mtk_mfg_attach_dev() reads prev_o on the first iteration of its loop,
in "if (prev_o && prev_o->freq == o->freq)", before prev_o is assigned
at the end of the loop body. On that first iteration, evaluating prev_o
reads an indeterminate value. If it is non-NULL, the condition
dereferences a stale or invalid pointer, potentially faulting or
incorrectly skipping the first OPP.
Initialize prev_o to NULL. This matches the intent as well: there is no
previous OPP to compare against on the first iteration.
Found with Clang's -Wconditional-uninitialized.
Fixes: f08e7a4e8d ("pmdomain: mediatek: Add support for MFlexGraphics")
Assisted-by: Claude:claude-fable-5
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Reviewed-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulfh@kernel.org>
Add a minimal Module Controller driver for the R-Car X5H (R8A78000) SoC.
For now this just supports the always-on power domains, and dummy module
clocks and resets for the serial console (which is enabled by the boot
loader).
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Ulf Hansson <ulfh@kernel.org>
All users have been migrated to `ModuleMetadata::THIS_MODULE` const or
`this_module::<LocalModule>()` helper. The `static THIS_MODULE`
generated by the `module!` macro is no longer referenced anywhere,
so remove it to avoid having two sources of the same `ThisModule`
pointer.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-9-7e71776f9dbe@linux.dev
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Replace the `THIS_MODULE` static reference in the binder fops with
`this_module::<LocalModule>()`, consistent with the move of
`THIS_MODULE` into the `ModuleMetadata` trait.
Assisted-by: opencode:glm-5.2
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-8-7e71776f9dbe@linux.dev
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Replace the `THIS_MODULE` static reference in the `configfs_attrs!`
macro with `this_module::<LocalModule>()`, and update
rnull to import `LocalModule` instead of `THIS_MODULE`, consistent
with the move of `THIS_MODULE` into the `ModuleMetadata` trait.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-7-7e71776f9dbe@linux.dev
[ Rebased to avoid the imports cleanup patch. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Set the miscdevice fops owner field from the driver module pointer
via the `this_module::<T::OwnerModule>()` helper, instead of
defaulting to null.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-6-7e71776f9dbe@linux.dev
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Change `create_fops()` to accept an owner module pointer instead of
hardcoding `null_mut()`, ensuring the kernel correctly tracks the
module owning the DRM device's file operations.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-5-7e71776f9dbe@linux.dev
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Auto-add `type OwnerModule: ::kernel::ModuleMetadata;` as a required
associated type on the trait side if not already defined, and
auto-insert `type OwnerModule = crate::LocalModule;` on the impl side
if not explicitly provided, eliminating the need to manually declare
and implement `OwnerModule` in every vtable trait and impl.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Suggested-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/all/DIMMWHUOLPSH.13JFRHDKDQJGO@garyguo.net
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-4-7e71776f9dbe@linux.dev
[ Fixed `rusttest` by adding a dummy `LocalModule`. Removed interim
`#[allow(dead_code)]`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Add a `LocalModule` struct with a null-pointer `ModuleMetadata` impl
in the doctest harness, so that `crate::LocalModule` (auto-inserted
by `#[vtable]`) resolves correctly when there is no `module!` macro.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-3-7e71776f9dbe@linux.dev
[ Fixed `clippy::undocumented_unsafe_blocks` lint by wrapping with
a block. Added interim `#[allow(dead_code)]`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Since `const_refs_to_static` has been stable as of the MSRV bump, a
`ThisModule` pointer can now be used in const contexts.
Add a `THIS_MODULE` const to the `ModuleMetadata` trait so that modules
can provide their `ThisModule` pointer in const contexts such as static
`file_operations`.
Add a `this_module()` helper to retrieve the `THIS_MODULE` pointer of a
given module type, and update `__init` to use it instead of the
`THIS_MODULE` static generated by the `module!` macro.
The `static THIS_MODULE` generated by the `module!` macro is retained
for backwards compatibility with existing users and removed in a later
patch once all references have been migrated.
Assisted-by: opencode:glm-5.2
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-2-7e71776f9dbe@linux.dev
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Move `Module`, `InPlaceModule`, `ModuleMetadata` and `ThisModule` from
`lib.rs` into a new `rust/kernel/module.rs`. Re-export them from `lib.rs`
to avoid tree-wide changes.
Switch six bus driver registrations from `module.0` to the public
`ThisModule::as_ptr()` accessor, since the field is no longer visible
outside the new `module` submodule.
No functional change.
Assisted-by: opencode:glm-5.2
Suggested-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/all/DJFIQPLOVO4T.1K8T0VZM30LDA@garyguo.net/
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Petr Pavlu <petr.pavlu@suse.com>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://patch.msgid.link/20260811-fix-fops-owner-v10-1-7e71776f9dbe@linux.dev
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Christoph Hellwig <hch@lst.de> says:
Two fixes for iomap_bio_read_folio_range_sync, a potential kernel
crash when tweaking the device integrity behvavior using sysfs,
and a missing bio_uninit that the Sashiko review of the first fix
found.
* patches from https://patch.msgid.link/20260804124404.737145-1-hch@lst.de:
iomap: iomap_bio_read_folio_range_sync is missing a call to bio_uninit
iomap: don't free integrity payload that doesn't exist
Link: https://patch.msgid.link/20260804124404.737145-1-hch@lst.de
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Which could leak blkg references.
Fixes: c03cea4214 ("iomap: add initial support for writes without buffer heads")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260804124404.737145-3-hch@lst.de
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
fs_bio_integrity_alloc might not allocate a bio integrity payload if PI
verification is disabled on the block device. Check for that case before
calling fs_bio_integrity_free in iomap_bio_read_folio_range_sync to
avoid a NULL pointer dereferences.
Make the branch cover the PI verification as well - while
fs_bio_integrity_verify works without an integrity payload, it requires
one to actually do useful work.
Fixes: 0b10a37052 ("iomap: support T10 protection information")
Cc: stable@vger.kernel.org # v7.1
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Link: https://patch.msgid.link/20260804124404.737145-2-hch@lst.de
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
WARN_ON_ONCE() takes a condition, not a message. The string literals
are always true, so the warnings still trigger but the messages are
never printed.
Use WARN_ONCE(1, ...) instead to print the messages and keep the
once-only behavior.
Found with a Coccinelle script. Clang's -Wstring-conversion also flags
such calls but is not enabled in kernel builds.
Fixes: f0cd988016 ("fs: massage locking helpers")
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Link: https://patch.msgid.link/20260808123802.73687-1-kmehltretter@gmail.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
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Merge tag 'nf-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for net. Still
large batch for this late -rc cycle but at least half of these fixes
in this batch have been cooking for several weeks before:
1) Fix race between ipset list:set GC and swap, use write_lock instead
of rcu read lock section when accessing the index to ensure
interference with ip_set_swap(), from Xiang Mei.
2) Release template conntrack in bridge conntrack when packet is
neither IPv4 nor IPv6 before setting skb as untracked.
From Zhiling Zou.
3) A series of 3 patches for IPVS to address sashiko reports:
Schedulers read destination overload state while connection
accounting and destination configuration can update it concurrently.
The first patch adds a single total connection counter. The second
patch uses it to identify threshold crossings precisely, and updates
OVERLOAD at the crossings and on a threshold edit under dst_lock.
The third patch moves configuration-controlled AVAILABLE to a
separate cflags word, so it cannot clobber OVERLOAD through an
unrelated read-modify-write update.
4) Log invalid packets in TCP and SCTP connection tracking to address
a deadlock when nfnetlink_log is used as logging backend and the
nfnetlink_log conntrack glue support is used. From Zihan Xi.
5) Wait for rcu grace period before releasing pernet state in
nfnetlink_log, otherwise packets can end up access already released
memory, triggering UaF. From Florian Westphal.
6) IPVS needs to reset IP information in control buffer in skbuff when
encapsulating IP packets in ICMP, from Kyle Zeng.
7) IPVS needs to validate ihl field of inner headers in when handling
ICMP response, from Julian Anastasov.
8) Remove a WARN_ON_ONCE reachable from the nf_tables hardware offload
when triggering ENOMEM on GFP_KERNEL allocation,
from Alexey Velichayshiy.
9) Publish reply tuple into the flowtable hashtable first, otherwise
GC might walk over a released tuple when insertion of the original
tuple fail. From Jeremy Jean.
10) Elide counter increment when replacing an ipset element,
from Florian Westphal.
11) Remove unneeded ipset accounting resets on destruction/flush,
from Florian Westphal.
* tag 'nf-26-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: ipset: let destroy callbacks adjust ext mem size
netfilter: ipset: fix list type element drift bug
netfilter: flowtable: publish GC-visible tuple last
netfilter: nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort path
ipvs: revalidate ihl to prevent out-of-bounds access
ipvs: clear IPv4 options after rebasing tunnel ICMP errors
netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state
netfilter: nf_conntrack: defer invalid log until after unlock
ipvs: separate destination availability state
ipvs: properly update the overload flag on dest edit
ipvs: add totalconns for dest
netfilter: bridge: release template ct on non-IP path
netfilter: ipset: fix refcount race between list:set GC and swap
====================
Link: https://patch.msgid.link/20260810190621.894119-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
u32_walk() enumerates both struct tc_u_hnode and struct tc_u_knode
through the walker callback. u32_bind_class() unconditionally casts the
passed fh to tc_u_knode and accesses &n->res, so when fh is actually a
tc_u_hnode, which has no tcf_result member, this results in a
slab-out-of-bounds read of res->classid in tc_cls_bind_class().
The issue can be reproduced with the following commands:
tc qdisc add dev lo root handle 1: hfsc
tc class add dev lo parent 1: classid 1:1 hfsc sc rate 1000kbit
tc filter add dev lo parent 1:1 protocol ip prio 1 u32 match u32 0 0 flowid 1:1
tc class add dev lo parent 1: classid 1:2 hfsc sc rate 2000kbit
Fix this by skipping hash tables via the TC_U32_KEY(handle) check.
Fixes: 07d79fc7d9 ("net_sched: add reverse binding for tc class")
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/1786089038-36366-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Harshitha Ramamurthy says:
====================
gve: Bug fixes for header-split and PTP
This series contains 2 bug fixes for gve.
Patch 1 fixes an issue which causes TX timeouts due to HW detection of
an illegal descriptor. This happens when receiving header-only packets
with header split enabled - this produces an SKB with a zero-length
fragment.
Patch 2 prevents a kernel NULL pointer dereference by stubbing the PTP
adjfine callback.
====================
Link: https://patch.msgid.link/20260807224315.234152-1-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When header split is enabled and a header-only packet is
received such as a pure TCP ACK, GVE will indicate an
RX SKB with a zero-length fragment. If this SKB is then
hairpinned and sent back out, the GVE TX path will emit
a zero-length descriptor. Hardware considers this
an illegal descriptor and stops the queue, causing a
TX timeout and interface reset.
Fix it by not adding the zero-length skb frag.
Cc: stable@vger.kernel.org
Fixes: 5e37d8254e ("gve: Add header split data path")
Suggested-by: Praveen Kaligineedi <pkaligineedi@google.com>
Co-developed-by: Ziwei Xiao <ziweixiao@google.com>
Signed-off-by: Ziwei Xiao <ziweixiao@google.com>
Signed-off-by: Jordan Rhee <jordanrhee@google.com>
Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20260807224315.234152-2-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tcf_action_exec() handles TC_ACT_GOTO_CHAIN by first checking
rcu_access_pointer(a->goto_chain) and then calling
tcf_action_goto_chain_exec(), which does a second, independent
rcu_dereference_bh(a->goto_chain) read and immediately dereferences
chain->filter_chain. A concurrent tcf_action_set_ctrlact() (e.g. the gact
replace path) can clear a->goto_chain between the two reads, so the second
read returns NULL and tcf_action_goto_chain_exec() dereferences NULL.
Fix the race by doing a single rcu_dereference_bh() read of a->goto_chain
in tcf_action_exec(), checking it once for NULL, and passing the resulting
chain pointer into tcf_action_goto_chain_exec(). This turns the split
check/use into a single check/use on one value.
Fixes: ee3bbfe806 ("net/sched: let actions use RCU to access 'goto_chain'")
Reported-by: vega@nebusec.ai
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Davide Caratti <dcaratti@redhat.com>
Link: https://patch.msgid.link/20260809090928.868186-1-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot reported a WARNING in __dev_queue_xmit() triggered via tpacket_snd():
skb_assert_len
WARNING: at include/linux/skbuff.h:2753 skb_assert_len
WARNING: at __dev_queue_xmit+0x21bc/0x4970 net/core/dev.c:4781
Call Trace:
<TASK>
dev_queue_xmit include/linux/netdevice.h:3448 [inline]
packet_xmit+0x243/0x310 net/packet/af_packet.c:276
tpacket_snd net/packet/af_packet.c:2907 [inline]
packet_sendmsg+0x28d6/0x4eb0 net/packet/af_packet.c:3134
When sending 0-byte packets via TPACKET ring buffer on devices with no
hard header (e.g. dev->hard_header_len == 0), tpacket_fill_skb()
populates an skb with skb->len == 0 and returns 0. tpacket_snd() then
forwards this empty skb to packet_xmit(), causing __dev_queue_xmit() to
hit skb_assert_len(skb).
Similar checks exist in packet_snd() via commit dc633700f0
("net/af_packet: check len when min_header_len equals to 0") and in
packet_sendmsg_spkt() via commit 6a341729fb ("af_packet: Don't send
zero-byte data in packet_sendmsg_spkt().").
Return -EINVAL in tpacket_fill_skb() when skb->len is zero to reject
zero-length packets in tpacket_snd().
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+30b93b6845b19cc38581@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6a79e807.01d0871a.3a0d52.00ac.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://patch.msgid.link/20260810150447.1220864-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
__hfsplus_ext_write_extent() writes the cached extent record back into a
B-tree node using fd->entrylength as the length, and fd->entrylength is
derived in __hfs_brec_find() from two on-disk values:
fd->entrylength = len - keylen;
A crafted image can keep both len and keylen valid but make fd->entrylength
negative (keylen > len). __hfsplus_ext_write_extent() doesn't check
fd->entrylength before consuming it, and hfs_bnode_write() takes the length
as u32, so the negative value turns into a huge one. The copy then reads
data past the end of hip->cached_extents, which is only
sizeof(hfsplus_extent_rec) bytes long, and leaks kernel memory into the
image.
Reject an fd->entrylength that does not match sizeof(hfsplus_extent_rec) in
__hfsplus_ext_write_extent(), mirroring the check already performed in
__hfsplus_ext_read_extent().
Link: https://lore.kernel.org/lkml/cbd7003314c530d4f910eacf019ff80adad6687e.camel@dubeyko.com/
Signed-off-by: Jiaming Zhang <r772577952@gmail.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Link: https://lore.kernel.org/r/20260810092422.1691377-1-r772577952@gmail.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
A crafted HFS+ image can contain a corrupted B-tree node. The node
descriptor may contain a record count that does not fit in the node, and
record offsets may be unordered, unaligned, outside the node, or point into
the offset table itself.
Several B-tree helpers consume these on-disk fields before validating them:
hfs_bnode_dump() can walk past the offset table when num_recs is corrupted,
hfs_brec_lenoff() can produce an underflowed length or a record range that
overlaps the offset table. This can make the unlink/writeback path
repeatedly call hfs_bnode_read_u16() with invalid offsets while holding the
HFS+ B-tree lock, producing a flood of "requested invalid offset" messages.
Other writeback workers then block on tree->tree_lock and the system
reports tasks hung in hfsplus_write_inode().
Validate num_recs against the node size before walking the record offset
table. Reject record ranges that are unordered, unaligned, outside the
node, or overlapping the offset table. Reject invalid record indexes before
reading their offset entries, and avoid decrementing an already-zero
leaf_count.
Closes: https://lore.kernel.org/lkml/CANypQFb_2TqKGrztAXj5m0_v+QChxXDnQVeifzV8J25Vuju10Q@mail.gmail.com/
Assisted-by: Codex:gpt-5.5-xhigh
Signed-off-by: Jiaming Zhang <r772577952@gmail.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Tested-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Link: https://lore.kernel.org/r/20260806073358.1184938-1-r772577952@gmail.com
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
read_exports() reports the offending line number when it fails to parse
Module.symvers. The counter is initialized to 1 but never incremented,
so every error blames line 1 regardless of where the bad line is.
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/133e16bb0c7cb916f10bbfb017eba525449ad1d6.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
EXPORT_SYMBOL_FOR_MODULES() puts a symbol in a "module:<names>"
namespace, which the module loader grants access to by matching the
importing module's name against that list.
klp_reloc_needed() only creates a klp reloc for module-owned exports; a
vmlinux export gets a normal reloc. For a vmlinux symbol exported with
EXPORT_SYMBOL_FOR_MODULES(), using a normal reloc results in a modpost
failure in klp-build:
ERROR: modpost: module livepatch-foo uses symbol mpol_shared_policy_lookup from namespace module:kvm, but does not import it.
And the modpost error is correct: even with that error removed, the
patch module would fail to load:
livepatch_foo: module uses symbol (mpol_shared_policy_lookup) from namespace module:kvm, but does not import it.
livepatch_foo: Unknown symbol mpol_shared_policy_lookup (err -22)
Treat it like an unexported symbol by using a klp reloc.
Note this only affects "module:" namespaces. Ordinary namespaced
exports continue to work with normal relocs thanks to copy_import_ns(),
which propagates the patched object's import_ns tags to the patch
module.
Fixes: dd590d4d57 ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://lore.kernel.org/6a6608f4-0a05-4d75-8b7f-edddfac9c5d4@redhat.com
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/fe5a00818e06ec613344d41d5944de054fcd8832.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
klp_reloc_needed() returns true for module exports to support
late-module patching. However, clone_reloc_klp() unconditionally
rejects symbols without a twin (i.e., new references added by the
patch), even when the symbol is a known export from Module.symvers.
Relax the check: allow new references to exported symbols by only
erroring on !twin when there is no export. The export metadata from
Module.symvers provides sufficient context to emit the klp-relocation
without a twin.
For a module export that isn't sufficient on its own though, as the
resulting klp relocation will only be resolved at patch-enable time if
the exporting module is loaded.
If the original (unpatched) module already depends on the exporting
module, the dependency is safe: the module loader ensures the dependency
is satisfied before the patched module can be loaded, so the
klp relocation target will exist.
However, if the patch introduces a reference to a module that the
original doesn't depend on, there is no such guarantee. The exporting
module could be absent or could be unloaded at any time, leading to a
relocation failure or use-after-free.
So also add a build-time check: when a new symbol reference (no twin)
targets a module export, verify that the original module already has at
least one UNDEF symbol resolving to that same exporting module. If not,
error out with a diagnostic message.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/e0d725acb4774747f0e271308b4ca33daae2d5db.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
While cloning a reloc, klp diff calls find_export() to determine whether
the referenced symbol is exported. That decides whether the reference
needs a klp reloc, which object the klp symbol belongs to, and whether
the symbol's data needs to be copied into the patch module.
But find_export() matches purely on symbol name, so a static function or
variable which happens to share its name with an export is mistaken for
a reference to that export:
- klp_reloc_needed() creates a klp reloc pointing at the exporting
module's symbol rather than the local one. For a vmlinux export it
skips the klp reloc altogether, leaving a normal reloc which the
module loader resolves to the vmlinux symbol.
- clone_reloc() treats the symbol as external and clones it without
its data, leaving a dangling reference.
- validate_special_section_klp_reloc() attributes a static branch or
call key to the wrong module, and for a vmlinux export skips the
unsupported-key check entirely.
Exports are always global, so ignore local symbols in find_export().
Fixes: dd590d4d57 ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Acked-by: Song Liu <song@kernel.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/dafc7c017d1f62e2190a20dc84a52fbfc4c70210.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
A klp relocation section is .klp.rela.<objname>.<secname>, where objname
is the object being patched.
klp-build wrongly derives objname from where the referenced symbol
lives, not where it's referenced. For a cross-module reference like
patched can_isotp code calling can.ko's can_rx_unregister(), that gives
.klp.rela.can..text rather than .klp.rela.can_isotp..text. Unless the
patch happens to patch can.ko as well, the relocation never gets applied
and the call goes off into the weeds.
Name the intermediate section __klp_relocs.<objname> so post-link can
read the patched object's name from there.
Fixes: dd590d4d57 ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://lore.kernel.org/20260720145658.1103243-2-joe.lawrence@redhat.com
Acked-by: Song Liu <song@kernel.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/ee93a08f3e55e76ffa67d04e283917ddaa893f09.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Explicitly disallow the patching and referencing of init code/data.
Otherwise it could potentially introduce some odd edge cases depending
on whether the target object's init section has been freed yet (note
that the init code still exists in the target module when doing late
module patching).
Such edge cases include sympos calculation and the patching and/or
referencing of non-existent (init-freed) code/data. Not to mention the
inherent differences in behavior that occur when the init code is only
patched *some* of the time depending on module loading order or kernel
config.
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/516e14f84cfbffa27dc19d3dcf35097504097966.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
An x86 alternative with an empty replacement, e.g. the second entry of
ALTERNATIVE_2("orig", "repl", ft1, "", ft2)
has a replacementlen of zero. Its replacement offset still gets a
relocation, but the label it points at is the end of the previous
replacement, which is also the beginning of the *next* alternative's
replacement. The value is meaningless; get_alt_entry() already ignores
it for that reason.
klp diff doesn't ignore it. When such an alternative belongs to a
changed function, cloning its relocations drags in the unrelated
neighboring replacement, along with everything that replacement
references. On an x86 clang/lto build an empty alternative in
meminfo_proc_show() pulled in the replacement of an alternative in
proc_kcore_init(), silently emitting a klp relocation against init text
which has long since been freed by the time the patch is applied.
Add arch_alt_ignore_new_reloc() and skip such relocations when cloning.
This has to be arch specific: on arm64 a zero-length replacement instead
identifies an alternative callback, whose replacement offset points at
the callback function and must be preserved.
Fixes: dd590d4d57 ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Acked-by: Song Liu <song@kernel.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/7a885b70974795c3417f3358869e62aafd4ef783.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
create_fake_symbols() sizes each ANNOTATE_DATA_SPECIAL entry from the
offset of the next annotation, falling back to the end of the section
for the last entry. But the last entry is detected by a zero size,
which also happens for an *empty* entry: ALTERNATIVE(oldinstr, "", ft)
still annotates its zero-length replacement, at the same offset as the
next entry's annotation.
So every empty replacement gets a fake symbol spanning the entire rest
of .altinstr_replacement. That's harmless today only because
find_symbol_containing() picks the smaller of two overlapping symbols.
Track whether a next annotation was found rather than inferring it from
the size. A zero-length fake symbol is fine: find_symbol_containing()
skips those, so the properly sized symbol at the same offset still wins.
Fixes: dd590d4d57 ("objtool/klp: Introduce klp diff subcommand for diffing object files")
Acked-by: Song Liu <song@kernel.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/913e691c5009397df832c7c9a18cd5cf71b42737.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Testing klp-build with arm64 produced the following linker error during
the original kernel build:
`__notrim.1' referenced in section `.klp.symid' of vmlinux.o: defined in discarded section `.no_trim_symbol' of vmlinux.o
symbol_get() puts a static __notrim[] in .no_trim_symbol, which GCC
names __notrim.1, __notrim.2, etc. Two or more built-in translation
units calling symbol_get() thus produce duplicate names, resulting in
corresponding .klp.symid references which trigger the above error.
Add .no_trim_symbol to the discarded section list so its symbols don't
get symids.
Note this issue is not specific to arm64: it just needs two built-in
symbol_get() callers. arm64 trips over it easily because it has KVM
always compiled in vmlinux, whereas on x86 it's typically a module.
Fixes: 029223d301 ("objtool/klp: Add .klp.symid for sympos disambiguation")
Acked-by: Song Liu <song@kernel.org>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/5a3cc4cded743167dd0878220201d80f7e48e5d7.1786138493.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
That flag exists to stop gas emulating instructions the assembler thinks
the target lacks. It is a gas-only option, and LLVM's integrated
assembler does not emulate instructions in the first place, so nothing
is needed there.
Condition it on CONFIG_AS_IS_GNU rather than the compiler, so it is
still passed for clang builds using GNU as (LLVM_IAS=0) and omitted only
for the integrated assembler.
Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://lore.kernel.org/r/20260805185557.3283233-1-mattst88@gmail.com
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
do_entInt() opens with local_irq_disable(), which with
CONFIG_TRACE_IRQFLAGS only calls trace_hardirqs_off() if interrupts were
not already off:
#define local_irq_disable() \
do { \
bool was_disabled = raw_irqs_disabled();\
raw_local_irq_disable(); \
if (!was_disabled) \
trace_hardirqs_off(); \
} while (0)
On alpha raw_irqs_disabled() is (rdps() & 7) == IPL_MAX, i.e. IPL 7.
PALcode raises PS.IPL to the level of the interrupt before entInt runs,
so for an IPL 7 entry - a processor machine check (vector 0x660) or a
system event (vector 0x680), both IPL_MCHECK == IPL_MAX - the gate is
already true and the annotation is skipped. lockdep keeps whatever
hardirq state the interrupted context had. If that context had
interrupts enabled, lockdep believes they are still enabled for the
duration of the handler, and every lockdep_assert_irqs_disabled() in the
interrupt path fires:
WARNING: kernel/context_tracking.c:346 at ct_irq_enter+0xc4/0xd0, CPU#0: swapper/0/0
[...]
[<fffffc0001ef74d4>] ct_irq_enter+0xc4/0xd0
[<fffffc000105ebd0>] irq_enter+0x20/0x50
[<fffffc000103707c>] do_entInt+0x1dc/0x2e0
[<fffffc0001031d60>] ret_from_exception+0x0/0x10
irq event stamp: 735356346
hardirqs last enabled at (735356346): trace_hardirqs_on+0x68/0x220
hardirqs last disabled at (735356345): do_idle+0xf0/0x270
The stamps show the problem directly: the most recent event is the
enable from the interrupted idle loop, and do_entInt() recorded no
disable at all. ct_irq_exit() warns the same way on the way out.
Ordinary device interrupts arrive at IPL 3-5 and IPIs and performance
counter interrupts at IPL 6, so was_disabled is false for them and the
annotation happens normally. Only the two IPL 7 vectors are affected,
which is why this needs an environmental event to show up.
Take the hardware IPL out of the decision and drive the annotation from
lockdep's own state instead.
This corrects the annotation only. An IPL 7 event can also interrupt a
region that has legitimately disabled interrupts, where irq_enter() and
irq_exit() are not the right primitives and NMI semantics are needed;
that is a larger change and is left alone here.
Tested on an AlphaServer ES47 (Marvel/EV7) by injecting system events
through the system management path: fifteen injections, idle and under
load, with no splat. The same injection on a freshly booted kernel
without this change reproduces both warnings.
Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://lore.kernel.org/r/20260810202835.3592833-2-mattst88@gmail.com
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
On Marvel the CMOS clock is only reachable from the boot cpu, so
remote_read_time() and remote_set_time() bounce the access there with
smp_call_function_single(), whose callback runs in hard interrupt
context.
alpha_rtc_read_time() calls mc146818_get_time() with a 10 ms timeout.
That waits out the RTC update cycle in mc146818_avoid_UIP(), which drops
rtc_lock and udelay()s 100 us at a time until the update completes or
the timeout expires:
for (i = 0; UIP_RECHECK_LOOPS_MS(i) < timeout; i++) {
spin_lock_irqsave(&rtc_lock, flags);
...
if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) {
spin_unlock_irqrestore(&rtc_lock, flags);
udelay(UIP_RECHECK_DELAY);
continue;
}
So a clock read from a non-boot cpu can spin for up to 10 ms in hard
interrupt context on the boot cpu, while the cpu that sent the request
spins in smp_call_function_single() waiting for it to finish.
mc146818_set_time() does not poll, but it takes rtc_lock too, and
rtc_lock is a spinlock_t. Only raw spinlocks may be taken in hard
interrupt context, so lockdep reports the write path as soon as a
non-boot cpu sets the clock:
[ BUG: Invalid wait context ]
-----------------------------
swapper/0/0 is trying to lock:
fffffc0003690470 (rtc_lock){....}-{3:3}, at: mc146818_set_time+0x74/0x450
other info that might help us debug this:
context-{2:2}
no locks held by swapper/0/0.
stack backtrace:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 7.2.0-rc1 #1 NONE
Trace:
[<fffffc000102ebb0>] dump_stack+0x28/0x44
[<fffffc000110efcc>] __lock_acquire+0xb0c/0x1060
[<fffffc000110f5f0>] lock_acquire.part.0+0xd0/0x300
[...]
[<fffffc0001b0d834>] mc146818_set_time+0x74/0x450
[<fffffc0001f090cc>] _raw_spin_lock_irqsave+0x7c/0xc0
[<fffffc0001042f90>] do_remote_set+0x90/0xc0
[<fffffc000119c1a4>] __flush_smp_call_function_queue+0x314/0x5c0
[<fffffc000119c474>] generic_smp_call_function_single_interrupt+0x24/0x40
[<fffffc000103d984>] handle_ipi+0xa4/0x230
[<fffffc0001037044>] do_entInt+0x1a4/0x2e0
The rtc class ops are always called from process context, so there is no
reason to run the access from an interrupt at all. Use work_on_cpu() to
run it in a worker on the boot cpu. Alpha does not support cpu hotplug,
so the boot cpu cannot go offline while the work is pending.
Tested on an AlphaServer ES47 (Marvel/EV7): hwclock read and write
pinned to a non-boot cpu, twenty times, with no splat.
Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://lore.kernel.org/r/20260810202835.3592833-1-mattst88@gmail.com
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Md Sadre Alam <md.alam@oss.qualcomm.com> says:
The Qualcomm QPIC SPI-NAND controller supports both single (x1) and
quad (x4) transfer modes, however the current driver operates only in
single-bit mode. This series adds support for quad data transfers and
includes a vendor-specific fix required for Macronix SPI-NAND devices.
Link: https://patch.msgid.link/20260807-quad-v2-0-8ec821e2f22b@oss.qualcomm.com
Macronix SPI-NAND devices use opcode 0x6b for quad output cache reads,
while most other devices use opcode 0xeb. The QPIC SPI-NAND driver does
not currently recognize opcode 0x6b, causing read operations to fail
when Macronix devices select this cache read variant.
Add the Macronix-specific read opcode to the command mapping logic and
treat it the same as the existing quad read operations.
This allows Macronix SPI-NAND devices to operate correctly in quad read
mode.
Signed-off-by: Md Sadre Alam <md.alam@oss.qualcomm.com>
Link: https://patch.msgid.link/20260807-quad-v2-3-8ec821e2f22b@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Add support for quad (x4) transfer mode in the QPIC SPI NAND driver.
The controller supports both single (x1) and quad (x4) SPI transfers,
but the driver currently operates only in x1 mode.
Track the QUAD enable state from the device configuration register
(0xB0) and switch the data transfer width accordingly. When the core
enables quad mode, use x4 transfers for read and program operations to
improve throughput.
Introduce a quad_mode flag in struct qpic_spi_nand to cache the current
device state. The flag is updated based on GET_FEATURE responses from
the configuration register.
Signed-off-by: Md Sadre Alam <md.alam@oss.qualcomm.com>
Link: https://patch.msgid.link/20260807-quad-v2-2-8ec821e2f22b@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Move qcom_spi_cmd_mapping() above qcom_spi_read_page() so it can be
used by read path changes added in a subsequent patch.
No functional change.
Signed-off-by: Md Sadre Alam <md.alam@oss.qualcomm.com>
Link: https://patch.msgid.link/20260807-quad-v2-1-8ec821e2f22b@oss.qualcomm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
On EV6 and later the hardware records exception status bits in the FPCR
before delivering a software completion trap, and those bits can be wrong
for the instruction that trapped. Converting a double that is exactly
representable as a subnormal float sets FPCR_UNF even though the result
is exact, and an underflow trap additionally sets FPCR_INE even when the
emulated operation turns out to be exact.
alpha_fp_emul() only wrote the FPCR when soft-fp raised an exception, so
whenever it determined that the instruction was exact the fabricated bits
stayed in the FPCR and were reported to user space by fetestexcept().
Pass the exception summary register down from do_entArith() so the
handler can tell which exceptions the hardware attributed to the trapping
instruction, and always write the FPCR. Clear the exceptions that the
trap reported but that soft-fp did not raise. EXC_SUM reports only the
underflow or overflow when the hardware also set INE, so treat INE as a
candidate in that case, and treat a trap with no reported exception as a
denormal operand trap, for which the hardware can fabricate INE and UNF
as well. Bits that software has already confirmed in ieee_state belong
to this or an earlier instruction and are never cleared.
The imprecise path passes no summary. There the trap was taken somewhere
in the trap shadow, so EXC_SUM is not attribution for the instruction
being re-executed -- and only EV6, which traps precisely and so never
takes that path, has fabricated bits to clear. For the same reason the
clearing is guarded by implver(), matching swcr_update_status().
On an UP1500 (EV68) this takes the glibc math testsuite from 831 failures
to 28, the remainder being unrelated to exception status.
This belongs with the preceding fix to ieee_swcr_to_fpcr(), and should
not be backported without it -- nor it without this. That fix stops
FPCR_DNOD being set unconditionally, so denormal operand traps start
firing again. Those traps very often find an exact result, which is
precisely the case where the old code left the FPCR unwritten and the
fabricated bits visible. Applied alone it would make spurious exception
flags more common, not less.
One case cannot be resolved here: an inexact instruction without the
software completion suffix never traps, so its INE reaches the FPCR
without being recorded anywhere else. Such a bit is indistinguishable
from an INE the hardware fabricated for a trapping instruction, and is
lost if an underflow or overflow trap with an exact result follows it.
The FPCR is the only record of those instructions and it carries no
attribution.
The bug predates the git history, so there is no commit to reference in a
Fixes tag.
Cc: stable@vger.kernel.org # 5.15+
Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://lore.kernel.org/r/20260803-alpha-fp-exceptions-v1-2-c99d75608e60@gmail.com
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
ieee_swcr_to_fpcr() converts the software IEEE trap-enable and status
bits kept in thread_info.ieee_state into the hardware FPCR format. It
contained:
fp |= (~sw & IEEE_TRAP_ENABLE_DNO) << 41;
FPCR_DNOD (bit 47) disables denormal operand traps: with it set the
hardware handles a denormal operand itself, treating it as zero, instead
of trapping for software completion. The intent was to set DNOD when the
user has not asked for SIGFPE on denormal operands, but
IEEE_TRAP_ENABLE_DNO is clear by default, so ieee_swcr_to_fpcr(0) always
set DNOD.
Instructions built with the software completion suffix therefore never
trapped on a denormal operand. The hardware silently substituted zero
and produced wrong results, affecting every program compiled with -mieee
and default FPU settings, glibc included.
Set FPCR_DNOD only when IEEE_MAP_DMZ is requested, which is exactly the
case where flushing denormal inputs to zero is what the user asked for.
DNOD then encodes MAP_DMZ, which ieee_fpcr_to_swcr() already recovers
from FPCR_DNZ, so drop its attempt to recover IEEE_TRAP_ENABLE_DNO from
DNOD; the DNO trap enable lives solely in ieee_state.
Both functions are in a uapi header, so the encoding change is visible to
userspace, but nothing outside the kernel is known to depend on DNOD
carrying the DNO trap enable, and the kernel is the only writer of the
FPCR.
This must not be backported on its own. Re-enabling denormal operand
traps exposes a second bug, fixed in the following patch: those traps
usually find an exact result, and for an exact result the emulator did
not write the FPCR back, leaving hardware-fabricated exception bits
visible to user space. Taken alone this change would make spurious
exception flags more common.
The bug predates the git history, so there is no commit to reference in a
Fixes tag.
Cc: stable@vger.kernel.org # 5.15+
Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://lore.kernel.org/r/20260803-alpha-fp-exceptions-v1-1-c99d75608e60@gmail.com
Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
Mark the fair policy as experimental until reported regressions are
addressed.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Luke.Wildhardt@proton.me
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Philipp Stanner <phasta@kernel.org>
Cc: Christian König <ckoenig.leichtzumerken@gmail.com>
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20260811163139.99746-20-tvrtko.ursulin@igalia.com