| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
Pull drm fixes from Dave Airlie:
"Weekly fixes pull.
There is one mm fix in here for a HMM livelock triggered by the xe
driver tests. Otherwise it's a pretty wide range of fixes across the
board, ttm UAF regression fix, amdgpu fixes, nouveau doesn't crash my
laptop anymore fix, and a fair bit of misc.
Seems about right for rc3.
mm:
- mm: Fix a hmm_range_fault() livelock / starvation problem
pagemap:
- Revert "drm/pagemap: Disable device-to-device migration"
ttm:
- fix function return breaking reclaim
- fix build failure on PREEMPT_RT
- fix bo->resource UAF
dma-buf:
- include ioctl.h in uapi header
sched:
- fix kernel doc warning
amdgpu:
- LUT fixes
- VCN5 fix
- Dispclk fix
- SMU 13.x fix
- Fix race in VM acquire
- PSP 15.x fix
- UserQ fix
amdxdna:
- fix invalid payload for failed command
- fix NULL ptr dereference
- fix major fw version check
- avoid inconsistent fw state on error
i915/display:
- Fix for Lenovo T14 G7 display not refreshing
xe:
- Do not preempt fence signaling CS instructions
- Some leak and finalization fixes
- Workaround fix
nouveau:
- avoid runtime suspend oops when using dp aux
panthor:
- fix gem_sync argument ordering
solomon:
- fix incorrect display output
renesas:
- fix DSI divider programming
ethosu:
- fix job submit error clean-up refcount
- fix NPU_OP_ELEMENTWISE validation
- handle possible underflows in IFM size calcs"
* tag 'drm-fixes-2026-03-07' of https://gitlab.freedesktop.org/drm/kernel: (38 commits)
accel: ethosu: Handle possible underflow in IFM size calculations
accel: ethosu: Fix NPU_OP_ELEMENTWISE validation with scalar
accel: ethosu: Fix job submit error clean-up refcount underflows
accel/amdxdna: Split mailbox channel create function
drm/panthor: Correct the order of arguments passed to gem_sync
Revert "drm/syncobj: Fix handle <-> fd ioctls with dirty stack"
drm/ttm: Fix bo resource use-after-free
nouveau/dpcd: return EBUSY for aux xfer if the device is asleep
accel/amdxdna: Fix major version check on NPU1 platform
drm/amdgpu/userq: refcount userqueues to avoid any race conditions
drm/amdgpu/userq: Consolidate wait ioctl exit path
drm/amdgpu/psp: Use Indirect access address for GFX to PSP mailbox
drm/amdgpu: Fix use-after-free race in VM acquire
drm/amd/pm: remove invalid gpu_metrics.energy_accumulator on smu v13.0.x
drm/xe: Fix memory leak in xe_vm_madvise_ioctl
drm/xe/reg_sr: Fix leak on xa_store failure
drm/xe/xe2_hpg: Correct implementation of Wa_16025250150
drm/xe/gsc: Fix GSC proxy cleanup on early initialization failure
Revert "drm/pagemap: Disable device-to-device migration"
drm/i915/psr: Fix for Panel Replay X granularity DPCD register handling
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Fix for slab->stride truncation on 64k page systems due to short
type. It was not due to races and lack of barriers in the end. (Harry
Yoo)
- Fix for severe performance regression due to unnecessary sheaf refill
restrictions exposed by mempool allocation strategy. (Vlastimil
Babka)
- Stable fix for potential silent percpu sheaf flushing failures on
PREEMPT_RT. (Vlastimil Babka)
* tag 'slab-for-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab: change stride type from unsigned short to unsigned int
mm/slab: allow sheaf refill if blocking is not allowed
slab: distinguish lock and trylock for sheaf_flush_main()
|
|
This came up as a result of the tracing fix pull request, and commit
e39bb9e02b68 ("tracing: Fix WARN_ON in tracing_buffers_mmap_close") in
particular.
The use of MADV_DOFORK confused the ring buffer mapping reference
counting just because it was unexpected, since the mapping was
originally done with VM_DONTCOPY.
The tracing code may well be the only case of this (and fixed it all by
just using the mmap open callback to unconfuse itself), but it's just
strange that we allow MADV_DOFORK on special mappings where the kernel
has set the "don't copy this" bit.
The code already disallowed it for VM_IO mappings (going back to the
original commit f822566165dd: "madvise MADV_DONTFORK/MADV_DOFORK"), so
just extend it to any of the VM_SPECIAL cases (which includes
VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP in addition to VM_IO).
We could also allow MADV_DOFORK only on mappings that had been marked
DONTFORK by the user. But that would require us to track that
(presumably with another VM_xyz bit), so let's just do this trivial and
straightforward modifications.
If anybody notices, Lorenzo will be boarding Flying Pig Airlines.
Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Link: https://lore.kernel.org/all/a8907468-d7e9-4727-af28-66d905093230@kernel.org/
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Commit 7a8e71bc619d ("mm/slab: use stride to access slabobj_ext")
defined the type of slab->stride as unsigned short, because the author
initially planned to store stride within the lower 16 bits of the
page_type field, but later stored it in unused bits in the counters
field instead.
However, the idea of having only 2-byte stride turned out to be a
serious mistake. On systems with 64k pages, order-1 pages are 128k,
which is larger than USHRT_MAX. It triggers a debug warning because
s->size is 128k while stride, truncated to 2 bytes, becomes zero:
------------[ cut here ]------------
Warning! stride (0) != s->size (131072)
WARNING: mm/slub.c:2231 at alloc_slab_obj_exts_early.constprop.0+0x524/0x534, CPU#6: systemd-sysctl/307
Modules linked in:
CPU: 6 UID: 0 PID: 307 Comm: systemd-sysctl Not tainted 7.0.0-rc1+ #6 PREEMPTLAZY
Hardware name: IBM,9009-22A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW950.E0 (VL950_179) hv:phyp pSeries
NIP: c0000000008a9ac0 LR: c0000000008a9abc CTR: 0000000000000000
REGS: c0000000141f7390 TRAP: 0700 Not tainted (7.0.0-rc1+)
MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 28004400 XER: 00000005
CFAR: c000000000279318 IRQMASK: 0
GPR00: c0000000008a9abc c0000000141f7630 c00000000252a300 c00000001427b200
GPR04: 0000000000000004 0000000000000000 c000000000278fd0 0000000000000000
GPR08: fffffffffffe0000 0000000000000000 0000000000000000 0000000022004400
GPR12: c000000000f644b0 c000000017ff8f00 0000000000000000 0000000000000000
GPR16: 0000000000000000 c0000000141f7aa0 0000000000000000 c0000000141f7a88
GPR20: 0000000000000000 0000000000400cc0 ffffffffffffffff c00000001427b180
GPR24: 0000000000000004 00000000000c0cc0 c000000004e89a20 c00000005de90011
GPR28: 0000000000010010 c00000005df00000 c000000006017f80 c00c000000177a00
NIP [c0000000008a9ac0] alloc_slab_obj_exts_early.constprop.0+0x524/0x534
LR [c0000000008a9abc] alloc_slab_obj_exts_early.constprop.0+0x520/0x534
Call Trace:
[c0000000141f7630] [c0000000008a9abc] alloc_slab_obj_exts_early.constprop.0+0x520/0x534 (unreliable)
[c0000000141f76c0] [c0000000008aafbc] allocate_slab+0x154/0x94c
[c0000000141f7760] [c0000000008b41c0] refill_objects+0x124/0x16c
[c0000000141f77c0] [c0000000008b4be0] __pcs_replace_empty_main+0x2b0/0x444
[c0000000141f7810] [c0000000008b9600] __kvmalloc_node_noprof+0x840/0x914
[c0000000141f7900] [c000000000a3dd40] seq_read_iter+0x60c/0xb00
[c0000000141f7a10] [c000000000b36b24] proc_reg_read_iter+0x154/0x1fc
[c0000000141f7a50] [c0000000009cee7c] vfs_read+0x39c/0x4e4
[c0000000141f7b30] [c0000000009d0214] ksys_read+0x9c/0x180
[c0000000141f7b90] [c00000000003a8d0] system_call_exception+0x1e0/0x4b0
[c0000000141f7e50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec
This leads to slab_obj_ext() returning the first slabobj_ext or all
objects and confuses the reference counting of object cgroups [1] and
memory (un)charging for memory cgroups [2].
Fortunately, the counters field has 32 unused bits instead of 16
on 64-bit CPUs, which is wide enough to hold any value of s->size.
Change the type to unsigned int.
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Closes: https://lore.kernel.org/lkml/ca241daa-e7e7-4604-a48d-de91ec9184a5@linux.ibm.com [1]
Closes: https://lore.kernel.org/all/ddff7c7d-c0c3-4780-808f-9a83268bbf0c@linux.ibm.com [2]
Fixes: 7a8e71bc619d ("mm/slab: use stride to access slabobj_ext")
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260303135722.2680521-1-harry.yoo@oracle.com
Reviewed-by: Hao Li <hao.li@linux.dev>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
Ming Lei reported [1] a regression in the ublk null target benchmark due
to sheaves. The profile shows that the alloc_from_pcs() fastpath fails
and allocations fall back to ___slab_alloc(). It also shows the
allocations happen through mempool_alloc().
The strategy of mempool_alloc() is to call the underlying allocator
(here slab) without __GFP_DIRECT_RECLAIM first. This does not play well
with __pcs_replace_empty_main() checking for gfpflags_allow_blocking()
to decide if it should refill an empty sheaf or fallback to the
slowpath, so we end up falling back.
We could change the mempool strategy but there might be other paths
doing the same ting. So instead allow sheaf refill when blocking is not
allowed, changing the condition to gfpflags_allow_spinning(). The
original condition was unnecessarily restrictive.
Note this doesn't fully resolve the regression [1] as another component
of that are memoryless nodes, which is to be addressed separately.
Reported-by: Ming Lei <ming.lei@redhat.com>
Fixes: e47c897a2949 ("slab: add sheaves to most caches")
Link: https://lore.kernel.org/all/aZ0SbIqaIkwoW2mB@fedora/ [1]
Link: https://patch.msgid.link/20260302095536.34062-2-vbabka@kernel.org
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
If hmm_range_fault() fails a folio_trylock() in do_swap_page,
trying to acquire the lock of a device-private folio for migration,
to ram, the function will spin until it succeeds grabbing the lock.
However, if the process holding the lock is depending on a work
item to be completed, which is scheduled on the same CPU as the
spinning hmm_range_fault(), that work item might be starved and
we end up in a livelock / starvation situation which is never
resolved.
This can happen, for example if the process holding the
device-private folio lock is stuck in
migrate_device_unmap()->lru_add_drain_all()
sinc lru_add_drain_all() requires a short work-item
to be run on all online cpus to complete.
A prerequisite for this to happen is:
a) Both zone device and system memory folios are considered in
migrate_device_unmap(), so that there is a reason to call
lru_add_drain_all() for a system memory folio while a
folio lock is held on a zone device folio.
b) The zone device folio has an initial mapcount > 1 which causes
at least one migration PTE entry insertion to be deferred to
try_to_migrate(), which can happen after the call to
lru_add_drain_all().
c) No or voluntary only preemption.
This all seems pretty unlikely to happen, but indeed is hit by
the "xe_exec_system_allocator" igt test.
Resolve this by waiting for the folio to be unlocked if the
folio_trylock() fails in do_swap_page().
Rename migration_entry_wait_on_locked() to
softleaf_entry_wait_unlock() and update its documentation to
indicate the new use-case.
Future code improvements might consider moving
the lru_add_drain_all() call in migrate_device_unmap() to be
called *after* all pages have migration entries inserted.
That would eliminate also b) above.
v2:
- Instead of a cond_resched() in hmm_range_fault(),
eliminate the problem by waiting for the folio to be unlocked
in do_swap_page() (Alistair Popple, Andrew Morton)
v3:
- Add a stub migration_entry_wait_on_locked() for the
!CONFIG_MIGRATION case. (Kernel Test Robot)
v4:
- Rename migrate_entry_wait_on_locked() to
softleaf_entry_wait_on_locked() and update docs (Alistair Popple)
v5:
- Add a WARN_ON_ONCE() for the !CONFIG_MIGRATION
version of softleaf_entry_wait_on_locked().
- Modify wording around function names in the commit message
(Andrew Morton)
Suggested-by: Alistair Popple <apopple@nvidia.com>
Fixes: 1afaeb8293c9 ("mm/migrate: Trylock device page in do_swap_page")
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: linux-mm@kvack.org
Cc: <dri-devel@lists.freedesktop.org>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: <stable@vger.kernel.org> # v6.15+
Reviewed-by: John Hubbard <jhubbard@nvidia.com> #v3
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Link: https://patch.msgid.link/20260210115653.92413-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit a69d1ab971a624c6f112cea61536569d579c3215)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
|
|
sheaf_flush_main() can be called from __pcs_replace_full_main() where
it's fine if the trylock fails, and pcs_flush_all() where it's not
expected to and for some flush callers (when destroying the cache or
memory hotremove) it would be actually a problem if it failed and left
the main sheaf not flushed. The flush callers can however safely use
local_lock() instead of trylock.
The trylock failure should not happen in practice on !PREEMPT_RT, but
can happen on PREEMPT_RT. The impact is limited in practice because when
a trylock fails in the kmem_cache_destroy() path, it means someone is
using the cache while destroying it, which is a bug on its own. The memory
hotremove path is unlikely to be employed in a production RT config, but
it's possible.
To fix this, split the function into sheaf_flush_main() (using
local_lock()) and sheaf_try_flush_main() (using local_trylock()) where
both call __sheaf_flush_main_batch() to flush a single batch of objects.
This will also allow lockdep to verify our context assumptions.
The problem was raised in an off-list question by Marcelo.
Fixes: 2d517aa09bbc ("slab: add opt-in caching layer of percpu sheaves")
Cc: stable@vger.kernel.org
Reported-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Hao Li <hao.li@linux.dev>
Link: https://patch.msgid.link/20260211-b4-sheaf-flush-v1-1-4e7f492f0055@suse.cz
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Fix for spurious page allocation warnings on sheaf refill (Harry Yoo)
- Fix for CONFIG_MEM_ALLOC_PROFILING_DEBUG warnings (Suren
Baghdasaryan)
- Fix for kernel-doc warning on ksize() (Sanjay Chitroda)
- Fix to avoid setting slab->stride later than on slab allocation.
Doesn't yet fix the reports from powerpc; debugging is making
progress (Harry Yoo)
* tag 'slab-for-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab: initialize slab->stride early to avoid memory ordering issues
mm/slub: drop duplicate kernel-doc for ksize()
mm/slab: mark alloc tags empty for sheaves allocated with __GFP_NO_OBJ_EXT
mm/slab: pass __GFP_NOWARN to refill_sheaf() if fallback is available
|
|
When alloc_slab_obj_exts() is called later (instead of during slab
allocation and initialization), slab->stride and slab->obj_exts are
updated after the slab is already accessible by multiple CPUs.
The current implementation does not enforce memory ordering between
slab->stride and slab->obj_exts. For correctness, slab->stride must be
visible before slab->obj_exts. Otherwise, concurrent readers may observe
slab->obj_exts as non-zero while stride is still stale.
With stale slab->stride, slab_obj_ext() could return the wrong obj_ext.
This could cause two problems:
- obj_cgroup_put() is called on the wrong objcg, leading to
a use-after-free due to incorrect reference counting [1] by
decrementing the reference count more than it was incremented.
- refill_obj_stock() is called on the wrong objcg, leading to
a page_counter overflow [2] by uncharging more memory than charged.
Fix this by unconditionally initializing slab->stride in
alloc_slab_obj_exts_early(), before the need_slab_obj_exts() check.
In the case of SLAB_OBJ_EXT_IN_OBJ, it is overridden in the function.
This ensures updates to slab->stride become visible before the slab
can be accessed by other CPUs via the per-node partial slab list
(protected by spinlock with acquire/release semantics).
Thanks to Shakeel Butt for pointing out this issue [3].
[vbabka@kernel.org: the bug reports [1] and [2] are not yet fully fixed,
with investigation ongoing, but it is nevertheless a step in the right
direction to only set stride once after allocating the slab and not
change it later ]
Fixes: 7a8e71bc619d ("mm/slab: use stride to access slabobj_ext")
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Link: https://lore.kernel.org/lkml/ca241daa-e7e7-4604-a48d-de91ec9184a5@linux.ibm.com [1]
Link: https://lore.kernel.org/all/ddff7c7d-c0c3-4780-808f-9a83268bbf0c@linux.ibm.com [2]
Link: https://lore.kernel.org/linux-mm/aZu9G9mVIVzSm6Ft@hyeyoo [3]
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
alloc_empty_sheaf() allocates sheaves from SLAB_KMALLOC caches using
__GFP_NO_OBJ_EXT to avoid recursion, however it does not mark their
allocation tags empty before freeing, which results in a warning when
CONFIG_MEM_ALLOC_PROFILING_DEBUG is set. Fix this by marking allocation
tags for such sheaves as empty.
The problem was technically introduced in commit 4c0a17e28340 but only
becomes possible to hit with commit 913ffd3a1bf5.
Fixes: 4c0a17e28340 ("slab: prevent recursive kmalloc() in alloc_empty_sheaf()")
Fixes: 913ffd3a1bf5 ("slab: handle kmalloc sheaves bootstrap")
Reported-by: David Wang <00107082@163.com>
Closes: https://lore.kernel.org/all/20260223155128.3849-1-00107082@163.com/
Analyzed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: David Wang <00107082@163.com>
Link: https://patch.msgid.link/20260225163407.2218712-1-surenb@google.com
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
When refill_sheaf() is called, failing to refill the sheaf doesn't
necessarily mean the allocation will fail because a fallback path
might be available and serve the allocation request.
Suppress spurious warnings by passing __GFP_NOWARN along with
__GFP_NOMEMALLOC whenever a fallback path is available.
When the caller is alloc_full_sheaf() or __pcs_replace_empty_main(),
the kernel always falls back to the slowpath (__slab_alloc_node()).
For __prefill_sheaf_pfmemalloc(), the fallback path is available
only when gfp_pfmemalloc_allowed() returns true.
Reported-and-tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Closes: https://lore.kernel.org/linux-mm/aZt2-oS9lkmwT7Ch@debian.local
Fixes: 1ce20c28eafd ("slab: handle pfmemalloc slabs properly with sheaves")
Link: https://lore.kernel.org/linux-mm/aZwSreGj9-HHdD-j@hyeyoo
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260223133322.16705-1-harry.yoo@oracle.com
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
|
|
Commit d49004c5f0c1 ("arch, mm: consolidate initialization of nodes, zones
and memory map") moved free_area_init() from setup_arch() to
mm_core_init_early(), which runs after setup_arch() returns.
This changed the ordering relative to init_cpu_to_node() on x86. Before
the commit, free_area_init() ran during paging_init() (called from
setup_arch()) *before* init_cpu_to_node(). After the commit, it runs
*after* init_cpu_to_node().
On machines with memoryless NUMA nodes (e.g., node 0 has CPUs but no
memory), this causes a NULL pointer dereference:
1. numa_register_nodes() skips memoryless nodes: no alloc_node_data()
and no node_set_online() for them.
2. init_cpu_to_node() sets memoryless nodes online (they have CPUs)
but does not allocate NODE_DATA.
3. free_area_init() checks "if (!node_online(nid))" to decide whether
to call alloc_offline_node_data(). Since the memoryless node is now
online, the allocation is skipped, leaving NODE_DATA(nid) == NULL.
4. The immediate "pgdat = NODE_DATA(nid)" dereferences NULL.
The crash happens before console_init(), so no output is visible without
earlyprintk. With earlyprintk enabled, the following panic is observed:
BUG: unable to handle page fault for address: 000000000002a1e0
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:free_area_init_node+0x3a/0x540
Call Trace:
<TASK>
free_area_init+0x331/0x4e0
start_kernel+0x69/0x4a0
x86_64_start_reservations+0x24/0x30
x86_64_start_kernel+0x125/0x130
common_startup_64+0x13e/0x148
</TASK>
Kernel panic - not syncing: Attempted to kill the idle task!
Fix this by checking "if (!NODE_DATA(nid))" instead of "if
(!node_online(nid))". This directly tests whether the per-node data
structure needs to be allocated, regardless of the node's online status.
This change is also safe for non-x86 architectures as they all allocate
NODE_DATA for every node including memoryless ones, so the check simply
evaluates to false with no change in behavior.
Link: https://lkml.kernel.org/r/20260222115702.3659-1-ming.lei@redhat.com
Fixes: d49004c5f0c1 ("arch, mm: consolidate initialization of nodes, zones and memory map")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When KASAN hardware tags are enabled, re-enabling KFENCE late (via
/sys/module/kfence/parameters/sample_interval) causes KASAN faults.
This happens because the KFENCE pool and metadata are allocated via the
page allocator, which tags the memory, while KFENCE continues to access it
using untagged pointers during initialization.
Use __GFP_SKIP_KASAN for late KFENCE pool and metadata allocations to
ensure the memory remains untagged, consistent with early allocations from
memblock. To support this, add __GFP_SKIP_KASAN to the allowlist in
__alloc_contig_verify_gfp_mask().
Link: https://lkml.kernel.org/r/20260220144940.2779209-1-glider@google.com
Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure")
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Ernesto Martinez Garcia <ernesto.martinezgarcia@tugraz.at>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
DAMON core uses min_region_sz parameter value as the DAMON region
alignment. The alignment is made using ALIGN() and ALIGN_DOWN(), which
support only the power of two alignments. But DAMON core API callers can
set min_region_sz to an arbitrary number. Users can also set it
indirectly, using addr_unit.
When the alignment is not properly set, DAMON behavior becomes difficult
to expect and understand, makes it effectively broken. It doesn't cause a
kernel crash-like significant issue, though.
Fix the issue by disallowing min_region_sz input that is not a power of
two. Add the check to damon_commit_ctx(), as all DAMON API callers who
set min_region_sz uses the function.
This can be a sort of behavioral change, but it does not break users, for
the following reasons. As the symptom is making DAMON effectively broken,
it is not reasonable to believe there are real use cases of non-power of
two min_region_sz. There is no known use case or issue reports from the
setup, either.
In future, if we find real use cases of non-power of two alignments and we
can support it with low enough overhead, we can consider moving the
restriction. But, for now, simply disallowing the corner case should be
good enough as a hot fix.
Link: https://lkml.kernel.org/r/20260214214124.87689-1-sj@kernel.org
Fixes: d8f867fa0825 ("mm/damon: add damon_ctx->min_sz_region")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Quanmin Yan <yanquanmin1@huawei.com>
Cc: <stable@vger.kernel.org> [6.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
LUO keeps track of successful retrieve attempts on a LUO file. It does so
to avoid multiple retrievals of the same file. Multiple retrievals cause
problems because once the file is retrieved, the serialized data
structures are likely freed and the file is likely in a very different
state from what the code expects.
The retrieve boolean in struct luo_file keeps track of this, and is passed
to the finish callback so it knows what work was already done and what it
has left to do.
All this works well when retrieve succeeds. When it fails,
luo_retrieve_file() returns the error immediately, without ever storing
anywhere that a retrieve was attempted or what its error code was. This
results in an errored LIVEUPDATE_SESSION_RETRIEVE_FD ioctl to userspace,
but nothing prevents it from trying this again.
The retry is problematic for much of the same reasons listed above. The
file is likely in a very different state than what the retrieve logic
normally expects, and it might even have freed some serialization data
structures. Attempting to access them or free them again is going to
break things.
For example, if memfd managed to restore 8 of its 10 folios, but fails on
the 9th, a subsequent retrieve attempt will try to call
kho_restore_folio() on the first folio again, and that will fail with a
warning since it is an invalid operation.
Apart from the retry, finish() also breaks. Since on failure the
retrieved bool in luo_file is never touched, the finish() call on session
close will tell the file handler that retrieve was never attempted, and it
will try to access or free the data structures that might not exist, much
in the same way as the retry attempt.
There is no sane way of attempting the retrieve again. Remember the error
retrieve returned and directly return it on a retry. Also pass this
status code to finish() so it can make the right decision on the work it
needs to do.
This is done by changing the bool to an integer. A value of 0 means
retrieve was never attempted, a positive value means it succeeded, and a
negative value means it failed and the error code is the value.
Link: https://lkml.kernel.org/r/20260216132221.987987-1-pratyush@kernel.org
Fixes: 7c722a7f44e0 ("liveupdate: luo_file: implement file systems callbacks")
Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
file_thp_enabled() incorrectly allows THP for files on anonymous inodes
(e.g. guest_memfd and secretmem). These files are created via
alloc_file_pseudo(), which does not call get_write_access() and leaves
inode->i_writecount at 0. Combined with S_ISREG(inode->i_mode) being
true, they appear as read-only regular files when
CONFIG_READ_ONLY_THP_FOR_FS is enabled, making them eligible for THP
collapse.
Anonymous inodes can never pass the inode_is_open_for_write() check
since their i_writecount is never incremented through the normal VFS
open path. The right thing to do is to exclude them from THP eligibility
altogether, since CONFIG_READ_ONLY_THP_FOR_FS was designed for real
filesystem files (e.g. shared libraries), not for pseudo-filesystem
inodes.
For guest_memfd, this allows khugepaged and MADV_COLLAPSE to create
large folios in the page cache via the collapse path, but the
guest_memfd fault handler does not support large folios. This triggers
WARN_ON_ONCE(folio_test_large(folio)) in kvm_gmem_fault_user_mapping().
For secretmem, collapse_file() tries to copy page contents through the
direct map, but secretmem pages are removed from the direct map. This
can result in a kernel crash:
BUG: unable to handle page fault for address: ffff88810284d000
RIP: 0010:memcpy_orig+0x16/0x130
Call Trace:
collapse_file
hpage_collapse_scan_file
madvise_collapse
Secretmem is not affected by the crash on upstream as the memory failure
recovery handles the failed copy gracefully, but it still triggers
confusing false memory failure reports:
Memory failure: 0x106d96f: recovery action for clean unevictable
LRU page: Recovered
Check IS_ANON_FILE(inode) in file_thp_enabled() to deny THP for all
anonymous inode files.
Link: https://syzkaller.appspot.com/bug?extid=33a04338019ac7e43a44
Link: https://lore.kernel.org/linux-mm/CAEvNRgHegcz3ro35ixkDw39ES8=U6rs6S7iP0gkR9enr7HoGtA@mail.gmail.com
Link: https://lkml.kernel.org/r/20260214001535.435626-1-kartikey406@gmail.com
Fixes: 7fbb5e188248 ("mm: remove VM_EXEC requirement for THP eligibility")
Signed-off-by: Deepanshu Kartikey <Kartikey406@gmail.com>
Reported-by: syzbot+33a04338019ac7e43a44@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=33a04338019ac7e43a44
Tested-by: syzbot+33a04338019ac7e43a44@syzkaller.appspotmail.com
Tested-by: Lance Yang <lance.yang@linux.dev>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Barry Song <baohua@kernel.org>
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Tested-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Fangrui Song <i@maskray.me>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
KFENCE does not currently support KASAN hardware tags. As a result, the
two features are incompatible when enabled simultaneously.
Given that MTE provides deterministic protection and KFENCE is a
sampling-based debugging tool, prioritize the stronger hardware
protections. Disable KFENCE initialization and free the pre-allocated
pool if KASAN hardware tags are detected to ensure the system maintains
the security guarantees provided by MTE.
Link: https://lkml.kernel.org/r/20260213095410.1862978-1-glider@google.com
Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure")
Signed-off-by: Alexander Potapenko <glider@google.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ernesto Martinez Garcia <ernesto.martinezgarcia@tugraz.at>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Kees Cook <kees@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Conversion performed via this Coccinelle script:
// SPDX-License-Identifier: GPL-2.0-only
// Options: --include-headers-for-types --all-includes --include-headers --keep-comments
virtual patch
@gfp depends on patch && !(file in "tools") && !(file in "samples")@
identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
kzalloc_obj,kzalloc_objs,kzalloc_flex,
kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
@@
ALLOC(...
- , GFP_KERNEL
)
$ make coccicheck MODE=patch COCCI=gfp.cocci
Build and boot tested x86_64 with Fedora 42's GCC and Clang:
Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This converts some of the visually simpler cases that have been split
over multiple lines. I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.
Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script. I probably had made it a bit _too_ trivial.
So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.
The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.
As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull kmalloc_obj conversion from Kees Cook:
"This does the tree-wide conversion to kmalloc_obj() and friends using
coccinelle, with a subsequent small manual cleanup of whitespace
alignment that coccinelle does not handle.
This uncovered a clang bug in __builtin_counted_by_ref(), so the
conversion is preceded by disabling that for current versions of
clang. The imminent clang 22.1 release has the fix.
I've done allmodconfig build tests for x86_64, arm64, i386, and arm. I
did defconfig builds for alpha, m68k, mips, parisc, powerpc, riscv,
s390, sparc, sh, arc, csky, xtensa, hexagon, and openrisc"
* tag 'kmalloc_obj-treewide-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
kmalloc_obj: Clean up after treewide replacements
treewide: Replace kmalloc with kmalloc_obj for non-scalar types
compiler_types: Disable __builtin_counted_by_ref for Clang
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock
Pull memblock fix from Mike Rapoport:
"Fix detection of NUMA node for CXL windows
phys_to_target_node() may assign a CXL Fixed Memory Window to the
wrong NUMA node when a CXL node resides in the gap of discontinuous
System RAM node.
Fix this by checking both numa_meminfo and numa_reserved_meminfo,
preferring the reserved NID when the address appears in both"
* tag 'fixes-2026-02-21' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
mm: numa_memblks: Identify the accurate NUMA ID of CFMW
|
|
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:
- "mm/vmscan: fix demotion targets checks in reclaim/demotion" fixes a
couple of issues in the demotion code - pages were failed demotion
and were finding themselves demoted into disallowed nodes (Bing Jiao)
- "Remove XA_ZERO from error recovery of dup_mmap()" fixes a rare
mapledtree race and performs a number of cleanups (Liam Howlett)
- "mm: add bitmap VMA flag helpers and convert all mmap_prepare to use
them" implements a lot of cleanups following on from the conversion
of the VMA flags into a bitmap (Lorenzo Stoakes)
- "support batch checking of references and unmapping for large folios"
implements batching to greatly improve the performance of reclaiming
clean file-backed large folios (Baolin Wang)
- "selftests/mm: add memory failure selftests" does as claimed (Miaohe
Lin)
* tag 'mm-stable-2026-02-18-19-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (36 commits)
mm/page_alloc: clear page->private in free_pages_prepare()
selftests/mm: add memory failure dirty pagecache test
selftests/mm: add memory failure clean pagecache test
selftests/mm: add memory failure anonymous page test
mm: rmap: support batched unmapping for file large folios
arm64: mm: implement the architecture-specific clear_flush_young_ptes()
arm64: mm: support batch clearing of the young flag for large folios
arm64: mm: factor out the address and ptep alignment into a new helper
mm: rmap: support batched checks of the references for large folios
tools/testing/vma: add VMA userland tests for VMA flag functions
tools/testing/vma: separate out vma_internal.h into logical headers
tools/testing/vma: separate VMA userland tests into separate files
mm: make vm_area_desc utilise vma_flags_t only
mm: update all remaining mmap_prepare users to use vma_flags_t
mm: update shmem_[kernel]_file_*() functions to use vma_flags_t
mm: update secretmem to use VMA flags on mmap_prepare
mm: update hugetlbfs to use VMA flags on mmap_prepare
mm: add basic VMA flag operation helper functions
tools: bitmap: add missing bitmap_[subset(), andnot()]
mm: add mk_vma_flags() bitmap flag macro helper
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull more slab updates from Vlastimil Babka:
- Two stable fixes for kmalloc_nolock() usage from NMI context (Harry
Yoo)
- Allow kmalloc_nolock() allocations to be freed with kfree() and thus
also kfree_rcu() and simplify slabobj_ext handling - we no longer
need to track how it was allocated to use the matching freeing
function (Harry Yoo)
* tag 'slab-for-7.0-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm/slab: drop the OBJEXTS_NOSPIN_ALLOC flag from enum objext_flags
mm/slab: allow freeing kmalloc_nolock()'d objects using kfree[_rcu]()
mm/slab: use prandom if !allow_spin
mm/slab: do not access current->mems_allowed_seq if !allow_spin
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock
Pull memblock updates from Mike Rapoport:
- update tools/include/linux/mm.h to fix memblock tests compilation
- drop redundant struct page* parameter from memblock_free_pages() and
get struct page from the pfn
- add underflow detection for size calculation in memtest and warn
about underflow when VM_DEBUG is enabled
* tag 'memblock-v7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
mm/memtest: add underflow detection for size calculation
memblock: drop redundant 'struct page *' argument from memblock_free_pages()
memblock test: include <linux/sizes.h> from tools mm.h stub
|
|
In some physical memory layout designs, the address space of CFMW (CXL
Fixed Memory Window) resides between multiple segments of system memory
belonging to the same NUMA node. In numa_cleanup_meminfo, these multiple
segments of system memory are merged into a larger numa_memblk. When
identifying which NUMA node the CFMW belongs to, it may be incorrectly
assigned to the NUMA node of the merged system memory.
When a CXL RAM region is created in userspace, the memory capacity of
the newly created region is not added to the CFMW-dedicated NUMA node.
Instead, it is accumulated into an existing NUMA node (e.g., NUMA0
containing RAM). This makes it impossible to clearly distinguish
between the two types of memory, which may affect memory-tiering
applications.
Example memory layout:
Physical address space:
0x00000000 - 0x1FFFFFFF System RAM (node0)
0x20000000 - 0x2FFFFFFF CXL CFMW (node2)
0x40000000 - 0x5FFFFFFF System RAM (node0)
0x60000000 - 0x7FFFFFFF System RAM (node1)
After numa_cleanup_meminfo, the two node0 segments are merged into one:
0x00000000 - 0x5FFFFFFF System RAM (node0) // CFMW is inside the range
0x60000000 - 0x7FFFFFFF System RAM (node1)
So the CFMW (0x20000000-0x2FFFFFFF) will be incorrectly assigned to node0.
To address this scenario, accurately identifying the correct NUMA node
can be achieved by checking whether the region belongs to both
numa_meminfo and numa_reserved_meminfo.
While this issue is only observed in a QEMU configuration, and no known
end users are impacted by this problem, it is likely that some firmware
implementation is leaving memory map holes in a CXL Fixed Memory Window.
CXL hotplug depends on mapping free window capacity, and it seems to be
only a coincidence to have not hit this problem yet.
Fixes: 779dd20cfb56 ("cxl/region: Add region creation support")
Signed-off-by: Cui Chao <cuichao1753@phytium.com.cn>
Cc: stable@vger.kernel.org
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Gregory Price <gourry@gourry.net>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20260213060347.2389818-2-cuichao1753@phytium.com.cn
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM fixes from Andrew Morton:
"Three MM hotfixes, all three are cc:stable"
* tag 'mm-hotfixes-stable-2026-02-13-07-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
procfs: fix possible double mmput() in do_procmap_query()
mm/page_alloc: skip debug_check_no_{obj,locks}_freed with FPI_TRYLOCK
mm/hugetlb: restore failed global reservations to subpool
|
|
Pull KVM updates from Paolo Bonzini:
"Loongarch:
- Add more CPUCFG mask bits
- Improve feature detection
- Add lazy load support for FPU and binary translation (LBT) register
state
- Fix return value for memory reads from and writes to in-kernel
devices
- Add support for detecting preemption from within a guest
- Add KVM steal time test case to tools/selftests
ARM:
- Add support for FEAT_IDST, allowing ID registers that are not
implemented to be reported as a normal trap rather than as an UNDEF
exception
- Add sanitisation of the VTCR_EL2 register, fixing a number of
UXN/PXN/XN bugs in the process
- Full handling of RESx bits, instead of only RES0, and resulting in
SCTLR_EL2 being added to the list of sanitised registers
- More pKVM fixes for features that are not supposed to be exposed to
guests
- Make sure that MTE being disabled on the pKVM host doesn't give it
the ability to attack the hypervisor
- Allow pKVM's host stage-2 mappings to use the Force Write Back
version of the memory attributes by using the "pass-through'
encoding
- Fix trapping of ICC_DIR_EL1 on GICv5 hosts emulating GICv3 for the
guest
- Preliminary work for guest GICv5 support
- A bunch of debugfs fixes, removing pointless custom iterators
stored in guest data structures
- A small set of FPSIMD cleanups
- Selftest fixes addressing the incorrect alignment of page
allocation
- Other assorted low-impact fixes and spelling fixes
RISC-V:
- Fixes for issues discoverd by KVM API fuzzing in
kvm_riscv_aia_imsic_has_attr(), kvm_riscv_aia_imsic_rw_attr(), and
kvm_riscv_vcpu_aia_imsic_update()
- Allow Zalasr, Zilsd and Zclsd extensions for Guest/VM
- Transparent huge page support for hypervisor page tables
- Adjust the number of available guest irq files based on MMIO
register sizes found in the device tree or the ACPI tables
- Add RISC-V specific paging modes to KVM selftests
- Detect paging mode at runtime for selftests
s390:
- Performance improvement for vSIE (aka nested virtualization)
- Completely new memory management. s390 was a special snowflake that
enlisted help from the architecture's page table management to
build hypervisor page tables, in particular enabling sharing the
last level of page tables. This however was a lot of code (~3K
lines) in order to support KVM, and also blocked several features.
The biggest advantages is that the page size of userspace is
completely independent of the page size used by the guest:
userspace can mix normal pages, THPs and hugetlbfs as it sees fit,
and in fact transparent hugepages were not possible before. It's
also now possible to have nested guests and guests with huge pages
running on the same host
- Maintainership change for s390 vfio-pci
- Small quality of life improvement for protected guests
x86:
- Add support for giving the guest full ownership of PMU hardware
(contexted switched around the fastpath run loop) and allowing
direct access to data MSRs and PMCs (restricted by the vPMU model).
KVM still intercepts access to control registers, e.g. to enforce
event filtering and to prevent the guest from profiling sensitive
host state. This is more accurate, since it has no risk of
contention and thus dropped events, and also has significantly less
overhead.
For more information, see the commit message for merge commit
bf2c3138ae36 ("Merge tag 'kvm-x86-pmu-6.20' ...")
- Disallow changing the virtual CPU model if L2 is active, for all
the same reasons KVM disallows change the model after the first
KVM_RUN
- Fix a bug where KVM would incorrectly reject host accesses to PV
MSRs when running with KVM_CAP_ENFORCE_PV_FEATURE_CPUID enabled,
even if those were advertised as supported to userspace,
- Fix a bug with protected guest state (SEV-ES/SNP and TDX) VMs,
where KVM would attempt to read CR3 configuring an async #PF entry
- Fail the build if EXPORT_SYMBOL_GPL or EXPORT_SYMBOL is used in KVM
(for x86 only) to enforce usage of EXPORT_SYMBOL_FOR_KVM_INTERNAL.
Only a few exports that are intended for external usage, and those
are allowed explicitly
- When checking nested events after a vCPU is unblocked, ignore
-EBUSY instead of WARNing. Userspace can sometimes put the vCPU
into what should be an impossible state, and spurious exit to
userspace on -EBUSY does not really do anything to solve the issue
- Also throw in the towel and drop the WARN on INIT/SIPI being
blocked when vCPU is in Wait-For-SIPI, which also resulted in
playing whack-a-mole with syzkaller stuffing architecturally
impossible states into KVM
- Add support for new Intel instructions that don't require anything
beyond enumerating feature flags to userspace
- Grab SRCU when reading PDPTRs in KVM_GET_SREGS2
- Add WARNs to guard against modifying KVM's CPU caps outside of the
intended setup flow, as nested VMX in particular is sensitive to
unexpected changes in KVM's golden configuration
- Add a quirk to allow userspace to opt-in to actually suppress EOI
broadcasts when the suppression feature is enabled by the guest
(currently limited to split IRQCHIP, i.e. userspace I/O APIC).
Sadly, simply fixing KVM to honor Suppress EOI Broadcasts isn't an
option as some userspaces have come to rely on KVM's buggy behavior
(KVM advertises Supress EOI Broadcast irrespective of whether or
not userspace I/O APIC supports Directed EOIs)
- Clean up KVM's handling of marking mapped vCPU pages dirty
- Drop a pile of *ancient* sanity checks hidden behind in KVM's
unused ASSERT() macro, most of which could be trivially triggered
by the guest and/or user, and all of which were useless
- Fold "struct dest_map" into its sole user, "struct rtc_status", to
make it more obvious what the weird parameter is used for, and to
allow fropping these RTC shenanigans if CONFIG_KVM_IOAPIC=n
- Bury all of ioapic.h, i8254.h and related ioctls (including
KVM_CREATE_IRQCHIP) behind CONFIG_KVM_IOAPIC=y
- Add a regression test for recent APICv update fixes
- Handle "hardware APIC ISR", a.k.a. SVI, updates in
kvm_apic_update_apicv() to consolidate the updates, and to
co-locate SVI updates with the updates for KVM's own cache of ISR
information
- Drop a dead function declaration
- Minor cleanups
x86 (Intel):
- Rework KVM's handling of VMCS updates while L2 is active to
temporarily switch to vmcs01 instead of deferring the update until
the next nested VM-Exit.
The deferred updates approach directly contributed to several bugs,
was proving to be a maintenance burden due to the difficulty in
auditing the correctness of deferred updates, and was polluting
"struct nested_vmx" with a growing pile of booleans
- Fix an SGX bug where KVM would incorrectly try to handle EPCM page
faults, and instead always reflect them into the guest. Since KVM
doesn't shadow EPCM entries, EPCM violations cannot be due to KVM
interference and can't be resolved by KVM
- Fix a bug where KVM would register its posted interrupt wakeup
handler even if loading kvm-intel.ko ultimately failed
- Disallow access to vmcb12 fields that aren't fully supported,
mostly to avoid weirdness and complexity for FRED and other
features, where KVM wants enable VMCS shadowing for fields that
conditionally exist
- Print out the "bad" offsets and values if kvm-intel.ko refuses to
load (or refuses to online a CPU) due to a VMCS config mismatch
x86 (AMD):
- Drop a user-triggerable WARN on nested_svm_load_cr3() failure
- Add support for virtualizing ERAPS. Note, correct virtualization of
ERAPS relies on an upcoming, publicly announced change in the APM
to reduce the set of conditions where hardware (i.e. KVM) *must*
flush the RAP
- Ignore nSVM intercepts for instructions that are not supported
according to L1's virtual CPU model
- Add support for expedited writes to the fast MMIO bus, a la VMX's
fastpath for EPT Misconfig
- Don't set GIF when clearing EFER.SVME, as GIF exists independently
of SVM, and allow userspace to restore nested state with GIF=0
- Treat exit_code as an unsigned 64-bit value through all of KVM
- Add support for fetching SNP certificates from userspace
- Fix a bug where KVM would use vmcb02 instead of vmcb01 when
emulating VMLOAD or VMSAVE on behalf of L2
- Misc fixes and cleanups
x86 selftests:
- Add a regression test for TPR<=>CR8 synchronization and IRQ masking
- Overhaul selftest's MMU infrastructure to genericize stage-2 MMU
support, and extend x86's infrastructure to support EPT and NPT
(for L2 guests)
- Extend several nested VMX tests to also cover nested SVM
- Add a selftest for nested VMLOAD/VMSAVE
- Rework the nested dirty log test, originally added as a regression
test for PML where KVM logged L2 GPAs instead of L1 GPAs, to
improve test coverage and to hopefully make the test easier to
understand and maintain
guest_memfd:
- Remove kvm_gmem_populate()'s preparation tracking and half-baked
hugepage handling. SEV/SNP was the only user of the tracking and it
can do it via the RMP
- Retroactively document and enforce (for SNP) that
KVM_SEV_SNP_LAUNCH_UPDATE and KVM_TDX_INIT_MEM_REGION require the
source page to be 4KiB aligned, to avoid non-trivial complexity for
something that no known VMM seems to be doing and to avoid an API
special case for in-place conversion, which simply can't support
unaligned sources
- When populating guest_memfd memory, GUP the source page in common
code and pass the refcounted page to the vendor callback, instead
of letting vendor code do the heavy lifting. Doing so avoids a
looming deadlock bug with in-place due an AB-BA conflict betwee
mmap_lock and guest_memfd's filemap invalidate lock
Generic:
- Fix a bug where KVM would ignore the vCPU's selected address space
when creating a vCPU-specific mapping of guest memory. Actually
this bug could not be hit even on x86, the only architecture with
multiple address spaces, but it's a bug nevertheless"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (267 commits)
KVM: s390: Increase permitted SE header size to 1 MiB
MAINTAINERS: Replace backup for s390 vfio-pci
KVM: s390: vsie: Fix race in acquire_gmap_shadow()
KVM: s390: vsie: Fix race in walk_guest_tables()
KVM: s390: Use guest address to mark guest page dirty
irqchip/riscv-imsic: Adjust the number of available guest irq files
RISC-V: KVM: Transparent huge page support
RISC-V: KVM: selftests: Add Zalasr extensions to get-reg-list test
RISC-V: KVM: Allow Zalasr extensions for Guest/VM
KVM: riscv: selftests: Add riscv vm satp modes
KVM: riscv: selftests: add Zilsd and Zclsd extension to get-reg-list test
riscv: KVM: allow Zilsd and Zclsd extensions for Guest/VM
RISC-V: KVM: Skip IMSIC update if vCPU IMSIC state is not initialized
RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_rw_attr()
RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_has_attr()
RISC-V: KVM: Remove unnecessary 'ret' assignment
KVM: s390: Add explicit padding to struct kvm_s390_keyop
KVM: LoongArch: selftests: Add steal time test case
LoongArch: KVM: Add paravirt vcpu_is_preempted() support in guest side
LoongArch: KVM: Add paravirt preempt feature in hypervisor side
...
|
|
Several subsystems (slub, shmem, ttm, etc.) use page->private but don't
clear it before freeing pages. When these pages are later allocated as
high-order pages and split via split_page(), tail pages retain stale
page->private values.
This causes a use-after-free in the swap subsystem. The swap code uses
page->private to track swap count continuations, assuming freshly
allocated pages have page->private == 0. When stale values are present,
swap_count_continued() incorrectly assumes the continuation list is valid
and iterates over uninitialized page->lru containing LIST_POISON values,
causing a crash:
KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107]
RIP: 0010:__do_sys_swapoff+0x1151/0x1860
Fix this by clearing page->private in free_pages_prepare(), ensuring all
freed pages have clean state regardless of previous use.
Link: https://lkml.kernel.org/r/20260207173615.146159-1-mikhail.v.gavrilov@gmail.com
Fixes: 3b8000ae185c ("mm/vmalloc: huge vmalloc backing pages should be split rather than compound")
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Suggested-by: Zi Yan <ziy@nvidia.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Similar to folio_referenced_one(), we can apply batched unmapping for file
large folios to optimize the performance of file folios reclamation.
Barry previously implemented batched unmapping for lazyfree anonymous
large folios[1] and did not further optimize anonymous large folios or
file-backed large folios at that stage. As for file-backed large folios,
the batched unmapping support is relatively straightforward, as we only
need to clear the consecutive (present) PTE entries for file-backed large
folios.
Note that it's not ready to support batched unmapping for uffd case, so
let's still fallback to per-page unmapping for the uffd case.
Performance testing:
Allocate 10G clean file-backed folios by mmap() in a memory cgroup, and
try to reclaim 8G file-backed folios via the memory.reclaim interface. I
can observe 75% performance improvement on my Arm64 32-core server (and
50%+ improvement on my X86 machine) with this patch.
W/o patch:
real 0m1.018s
user 0m0.000s
sys 0m1.018s
W/ patch:
real 0m0.249s
user 0m0.000s
sys 0m0.249s
[1] https://lore.kernel.org/all/20250214093015.51024-4-21cnbao@gmail.com/T/#u
Link: https://lkml.kernel.org/r/b53a16f67c93a3fe65e78092069ad135edf00eff.1770645603.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: Barry Song <baohua@kernel.org>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series "support batch checking of references and unmapping for large
folios", v6.
Currently, folio_referenced_one() always checks the young flag for each
PTE sequentially, which is inefficient for large folios. This
inefficiency is especially noticeable when reclaiming clean file-backed
large folios, where folio_referenced() is observed as a significant
performance hotspot.
Moreover, on Arm architecture, which supports contiguous PTEs, there is
already an optimization to clear the young flags for PTEs within a
contiguous range. However, this is not sufficient. We can extend this to
perform batched operations for the entire large folio (which might exceed
the contiguous range: CONT_PTE_SIZE).
Similar to folio_referenced_one(), we can also apply batched unmapping for
large file folios to optimize the performance of file folio reclamation.
By supporting batched checking of the young flags, flushing TLB entries,
and unmapping, I can observed a significant performance improvements in my
performance tests for file folios reclamation. Please check the
performance data in the commit message of each patch.
This patch (of 5):
Currently, folio_referenced_one() always checks the young flag for each
PTE sequentially, which is inefficient for large folios. This
inefficiency is especially noticeable when reclaiming clean file-backed
large folios, where folio_referenced() is observed as a significant
performance hotspot.
Moreover, on Arm64 architecture, which supports contiguous PTEs, there is
already an optimization to clear the young flags for PTEs within a
contiguous range. However, this is not sufficient. We can extend this to
perform batched operations for the entire large folio (which might exceed
the contiguous range: CONT_PTE_SIZE).
Introduce a new API: clear_flush_young_ptes() to facilitate batched
checking of the young flags and flushing TLB entries, thereby improving
performance during large folio reclamation. And it will be overridden by
the architecture that implements a more efficient batch operation in the
following patches.
While we are at it, rename ptep_clear_flush_young_notify() to
clear_flush_young_ptes_notify() to indicate that this is a batch
operation.
Link: https://lkml.kernel.org/r/cover.1770645603.git.baolin.wang@linux.alibaba.com
Link: https://lkml.kernel.org/r/12132694536834262062d1fb304f8f8a064b6750.1770645603.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Now we have eliminated all uses of vm_area_desc->vm_flags, eliminate this
field, and have mmap_prepare users utilise the vma_flags_t
vm_area_desc->vma_flags field only.
As part of this change we alter is_shared_maywrite() to accept a
vma_flags_t parameter, and introduce is_shared_maywrite_vm_flags() for use
with legacy vm_flags_t flags.
We also update struct mmap_state to add a union between vma_flags and
vm_flags temporarily until the mmap logic is also converted to using
vma_flags_t.
Also update the VMA userland tests to reflect this change.
Link: https://lkml.kernel.org/r/fd2a2938b246b4505321954062b1caba7acfc77a.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
We will be shortly removing the vm_flags_t field from vm_area_desc so we
need to update all mmap_prepare users to only use the dessc->vma_flags
field.
This patch achieves that and makes all ancillary changes required to make
this possible.
This lays the groundwork for future work to eliminate the use of
vm_flags_t in vm_area_desc altogether and more broadly throughout the
kernel.
While we're here, we take the opportunity to replace VM_REMAP_FLAGS with
VMA_REMAP_FLAGS, the vma_flags_t equivalent.
No functional changes intended.
Link: https://lkml.kernel.org/r/fb1f55323799f09fe6a36865b31550c9ec67c225.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Damien Le Moal <dlemoal@kernel.org> [zonefs]
Acked-by: "Darrick J. Wong" <djwong@kernel.org>
Acked-by: Pedro Falcato <pfalcato@suse.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In order to be able to use only vma_flags_t in vm_area_desc we must adjust
shmem file setup functions to operate in terms of vma_flags_t rather than
vm_flags_t.
This patch makes this change and updates all callers to use the new
functions.
No functional changes intended.
[akpm@linux-foundation.org: comment fixes, per Baolin]
Link: https://lkml.kernel.org/r/736febd280eb484d79cef5cf55b8a6f79ad832d2.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
This patch updates secretmem to use the new vma_flags_t type which will
soon supersede vm_flags_t altogether.
In order to make this change we also have to update mlock_future_ok(), we
replace the vm_flags_t parameter with a simple boolean is_vma_locked one,
which also simplifies the invocation here.
This is laying the groundwork for eliminating the vm_flags_t in
vm_area_desc and more broadly throughout the kernel.
No functional changes intended.
[lorenzo.stoakes@oracle.com: fix check_brk_limits(), per Chris]
Link: https://lkml.kernel.org/r/3aab9ab1-74b4-405e-9efb-08fc2500c06e@lucifer.local
Link: https://lkml.kernel.org/r/a243a09b0a5d0581e963d696de1735f61f5b2075.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In order to update all mmap_prepare users to utilising the new VMA flags
type vma_flags_t and associated helper functions, we start by updating
hugetlbfs which has a lot of additional logic that requires updating to
make this change.
This is laying the groundwork for eliminating the vm_flags_t from struct
vm_area_desc and using vma_flags_t only, which further lays the ground for
removing the deprecated vm_flags_t type altogether.
No functional changes intended.
Link: https://lkml.kernel.org/r/9226bec80c9aa3447cc2b83354f733841dba8a50.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
In order to stay consistent between functions which manipulate a
vm_flags_t argument of the form of vma_flags_...() and those which
manipulate a VMA (in this case the flags field of a VMA), rename
vma_flag_[test/set]_atomic() to vma_[test/set]_atomic_flag().
This lays the groundwork for adding VMA flag manipulation functions in a
subsequent commit.
Link: https://lkml.kernel.org/r/033dcf12e819dee5064582bced9b12ea346d1607.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Pass through the unmap_desc to free_pgtables() because it almost has
everything necessary and is already on the stack.
Updates testing code as necessary.
No functional changes intended.
[Liam.Howlett@oracle.com: fix up unmap desc use on exit_mmap()]
Link: https://lkml.kernel.org/r/20260210214214.364856-1-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20260121164946.2093480-12-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
There is no need to open code the vms_clear_ptes() now that unmap_desc
struct is used.
Link: https://lkml.kernel.org/r/20260121164946.2093480-11-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Convert vms_clear_ptes() to use unmap_desc to call unmap_vmas() instead of
the large argument list. The UNMAP_STATE() cannot be used because the vma
iterator in the vms does not point to the correct maple state
(mas_detach), and the tree_end will be set incorrectly. Setting up the
arguments manually avoids setting the struct up incorrectly and doing
extra work to get the correct pagetable range.
exit_mmap() also calls unmap_vmas() with many arguments. Using the
unmap_all_init() function to set the unmap descriptor for all vmas makes
this a bit easier to read.
Update to the vma test code is necessary to ensure testing continues to
function.
No functional changes intended.
Link: https://lkml.kernel.org/r/20260121164946.2093480-10-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The unmap_region code uses a number of arguments that could use better
documentation. With the addition of a descriptor for unmap (called
unmap_desc), the arguments can be more self-documenting and increase the
descriptions within the declaration.
No functional change intended
Link: https://lkml.kernel.org/r/20260121164946.2093480-9-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
When the dup_mmap() fails during the vma duplication or setup, don't write
the XA_ZERO entry in the vma tree. Instead, destroy the tree and free the
new resources, leaving an empty vma tree.
Using XA_ZERO introduced races where the vma could be found between
dup_mmap() dropping all locks and exit_mmap() taking the locks. The race
can occur because the mm can be reached through the other trees via
successfully copied vmas and other methods such as the swapoff code.
XA_ZERO was marking the location to stop vma removal and pagetable
freeing. The newly created arguments to the unmap_vmas() and
free_pgtables() serve this function.
Replacing the XA_ZERO entry use with the new argument list also means the
checks for xa_is_zero() are no longer necessary so these are also removed.
Note that dup_mmap() now cleans up when ALL vmas are successfully copied,
but the dup_mmap() fails to completely set up some other aspect of the
duplication.
Link: https://lkml.kernel.org/r/20260121164946.2093480-8-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The unmap_region() calls need to pass through the page table limit for a
future patch.
No functional changes intended.
Link: https://lkml.kernel.org/r/20260121164946.2093480-7-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
The ceiling and tree search limit need to be different arguments for the
future change in the failed fork attempt. The ceiling and floor variables
are not very descriptive, so change them to pg_start/pg_end.
Adding a new variable for the vma_end to the function as it will differ
from the pg_end in the later patches in the series.
Add a kernel doc about the free_pgtables() function.
Test code also updated.
No functional changes intended.
Link: https://lkml.kernel.org/r/20260121164946.2093480-6-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Add a limit to the vma search instead of using the start and end of the
one passed in.
No functional changes intended.
Link: https://lkml.kernel.org/r/20260121164946.2093480-5-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Create the new function tear_down_vmas() to remove a range of vmas.
exit_mmap() will be removing all the vmas.
This is necessary for future patches.
No functional changes intended.
Link: https://lkml.kernel.org/r/20260121164946.2093480-4-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Move the trace point later in the function so that it is not skipped in
the event of a failed fork.
Link: https://lkml.kernel.org/r/20260121164946.2093480-3-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Acked-by: Chris Li <chrisl@kernel.org>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Patch series " Remove XA_ZERO from error recovery of dup_mmap()", v3.
It is possible that the dup_mmap() call fails on allocating or setting up
a vma after the maple tree of the oldmm is copied. Today, that failure
point is marked by inserting an XA_ZERO entry over the failure point so
that the exact location does not need to be communicated through to
exit_mmap().
However, a race exists in the tear down process because the dup_mmap()
drops the mmap lock before exit_mmap() can remove the partially set up vma
tree. This means that other tasks may get to the mm tree and find the
invalid vma pointer (since it's an XA_ZERO entry), even though the mm is
marked as MMF_OOM_SKIP and MMF_UNSTABLE.
To remove the race fully, the tree must be cleaned up before dropping the
lock. This is accomplished by extracting the vma cleanup in exit_mmap()
and changing the required functions to pass through the vma search limit.
Any other tree modifications would require extra cycles which should be
spent on freeing memory.
This does run the risk of increasing the possibility of finding no vmas
(which is already possible!) in code that isn't careful.
The final four patches are to address the excessive argument lists being
passed between the functions. Using the struct unmap_desc also allows
some special-case code to be removed in favour of the struct setup
differences.
This patch (of 11):
pgtables.h defines a fallback for ceiling and floor of the page tables
within the CONFIG_MMU section. Moving the definitions to outside the
CONFIG_MMU allows for using them in generic code.
[akpm@linux-foundation.org: remove stray newline, per SeongJae]
Link: https://lkml.kernel.org/r/20260121164946.2093480-1-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20260121164946.2093480-2-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Suggested-by: SeongJae Park <sj@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
