memset
(sec) (sec) (sec) (GB/sec) (GB/sec)

control1 0.019 5.459 0.733 15.258789 51.398026
control2 0.019 5.439 0.730 16.009221 48.828125
control3 0.019 5.282 0.735 16.009221 48.828125
control_avg 0.019 5.393 0.733 15.759077 49.684759

experiment1 0.019 5.374 0.741 15.500992 46.502976
experiment2 0.019 5.440 0.746 16.276042 51.398026
experiment3 0.019 5.242 0.752 15.258789 51.398026
experiment_avg 0.019 5.352 0.746 15.678608 49.766343

The overhead of memory usage was measured by executing `free` after boot
on a QEMU VM with 1GB total memory, and as expected, it's positively
correlated with # of cache copies:

control 4 copies 8 copies 16 copies

total 969.8M 968.2M 968.2M 968.2M
used 20.0M 21.9M 24.1M 26.7M
free 936.9M 933.6M 931.4M 928.6M
available 932.2M 928.8M 926.6M 923.9M

Co-developed-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: GONG, Ruiqi <gongruiqi@huaweicloud.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Acked-by: Dennis Zhou <dennis@kernel.org> # percpu
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

show more ...


# 50501936 17-Jul-2023 Dmitry Torokhov <dmitry.torokhov@gmail.com>

Merge tag 'v6.4' into next

Sync up with mainline to bring in updates to shared infrastructure.


# 0791faeb 17-Jul-2023 Mark Brown <broonie@kernel.org>

ASoC: Merge v6.5-rc2

Get a similar baseline to my other branches, and fixes for people using
the branch.


# 2f98e686 11-Jul-2023 Maxime Ripard <mripard@kernel.org>

Merge v6.5-rc1 into drm-misc-fixes

Boris needs 6.5-rc1 in drm-misc-fixes to prevent a conflict.

Signed-off-by: Maxime Ripard <mripard@kernel.org>


Revision tags: v6.1.38, v6.1.37
# 44f10dbe 30-Jun-2023 Andrew Morton <akpm@linux-foundation.org>

Merge branch 'master' into mm-hotfixes-stable


# 632f54b4 29-Jun-2023 Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'slab-for-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

- SLAB deprecation:

Following the discussion at LSF/MM 2023 [1] an

Merge tag 'slab-for-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

- SLAB deprecation:

Following the discussion at LSF/MM 2023 [1] and no objections, the
SLAB allocator is deprecated by renaming the config option (to make
its users notice) to CONFIG_SLAB_DEPRECATED with updated help text.
SLUB should be used instead. Existing defconfigs with CONFIG_SLAB are
also updated.

- SLAB_NO_MERGE kmem_cache flag (Jesper Dangaard Brouer):

There are (very limited) cases where kmem_cache merging is
undesirable, and existing ways to prevent it are hacky. Introduce a
new flag to do that cleanly and convert the existing hacky users.
Btrfs plans to use this for debug kernel builds (that use case is
always fine), networking for performance reasons (that should be very
rare).

- Replace the usage of weak PRNGs (David Keisar Schmidt):

In addition to using stronger RNGs for the security related features,
the code is a bit cleaner.

- Misc code cleanups (SeongJae Parki, Xiongwei Song, Zhen Lei, and
zhaoxinchao)

Link: https://lwn.net/Articles/932201/ [1]

* tag 'slab-for-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab_common: use SLAB_NO_MERGE instead of negative refcount
mm/slab: break up RCU readers on SLAB_TYPESAFE_BY_RCU example code
mm/slab: add a missing semicolon on SLAB_TYPESAFE_BY_RCU example code
mm/slab_common: reduce an if statement in create_cache()
mm/slab: introduce kmem_cache flag SLAB_NO_MERGE
mm/slab: rename CONFIG_SLAB to CONFIG_SLAB_DEPRECATED
mm/slab: remove HAVE_HARDENED_USERCOPY_ALLOCATOR
mm/slab_common: Replace invocation of weak PRNG
mm/slab: Replace invocation of weak PRNG
slub: Don't read nr_slabs and total_objects directly
slub: Remove slabs_node() function
slub: Remove CONFIG_SMP defined check
slub: Put objects_show() into CONFIG_SLUB_DEBUG enabled block
slub: Correct the error code when slab_kset is NULL
mm/slab: correct return values in comment for _kmem_cache_create()

show more ...


# 6e17c6de 28-Jun-2023 Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:

- Yosry Ahmed brought back some cgroup v1 stats in OOM logs

-

Merge tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:

- Yosry Ahmed brought back some cgroup v1 stats in OOM logs

- Yosry has also eliminated cgroup's atomic rstat flushing

- Nhat Pham adds the new cachestat() syscall. It provides userspace
with the ability to query pagecache status - a similar concept to
mincore() but more powerful and with improved usability

- Mel Gorman provides more optimizations for compaction, reducing the
prevalence of page rescanning

- Lorenzo Stoakes has done some maintanance work on the
get_user_pages() interface

- Liam Howlett continues with cleanups and maintenance work to the
maple tree code. Peng Zhang also does some work on maple tree

- Johannes Weiner has done some cleanup work on the compaction code

- David Hildenbrand has contributed additional selftests for
get_user_pages()

- Thomas Gleixner has contributed some maintenance and optimization
work for the vmalloc code

- Baolin Wang has provided some compaction cleanups,

- SeongJae Park continues maintenance work on the DAMON code

- Huang Ying has done some maintenance on the swap code's usage of
device refcounting

- Christoph Hellwig has some cleanups for the filemap/directio code

- Ryan Roberts provides two patch series which yield some
rationalization of the kernel's access to pte entries - use the
provided APIs rather than open-coding accesses

- Lorenzo Stoakes has some fixes to the interaction between pagecache
and directio access to file mappings

- John Hubbard has a series of fixes to the MM selftesting code

- ZhangPeng continues the folio conversion campaign

- Hugh Dickins has been working on the pagetable handling code, mainly
with a view to reducing the load on the mmap_lock

- Catalin Marinas has reduced the arm64 kmalloc() minimum alignment
from 128 to 8

- Domenico Cerasuolo has improved the zswap reclaim mechanism by
reorganizing the LRU management

- Matthew Wilcox provides some fixups to make gfs2 work better with the
buffer_head code

- Vishal Moola also has done some folio conversion work

- Matthew Wilcox has removed the remnants of the pagevec code - their
functionality is migrated over to struct folio_batch

* tag 'mm-stable-2023-06-24-19-15' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (380 commits)
mm/hugetlb: remove hugetlb_set_page_subpool()
mm: nommu: correct the range of mmap_sem_read_lock in task_mem()
hugetlb: revert use of page_cache_next_miss()
Revert "page cache: fix page_cache_next/prev_miss off by one"
mm/vmscan: fix root proactive reclaim unthrottling unbalanced node
mm: memcg: rename and document global_reclaim()
mm: kill [add|del]_page_to_lru_list()
mm: compaction: convert to use a folio in isolate_migratepages_block()
mm: zswap: fix double invalidate with exclusive loads
mm: remove unnecessary pagevec includes
mm: remove references to pagevec
mm: rename invalidate_mapping_pagevec to mapping_try_invalidate
mm: remove struct pagevec
net: convert sunrpc from pagevec to folio_batch
i915: convert i915_gpu_error to use a folio_batch
pagevec: rename fbatch_count()
mm: remove check_move_unevictable_pages()
drm: convert drm_gem_put_pages() to use a folio_batch
i915: convert shmem_sg_free_table() to use a folio_batch
scatterlist: add sg_set_folio()
...

show more ...


Revision tags: v6.1.36
# e80b5003 27-Jun-2023 Jiri Kosina <jkosina@suse.cz>

Merge branch 'for-6.5/apple' into for-linus

- improved support for Keychron K8 keyboard (Lasse Brun)


Revision tags: v6.4, v6.1.35, v6.1.34
# 0c474d31 12-Jun-2023 Catalin Marinas <catalin.marinas@arm.com>

mm/slab: simplify create_kmalloc_cache() args and make it static

In the slab variant of kmem_cache_init(), call new_kmalloc_cache() instead
of initialising the kmalloc_caches array directly. With t

mm/slab: simplify create_kmalloc_cache() args and make it static

In the slab variant of kmem_cache_init(), call new_kmalloc_cache() instead
of initialising the kmalloc_caches array directly. With this,
create_kmalloc_cache() is now only called from new_kmalloc_cache() in the
same file, so make it static. In addition, the useroffset argument is
always 0 while usersize is the same as size. Remove them.

Link: https://lkml.kernel.org/r/20230612153201.554742-4-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...


# 7bc162d5 16-Jun-2023 Vlastimil Babka <vbabka@suse.cz>

Merge branches 'slab/for-6.5/prandom', 'slab/for-6.5/slab_no_merge' and 'slab/for-6.5/slab-deprecate' into slab/for-next

Merge the feature branches scheduled for 6.5:

- replace the usage of weak PR

Merge branches 'slab/for-6.5/prandom', 'slab/for-6.5/slab_no_merge' and 'slab/for-6.5/slab-deprecate' into slab/for-next

Merge the feature branches scheduled for 6.5:

- replace the usage of weak PRNGs, by David Keisar Schmidt

- introduce the SLAB_NO_MERGE kmem_cache flag, by Jesper Dangaard Brouer

- deprecate CONFIG_SLAB, with a planned removal, by myself

show more ...


# db6da59c 15-Jun-2023 Thomas Zimmermann <tzimmermann@suse.de>

Merge drm/drm-next into drm-misc-next-fixes

Backmerging to sync drm-misc-next-fixes with drm-misc-next.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>


# 03c60192 12-Jun-2023 Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patche

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patches depend on these helpers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

show more ...


Revision tags: v6.1.33
# 5c680050 06-Jun-2023 Miquel Raynal <miquel.raynal@bootlin.com>

Merge tag 'v6.4-rc4' into wpan-next/staging

Linux 6.4-rc4


# 9ff17e6b 05-Jun-2023 Tvrtko Ursulin <tvrtko.ursulin@intel.com>

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

show more ...


Revision tags: v6.1.32, v6.1.31, v6.1.30, v6.1.29, v6.1.28, v6.1.27, v6.1.26, v6.3, v6.1.25
# f7e466e9 16-Apr-2023 David Keisar Schmidt <david.keisarschm@mail.huji.ac.il>

mm/slab: Replace invocation of weak PRNG

The Slab allocator randomization uses the prandom_u32
PRNG. That was added to prevent attackers to obtain information on the heap
state, by randomizing the f

mm/slab: Replace invocation of weak PRNG

The Slab allocator randomization uses the prandom_u32
PRNG. That was added to prevent attackers to obtain information on the heap
state, by randomizing the freelists state.

However, this PRNG turned out to be weak, as noted in commit c51f8f88d705
To fix it, we have changed the invocation of prandom_u32_state to get_random_u32
to ensure the PRNG is strong. Since a modulo operation is applied right after that,
we used get_random_u32_below, to achieve uniformity.

In addition, we changed the freelist_init_state union to struct,
since the rnd_state inside which is used to store the state of prandom_u32,
is not needed anymore, since get_random_u32 maintains its own state.

Signed-off-by: David Keisar Schmidt <david.keisarschm@mail.huji.ac.il>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

show more ...


# 444f20c2 17-Apr-2023 zhaoxinchao <chrisxinchao@outlook.com>

mm/slab: correct return values in comment for _kmem_cache_create()

__kmem_cache_create() returns 0 on success and non-zero on failure.
The comment is wrong in two instances, so fix the first one and

mm/slab: correct return values in comment for _kmem_cache_create()

__kmem_cache_create() returns 0 on success and non-zero on failure.
The comment is wrong in two instances, so fix the first one and remove
the second one. Also make the comment non-doc, because it doesn't
describe an API function, but SLAB-specific implementation.

Signed-off-by: zhaoxinchao <chrisxinchao@outlook.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

show more ...


# 9c3a985f 17-May-2023 Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge drm/drm-next into drm-intel-next

Backmerge to get some hwmon dependencies.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>


# 50282fd5 12-May-2023 Maxime Ripard <maxime@cerno.tech>

Merge drm/drm-fixes into drm-misc-fixes

Let's bring 6.4-rc1 in drm-misc-fixes to start the new fix cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>


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