Patch series "introduce VM_MAYBE_GUARD and make it sticky", v4.
Currently, guard regions are not visible to users except through
/proc/$pid/pagemap, with no explicit visibility at the VMA level.
This makes the feature less useful, as it isn't entirely apparent which
VMAs may have these entries present, especially when performing actions
which walk through memory regions such as those performed by CRIU.
This series addresses this issue by introducing the VM_MAYBE_GUARD flag
which fulfils this role, updating the smaps logic to display an entry for
these.
The semantics of this flag are that a guard region MAY be present if set
(we cannot be sure, as we can't efficiently track whether an
MADV_GUARD_REMOVE finally removes all the guard regions in a VMA) - but if
not set the VMA definitely does NOT have any guard regions present.
It's problematic to establish this flag without further action, because
that means that VMAs with guard regions in them become non-mergeable with
adjacent VMAs for no especially good reason.
To work around this, this series also introduces the concept of 'sticky'
VMA flags - that is flags which:
a. if set in one VMA and not in another still permit those VMAs to be
merged (if otherwise compatible).
b. When they are merged, the resultant VMA must have the flag set.
The VMA logic is updated to propagate these flags correctly.
Additionally, VM_MAYBE_GUARD being an explicit VMA flag allows us to solve
an issue with file-backed guard regions - previously these established an
anon_vma object for file-backed mappings solely to have vma_needs_copy()
correctly propagate guard region mappings to child processes.
We introduce a new flag alias VM_COPY_ON_FORK (which currently only
specifies VM_MAYBE_GUARD) and update vma_needs_copy() to check explicitly
for this flag and to copy page tables if it is present, which resolves
this issue.
Additionally, we add the ability for allow-listed VMA flags to be
atomically writable with only mmap/VMA read locks held.
The only flag we allow so far is VM_MAYBE_GUARD, which we carefully ensure
does not cause any races by being allowed to do so.
This allows us to maintain guard region installation as a read-locked
operation and not endure the overhead of obtaining a write lock here.
Finally we introduce extensive VMA userland tests to assert that the
sticky VMA logic behaves correctly as well as guard region self tests to
assert that smaps visibility is correctly implemented.
This patch (of 9):
Currently, if a user needs to determine if guard regions are present in a
range, they have to scan all VMAs (or have knowledge of which ones might
have guard regions).
Since commit 8e2f2aeb8b ("fs/proc/task_mmu: add guard region bit to
pagemap") and the related commit a516403787 ("fs/proc: extend the
PAGEMAP_SCAN ioctl to report guard regions"), users can use either
/proc/$pid/pagemap or the PAGEMAP_SCAN functionality to perform this
operation at a virtual address level.
This is not ideal, and it gives no visibility at a /proc/$pid/smaps level
that guard regions exist in ranges.
This patch remedies the situation by establishing a new VMA flag,
VM_MAYBE_GUARD, to indicate that a VMA may contain guard regions (it is
uncertain because we cannot reasonably determine whether a
MADV_GUARD_REMOVE call has removed all of the guard regions in a VMA, and
additionally VMAs may change across merge/split).
We utilise 0x800 for this flag which makes it available to 32-bit
architectures also, a flag that was previously used by VM_DENYWRITE, which
was removed in commit 8d0920bde5 ("mm: remove VM_DENYWRITE") and hasn't
bee reused yet.
We also update the smaps logic and documentation to identify these VMAs.
Another major use of this functionality is that we can use it to identify
that we ought to copy page tables on fork.
We do not actually implement usage of this flag in mm/madvise.c yet as we
need to allow some VMA flags to be applied atomically under mmap/VMA read
lock in order to avoid the need to acquire a write lock for this purpose.
Link: https://lkml.kernel.org/r/cover.1763460113.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/cf8ef821eba29b6c5b5e138fffe95d6dcabdedb9.1763460113.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Following the extraction of sysfs code, this patch moves the sysctl
interface implementation into a dedicated file to further improve code
organization and maintainability of the hugetlb subsystem.
The following components are moved to mm/hugetlb_sysctl.c:
- proc_hugetlb_doulongvec_minmax()
- hugetlb_sysctl_handler_common()
- hugetlb_sysctl_handler()
- hugetlb_mempolicy_sysctl_handler() (CONFIG_NUMA)
- hugetlb_overcommit_handler()
- hugetlb_table[] sysctl table definition
- hugetlb_sysctl_init()
The hugetlb_internal.h header file is updated to declare the sysctl
initialization function with proper #ifdef guards for configurations
without CONFIG_SYSCTL support.
The Makefile is updated to compile hugetlb_sysctl.o when CONFIG_HUGETLBFS
is enabled. This refactoring reduces the size of hugetlb.c and logically
separates the sysctl interface from core hugetlb management code.
MAINTAINERS is updated to add new file hugetlb_sysctl.c.
No functional changes are introduced; all code is moved as-is from
hugetlb.c with consistent formatting.
Link: https://lkml.kernel.org/r/5bbee7ab5be71d0bb1aebec38642d7e83526bb7a.1762398359.git.zhuhui@kylinos.cn
Signed-off-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Hui Zhu <zhuhui@kylinos.cn>
Cc: David Hildenbrand <david@redhat.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/hugetlb: refactor sysfs/sysctl interfaces", v5.
hugetlb.c has grown significantly and become difficult to maintain. This
patch series extracts the sysfs and sysctl interface code into separate
dedicated files to improve code organization.
The refactoring includes:
- Patch 1: Extract sysfs interface into mm/hugetlb_sysfs.c
- Patch 2: Extract sysctl interface into mm/hugetlb_sysctl.c
No functional changes are introduced in this series. The code is moved
as-is, with only minor formatting adjustments for code style consistency.
This should make future maintenance and enhancements to the hugetlb
subsystem easier.
Testing: The patch series has been compile-tested and maintains the same
functionality as the original code.
This patch (of 2):
Currently, hugetlb.c contains both core management logic and sysfs
interface implementations, making it difficult to maintain. This patch
extracts the sysfs-related code into a dedicated file to improve code
organization.
The following components are moved to mm/hugetlb_sysfs.c:
- sysfs attribute definitions and handlers
- sysfs kobject management functions
- NUMA per-node hstate attribute registration
Several inline helper functions and macros are moved to
mm/hugetlb_internal.h:
- hstate_is_gigantic_no_runtime()
- next_node_allowed()
- get_valid_node_allowed()
- hstate_next_node_to_alloc()
- hstate_next_node_to_free()
- for_each_node_mask_to_alloc/to_free macros
To support code sharing, these functions are changed from static to
exported symbols:
- remove_hugetlb_folio()
- add_hugetlb_folio()
- init_new_hugetlb_folio()
- prep_and_add_allocated_folios()
- demote_pool_huge_page()
- __nr_hugepages_store_common()
The Makefile is updated to compile hugetlb_sysfs.o when CONFIG_HUGETLBFS
is enabled. This maintains all existing functionality while improving
maintainability by separating concerns.
MAINTAINERS is updated to add new file hugetlb_sysfs.c.
Link: https://lkml.kernel.org/r/cover.1762398359.git.zhuhui@kylinos.cn
Link: https://lkml.kernel.org/r/656a03dff7e2bb20e24e841ede81fdca01d21410.1762398359.git.zhuhui@kylinos.cn
Signed-off-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Hui Zhu <zhuhui@kylinos.cn>
Cc: David Hildenbrand <david@redhat.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
These arguments aren't modified by the function; mark them as const to
help the compiler.
Link: https://lkml.kernel.org/r/20251106203526.2368275-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Extract the zone number directly from the page instead of using the page's
zone number to look up the zone and asking the zone what its number is.
Link: https://lkml.kernel.org/r/20251106201452.2292631-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Extract the zone number directly from the folio instead of using the
folio's zone number to look up the zone and asking the zone what its
number is.
[ziy@nvidia.com: fix folio_zonenum() return type]
Link: https://lkml.kernel.org/r/26E8FF35-503E-4F14-98F7-7B4FA25FBD37@nvidia.com
Link: https://lkml.kernel.org/r/20251106201452.2292631-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Ying Huang <ying.huang@linux.alibaba.com>
Cc: Alistair Popple <apopple@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Extract the zone number directly from the folio instead of using the
folio's zone number to look up the zone and asking the zone what its
number is.
Also we should use &folio->page instead of casting from folio to page
Link: https://lkml.kernel.org/r/20251106201452.2292631-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The %pe format specifier is designed to print error pointers. It prints a
symbolic error name (eg. -EINVAL) and it makes the code simpler by
omitting PTR_ERR();
This patch fixes this cocci report:
lib/alloc_tag.c:776:63-70: WARNING: Consider using %pe to print PTR_ERR()
Link: https://lkml.kernel.org/r/20251105023925.1447482-1-zeng_chi911@163.com
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since we no longer attempt to write back filesystem folios in pageout()
(they will be filtered out by the following check in pageout()), and only
tmpfs/shmem folios and anonymous swapcache folios can be written back, we
can remove the redundant folio_test_private() when checking the folio's
refcount, as tmpfs/shmem and swapcache folios do not use the PG_private
flag.
While we're at it, we can open-code the folio refcount check instead of
adding a simple helper that has only one user.
Link: https://lkml.kernel.org/r/4cbbec5bb92397aa4597105f1f499aabf7a1901c.1758166683.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "some cleanups for pageout()", v2.
Since we no longer attempt to write back filesystem folios in pageout(),
and only tmpfs/shmem folios and anonymous swapcache folios can be written
back, we can remove the redundant folio_test_private() related logic to
simplify the logic of pageout(), as tmpfs/shmem and swapcache folios do
not use the PG_private flag.
This patch (of 2):
The folio_test_private() check in pageout() was introduced by commit
ce91b575332b ("orphaned pagecache memleak fix") in 2005 (checked from a
history tree[1]). As the commit message mentioned, it was to address the
issue where reiserfs pagecache may be truncated while still pinned. To
further explain, the truncation removes the page->mapping, but the page is
still listed in the VM queues because it still has buffers.
In 2008, commit a2b345642f ("Fix dirty page accounting leak with ext3
data=journal") seems to be dealing with a similar issue, where the page
becomes dirty after truncation, and it provides a very useful call stack:
truncate_complete_page()
cancel_dirty_page() // PG_dirty cleared, decr. dirty pages
do_invalidatepage()
ext3_invalidatepage()
journal_invalidatepage()
journal_unmap_buffer()
__dispose_buffer()
__journal_unfile_buffer()
__journal_temp_unlink_buffer()
mark_buffer_dirty(); // PG_dirty set, incr. dirty pages
In this commit a2b345642f, we forcefully clear the page's dirty flag
during truncation (in truncate_complete_page()).
Now it seems this was just a peculiar usage specific to reiserfs. Maybe
reiserfs had some extra refcount on these pages, which caused them to pass
the is_page_cache_freeable() check.
With the fix provided by commit a2b345642f and reiserfs being removed
in 2024 by commit fb6f20ecb1 ("reiserfs: The last commit"), such a case
is unlikely to occur again. So let's remove the redundant
folio_test_private() checks and related buffer_head release logic, and
just leave a warning here to catch such a bug.
[akpm@linux-foundation.org: redo comment, per David]
Link: https://lkml.kernel.org/r/17d1b293-e393-4989-a357-7eea74b3c805@redhat.com
[baolin.wang@linux.alibaba.com: remove comment and WARNing, per Hugh and others]
Link: https://lkml.kernel.org/r/392a9ca3-31ac-4447-bd44-3c656d63e4ca@linux.alibaba.com
Link: https://lkml.kernel.org/r/cover.1758166683.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/9ef0e560dc83650bc538eb5dcd1594e112c1369f.1758166683.git.baolin.wang@linux.alibaba.com
Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git [1]
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The avdcache is meant to be per-task; move it to a new
task_security_struct that is duplicated per-task.
Cc: stable@vger.kernel.org
Fixes: 5d7ddc59b3 ("selinux: reduce path walk overhead")
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
[PM: line length fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Before Linux had cred structures, the SELinux task_security_struct was
per-task and although the structure was switched to being per-cred
long ago, the name was never updated. This change renames it to
cred_security_struct to avoid confusion and pave the way for the
introduction of an actual per-task security structure for SELinux. No
functional change.
Cc: stable@vger.kernel.org
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Replace the direct calls to ksys_sync_helper() with the new
pm_sleep_fs_sync() in suspend and hibernation code paths.
This enables the new mechanism allowing the filesystem sync phase
to be interrupted.
Suggested-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Samuel Wu <wusamuel@google.com>
Co-developed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[ rjw: Subject and changelog edits, tags adjustment ]
Link: https://patch.msgid.link/20251119171426.4086783-3-wusamuel@google.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add helper function pm_sleep_fs_sync() and related data structures
as a preparation for allowing system suspend and hibernation to be
aborted by wakeup events while syncing file systems.
The new function, to be called by the suspend process in order to
sync file systems, uses a dedicated ordered workqueue to run
ksys_sync_helper() in parallel with the calling process. Next, it
waits for the completion of the filesystem sync and periodically
checks if any system wakeup events are pending, in which case it will
return an error.
If that happens while the filesystem sync is still in progress, it
will continue, possibly after pm_sleep_fs_sync() has returned, and if
that function is called again before the sync is complete, a new work
item to run ksys_sync_helper() again will be queued (and waited for)
to increase the likelihood of writing all of the dirty pages in memory
back to persistent storage.
Suggested-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Samuel Wu <wusamuel@google.com>
Co-developed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
[ rjw: Subject and changelog rewrite, tags adjustment ]
Link: https://patch.msgid.link/20251119171426.4086783-2-wusamuel@google.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since commit 9254c8ae9b ("nfsd: disallow file locking and delegations
for NFSv4 reexport"), file locking when reexporting an NFS mount via
NFSv4 is expressly prohibited by nfsd. Do the same in lockd:
Add a new nlmsvc_file_cannot_lock() helper that will test whether file
locking is allowed for a given file, and return nlm_lck_denied_nolocks
if it isn't.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Add a minimal entry for the block layout driver to make sure Christoph
who wrote the code gets Cced on all patches. The actual maintenance
stays with the nfsd maintainer team.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
set_tsk_need_resched(current) requires set_preempt_need_resched(current) to
work correctly outside of the scheduler.
Provide set_need_resched_current() which wraps this correctly and replace
all the open coded instances.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251116174750.665769842@linutronix.de
Merge sections for Asus Tinker Board and Asus Tinker Board S.
Asus Tinker Board S (Storage) is just a variant of Tinker Board
with an added eMMC chip.
Signed-off-by: Michael Opdenacker <michael.opdenacker@rootcommit.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://patch.msgid.link/20251119-merge-tinker-bindings-v1-1-4072b55750c1@rootcommit.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Replace udelay() with usleep_range() in check_freqs() to allow
CPU scheduling during frequency polling.
Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
[ rjw: Changelog edits ]
Link: https://patch.msgid.link/20251119031109.134583-1-kaushlendra.kumar@intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add documentation for longer term classification of workload type for
power or performance.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/20251118223620.554798-1-srinivas.pandruvada@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The affinity to set to the rescuers should be consistent in all paths
when a rescuer is in detached state. The affinity could be either
wq_unbound_cpumask or unbound_effective_cpumask(wq).
Related paths:
rescuer's worker_detach_from_pool()
update wq_unbound_cpumask
update wq's cpumask
init_rescuer()
Both affinities are Ok as long as they are consistent in all paths.
In the commit 449b31ad29 ("workqueue: Init rescuer's affinities as
the wq's effective cpumask") makes init_rescuer use
unbound_effective_cpumask(wq) which is consistent with then
apply_wqattrs_commit().
But using unbound_effective_cpumask(wq) requres much more code to
maintain the consistency, and it doesn't make much sense since the
affinity is only effective when the rescuer is not processing works.
wq_unbound_cpumask is more favorable.
So apply_wqattrs_commit() and the path of "updating wq's cpumask" had
been changed to not update the rescuer's affinity, and both the paths
of "updating wq_unbound_cpumask" and "rescuer's
worker_detach_from_pool()" had been changed to use wq_unbound_cpumask.
Now, make init_rescuer() use wq_unbound_cpumask for rescuer's affinity
and make all the paths consistent.
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When workqueue cpumask changes are committed, the DISASSOCIATED workers
affinity is not touched and this might be a problem down the line for
isolated setups when the DISASSOCIATED pools still have works to run
after the cpu is offline.
Make sure the workers' affinity is updated every time a workqueue cpumask
changes, so these workers can't break isolation.
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When a rescuer is attached to a pool, its affinity should be only
managed by the pool.
But updating the detached rescuer's affinity is still meaningful so
that it will not disrupt isolated CPUs when it is to be waken up.
But the commit d64f2fa064 ("kernel/workqueue: Let rescuers follow
unbound wq cpumask changes") updates the affinity unconditionally, and
causes some issues
1) it also changes the affinity when the rescuer is already attached to
a pool, which violates the affinity management.
2) the said commit tries to update the affinity of the rescuers, but it
misses the rescuers of the PERCPU workqueues, and isolated CPUs can
be possibly disrupted by these rescuers when they are summoned.
3) The affinity to set to the rescuers should be consistent in all paths
when a rescuer is in detached state. The affinity could be either
wq_unbound_cpumask or unbound_effective_cpumask(wq). Related paths:
rescuer's worker_detach_from_pool()
update wq_unbound_cpumask
update wq's cpumask
init_rescuer()
Both affinities are Ok as long as they are consistent in all paths.
But using unbound_effective_cpumask(wq) requres much more code to
maintain the consistency, and it doesn't make much sense since the
affinity is only effective when the rescuer is not processing works.
wq_unbound_cpumask is more favorable.
Fix the 1) issue by testing rescuer->pool before updating with
wq_pool_attach_mutex held.
Fix the 2) issue by moving the rescuer's affinity updating code to
the place updating wq_unbound_cpumask and make it also update for
PERCPU workqueues.
Partially cleanup the 3) consistency issue by using wq_unbound_cpumask.
So that the path of "updating wq's cpumask" doesn't need to maintain it.
and both the paths of "updating wq_unbound_cpumask" and "rescuer's
worker_detach_from_pool()" use wq_unbound_cpumask.
Cleanup for init_rescuer()'s consistency for affinity can be done in
future.
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The buf_nr_pages field in io_buffer_list was previously used to
determine whether the buffer list uses ring-provided buffers or classic
provided buffers. This is now determined by checking the IOBL_BUF_RING
flag.
Remove the buf_nr_pages field and update related comments.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The misc.h header is not included by the EFI stub, which is the only
C caller of sev_enable(). This means the fallback for cases where
CONFIG_AMD_MEM_ENCRYPT is not set is never used, so it can be dropped.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://patch.msgid.link/20250909080631.2867579-6-ardb+git@google.com
Add clock and reset ID defines for rv1126b.
Also add documentation for the rv1126b CRU core.
Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20251111025738.869847-3-zhangqing@rock-chips.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
The current path will have an independent PLL(LPLL\BPLL)
exclusively for the CPU to use.
As follows:
|-\
--lpll--| \
|mux|--[gate]--[div]--clk_core--
--gpll--| /
|-/
The new chip does not have a dedicated PLL for the cpu;
it is distributed nearby from the common PLL.
If there are special frequency requirements that require the
use of pvtpll, explanations will be submitted later.
The clock path of new soc CPU simplified as follows:
--gpll--|--\
| \
| \
| \
--v0pll--| mux |--[gate]--[div]--clk_core--
| /
| /
--v1pll--| /
|--/
Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Link: https://patch.msgid.link/20251111025738.869847-2-zhangqing@rock-chips.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
The TS233 is a 2 bay NAS similar to the TS433. Architecture-wise it really
seems to be the same minus the additional PCIe connected components the
TS433 has.
So it just uses two of the SoCs SATA ports and the SoC's gigabit ethernet.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20251112214206.423244-6-heiko@sntech.de
QNAP builds a number of variants of the RK3568-based NAS design.
Add the 2-bay TS233 variant.
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20251112214206.423244-5-heiko@sntech.de
The NAS series based around the rk3568 contains a number of models with
1-4 drives, that reuse most of the board structure.
Therefore move the shared parts to a dtsi, to be included by the devices.
As the smallest device is the 1-bay TS133, keep everything > slot1 in
the individual devicetree.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20251112214206.423244-4-heiko@sntech.de
The MCU's eeprom contains the unit's serial and a number of slots for
mac-addresses. As the MCU seems to be used in different devices, up to
8 mac addresses can live there and the unused slots are actually
initialized with empty mac-address strings like 00:00:00:00:05:09 .
Interestingly on the TS-433, the PCIe ethernet adapter brings its own
memory to hold its mac, and the gmac0 is supposed to get its mac from
the second mac-slot, while the first one stays empty.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patch.msgid.link/20251112214206.423244-3-heiko@sntech.de
The timer migration mechanism allows active CPUs to pull timers from
idle ones to improve the overall idle time. This is however undesired
when CPU intensive workloads run on isolated cores, as the algorithm
would move the timers from housekeeping to isolated cores, negatively
affecting the isolation.
Exclude isolated cores from the timer migration algorithm, extend the
concept of unavailable cores, currently used for offline ones, to
isolated ones:
* A core is unavailable if isolated or offline;
* A core is available if non isolated and online;
A core is considered unavailable as isolated if it belongs to:
* the isolcpus (domain) list
* an isolated cpuset
Except if it is:
* in the nohz_full list (already idle for the hierarchy)
* the nohz timekeeper core (must be available to handle global timers)
CPUs are added to the hierarchy during late boot, excluding isolated
ones, the hierarchy is also adapted when the cpuset isolation changes.
Due to how the timer migration algorithm works, any CPU part of the
hierarchy can have their global timers pulled by remote CPUs and have to
pull remote timers, only skipping pulling remote timers would break the
logic.
For this reason, prevent isolated CPUs from pulling remote global
timers, but also the other way around: any global timer started on an
isolated CPU will run there. This does not break the concept of
isolation (global timers don't come from outside the CPU) and, if
considered inappropriate, can usually be mitigated with other isolation
techniques (e.g. IRQ pinning).
This effect was noticed on a 128 cores machine running oslat on the
isolated cores (1-31,33-63,65-95,97-127). The tool monopolises CPUs,
and the CPU with lowest count in a timer migration hierarchy (here 1
and 65) appears as always active and continuously pulls global timers,
from the housekeeping CPUs. This ends up moving driver work (e.g.
delayed work) to isolated CPUs and causes latency spikes:
before the change:
# oslat -c 1-31,33-63,65-95,97-127 -D 62s
...
Maximum: 1203 10 3 4 ... 5 (us)
after the change:
# oslat -c 1-31,33-63,65-95,97-127 -D 62s
...
Maximum: 10 4 3 4 3 ... 5 (us)
The same behaviour was observed on a machine with as few as 20 cores /
40 threads with isocpus set to: 1-9,11-39 with rtla-osnoise-top.
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: John B. Wyatt IV <jwyatt@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://patch.msgid.link/20251120145653.296659-8-gmonaco@redhat.com
Now we can simplify a code that allocates cpumasks for local needs.
Automatic variables have to be initialized at declaration, or at least
before any possibility for the logic to return, so that compiler
wouldn't try to call an associate destructor function on a random stack
number.
Because cpumask_var_t, depending on the CPUMASK_OFFSTACK config, is
either a pointer or an array, we have to have a macro for initialization.
So define a CPUMASK_VAR_NULL macro, which allows to init struct cpumask
pointer with NULL when CPUMASK_OFFSTACK is enabled, and effectively a
no-op when CPUMASK_OFFSTACK is disabled (initialisation optimised out
with -O2).
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://patch.msgid.link/20251120145653.296659-7-gmonaco@redhat.com
Currently the user can set up isolcpus and nohz_full in such a way that
leaves no housekeeping CPU (i.e. no CPU that is neither domain isolated
nor nohz full). This can be a problem for other subsystems (e.g. the
timer wheel imgration).
Prevent this configuration by invalidating the last setting in case the
union of isolcpus (domain) and nohz_full covers all CPUs.
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Waiman Long <longman@redhat.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://patch.msgid.link/20251120145653.296659-6-gmonaco@redhat.com
update_unbound_workqueue_cpumask() updates unbound workqueues settings
when there's a change in isolated CPUs, but it can be used for other
subsystems requiring updated when isolated CPUs change.
Generalise the name to update_isolation_cpumasks() to prepare for other
functions unrelated to workqueues to be called in that spot.
[longman: Change the function name to update_isolation_cpumasks()]
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Chen Ridong <chenridong@huaweicloud.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://patch.msgid.link/20251120145653.296659-5-gmonaco@redhat.com
Cleanup tmigr_clear_cpu_available() and tmigr_set_cpu_available() to
prepare for easier checks on the available flag.
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251120145653.296659-4-gmonaco@redhat.com
Keep track of the CPUs available for timer migration in a cpumask. This
prepares the ground to generalise the concept of unavailable CPUs.
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251120145653.296659-3-gmonaco@redhat.com
The timer migration hierarchy excludes offline CPUs via the
tmigr_is_not_available function, which is essentially checking the
online bit for the CPU.
Rename the online bit to available and all references in function names
and tracepoint to generalise the concept of available CPUs.
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251120145653.296659-2-gmonaco@redhat.com
Usage of strcpy() can lead to buffer overflows. Therefore, it has been
replaced with strncpy(). The output file path is provided as a parameter
and might be restricted by command-line by default. But this defensive
patch will prevent any potential overflow, making the code more robust
against future changes in input handling.
Testing:
- ran perf test from tools/perf and did not observe any regression with
the earlier code
Signed-off-by: Hrishikesh Suresh <hrishikesh123s@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Like regular output mode, it should honor command line arguments to
limit to a certain type of PMUs or events.
$ perf list -j hw
[
{
"Unit": "cpu",
"Topic": "legacy hardware",
"EventName": "branch-instructions",
"EventType": "Kernel PMU event",
"BriefDescription": "Retired branch instructions [This event is an alias of branches]",
"Encoding": "cpu/event=0xc4\n/"
},
{
"Unit": "cpu",
"Topic": "legacy hardware",
"EventName": "branch-misses",
"EventType": "Kernel PMU event",
"BriefDescription": "Mispredicted branch instructions",
"Encoding": "cpu/event=0xc5\n/"
},
...
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The JSON print state has only one different field (need_sep). Let's
add the default print state to the json state and use it. Then we can
use the 'ps' variable to update the state properly.
This is a preparation for the next commit.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
When --unit option is used, pmu_glob is set to the argument. It should
match with event PMU and display the matching ones only. But it also
shows raw events and metrics after that.
$ perf list --unit tool
List of pre-defined events (to be used in -e or -M):
tool:
core_wide
[1 if not SMT,if SMT are events being gathered on all SMT threads 1 otherwise 0. Unit: tool]
duration_time
[Wall clock interval time in nanoseconds. Unit: tool]
has_pmem
[1 if persistent memory installed otherwise 0. Unit: tool]
num_cores
[Number of cores. A core consists of 1 or more thread,with each thread being associated with a logical Linux CPU. Unit: tool]
num_cpus
[Number of logical Linux CPUs. There may be multiple such CPUs on a core. Unit: tool]
...
rNNN [Raw event descriptor]
cpu/event=0..255,pc,edge,.../modifier [Raw event descriptor]
[(see 'man perf-list' or 'man perf-record' on how to encode it)]
breakpoint//modifier [Raw event descriptor]
cstate_core/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
cstate_pkg/event=0..0xffffffffffffffff/modifier [Raw event descriptor]
drm_i915//modifier [Raw event descriptor]
hwmon_acpitz//modifier [Raw event descriptor]
hwmon_ac//modifier [Raw event descriptor]
hwmon_bat0//modifier [Raw event descriptor]
hwmon_coretemp//modifier [Raw event descriptor]
...
Metric Groups:
Backend: [Grouping from Top-down Microarchitecture Analysis Metrics spreadsheet]
tma_core_bound
[This metric represents fraction of slots where Core non-memory issues were of a bottleneck]
tma_info_core_ilp
[Instruction-Level-Parallelism (average number of uops executed when there is execution) per thread (logical-processor)]
tma_info_memory_l2mpki
[L2 cache true misses per kilo instruction for retired demand loads]
...
This change makes it print the tool PMU events only.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Determine if a metric is default from `perf list --raw-dump $m` eg:
```
$ perf list --raw-dump l1_prefetch_miss_rate
Default4 l1_prefetch_miss_rate
```
If a metric has "not supported" or "no supported events" then ignore
these failures for default metrics. Tidy up the skip/fail messages in
the output to make them easier to spot/read.
```
$ perf list -vv "all metrics"
...
Testing llc_miss_rate
[Ignored llc_miss_rate] failed but as a Default metric this can be expected
Error: No supported events found. The LLC-loads event is not supported.
...
```
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Closes: https://lore.kernel.org/linux-perf-users/20251119104751.51960-1-tmricht@linux.ibm.com/
Reported-by: Namhyung Kim <namhyung@kernel.org>
Reported-by: James Clark <james.clark@linaro.org>
Closes: https://lore.kernel.org/lkml/aRi9xnwdLh3Dir9f@google.com/
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Make sure that all VFIO PCI devices have peer-to-peer capabilities
enables, so we would be able to export their MMIO memory through DMABUF,
VFIO has always supported P2P mappings with itself. VFIO type 1
insecurely reads PFNs directly out of a VMA's PTEs and programs them
into the IOMMU allowing any two VFIO devices to perform P2P to each
other.
All existing VMMs use this capability to export P2P into a VM where
the VM could setup any kind of DMA it likes. Projects like DPDK/SPDK
are also known to make use of this, though less frequently.
As a first step to more properly integrating VFIO with the P2P
subsystem unconditionally enable P2P support for VFIO PCI devices. The
struct p2pdma_provider will act has a handle to the P2P subsystem to
do things like DMA mapping.
While real PCI devices have to support P2P (they can't even tell if an
IOVA is P2P or not) there may be fake PCI devices that may trigger
some kind of catastrophic system failure. To date VFIO has never
tripped up on such a case, but if one is discovered the plan is to add
a PCI quirk and have pcim_p2pdma_init() fail. This will fully block
the broken device throughout any users of the P2P subsystem in the
kernel.
Thus P2P through DMABUF will follow the historical VFIO model and be
unconditionally enabled by vfio-pci.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Alex Mastro <amastro@fb.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20251120-dmabuf-vfio-v9-9-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
