| Age | Commit message (Collapse) | Author |
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For c code:
```c
extern int xx;
void test(void)
{
if (WARN_ONCE(xx, "x"))
__asm__ volatile ("nop":::);
}
```
Clang will generate the following assembly code:
```assemble
test:
movl xx(%rip), %eax // Assume xx == 0 (likely case)
testl %eax, %eax // judge once
je .LBB0_3 // jump to .LBB0_3
testb $1, test.__already_done(%rip)
je .LBB0_2
.LBB0_3:
testl %eax, %eax // judge again
je .LBB0_5 // jump to .LBB0_5
.LBB0_4:
nop
.LBB0_5:
retq
// omit
```
In the above code, `xx == 0` should be a likely case, but in this case,
xx has been judged twice.
Test info:
1. kernel source:
linux-next
commit 9c0826a5d9aa4d52206d ("Add linux-next specific files for 20251107")
2. compiler:
clang: Debian clang version 21.1.4 (8) with
Debian LLD 21.1.4 (compatible with GNU linkers)
3. config:
base on default x86_64_defconfig, and setting:
CONFIG_MITIGATION_RETHUNK=n
CONFIG_STACKPROTECTOR=n
Add unlikely to __ret_cond to help the compiler optimize correctly.
[akpm@linux-foundation.org: undo whitespace changes]
Link: https://lkml.kernel.org/r/20251109083715.24495-1-qq570070308@gmail.com
Signed-off-by: Xie Yuanbin <qq570070308@gmail.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Maninder Singh <maninder1.s@samsung.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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- amend the kernel-doc so the description is decoupled from the
parameter descriptions.
- add a note to explain behaviour for the signed types when supplied
value is the minimum (e.g., INT_MIN for int type).
Link: https://lkml.kernel.org/r/20251106152051.2361551-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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gcc generates horrid code for both ((u64)u32_a * u32_b) and (u64_a +
u32_b). As well as the extra instructions it can generate a lot of spills
to stack (including spills of constant zeros and even multiplies by
constant zero).
mul_u32_u32() already exists to optimise the multiply. Add a similar
add_u64_32() for the addition. Disable both for clang - it generates
better code without them.
Move the 64x64 => 128 multiply into a static inline helper function for
code clarity. No need for the a/b_hi/lo variables, the implicit casts on
the function calls do the work for us. Should have minimal effect on the
generated code.
Use mul_u32_u32() and add_u64_u32() in the 64x64 => 128 multiply in
mul_u64_add_u64_div_u64().
Link: https://lkml.kernel.org/r/20251105201035.64043-8-david.laight.linux@gmail.com
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Reviewed-by: Nicolas Pitre <npitre@baylibre.com>
Cc: Biju Das <biju.das.jz@bp.renesas.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li RongQing <lirongqing@baidu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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The existing mul_u64_u64_div_u64() rounds down, a 'rounding up' variant
needs 'divisor - 1' adding in between the multiply and divide so cannot
easily be done by a caller.
Add mul_u64_add_u64_div_u64(a, b, c, d) that calculates (a * b + c)/d and
implement the 'round down' and 'round up' using it.
Update the x86-64 asm to optimise for 'c' being a constant zero.
Add kerndoc definitions for all three functions.
Link: https://lkml.kernel.org/r/20251105201035.64043-5-david.laight.linux@gmail.com
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Reviewed-by: Nicolas Pitre <npitre@baylibre.com>
Cc: Biju Das <biju.das.jz@bp.renesas.com>
Cc: Borislav Betkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li RongQing <lirongqing@baidu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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The added documentation to u64_to_user_ptr() misspelled the function name.
Fix it.
Link: https://lkml.kernel.org/r/20251104183834.1046584-1-andriy.shevchenko@linux.intel.com
Fixes: 029c896c4105 ("kernel.h: move PTR_IF() and u64_to_user_ptr() to util_macros.h")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexandru Ardelean <aardelean@baylibre.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Align constant definition names with parameters to make it easier to map.
It's also better to maintain and extend the names while keeping their
uniqueness.
Link: https://lkml.kernel.org/r/20251030132007.3742368-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Feng Tang <feng.tang@linux.alibaba.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "make VM_SOFTDIRTY a sticky VMA flag", v2.
Currently we set VM_SOFTDIRTY when a new mapping is set up (whether by
establishing a new VMA, or via merge) as implemented in __mmap_complete()
and do_brk_flags().
However, when performing a merge of existing mappings such as when
performing mprotect(), we may lose the VM_SOFTDIRTY flag.
Now we have the concept of making VMA flags 'sticky', that is that they
both don't prevent merge and, importantly, are propagated to merged VMAs,
this seems a sensible alternative to the existing special-casing of
VM_SOFTDIRTY.
We additionally add a self-test that demonstrates that this logic behaves
as expected.
This patch (of 2):
Currently we set VM_SOFTDIRTY when a new mapping is set up (whether by
establishing a new VMA, or via merge) as implemented in __mmap_complete()
and do_brk_flags().
However, when performing a merge of existing mappings such as when
performing mprotect(), we may lose the VM_SOFTDIRTY flag.
This is because currently we simply ignore VM_SOFTDIRTY for the purposes
of merge, so one VMA may possess the flag and another not, and whichever
happens to be the target VMA will be the one upon which the merge is
performed which may or may not have VM_SOFTDIRTY set.
Now we have the concept of 'sticky' VMA flags, let's make VM_SOFTDIRTY one
which solves this issue.
Additionally update VMA userland tests to propagate changes.
[akpm@linux-foundation.org: update comments, per Lorenzo]
Link: https://lkml.kernel.org/r/0019e0b8-ee1e-4359-b5ee-94225cbe5588@lucifer.local
Link: https://lkml.kernel.org/r/cover.1763399675.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/955478b5170715c895d1ef3b7f68e0cd77f76868.1763399675.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: Andrey Vagin <avagin@gmail.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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DAMOS filters that are handled by the ops layer are linked to
damos->ops_filters. Owing to the ops_ prefix on the name, it is easy to
understand it is for ops layer handled filters. The other types of
filters, which are handled by the core layer, are linked to
damos->filters. Because of the name, it is easy to confuse the list is
there for not only core layer handled ones but all filters. Avoid such
confusions by renaming the field to core_filters.
Link: https://lkml.kernel.org/r/20251112154114.66053-3-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Bill Wendling <morbo@google.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "mm/damon: misc cleanups".
Yet another batch of misc cleanups and refactoring for DAMON code, tests,
and documents.
First two patches (1and 2) rename DAMOS core filters related code for
readability.
Three following patches (3-5) refactor page table walk callback functions
in DAMON, as suggested by Hugh and David, and I promised.
Next two patches (6 and 7) refactor DAMON core layer kunit test and sysfs
interface selftest to be simple and deduplicated.
Final two patches (8 and 9) fix up sphinx and grammatical errors on
documents.
This patch (of 9):
DAMOS filters handled by the core layer are called core filters, while
those handled by the ops layer are called ops filters. They share the
same type but are managed in different places since core filters are
evaluated before the ops filters. They also have different helper
functions that depend on their managed places.
The helper functions for ops filters have '_ops_' keyword on their name,
so it is easy to know they are for ops filters. Meanwhile, the helper
functions for core filters are not having the 'core' keyword on their
name. This makes it easy to be mistakenly used for ops filters. Actually
there was such a bug.
To avoid future mistakes from similar confusions, rename DAMOS core
filters helper functions to have a keyword 'core' on their names.
Link: https://lkml.kernel.org/r/20251112154114.66053-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20251112154114.66053-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Bill Wendling <morbo@google.com>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Patch series "vma_start_write_killable"", v2.
When we added the VMA lock, we made a major oversight in not adding a
killable variant. That can run us into trouble where a thread takes the
VMA lock for read (eg handling a page fault) and then goes out to lunch
for an hour (eg doing reclaim). Another thread tries to modify the VMA,
taking the mmap_lock for write, then attempts to lock the VMA for write.
That blocks on the first thread, and ensures that every other page fault
now tries to take the mmap_lock for read. Because everything's in an
uninterruptible sleep, we can't kill the task, which makes me angry.
This patchset just adds vma_start_write_killable() and converts one caller
to use it. Most users are somewhat tricky to convert, so expect follow-up
individual patches per call-site which need careful analysis to make sure
we've done proper cleanup.
This patch (of 2):
The vma can be held read-locked for a substantial period of time, eg if
memory allocation needs to go into reclaim. It's useful to be able to
send fatal signals to threads which are waiting for the write lock.
Link: https://lkml.kernel.org/r/20251110203204.1454057-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20251110203204.1454057-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Chris Li <chriscli@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Currently kernel dumps memory state on oom and allocation failures. One
of the question usually raised on those dumps is why the kernel has not
reclaimed the reclaimable memory instead of triggering oom. One potential
reason is the usage of memory protection provided by memcg. So, let's
also dump the memory protected by the memcg in such reports to ease the
debugging.
Link: https://lkml.kernel.org/r/20251107234041.3632644-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Gather all the VMA flags whose presence implies that page tables must be
copied on fork into a single bitmap - VM_COPY_ON_FORK - and use this
rather than specifying individual flags in vma_needs_copy().
We also add VM_MAYBE_GUARD to this list, as it being set on a VMA implies
that there may be metadata contained in the page tables (that is - guard
markers) which would will not and cannot be propagated upon fork.
This was already being done manually previously in vma_needs_copy(), but
this makes it very explicit, alongside VM_PFNMAP, VM_MIXEDMAP and
VM_UFFD_WP all of which imply the same.
Note that VM_STICKY flags ought generally to be marked VM_COPY_ON_FORK too
- because equally a flag being VM_STICKY indicates that the VMA contains
metadat that is not propagated by being faulted in - i.e. that the VMA
metadata does not fully describe the VMA alone, and thus we must propagate
whatever metadata there is on a fork.
However, for maximum flexibility, we do not make this necessarily the case
here.
Link: https://lkml.kernel.org/r/5d41b24e7bc622cda0af92b6d558d7f4c0d1bc8c.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>
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: Lance Yang <lance.yang@linux.dev>
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>
|
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It is useful to be able to designate that certain flags are 'sticky', that
is, if two VMAs are merged one with a flag of this nature and one without,
the merged VMA sets this flag.
As a result we ignore these flags for the purposes of determining VMA flag
differences between VMAs being considered for merge.
This patch therefore updates the VMA merge logic to perform this action,
with flags possessing this property being described in the VM_STICKY
bitmap.
Those flags which ought to be ignored for the purposes of VMA merge are
described in the VM_IGNORE_MERGE bitmap, which the VMA merge logic is also
updated to use.
As part of this change we place VM_SOFTDIRTY in VM_IGNORE_MERGE as it
already had this behaviour, alongside VM_STICKY as sticky flags by
implication must not disallow merge.
Ultimately it seems that we should make VM_SOFTDIRTY a sticky flag in its
own right, but this change is out of scope for this series.
The only sticky flag designated as such is VM_MAYBE_GUARD, so as a result
of this change, once the VMA flag is set upon guard region installation,
VMAs with guard ranges will now not have their merge behaviour impacted as
a result and can be freely merged with other VMAs without VM_MAYBE_GUARD
set.
Also update the comments for vma_modify_flags() to directly reference
sticky flags now we have established the concept.
We also update the VMA userland tests to account for the changes.
Link: https://lkml.kernel.org/r/22ad5269f7669d62afb42ce0c79bad70b994c58d.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>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand (Red Hat) <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <lance.yang@linux.dev>
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>
|
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This patch adds the ability to atomically set VMA flags with only the mmap
read/VMA read lock held.
As this could be hugely problematic for VMA flags in general given that
all other accesses are non-atomic and serialised by the mmap/VMA locks, we
implement this with a strict allow-list - that is, only designated flags
are allowed to do this.
We make VM_MAYBE_GUARD one of these flags.
Link: https://lkml.kernel.org/r/97e57abed09f2663077ed7a36fb8206e243171a9.1763460113.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>
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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 8e2f2aeb8b48 ("fs/proc/task_mmu: add guard region bit to
pagemap") and the related commit a516403787e0 ("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 8d0920bde5eb ("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>
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Kill mm_wr_locked since commit f8e97613fed2 ("mm: convert VM_PFNMAP
tracking to pfnmap_track() + pfnmap_untrack()") remove the user.
Link: https://lkml.kernel.org/r/20251104085709.2688433-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: David Hildenbrand (Red Hat) <david@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Since commit 9254c8ae9b81 ("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>
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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
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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>
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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
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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
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These helpers are useful for managing additional references taken
on the device from other associated VFIO modules.
Original-patch-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
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-v9-7-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
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Add dma_buf_phys_vec_to_sgt() and dma_buf_free_sgt() helpers to convert
an array of MMIO physical address ranges into scatter-gather tables with
proper DMA mapping.
These common functions are a starting point and support any PCI
drivers creating mappings from their BAR's MMIO addresses. VFIO is one
case, as shortly will be RDMA. We can review existing DRM drivers to
refactor them separately. We hope this will evolve into routines to
help common DRM that include mixed CPU and MMIO mappings.
Compared to the dma_map_resource() abuse this implementation handles
the complicated PCI P2P scenarios properly, especially when an IOMMU
is enabled:
- Direct bus address mapping without IOVA allocation for
PCI_P2PDMA_MAP_BUS_ADDR, using pci_p2pdma_bus_addr_map(). This
happens if the IOMMU is enabled but the PCIe switch ACS flags allow
transactions to avoid the host bridge.
Further, this handles the slightly obscure, case of MMIO with a
phys_addr_t that is different from the physical BAR programming
(bus offset). The phys_addr_t is converted to a dma_addr_t and
accommodates this effect. This enables certain real systems to
work, especially on ARM platforms.
- Mapping through host bridge with IOVA allocation and DMA_ATTR_MMIO
attribute for MMIO memory regions (PCI_P2PDMA_MAP_THRU_HOST_BRIDGE).
This happens when the IOMMU is enabled and the ACS flags are forcing
all traffic to the IOMMU - ie for virtualization systems.
- Cases where P2P is not supported through the host bridge/CPU. The
P2P subsystem is the proper place to detect this and block it.
Helper functions fill_sg_entry() and calc_sg_nents() handle the
scatter-gather table construction, splitting large regions into
UINT_MAX-sized chunks to fit within sg->length field limits.
Since the physical address based DMA API forbids use of the CPU list
of the scatterlist this will produce a mangled scatterlist that has
a fully zero-length and NULL'd CPU list. The list is 0 length,
all the struct page pointers are NULL and zero sized. This is stronger
and more robust than the existing mangle_sg_table() technique. It is
a future project to migrate DMABUF as a subsystem away from using
scatterlist for this data structure.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.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: Christian König <christian.koenig@amd.com>
Acked-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20251120-dmabuf-vfio-v9-6-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
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Provide an access to pci_p2pdma_map_type() function to allow subsystems
to determine the appropriate mapping type for P2PDMA transfers between
a provider and target device.
The pci_p2pdma_map_type() function is the core P2P layer version of
the existing public, but struct page focused, pci_p2pdma_state()
function. It returns the same result. It is required to use the p2p
subsystem from drivers that don't use the struct page layer.
Like __pci_p2pdma_update_state() it is not an exported function. The
idea is that only subsystem code will implement mapping helpers for
taking in phys_addr_t lists, this is deliberately not made accessible
to every driver to prevent abuse.
Following patches will use this function to implement a shared DMA
mapping helper for DMABUF.
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-v9-4-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
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Refactor the PCI P2PDMA subsystem to separate the core peer-to-peer DMA
functionality from the optional memory allocation layer. This creates a
two-tier architecture:
The core layer provides P2P mapping functionality for physical addresses
based on PCI device MMIO BARs and integrates with the DMA API for
mapping operations. This layer is required for all P2PDMA users.
The optional upper layer provides memory allocation capabilities
including gen_pool allocator, struct page support, and sysfs interface
for user space access.
This separation allows subsystems like DMABUF to use only the core P2P
mapping functionality without the overhead of memory allocation features
they don't need. The core functionality is now available through the
new pcim_p2pdma_provider() function that returns a p2pdma_provider
structure.
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-v9-3-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
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Update the pci_p2pdma_bus_addr_map() function to take a direct pointer
to the p2pdma_provider structure instead of the pci_p2pdma_map_state.
This simplifies the API by removing the need for callers to extract
the provider from the state structure.
The change updates all callers across the kernel (block layer, IOMMU,
DMA direct, and HMM) to pass the provider pointer directly, making
the code more explicit and reducing unnecessary indirection. This
also removes the runtime warning check since callers now have direct
control over which provider they use.
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-v9-2-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
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Currently the P2PDMA code requires a pgmap and a struct page to
function. The was serving three important purposes:
- DMA API compatibility, where scatterlist required a struct page as
input
- Life cycle management, the percpu_ref is used to prevent UAF during
device hot unplug
- A way to get the P2P provider data through the pci_p2pdma_pagemap
The DMA API now has a new flow, and has gained phys_addr_t support, so
it no longer needs struct pages to perform P2P mapping.
Lifecycle management can be delegated to the user, DMABUF for instance
has a suitable invalidation protocol that does not require struct page.
Finding the P2P provider data can also be managed by the caller
without need to look it up from the phys_addr.
Split the P2PDMA code into two layers. The optional upper layer,
effectively, provides a way to mmap() P2P memory into a VMA by
providing struct page, pgmap, a genalloc and sysfs.
The lower layer provides the actual P2P infrastructure and is wrapped
up in a new struct p2pdma_provider. Rework the mmap layer to use new
p2pdma_provider based APIs.
Drivers that do not want to put P2P memory into VMA's can allocate a
struct p2pdma_provider after probe() starts and free it before
remove() completes. When DMA mapping the driver must convey the struct
p2pdma_provider to the DMA mapping code along with a phys_addr of the
MMIO BAR slice to map. The driver must ensure that no DMA mapping
outlives the lifetime of the struct p2pdma_provider.
The intended target of this new API layer is DMABUF. There is usually
only a single p2pdma_provider for a DMABUF exporter. Most drivers can
establish the p2pdma_provider during probe, access the single instance
during DMABUF attach and use that to drive the DMA mapping.
DMABUF provides an invalidation mechanism that can guarantee all DMA
is halted and the DMA mappings are undone prior to destroying the
struct p2pdma_provider. This ensures there is no UAF through DMABUFs
that are lingering past driver removal.
The new p2pdma_provider layer cannot be used to create P2P memory that
can be mapped into VMA's, be used with pin_user_pages(), O_DIRECT, and
so on. These use cases must still use the mmap() layer. The
p2pdma_provider layer is principally for DMABUF-like use cases where
DMABUF natively manages the life cycle and access instead of
vmas/pin_user_pages()/struct page.
In addition, remove the bus_off field from pci_p2pdma_map_state since
it duplicates information already available in the pgmap structure.
The bus_offset is only used in one location (pci_p2pdma_bus_addr_map)
and is always identical to pgmap->bus_offset.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.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-v9-1-d7f71607f371@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
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into gpio/for-next
Reset/GPIO/swnode changes for v6.19
* Extend software node implementation, allowing its properties to reference
existing firmware nodes.
* Update the GPIO property interface to use reworked swnode macros.
* Rework reset-gpio code to use GPIO lookup via swnode.
* Fix spi-cs42l43 driver to work with swnode changes.
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Add a device level driver as the entry point for the class driver.
Additional auxiliary drivers will be registered to support each function
within the device. This driver will register those function drivers and
provide the device level functionality, such as monitoring bus
attach/detach, the device level register map, and the root for the IRQ
handling.
Co-developed-by: Maciej Strozek <mstrozek@opensource.cirrus.com>
Tested-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Maciej Strozek <mstrozek@opensource.cirrus.com>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Tested-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20251120153023.2105663-13-ckeepax@opensource.cirrus.com
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
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Cross-merge networking fixes after downstream PR (net-6.18-rc7).
No conflicts, adjacent changes:
tools/testing/selftests/net/af_unix/Makefile
e1bb28bf13f4 ("selftest: af_unix: Add test for SO_PEEK_OFF.")
45a1cd8346ca ("selftests: af_unix: Add tests for ECONNRESET and EOF semantics")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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cpuset_cpus_allowed() uses a reader lock that is sleepable under RT,
which means it cannot be called inside raw_spin_lock_t context.
Introduce a new cpuset_cpus_allowed_locked() helper that performs the
same function as cpuset_cpus_allowed() except that the caller must have
acquired the cpuset_mutex so that no further locking will be needed.
Suggested-by: Waiman Long <longman@redhat.com>
Signed-off-by: Pingfan Liu <piliu@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: linux-kernel@vger.kernel.org
To: cgroups@vger.kernel.org
Reviewed-by: Chen Ridong <chenridong@huawei.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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At the moment software nodes can only reference other software nodes.
This is a limitation for devices created, for instance, on the auxiliary
bus with a dynamic software node attached which cannot reference devices
the firmware node of which is "real" (as an OF node or otherwise).
Make it possible for a software node to reference all firmware nodes in
addition to static software nodes. To that end: add a second pointer to
struct software_node_ref_args of type struct fwnode_handle. The core
swnode code will first check the swnode pointer and if it's NULL, it
will assume the fwnode pointer should be set.
Software node graphs remain the same, as in: the remote endpoints still
have to be software nodes.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Tested-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
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Bean Huo <beanhuo@iokpp.de> says:
This patch series introduces OP-TEE based RPMB (Replay Protected
Memory Block) support for UFS devices, extending the kernel-level
secure storage capabilities that are currently available for eMMC
devices.
Previously, OP-TEE required a userspace supplicant to access RPMB
partitions, which created complex dependencies and reliability issues,
especially during early boot scenarios. Recent work by Linaro has
moved core supplicant functionality directly into the Linux kernel for
eMMC devices, eliminating userspace dependencies and enabling
immediate secure storage access. This series extends the same approach
to UFS devices, which are used in enterprise and mobile applications
that require secure storage capabilities.
Benefits:
- Eliminates dependency on userspace supplicant for UFS RPMB access
- Enables early boot secure storage access (e.g., fTPM, secure UEFI
variables)
- Provides kernel-level RPMB access as soon as UFS driver is
initialized
- Removes complex initramfs dependencies and boot ordering
requirements
- Ensures reliable and deterministic secure storage operations
- Supports both built-in and modular fTPM configurations.
Prerequisites:
--------------
This patch series depends on commit 7e8242405b94 ("rpmb: move struct
rpmb_frame to common header") which has been merged into mainline
v6.18-rc2.
Link: https://patch.msgid.link/20251107230518.4060231-1-beanhuo@iokpp.de
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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min_t(unsigned int, a, b) casts an 'unsigned long' to 'unsigned int'.
Use min(a, b) instead as it promotes any 'unsigned int' to 'unsigned long'
and so cannot discard significant bits.
In this case the 'unsigned long' value is small enough that the result
is ok.
Detected by an extra check added to min_t().
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
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Currently, there are many pieces of nearly identical code scattered across
different places. Consolidate the duplicate code into helper functions to
improve maintainability and reduce the likelihood of errors.
Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev>
Link: https://patch.msgid.link/20251115134753.179931-2-yuntao.wang@linux.dev
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
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strends() kernel doc should have used `@str:` format for arguments
instead of `@str -`.
Fixes: 197b3f3c70d6 ("string: provide strends()")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/all/20251118134748.40f03b9c@canb.auug.org.au/
Link: https://lore.kernel.org/r/20251118-strends-follow-up-v1-1-d3f8ef750f59@linaro.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
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cs_dsp_debugfs_wmfw_read() and cs_dsp_debugfs_bin_read() were identical
except for which struct member they printed. Move all this duplicated
code into a common function cs_dsp_debugfs_string_read().
The check for dsp->booted has been removed because this is redundant.
The two strings are set when the DSP is booted and cleared when the
DSP is powered-down.
Access to the string char * must be protected by the pwr_lock mutex. The
string is passed into cs_dsp_debugfs_string_read() as a pointer to the
char * so that the mutex lock can also be factored out into
cs_dsp_debugfs_string_read().
wmfw_file_name and bin_file_name members of struct cs_dsp have been
changed to const char *. It makes for a better API to pass a const
pointer into cs_dsp_debugfs_string_read().
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20251120130640.1169780-2-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
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Merge series from Bartosz Golaszewski <brgl@bgdev.pl>:
Problem statement: GPIOs are implemented as a strictly exclusive
resource in the kernel but there are lots of platforms on which single
pin is shared by multiple devices which don't communicate so need some
way of properly sharing access to a GPIO. What we have now is the
GPIOD_FLAGS_BIT_NONEXCLUSIVE flag which was introduced as a hack and
doesn't do any locking or arbitration of access - it literally just hand
the same GPIO descriptor to all interested users.
The proposed solution is composed of three major parts: the high-level,
shared GPIO proxy driver that arbitrates access to the shared pin and
exposes a regular GPIO chip interface to consumers, a low-level shared
GPIOLIB module that scans firmware nodes and creates auxiliary devices
that attach to the proxy driver and finally a set of core GPIOLIB
changes that plug the former into the GPIO lookup path.
The changes are implemented in a way that allows to seamlessly compile
out any code related to sharing GPIOs for systems that don't need it.
The practical use-case for this are the powerdown GPIOs shared by
speakers on Qualcomm db845c platform, however I have also extensively
tested it using gpio-virtuser on arm64 qemu with various DT
configurations.
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Commit cf3fc037623c ("ata: libata-scsi: Fix ata_to_sense_error() status
handling") fixed ata_to_sense_error() to properly generate sense key
ABORTED COMMAND (without any additional sense code), instead of the
previous bogus sense key ILLEGAL REQUEST with the additional sense code
UNALIGNED WRITE COMMAND, for a failed command.
However, this broke suspend for Security locked drives (drives that have
Security enabled, and have not been Security unlocked by boot firmware).
The reason for this is that the SCSI disk driver, for the Synchronize
Cache command only, treats any sense data with sense key ILLEGAL REQUEST
as a successful command (regardless of ASC / ASCQ).
After commit cf3fc037623c ("ata: libata-scsi: Fix ata_to_sense_error()
status handling") the code that treats any sense data with sense key
ILLEGAL REQUEST as a successful command is no longer applicable, so the
command fails, which causes the system suspend to be aborted:
sd 1:0:0:0: PM: dpm_run_callback(): scsi_bus_suspend returns -5
sd 1:0:0:0: PM: failed to suspend async: error -5
PM: Some devices failed to suspend, or early wake event detected
To make suspend work once again, for a Security locked device only,
return sense data LOGICAL UNIT ACCESS NOT AUTHORIZED, the actual sense
data which a real SCSI device would have returned if locked.
The SCSI disk driver treats this sense data as a successful command.
Cc: stable@vger.kernel.org
Reported-by: Ilia Baryshnikov <qwelias@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220704
Fixes: cf3fc037623c ("ata: libata-scsi: Fix ata_to_sense_error() status handling")
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
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CID management OR's two cpumasks and then calculates the weight on the
result. That's inefficient as that has to walk the same stuff twice. As
this is done with runqueue lock held, there is a real benefit of speeding
this up. Depending on the system this results in 10-20% less cycles spent
with runqueue lock held for a 4K cpumask.
Provide cpumask_weighted_or() and the corresponding bitmap functions which
return the weight of the OR result right away.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251119172549.448263340@linutronix.de
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This is only used in the scheduler core code, so there is no point to have
it in a global header.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Link: https://patch.msgid.link/20251119172549.321259077@linutronix.de
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Both the per CPU storage and the data in mm_struct are heavily used in
context switch. As they can end up next to other frequently modified data,
they are subject to false sharing.
Make them cache line aligned.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251119172549.194111661@linutronix.de
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Having a lot of CID functionality specific members in struct task_struct
and struct mm_struct is not really making the code easier to read.
Encapsulate the CID specific parts in data structures and keep them
separate from the stuff they are embedded in.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251119172549.131573768@linutronix.de
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The CID management is a complex beast, which affects both scheduling and
task migration. The compaction mechanism forces random tasks of a process
into task work on exit to user space causing latency spikes.
Revert back to the initial simple bitmap allocating mechanics, which are
known to have scalability issues as that allows to gradually build up a
replacement functionality in a reviewable way.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251119172549.068197830@linutronix.de
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The added struct is needed when writing generic handler for both CMAC-128
and CMAC-256.
Signed-off-by: Chien Wong <m@xv97.com>
Link: https://patch.msgid.link/20251113140511.48658-3-m@xv97.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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On S2MPG10 (and similar like S2MPG11), top-level interrupt status and
mask registers exist which need to be unmasked to get the PMIC
interrupts. This additional status doesn't seem to exist on other PMICs
in the S2MP* family, and the S2MPG10 driver is manually dealing with
masking and unmasking currently.
The correct approach here is to register this hierarchy as chained
interrupts, though, without any additional manual steps. Doing so will
also simplify addition of other, similar, PMICs (like S2MPG11) in the
future.
Update the driver to do just that.
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20251114-s2mpg10-chained-irq-v1-1-34ddfa49c4cd@linaro.org
Signed-off-by: Lee Jones <lee@kernel.org>
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Add IEEE80211_6GHZ_CTRL_REG_AP_ROLE_NOT_RELEVANT
and map it to IEEE80211_REG_LPI_AP for safe regulatory compliance
when AP role classification is not applicable.
Use LPI as safe fallback to prevent power limit violations.
Signed-off-by: Pagadala Yesu Anjaneyulu <pagadala.yesu.anjaneyulu@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20251112110828.856283677cc7.I36138a34847c3b4e680974bf347dde844448f3bc@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Merge series from Bartosz Golaszewski <brgl@bgdev.pl>:
Problem statement: GPIOs are implemented as a strictly exclusive
resource in the kernel but there are lots of platforms on which single
pin is shared by multiple devices which don't communicate so need some
way of properly sharing access to a GPIO. What we have now is the
GPIOD_FLAGS_BIT_NONEXCLUSIVE flag which was introduced as a hack and
doesn't do any locking or arbitration of access - it literally just hand
the same GPIO descriptor to all interested users.
The proposed solution is composed of three major parts: the high-level,
shared GPIO proxy driver that arbitrates access to the shared pin and
exposes a regular GPIO chip interface to consumers, a low-level shared
GPIOLIB module that scans firmware nodes and creates auxiliary devices
that attach to the proxy driver and finally a set of core GPIOLIB
changes that plug the former into the GPIO lookup path.
The changes are implemented in a way that allows to seamlessly compile
out any code related to sharing GPIOs for systems that don't need it.
The practical use-case for this are the powerdown GPIOs shared by
speakers on Qualcomm db845c platform, however I have also extensively
tested it using gpio-virtuser on arm64 qemu with various DT
configurations.
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|
Pull 6.18-devel branch for applying the further HD-audio fixups for HP.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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