Commit Graph

10992 Commits

Author SHA1 Message Date
Liam R. Howlett (Oracle)
4e4fe9d727 maple_tree: avoid extra gap calculation
Prior to ending the ascension loop of larger operations like split,
rebalance, and spanning store the gap in the node had been calculated. 
Once the node is inserted into the tree, the gap is recalculated in
mas_update_gap().  This can be avoided by creating a helper for
mas_update_gap() that accepts the known gap value, which reduces the
operations required for gap updating path.

Link: https://lore.kernel.org/20260821192627.4085470-19-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:32 -07:00
Liam R. Howlett (Oracle)
f1681380b5 maple_tree: avoid mas_erase() and mtree_erase() failures
Failures to remove entries using the two APIs to erase the entries may
result in allocation failures.  The failures may go unnoticed and an
unexpected entry may remain.  Instead, fall back to retrying with
GFP_KERNEL | __GFP_NOFAIL so that the entry will be removed.

Link: https://lore.kernel.org/20260821192627.4085470-15-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:31 -07:00
Liam R. Howlett (Oracle)
3f06ef1f34 maple_tree: document that erase may use GFP_KERNEL for allocations
State that the mas_erase() and mtree_erase() functions may use GFP_KERNEL
on allocation retry.  Don't just depend on people reading the
documentation by adding a check that will warn of the use.

Link: https://lore.kernel.org/20260821192627.4085470-14-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Reviewed-by: Rik van Riel <riel@surriel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:31 -07:00
Liam R. Howlett (Oracle)
35f1342e5b maple_tree: catch race in mas_alloc_cyclic()
If mas_alloc_cyclic() is called during a low memory situation, it is
possible the lock may be dropped so reclaim can occur.  There is a window
where some other task may allocate the same id and cause the mas_insert()
to fail with -EEXIST.  In this scenario the function will return -EEXIST,
which is not expected.

Modifying the retry on mas_nomem() to re-search for a slot means that any
race with other writes will not matter as the lock will be held between
finding the index and writing the index.

Moving the flag logic avoids cases where the flag is modified on drop
lock/reacquire or when the write fails after clearing the flag.

No existing users are exposed to this issue.

Link: https://lore.kernel.org/20260821192627.4085470-13-liam@infradead.org
Fixes: 9b6713cc75 ("maple_tree: Add mtree_alloc_cyclic()")
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Reported-by: Chris Mason <clm@meta.com>
Reviewed-by: Chuck Lever <cel@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:30 -07:00
Liam R. Howlett (Oracle)
cf1f9bae5d maple_tree: add bulk parent set helper
Instead of calculating the parent pointer each time for a child, cache the
majority of the parent pointer and only change the slot per child.

Drop the mas_set_parent() function since the last user has been removed.

Testing on a tree containing 2048 entries of height 4 had an increased
gain of 3.51% on nodes tracking gaps.

Link: https://lore.kernel.org/20260821192627.4085470-12-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:30 -07:00
Liam R. Howlett (Oracle)
f0a3892cd7 maple_tree: micro optimisation of mas_wr_store_type()
Use three new local booleans instead of reading other structures.  This
has shown an increase of 0.62% on a 2048 entry tree of height 4.

Link: https://lore.kernel.org/20260821192627.4085470-11-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:30 -07:00
Liam R. Howlett (Oracle)
88f87f8812 maple_tree: optimise mas_wr_node_store() when not in rcu mode
Clearing the entire node on the stack is unnecessary since most of the
node will be overwritten anyways.  Just clear what isn't used after the
data is in place.

Benchmarking shows a speedup of 0.67% on a height 4 tree with 2048
entries.

Link: https://lore.kernel.org/20260821192627.4085470-10-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:30 -07:00
Liam R. Howlett (Oracle)
4bd59d5bc2 maple_tree: use prefetched value in mas_wr_store_type()
The slot contents exist in wr_mas->content, which has less overhead than
reading the slot again.

Link: https://lore.kernel.org/20260821192627.4085470-9-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:29 -07:00
Liam R. Howlett (Oracle)
7d1e343527 maple_tree: clarify comments on mas_nomem()
When an allocation completely fails, the return is false.  If the
allocation succeeds or partially succeeds, return true to indicate a retry
of the operation.  Note that since the lock may have been dropped, the
operation is retried from the start - including potentially allocating
more memory.

Link: https://lore.kernel.org/20260821192627.4085470-8-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:29 -07:00
Liam R. Howlett (Oracle)
acac9108a6 maple_tree: drop dead code from mas_extend_spanning_null()
mas_extend_spanning_null() had a clause if the end of the range being
written (mas->last) is the same as the end of the existing range it is
overwriting (wr_mas->r_max), action will be taken.

This code path is not possible because the only calling function
increments mas->last (unless it's ULONG_MAX) to walk to one beyond the
write and then resets the value back to the initial value.

In the case of mas->last == ULONG_MAX, then the second part of the
statement will always be false - mas->last cannot be less than the node
max.

This code never executed and is flawed anyways (the arguments are
incorrectly ordered), so removing it is the safest action.  Since the code
never executes, it is not fixing any issue so Fixes tag is not given.

Link: https://lore.kernel.org/20260821192627.4085470-6-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:28 -07:00
Liam R. Howlett (Oracle)
19e269917d maple_tree: add write lock checking with lockdep sequence numbers
Use the lockdep sequence numbers to ensure the write lock is not dropped
between write operations.  The lockdep sequence is recorded on any walk
that starts from the top of the tree and re-checked prior to any operation
using an active node.

When lockdep detects an issue, it sets debug_locks to 0 disabling further
reports.  __lock_sequnece() will return u32 ~0 when debug_locks is zero,
and the real sequnece count cannot return such a high value as it is less
than 32bits.

By always updating the sequence number, regardless of lock state and by
ignoring ~0 value in the sequence number will avoid ever printing a
WARN_ON when lockdep sets debug_locks to 0.

Link: https://lore.kernel.org/20260821192627.4085470-4-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Breno Leitao <leitao@debian.org>
Tested-by: Breno Leitao <leitao@debian.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:28 -07:00
Liam R. Howlett (Oracle)
9e32ec53b1 maple_tree: add rcu locking check when LOCKDEP is enabled
Patch series "maple_tree: lock checking and clean ups", v3.

In this series:
1. Try to detect lock issues
  A number of syzbot reports are incorrectly pointing to the mm exit as
  a source of the locking error.  The first three patches attempt to
  help users detect errors in their locking - but they still have to use
  LOCKDEP.  I guess it's still down to hope and prayers.

2. Documentation fixes
  The documentation was lacking clarity, there are updates to try and
  help the users, especially around the erase() cases.

3. Two benign issues
  The cyclic allocator may have a race, although no in-kernel user can
  hit it.
  The erase functions may cause allocation issues if used with the
  incorrect locking type, but none are present in-tree.

4. The erase gfp uses
  mas_erase() and mtree_erase() do not take a gfp argument.  To improve
  reliability of the erase, the first attempt to allocate will be
  GFP_NOWAIT, followed by a retry (if necessary of GFP_KERNEL |
  GFP_NOFAIL.  This will ensure the data is gone.  I've updated the
  documentation to make it more clear as well.  mas_store() is not
  addressed in the same way, but may need to be updated at a later date,
  but that may require changing callers so it is out of scope here.

Beyond these goals there are some test fixes, some general speed-up
patches targeting extra work and cycles, and dropping dead code.


This patch (of 19):

When CONFIG_LOCKDEP and CONFIG_RCU_STRICT_GRACE_PERIOD is enabled, check
for rcu locking issues by recording the grace period in the maple state
and checking the rcu window is still valid whenever the maple state is
reused with a state that is not MA_START or MA_PAUSED.

Link: https://lore.kernel.org/20260821192627.4085470-1-liam@infradead.org
Link: https://lore.kernel.org/20260821192627.4085470-2-liam@infradead.org
Signed-off-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Mason <clm@meta.com>
Cc: Chuck Lever <cel@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joe Perches <joe@perches.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:27 -07:00
Qiang Liu
0d0878fd7c lib/test_hmm: fix garbage pfn and wrong direction in devmem fault debug
Move pr_debug() inside the `if (dpage)` block to avoid printing garbage
pfn for NULL dpage, and correct the direction label from "sys to dev" to
"dev to sys".

Link: https://lore.kernel.org/20260812092856.55296-1-liuqiangneo@163.com
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Assisted-by: Qoder:Qwen-3.8-MAX-Preview
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:24 -07:00
Tejun Heo
f525001b33 percpu: drop CONFIG_DEBUG_FORCE_WEAK_PER_CPU
alpha requires percpu variables in modules to be defined as weak so that the
compiler generates GOT based external references for them. This puts two
extra restrictions on percpu variable definitions. The symbol must be
globally unique even when static and a static percpu variable can't be
defined inside a function. DEBUG_FORCE_WEAK_PER_CPU exists to give generic
code build coverage for these restrictions without building for alpha.

MEM_ALLOC_PROFILING defines a static percpu counter at each allocation call
site and thus can't be built with weak percpu definitions, so it depends on
!DEBUG_FORCE_WEAK_PER_CPU. As allmodconfig enables DEBUG_FORCE_WEAK_PER_CPU,
this knocks MEM_ALLOC_PROFILING out of allmodconfig build coverage.

allmodconfig coverage for MEM_ALLOC_PROFILING is worth more than build
coverage for restrictions which only matter to alpha module builds. Drop
DEBUG_FORCE_WEAK_PER_CPU. Restriction violations will now show up only on
alpha builds.

Link: https://lore.kernel.org/178656406317.2437052.7257990869957704195@slm.duckdns.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Gabriele Monaco <gmonaco@redhat.com>	[include/rv/da_monitor.h]
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:24 -07:00
Mark Sercombe
cdd719b3f2 maple_tree: fix comment typo
Fix a spelling mistake n a code comment.  This is a comment only change
with no functional impact.

Link: https://lore.kernel.org/20260813183847.474357-1-sercombe.joel.mark@gmail.com
Signed-off-by: Mark Sercombe <sercombe.joel.mark@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andrew Ballance <andrewjballance@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:19 -07:00
Suren Baghdasaryan
1d581ab234 alloc_tag: add ioctl to /proc/allocinfo
Patch series "alloc_tag: introduce IOCTL-based filtering for MAP", v8.

Currently, memory allocation profiling data is primarily exposed through
/proc/allocinfo.  While useful for manual inspection, this text-based
interface poses challenges for production monitoring and large-scale
analysis:

1. Userspace must parse large amounts of text to extract specific
fields.
2. To find specific tags, userspace must read the entire dataset,
requiring many context switches and high data copying.
3. The kernel currently aggregates per-CPU counters for every allocation
size, even those the user intends to filter out immediately.

This series introduces a new IOCTL-based binary interface for allocinfo
that supports kernel-side filtering.  By allowing the user to specify a
filter mask, we significantly reduce the work performed in-kernel and the
amount of data transferred to userspace.  The IOCTL mechanism was chosen
for allocinfo to address the per-CPU counter aggregation bottleneck.  A
traditional read() operation must report the total allocation count and
sizes for every code tag in the system.  Doing so requires iterating
across all CPUs to sum their per-CPU counters for thousands of tags, which
introduces substantial runtime overhead.

The IOCTL interface allows userspace to push selective filtering criteria
directly into the kernel before the per-CPU counter aggregation.  The
kernel aggregates per-CPU counters only for a small subset of tags that
match the filter.  This results in significant performance improvement.

Beyond fast filtered retrieval, the IOCTL foundation allows introducing a
context capture mechanism in the future to capture the context for
specific allocations.

Performance measurements were conducted on an Intel Xeon Platinum 8481C
(224 CPUs) with caches dropped before each run.

The IOCTL mechanism shows a ~20x performance improvement for
filtered queries. The kernel avoids the expensive per-CPU counter
aggregation (alloc_tag_read) for any tags that fail the initial string
or location filters.

Scenario 1: Specific File Filtering (arch/x86/events/rapl.c)
1. Traditional (cat /proc/allocinfo | grep): 22ms (sys)
2. IOCTL Interface: 1ms (sys)

Scenario 2: Compound Filtering (Filename + Size)
1. Traditional: (cat ... | grep | awk): 21ms (sys)
2. IOCTL Interface: 1ms (sys)

Scenario 3: Size-Based Filtering (min_size = 1MB)
1. Traditional: (cat ... | awk): 21ms (sys)
2. IOCTL Interface: 14ms (sys)


This patch (of 6):

Add the following ioctl commands for /proc/allocinfo file:

ALLOCINFO_IOC_CONTENT_ID - gets content identifier which can be used to
check whether the file content has changed specifically due to module
load/unload.  Every time a module is loaded / unloaded, the returned value
will be different.  By comparing the identifier value at the beginning and
at the end of the content retrieval operation, users can validate
retrieved information for consistency.

ALLOCINFO_IOC_GET_AT - gets the record at the specified position.  This is
the position of a record in /proc/allocinfo.

ALLOCINFO_IOC_GET_NEXT - gets the record next to the last retrieved one. 
If no records were previously retrieved, returns the first record.

Note, function file and module names often have the same prefixes,
therefore when filtering for them, we compare the last 64 characters to
minimize the chances of name collisions.

[akpm@linux-foundation.org: include compat.h, per Suren]
  Closes: https://lore.kernel.org/oe-kbuild-all/202607091820.qbjlGhKK-lkp@intel.com/
Link: https://lore.kernel.org/cover.1783532853.git.abhishekbapat@google.com
Link: https://lore.kernel.org/15596de2607ef13e7c77c6d74763f4ae992ec475.1783532853.git.abhishekbapat@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Abhishek Bapat <abhishekbapat@google.com>
Acked-by: Hao Ge <hao.ge@linux.dev>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Sourav Panda <souravpanda@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:12 -07:00
Zhan Xusheng
36a9799b2c maple_tree: remove unused mas_is_root_limits()
The last callers of mas_is_root_limits() were removed by commit
b8852ef30c ("maple_tree: remove maple big node and subtree structs"),
together with the maple subtree state (mast_*) code that used it.  As a
static inline it does not trigger -Wunused-function, so it went unnoticed.

Remove it. No functional change.

Link: https://lore.kernel.org/20260805070529.4118794-1-zhanxusheng@xiaomi.com
Signed-off-by: Zhan Xusheng <zhanxusheng@xiaomi.com>
Reviewed-by: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andrew Ballance <andrewjballance@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:43:08 -07:00
Zi Yan
789763523f xarray: honor XA_FLAGS_ACCOUNT in xas_split_alloc()
XArray operations that allocate xa_nodes, such as xas_nomem() and
xas_alloc(), add __GFP_ACCOUNT when the array has XA_FLAGS_ACCOUNT set. 
This charges the allocated memory and avoids the workingset convergence
issue described by commit 7b785645e8 ("mm: fix page cache convergence
regression").

xas_split_alloc() does not add _GFP_ACCOUNT when XA_FLAGS_ACCOUNT is
present.  Fix it.

Link: https://lore.kernel.org/20260804-add-gfp_account-to-xas_split_alloc-v3-2-38cb3ff325c5@nvidia.com
Fixes: 6b24ca4a1a ("mm: Use multi-index entries in the page cache")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-24 18:42:59 -07:00
Stanislav Kinsburskii
9365813cad selftests/mm: add HMM test for mmap lock-dropping faults
Add test_hmm coverage for the HMM lock-dropping fault path.  The test
module gets a new HMM_DMIRROR_READ_UNLOCKED ioctl that calls
hmm_range_fault_unlocked_timeout() with a timeout of 0, exercising the
unbounded retry mode while allowing the mmap lock to be dropped during
fault handling.

Add a userfaultfd_read selftest that registers an anonymous mapping with
UFFDIO_REGISTER_MODE_MISSING, services the faults from a handler thread
with UFFDIO_COPY, and verifies that HMM can read back the data supplied by
the handler.  This exercises the path where handle_mm_fault() drops
mmap_lock and hmm_range_fault_unlocked_timeout() restarts the walk
internally.

Assisted-by: GitHub-Copilot:claude-opus-4.6
Link: https://lore.kernel.org/20260723-hmm-v10-v11-3-c55b003a4b61@gmail.com
Signed-off-by: Stanislav Kinsburskii <skinsburskii@gmail.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lizhi Hou <lizhi.hou@amd.com>
Cc: Long Li <longli@microsoft.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Lyude <lyude@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Oded Gabbay <ogabbay@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Zimemrmann <tzimmermann@suse.de>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04 19:18:54 -07:00
Watson Wheeler
fe8c4d774d lib/maple_tree: add missing spaces after switch keyword
Add the required space before the opening parenthesis in switch statements
to conform to kernel coding style.

Link: https://lore.kernel.org/20260623061730.2024-1-git@tazy.dev
Signed-off-by: Watson Wheeler <git@tazy.dev>
Reviewed-by: Liam Howlett <liam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04 19:18:29 -07:00
Stanislav Kinsburskii
6a8024511d lib/test_hmm: fail dmirror_fault() when the mirrored mm is gone
dmirror_fault() is called from the dmirror_read() and dmirror_write()
retry loops after dmirror_do_read() or dmirror_do_write() finds a missing
device page table entry.

If the mirrored mm has already exited, mmget_not_zero() fails.  The
current code returns 0 in that case, which tells the caller that faulting
succeeded even though no page was faulted and no device page table entry
was installed.  The caller then retries the same address, hits -ENOENT
again, and can loop forever without making progress.

Return -EFAULT instead, so the ioctl fails when the mirrored mm is no
longer faultable.

Link: https://lore.kernel.org/178294308408.327222.3319445682023999403.stgit@skinsburskii
Fixes: b2ef9f5a5c ("mm/hmm/test: add selftest driver for HMM")
Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-30 19:40:31 -07:00
Lorenzo Stoakes
3c77682d80 mm: move alloc tag to mm
The alloc tagging work is really mm-specific, so move alloc_tag.c to mm/
and additionally update the MAINTAINERS entry to place it within memory
management and port over the Kconfig and Makefile code to mm.

Link: https://lore.kernel.org/20260625184857.2193482-3-surenb@google.com
Signed-off-by: Lorenzo Stoakes <ljs@kernel.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Tested-by: Hao Ge <hao.ge@linux.dev>
Acked-by: Hao Ge <hao.ge@linux.dev>
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-28 21:12:03 -07:00
Matthew Wilcox (Oracle)
b55cc244d0 percpu_ref: fix documentation of maximum value
Tejun changd percpu_ref to use long instead of int back in 2014 but missed
updating this bit of the documentation.  Also add the documentation to the
htmldocs.

Link: https://lore.kernel.org/20241211204017.184512-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-28 21:11:55 -07:00
Linus Torvalds
62cc902415 Merge tag 'mm-hotfixes-stable-2026-07-27-14-18' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
 "13 hotfixes. All are cc:stable. 11 are for MM. All are singletons -
  please see the changelogs for details"

* tag 'mm-hotfixes-stable-2026-07-27-14-18' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  fs/proc/task_mmu: fix PAGEMAP_SCAN written state for PMD holes
  mm/hugetlb: fix list corruption in allocate_file_region_entries()
  mm: mglru: fix stale batch updates after memcg reparenting
  selftest: fix headers in fclog.c
  ocfs2: fix boundary check in ocfs2_check_dir_entry() to use buffer offset
  mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()
  mm/util: don't read __page_2 for order-1 folios in snapshot_page()
  mm/hugetlb: fix swap entry corruption when clearing uffd-wp at fork()
  mm: migrate_device: fix pte_pfn/pte_dirty called on non-present PTE
  fs/proc/task_mmu: fix PAGEMAP_SCAN written state for unpopulated ptes
  userfaultfd: wait on source PMD during UFFDIO_MOVE
  lib: test_hmm: use device devt for coherent device range selection
  mm/vmstat: fold stranded per-cpu node stats when a node comes online
2026-07-27 14:36:26 -07:00
Linus Torvalds
aa6fc3defb Merge tag 'for-next-keys-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd
Pull keys fixes from Jarkko Sakkinen:

 - An unprivileged keyring whose keys collide through the
   description-chunk path can drive assoc_array node splitting
   into an out-of-bounds slot write. Fix it.

 - Fix the DCP trusted keys backend

* tag 'for-next-keys-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
  assoc_array: trim the final shortcut word using the current chunk end
  keys: make keyring key-chunk byte order agree with keyring_diff_objects()
  keys: fix out-of-bounds read in keyring_get_key_chunk()
  KEYS: trusted: dcp: fix key_len validation and calc_blob_len() return type
2026-07-27 14:14:11 -07:00
Linus Torvalds
86ba24c41a Merge tag 'slab-for-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:

 - Prevent unbounded recursion in free path with memory allocation
   profiling, which has caused a stack overflow on a Meta production
   host due to a 125-deep __free_slab<->kfree recursion (Harry Yoo)

 - Fix type-based partitioning confusing sparse which does not know
   __builtin_infer_alloc_token() (Marco Elver)

 - Fix a potential memory leak in bulk freeing path on NUMA machines
   (Shengming Hu)

* tag 'slab-for-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  slab: silence sparse warning with type-based partitioning
  mm/slab: prevent unbounded recursion in free path with new kmalloc type
  lib/alloc_tag: introduce mem_alloc_profiling_permanently_disabled()
  mm/slab: decouple SLAB_NO_SHEAVES from SLAB_NO_OBJ_EXT
  mm/slab: fix a memory leak due to bootstrapping sheaves twice
  mm/slub: fix lost local objects when bulk remote free batch fills
2026-07-24 07:28:35 -07:00
Michael Bommarito
a82c8a05e8 assoc_array: trim the final shortcut word using the current chunk end
assoc_array_walk() masks off the bits past shortcut->skip_to_level in the
word that contains skip_to_level, gated on
round_up(sc_level, ASSOC_ARRAY_KEY_CHUNK_SIZE) > skip_to_level.

That guard is wrong in two opposite ways:

 - When sc_level is word-aligned (every word after the first) round_up()
   is a no-op, so the guard is sc_level > skip_to_level and never fires for
   the word that holds skip_to_level.  A shortcut that spans more than one
   word and ends in the middle of its last word leaves that word untrimmed,
   and its stale high bits leak into the dissimilarity word and can steer
   the walk down the wrong descendant.

 - When sc_level is unaligned (the first word) and skip_to_level sits on
   the next chunk boundary, sc_level + CHUNK would exceed skip_to_level and
   fire the trim with shift = skip_to_level & CHUNK_MASK == 0, which clears
   the whole dissimilarity word and makes a differing shortcut compare
   equal.

Use the end of the chunk that contains sc_level instead:

	skip_to_level < round_down(sc_level, CHUNK) + CHUNK

For an aligned sc_level whose word holds skip_to_level this now fires (the
first bug); for an unaligned sc_level with skip_to_level on the following
boundary it does not, so shift is never 0 when the branch runs and the trim
never clears the whole word.

Fixes: 3cb989501c ("Add a generic associative array implementation.")
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lore.kernel.org/r/20260719161505.2423935-4-michael.bommarito@gmail.com
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2026-07-23 18:23:45 +03:00
Stanislav Kinsburskii
4fc0892353 lib: test_hmm: use device devt for coherent device range selection
Commit af69016dab ("lib: test_hmm: implement a device release method")
moved the initial dmirror_allocate_chunk() call before cdev_device_add(). 
That means the struct cdev has not been added yet, so cdev_add() has not
initialized mdevice->cdevice.dev.

The coherent-device range selection uses the device minor to choose
between spm_addr_dev0 and spm_addr_dev1.  Reading
MINOR(mdevice->cdevice.dev) before cdev_add() therefore always sees an
uninitialized dev_t.  As a result, both coherent devices select the same
physical range, and adding the second device fails due to the overlapping
dev_pagemap range.

Use mdevice->device.devt instead.  It is initialized in
dmirror_device_init() before dmirror_allocate_chunk() is called and is the
same dev_t later passed to cdev_device_add().

Link: https://lore.kernel.org/178277581197.172200.16265155329935822153.stgit@skinsburskii
Fixes: af69016dab ("lib: test_hmm: implement a device release method")
Signed-off-by: Stanislav Kinsburskii <skinsburskii@gmail.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Balbir Singh <balbirs@nvidia.com>
Cc: Zenghui Yu (Huawei) <zenghui.yu@linux.dev>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:26 -07:00
Linus Torvalds
abc69ae5d2 Merge tag 'v7.2-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:

 - Fix potential crash in rhashtable walk

* tag 'v7.2-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  rhashtable: clear stale iter->p on table restart
2026-07-20 12:55:50 -07:00
Linus Torvalds
0dde292a4c Merge tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull crypto library fixes from Eric Biggers:

 - Fix a build error in certain configurations

 - Clarify some parts of the documentation

 - Remove unused code that I forgot to remove in commit cf52058dcd
   ("lib/crypto: powerpc/md5: Drop powerpc optimized MD5 code")

* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
  crypto: aes - Fix conditions for selecting MAC dependencies
  lib/crypto: docs: Improve introduction sentence
  lib/crypto: docs: Fix some sentence fragments
  lib/crypto: md5: Remove support for md5_mod_init_arch()
2026-07-17 10:53:57 -07:00
Cen Zhang (Microsoft)
8173f7e2ce rhashtable: clear stale iter->p on table restart
rhashtable_walk_start_check() has two restart paths when resuming a walk.
When iter->walker.tbl is valid, it re-validates iter->p against the table
and sets iter->p = NULL if the object is gone.  When iter->walker.tbl is
NULL (table was freed during resize), it resets slot and skip but forgets
to clear iter->p.

rhashtable_walk_next() then dereferences the stale iter->p, reading
freed memory.  This is a use-after-free.

Any caller that does multi-fragment rhashtable walks across
walk_stop/walk_start boundaries is affected.  Concrete cases include
netlink_diag (__netlink_diag_dump in net/netlink/diag.c) and TIPC
(tipc_nl_sk_walk in net/tipc/socket.c).

Crash stack (netlink_diag):
  BUG: KASAN: slab-use-after-free in rhashtable_walk_next+0x365/0x3c0
  Read of size 8 at addr ffff88801a9d2438 (freed kmalloc-2k, offset 1080)
  Call Trace:
   rhashtable_walk_next+0x365/0x3c0 (lib/rhashtable.c:1016)
   __netlink_diag_dump+0x160/0x760 (net/netlink/diag.c:122)
   netlink_diag_dump+0xc2/0x240
   netlink_dump+0x5bc/0x1270
   netlink_recvmsg+0x7a3/0x980
   sock_recvmsg+0x1bc/0x200
   __sys_recvfrom+0x1d4/0x2c0

Fixes: 5d240a8936 ("rhashtable: improve rhashtable_walk stability when stop/start used.")
Cc: <stable@vger.kernel.org>
Reported-by: AutonomousCodeSecurity@microsoft.com
Reported-by: Yuan Tan <yuantan098@gmail.com>
Closes: https://lore.kernel.org/linux-crypto/CAB8m9Wh559e+=n8z51gB8DrbEyCc2mc0MgGjrRR6_VXBmU=2AQ@mail.gmail.com
Signed-off-by: Cen Zhang (Microsoft) <blbllhy@gmail.com>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2026-07-17 09:04:45 +10:00
Linus Torvalds
37e2f878a7 Merge tag 'linux_kselftest-kunit-fixes-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kunit fix from Shuah Khan:
 "Fix warning suppressions with kunit built as module:

  CONFIG_KUNIT is a tristate symbol but the warning suppression code in
  lib/bug.c is only built if it's built-in due to it using a plain
  #ifdef, rendering warning suppressions broken for kunit build as
  loadable module.

  kunit_is_suppressed_warning() already has a stub for when kunit is
  disabled so drop that guard entirely"

* tag 'linux_kselftest-kunit-fixes-7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  bug: fix warning suppressions with kunit built as module
2026-07-15 16:48:02 -07:00
Harry Yoo (Oracle)
a37b0066a1 lib/alloc_tag: introduce mem_alloc_profiling_permanently_disabled()
mem_alloc_profiling_enabled() tells whether memalloc profiling is
currently enabled. However, even when this function returns false,
it can be enabled later.

However, this is not enough. Some optimizations can be applied only when
memalloc profiling is permanently disabled. For example, to skip the
creation of KMALLOC_NO_OBJ_EXT caches at boot time, mem_profiling must
be set to "never", "0" w/ debugging on, or have been shutdown so that
it can no longer be enabled.

Introduce mem_alloc_profiling_permanently_disabled() for this purpose.

Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Link: https://patch.msgid.link/20260713-kmalloc-no-objext-v3-3-47c7bd138de7@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
2026-07-14 16:44:40 +02:00
Bartosz Golaszewski
5142c56651 bug: fix warning suppressions with kunit built as module
CONFIG_KUNIT is a tristate symbol but the warning suppression code in
lib/bug.c is only built if it's built-in due to it using a plain #ifdef,
rendering warning suppressions broken for kunit build as loadable module.

kunit_is_suppressed_warning() already has a stub for when kunit is
disabled so drop that guard entirely.

Link: https://lore.kernel.org/r/20260708095459.12111-1-bartosz.golaszewski@oss.qualcomm.com
Suggested-by: Albert Esteve <aesteve@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 85347718ab ("bug/kunit: Core support for suppressing warning backtraces")
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Albert Esteve <aesteve@redhat.com>
Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-07-10 10:26:58 -06:00
Eric Biggers
e073f1238e crypto: aes - Fix conditions for selecting MAC dependencies
Starting in commit 7137cbf2b5 ("crypto: aes - Add cmac, xcbc, and
cbcmac algorithms using library"), the aes module (CRYPTO_AES) supports
CBC based MACs using the corresponding library functions.

To avoid including unneeded functionality, that support honors the
existing CRYPTO_CMAC, CRYPTO_XCBC, and CRYPTO_CCM kconfig options.  The
dependencies are selected if at least one of those is enabled.

However, the select statements don't correctly handle the case where
CRYPTO_AES=y and (for example) CRYPTO_CMAC=m.  In that case the
dependencies get selected at level 'm', due to how the kconfig language
works.  That causes a linker error.

Fix this by changing the selection conditions to use '!= n'.

A similar issue also exists for CRYPTO_LIB_AES's conditional selection
of CRYPTO_LIB_UTILS.  The same '!= n' would work, but instead just make
CRYPTO_LIB_AES always select CRYPTO_LIB_UTILS.  CRYPTO_LIB_UTILS is
lightweight, and it's needed by most AES modes and many other things.

Fixes: 7137cbf2b5 ("crypto: aes - Add cmac, xcbc, and cbcmac algorithms using library")
Fixes: 309a7e514d ("lib/crypto: aes: Add support for CBC-based MACs")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260709022954.45113-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2026-07-09 11:06:22 -04:00
Huihui Huang
0a6070839b tracing: Prevent out-of-bounds read in glob matching
String event fields are not necessarily NUL-terminated, so the filter
predicate functions (filter_pred_string(), filter_pred_strloc() and
filter_pred_strrelloc()) pass the field length to the regex match
callbacks, and the length-aware matchers honour it.

regex_match_glob() was the exception: it ignored the length and called
glob_match(), which scans the string until it hits a NUL byte. Some
string fields are not NUL-terminated. One example is the dynamic char
array of the xfs_* namespace tracepoints, which is copied without a
trailing NUL. For such a field, glob matching reads past the end of
the event field, causing a KASAN slab-out-of-bounds read in
glob_match(), reached via regex_match_glob() and filter_match_preds()
from the xfs_lookup tracepoint.

Add a length-bounded glob_match_len() and use it from regex_match_glob()
so glob matching always stops at the field boundary. The matching loop
is factored into a shared helper so glob_match() keeps its behaviour.

Fixes: 60f1d5e3ba ("ftrace: Support full glob matching")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/da1aaf125fc3b63320b0c540fd6afa7c3d5b4f1a.1782836943.git.hhhuang@smu.edu.sg
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Zhengchuan Liang <zcliangcn@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Assisted-by: Codex:GPT-5.4
Signed-off-by: Huihui Huang <hhhuang@smu.edu.sg>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-07-07 10:42:28 -04:00
Eric Biggers
1002500f54 lib/crypto: md5: Remove support for md5_mod_init_arch()
No definitions of md5_mod_init_arch() remain, so remove the code that
handles it.

Link: https://patch.msgid.link/20260629032552.26100-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2026-07-05 12:48:50 -07:00
Linus Torvalds
590cae7152 Merge tag 'riscv-for-linus-7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Paul Walmsley:

 - Fix a crash when a kretprobe reads from the stack

 - Fix an issue with the build-time mcount sorter that broke ftrace

 - Fix the rv32 IRQ stack frame padding to match the ABI

 - Only defer IOMMU configuration during initialization. This avoids an
   issue where IOMMU configuration could be indefinitely deferred

 - Add the missing build salt to the vDSO

 - Now that RISC-V systems with higher numbers of cores are starting to
   become available, raise NR_CPUS for RISC-V to 256

 - Clean up some warnings from sparse caused by the RISC-V-optimized
   RAID6 code

 - Clean up our __cpu_up() code with a few minor fixes

* tag 'riscv-for-linus-7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: probes: save original sp in rethook trampoline
  riscv: Fix 32-bit call_on_irq_stack() frame pointer ABI
  scripts/sorttable: Handle RISC-V patchable ftrace entries
  riscv: smp: use secs_to_jiffies in __cpu_up
  ACPI: RIMT: Only defer the IOMMU configuration in init stage
  riscv: Add build salt to the vDSO
  raid6: fix raid6_recov_rvv symbol undeclared warning
  raid6: fix riscv symbol undeclared warnigns
  riscv: Raise default NR_CPUS for 64BIT to 256
2026-07-03 15:07:24 -10:00
Linus Torvalds
71dfdfb020 Merge tag 'vfs-7.2-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:

 - netfs:

    - fix the decision when to disallow write-streaming with fscache in
      use, handling of asynchronous cache object creation, a double fput
      in cachefiles, clearing S_KERNEL_FILE without the inode lock held,
      page extraction bugs in the iov_iter helpers (a potential
      underflow, a missing allocation failure check, a memory leak, and
      a folio offset miscalculation), writeback error and ENOMEM
      handling, DIO write retry for filesystems without a
      ->prepare_write() method, and the replacement of the wb_lock mutex
      with a bit lock plus writethrough collection offload so that
      multiple asynchronous writebacks don't interfere with each other.

    - Fix the barriering when walking the netfs subrequest list during
      retries as it was possible to see a subrequest that was just added
      by the application thread.

 - iomap:

    - Change iomap to submit read bios after each extent instead of
      building them up across extents. The old behavior was considered
      problematic for a while and now caused an actual erofs bug.

    - Guard the ioend io_size EOF trim in iomap against underflow when a
      concurrent truncate moves EOF below the start of the ioend,
      wrapping io_size to a huge value.

 - overlayfs

    - Fix a stale overlayfs comment about the locking order.

    - Store the linked-in upper dentry instead of the disconnected
      O_TMPFILE dentry during overlayfs tmpfile copy-up. With a FUSE or
      virtiofs upper layer ->d_revalidate() would try to look up "/" in
      the workdir and fail, causing persistent ESTALE errors that broke
      dpkg and apt.

 - vfs-bpf:

   Have the bpf_real_data_inode() kfunc take a struct file instead of a
   dentry so it is usable from the bprm_check_security, mmap_file, and
   file_mprotect hooks, and rename it from bpf_real_inode() to make the
   data-inode semantics explicit. The kfunc landed this cycle so the
   change is safe.

 - afs:

   NULL pointer dereferences in the callback service and in
   afs_get_tree(), several memory and refcount leaks, missing locking
   around the dynamic root inode numbers and premature cell exposure
   through /afs, a netns destruction hang caused by a misplaced
   increment of net->cells_outstanding, a bulk lookup malfunction caused
   by the dir_emit() API change, inode (re)initialisation issues, and
   assorted smaller fixes to error codes, seqlock handling, and debug
   output.

 - vfs:

   Refuse O_TMPFILE creation with an unmapped fsuid or fsgid and add a
   selftest for it.

 - vboxsf:

   Add Jori Koolstra as vboxsf maintainer, taking over from Hans de
   Goede.

 - dio:

   Release the pages attached to a short atomic dio bio; the REQ_ATOMIC
   size check error path leaked them.

 - procfs:

   Only bump the parent directory link count when registering
   directories in procfs. Registering regular files inflated the count
   and leaked a link on every create and remove cycle.

 - minix:

   Avoid an unsigned overflow in the minix bitmap block count
   calculation that let crafted images with huge inode or zone counts
   pass superblock validation and crash the kernel during mount.

 - cachefiles:

   Fix a double unlock in the cachefiles nomem_d_alloc error path left
   over from the start_creating() conversion.

 - fat:

   Stop fat from reading directory entries past the 0x00
   end-of-directory marker. If the trailing on-disk slots aren't
   zero-filled the driver surfaced arbitrary garbage as directory
   entries.

 - freexvfs:

   Don't BUG() on unknown typed-extent types in freevxfs, reachable via
   ioctl(FIBMAP) on a crafted image; fail with an I/O error instead.

 - orangefs:

   Keep the readdir entry size 64-bit in orangefs fill_from_part().
   Truncating it to __u32 bypassed the bounds check and led to
   out-of-bounds reads triggerable by the userspace client.

 - xfs:

   Fix the error unwind in xfs_open_devices() which released the rt
   device file twice and left dangling buftarg pointers behind that were
   freed again when the failed mount was torn down.

 - exec:

   Fix an off-by-one in the comment documenting the maximum binfmt
   rewrite depth in exec_binprm(). The code allows five rewrites, not
   four; restricting the code would break userspace so the comment is
   fixed instead.

 - file handles:

   Reject detached mounts in capable_wrt_mount(). A detached mount can
   be dissolved concurrently, leaving a NULL mount namespace that
   open_by_handle_at() would dereference.

* tag 'vfs-7.2-rc2.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (57 commits)
  netfs: Fix barriering when walking subrequest list
  iomap: submit read bio after each extent
  fuse: call fuse_send_readpages explicitly from fuse_readahead
  iomap: consolidate bio submission
  fhandle: reject detached mounts in capable_wrt_mount()
  netfs: Fix DIO write retry for filesystems without a ->prepare_write()
  netfs: Fix folio state after ENOMEM whilst under writeback iteration
  netfs: Fix writeback error handling
  netfs: Fix writethrough to use collection offload
  netfs: Replace wb_lock with a bit lock for asynchronicity
  netfs: Fix kdoc warning
  scatterlist: Fix offset in folio calc in extract_xarray_to_sg()
  iov_iter: Remove unused variable in kunit_iov_iter.c
  iov_iter: Fix a memory leak in iov_iter_extract_user_pages()
  iov_iter: Fix missing alloc fail check in iov_iter_extract_bvec_pages()
  iov_iter: Fix potential underflow in iov_iter_extract_xarray_pages()
  cachefiles: Fix file burial to take lock when unsetting S_KERNEL_FILE
  cachefiles: Fix double fput
  netfs: Fix netfs_create_write_req() to handle async cache object creation
  netfs: Fix decision whether to disallow write-streaming due to fscache use
  ...
2026-07-03 05:48:05 -10:00
David Howells
2bcd3ab372 scatterlist: Fix offset in folio calc in extract_xarray_to_sg()
Fix the calculation of the offset in the folio being extracted in
extract_xarray_to_sg().

Note that in the near future, ITER_XARRAY should be removed.

Fixes: f5f82cd187 ("Move netfs_extract_iter_to_sg() to lib/scatterlist.c")
Link: https://sashiko.dev/#/patchset/20260608145432.681865-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/20260625140640.3116900-10-dhowells@redhat.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: Christoph Hellwig <hch@infradead.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Mike Marshall <hubcap@omnibond.com>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01 15:26:29 +02:00
David Howells
0442e23a5f iov_iter: Remove unused variable in kunit_iov_iter.c
Remove the no longer used variable 'b' from iov_kunit_copy_to_bvec().  The
variable is initialised and incremented, but nothing now makes use of the
value.

Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/20260625140640.3116900-9-dhowells@redhat.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
cc: Ming Lei <ming.lei@redhat.com>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: Christoph Hellwig <hch@infradead.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01 15:26:29 +02:00
David Howells
72698020e1 iov_iter: Fix a memory leak in iov_iter_extract_user_pages()
There's a potential memory leak in callers of iov_iter_extract_user_pages()
whereby if a pages array is allocated in function, it isn't freed before
returning of an error or 0.

Now, it's not a leak per se in iov_iter_extract_user_pages() as, if an
array is allocated, it's returned through *pages, so it's incumbent on the
caller to free it.  However, not all callers do.

Fix this by freeing the table and clearing *pages before returning an error
or 0.  Note that iov_iter_extract_pages() and its subfunctions are allowed
to return 0 without returning an array (for instance if the iterator count
is 0).

Fixes: 7d58fe7310 ("iov_iter: Add a function to extract a page list from an iterator")
Closes: https://sashiko.dev/#/patchset/20260616100821.2062304-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/20260625140640.3116900-8-dhowells@redhat.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: Christoph Hellwig <hch@infradead.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01 15:26:29 +02:00
David Howells
70531f4f3a iov_iter: Fix missing alloc fail check in iov_iter_extract_bvec_pages()
Fix iov_iter_extract_bvec_pages() to check if want_pages_array() fails and,
if so, return -ENOMEM appropriately.

Fixes: e4e535bff2 ("iov_iter: don't require contiguous pages in iov_iter_extract_bvec_pages")
Link: https://sashiko.dev/#/patchset/20260608145432.681865-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/20260625140640.3116900-7-dhowells@redhat.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
cc: Ming Lei <ming.lei@redhat.com>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: Christoph Hellwig <hch@infradead.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01 15:26:28 +02:00
David Howells
55f4bb9373 iov_iter: Fix potential underflow in iov_iter_extract_xarray_pages()
In iov_iter_extract_xarray_pages(), if no pages are extracted because
there's a hole (or something otherwise unextractable) in the xarray, then
the calculation of maxsize at the end can go wrong if the starting offset
is not zero.

Fix this by returning 0 in such a case and freeing the page array if
allocated here rather than being passed in.

Note that in the near future, ITER_XARRAY should be removed.

Fixes: 7d58fe7310 ("iov_iter: Add a function to extract a page list from an iterator")
Link: https://sashiko.dev/#/patchset/20260608145432.681865-1-dhowells%40redhat.com
Link: https://sashiko.dev/#/patchset/20260616100821.2062304-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://patch.msgid.link/20260625140640.3116900-6-dhowells@redhat.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: Christoph Hellwig <hch@infradead.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Mike Marshall <hubcap@omnibond.com>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-07-01 15:26:28 +02:00
Breno Leitao
dec4d8118c bootconfig: fix NULL-pointer arithmetic in xbc_snprint_cmdline()
xbc_snprint_cmdline() is meant to be called twice: first with
buf=NULL, size=0 to probe the rendered length, then with a real
buffer to fill it (the standard snprintf() two-pass pattern). The
probe call makes the function compute "buf + size" (NULL + 0) and,
on every iteration, advance "buf += ret" from that NULL base and
pass the result back into snprintf().

Pointer arithmetic on a NULL pointer is undefined behavior. It is
harmless in the in-kernel callers today, but the follow-up patches
run this same code in the userspace tools/bootconfig parser at kernel
build time, where host UBSan / FORTIFY_SOURCE abort the build.

Track a running written length (size_t) instead of mutating @buf, and
only form "buf + len" when @buf is non-NULL. snprintf(NULL, 0, ...)
is itself well defined and returns the would-be length, so the
two-pass "probe then fill" usage returns identical byte counts.

Link: https://lore.kernel.org/all/20260626-bootconfig_using_tools-v7-1-24ab72139c29@debian.org/

Fixes: 51887d03ac ("bootconfig: init: Allow admin to use bootconfig for kernel command line")
Cc: stable@vger.kernel.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-01 08:08:27 +09:00
Ben Dooks
5c5dea43f6 raid6: fix raid6_recov_rvv symbol undeclared warning
The riscv recov_rvv.c should have included pq_arch.h for
the definition of raid6_recov_rvv. Add the include to
fix the following sparse warning:

lib/raid/raid6/riscv/recov_rvv.c:218:32: warning: symbol 'raid6_recov_rvv' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/20260622135535.481534-1-ben.dooks@codethink.co.uk
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-06-25 11:51:32 -06:00
Ben Dooks
625ee71c32 raid6: fix riscv symbol undeclared warnigns
The riscv rvv.c file is missing the include of pq_arch.h
which defines all the exported functions. Include this
to remove the following sparse warnings:

lib/raid/raid6/riscv/rvv.c:1225:1: warning: symbol 'raid6_rvvx1' was not declared. Should it be static?
lib/raid/raid6/riscv/rvv.c:1226:1: warning: symbol 'raid6_rvvx2' was not declared. Should it be static?
lib/raid/raid6/riscv/rvv.c:1227:1: warning: symbol 'raid6_rvvx4' was not declared. Should it be static?
lib/raid/raid6/riscv/rvv.c:1228:1: warning: symbol 'raid6_rvvx8' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Link: https://patch.msgid.link/20260622135207.480540-1-ben.dooks@codethink.co.uk
Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-06-25 11:47:39 -06:00
Linus Torvalds
90ae888a37 Merge tag 'core-urgent-2026-06-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc core fixes from Ingo Molnar:

 - Fix an MM-CID race that can cause an OOB write (Rik van Riel)

 - Fix a debugobjects OOM handling race (Thomas Gleixner)

* tag 'core-urgent-2026-06-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  debugobjects: Plug race against a concurrent OOM disable
  sched/mmcid: Fix OOB clear_bit when CID is MM_CID_UNSET in fixup path
2026-06-23 16:05:54 -07:00
Linus Torvalds
a1a8bab741 Merge tag 'mm-stable-2026-06-23-08-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:

 - "khugepaged: add mTHP collapse support" (Nico Pache)

   Provide khugepaged with the capability to collapse anonymous memory
   regions to mTHPs

 - "Remove CONFIG_READ_ONLY_THP_FOR_FS and enable file THP for writable
   files" (Zi Yan)

   Remove the READ_ONLY_THP_FOR_FS check in file_thp_enabled(), so that
   khugepaged and MADV_COLLAPSE can run on filesystems with PMD THP
   pagecache support even without READ_ONLY_THP_FOR_FS enabled

 - "make MM selftests more CI friendly" (Mike Rapoport)

   General fixes and cleanups to the MM selftests. Also move more MM
   selftests under the kselftest framework, making them more amenable to
   ongoing CI testing

 - "selftests/mm: fix failures and robustness improvements" and
   "selftests/mm: assorted fixes for hmm-tests" (Sayali Patil)

   Fix several issues in MM selftests which were revealed by powerpc 64k
   pagesize

* tag 'mm-stable-2026-06-23-08-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (118 commits)
  Revert "mm: limit filemap_fault readahead to VMA boundaries"
  mm/vmscan: pass NULL to trace vmscan node reclaim
  mm: use mapping_mapped to simplify the code
  selftests/mm: fix exclusive_cow test fork() handling
  selftests/mm: remove hardcoded THP sizing assumptions in hmm tests
  selftests/mm: allow PUD-level entries in compound testcase of hmm tests
  mm/gup_test: reject wrapped user ranges
  mm/page_frag: reject invalid CPUs in page_frag_test
  mm/damon/core: always put unsuccessfully committed target pids
  mm: page_isolation: avoid unsafe folio reads while scanning compound pages
  mm/shrinker: do not hold RCU lock in shrinker_debugfs_count_show()
  selftests: mm: fix and speedup "droppable" test
  mm: merge writeout into pageout
  MAINTAINERS: add Hao Ge as reviewer for codetag and alloc_tag
  selftests/mm: clarify alternate unmapping in compaction_test
  selftests/mm: move hwpoison setup into run_test() and silence modprobe output for memory-failure category
  selftests/mm: skip uffd-stress test when nr_pages_per_cpu is zero
  selftests/mm: skip uffd-wp-mremap if UFFD write-protect is unsupported
  selftests/mm: ensure destination is hugetlb-backed in hugetlb-mremap
  selftest/mm: register existing mapping with userfaultfd in hugetlb-mremap
  ...
2026-06-23 12:03:44 -07:00
Thomas Gleixner
b81dde13cc debugobjects: Plug race against a concurrent OOM disable
syzbot reported a puzzling splat:

   WARNING: kernel/time/hrtimer.c:443 at stub_timer+0xa/0x20

stub_timer() is installed as timer callback function in
hrtimer_fixup_assert_init(), which is invoked when
debug_object_assert_init() can't find a shadow object. In that case debug
objects emits a warning about it before invoking the fixup.

Though the provided console log lacks this warning and instead has the
following a few seconds before the splat:

     ODEBUG: Out of memory. ODEBUG disabled

So the object was looked up in debug_object_assert_init() and the lookup
failed due a concurrent out of memory situation which disabled debug
objects and freed the shadow objects:

debug_object_assert_init()
        if (!debug_objects_enabled)
        	return;                         obj = alloc();
                				if (!obj) {
							// Out of memory
                                                	debug_objects_enabled = false;
                                                        free_objects();
        obj = lookup_or_alloc();

        // The lookup failed because the other side
        // removed the objects, so this returns
        // an error code as the object in question
        // is not statically initialized

	if (!IS_ERR_OR_NULL(obj))
        	return;
        if (!obj) {
        	debug_oom();
                return;
        }

        print(...)
           if (!debug_objects_enabled)
                return;

        fixup(...)

The debug object splat is skipped because debug_objects_enabled is false,
but the fixup callback is invoked unconditionally, which makes the timer
disfunctional.

This is only a problem in debug_object_assert_init() and
debug_object_activate() as both have to handle statically initialized
objects and therefore must handle the error pointer return case
gracefully. All other places only handle the found/not found case and the
NULL pointer return is a signal for OOM. Otherwise they get a valid shadow
object.

Plug the hole by checking whether debug objects are still enabled before
invoking the print and fixup function in those two places.

Fixes: b84d435cc2 ("debugobjects: Extend to assert that an object is initialized")
Reported-by: syzbot+5e8dda76ca21dae314b6@syzkaller.appspotmail.com
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/874iiwlzlb.ffs@fw13
2026-06-22 16:38:57 +02:00