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1,447,411 commits

Author SHA1 Message Date
Roman Gushchin
6e57cdde70 MAINTAINERS: add an entry for MM BPF extensions
Let's create a separate entry for MM BPF extensions: these patches
often require an attention from both bpf and mm communities.

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Link: https://lore.kernel.org/r/20251223044156.208250-7-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:22 -08:00
JP Kobryn
6bce6ddbe6 bpf: selftests: selftests for memcg stat kfuncs
Add test coverage for the kfuncs that fetch memcg stats. Using some common
stats, test scenarios ensuring that the given stat increases by some
arbitrary amount. The stats selected cover the three categories represented
by the enums: node_stat_item, memcg_stat_item, vm_event_item.

Since only a subset of all stats are queried, use a static struct made up
of fields for each stat. Write to the struct with the fetched values when
the bpf program is invoked and read the fields in the user mode program for
verification.

Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Link: https://lore.kernel.org/r/20251223044156.208250-6-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:22 -08:00
Roman Gushchin
99430ab8b8 mm: introduce BPF kfuncs to access memcg statistics and events
Introduce BPF kfuncs to conveniently access memcg data:
  - bpf_mem_cgroup_vm_events(),
  - bpf_mem_cgroup_memory_events(),
  - bpf_mem_cgroup_usage(),
  - bpf_mem_cgroup_page_state(),
  - bpf_mem_cgroup_flush_stats().

These functions are useful for implementing BPF OOM policies, but
also can be used to accelerate access to the memcg data. Reading
it through cgroupfs is much more expensive, roughly 5x, mostly
because of the need to convert the data into the text and back.

JP Kobryn:
An experiment was setup to compare the performance of a program that
uses the traditional method of reading memory.stat vs a program using
the new kfuncs. The control program opens up the root memory.stat file
and for 1M iterations reads, converts the string values to numeric data,
then seeks back to the beginning. The experimental program sets up the
requisite libbpf objects and for 1M iterations invokes a bpf program
which uses the kfuncs to fetch all available stats for node_stat_item,
memcg_stat_item, and vm_event_item types.

The results showed a significant perf benefit on the experimental side,
outperforming the control side by a margin of 93%. In kernel mode,
elapsed time was reduced by 80%, while in user mode, over 99% of time
was saved.

control: elapsed time
real    0m38.318s
user    0m25.131s
sys     0m13.070s

experiment: elapsed time
real    0m2.789s
user    0m0.187s
sys     0m2.512s

control: perf data
33.43% a.out libc.so.6         [.] __vfscanf_internal
 6.88% a.out [kernel.kallsyms] [k] vsnprintf
 6.33% a.out libc.so.6         [.] _IO_fgets
 5.51% a.out [kernel.kallsyms] [k] format_decode
 4.31% a.out libc.so.6         [.] __GI_____strtoull_l_internal
 3.78% a.out [kernel.kallsyms] [k] string
 3.53% a.out [kernel.kallsyms] [k] number
 2.71% a.out libc.so.6         [.] _IO_sputbackc
 2.41% a.out [kernel.kallsyms] [k] strlen
 1.98% a.out a.out             [.] main
 1.70% a.out libc.so.6         [.] _IO_getline_info
 1.51% a.out libc.so.6         [.] __isoc99_sscanf
 1.47% a.out [kernel.kallsyms] [k] memory_stat_format
 1.47% a.out [kernel.kallsyms] [k] memcpy_orig
 1.41% a.out [kernel.kallsyms] [k] seq_buf_printf

experiment: perf data
10.55% memcgstat bpf_prog_..._query [k] bpf_prog_16aab2f19fa982a7_query
 6.90% memcgstat [kernel.kallsyms]  [k] memcg_page_state_output
 3.55% memcgstat [kernel.kallsyms]  [k] _raw_spin_lock
 3.12% memcgstat [kernel.kallsyms]  [k] memcg_events
 2.87% memcgstat [kernel.kallsyms]  [k] __memcg_slab_post_alloc_hook
 2.73% memcgstat [kernel.kallsyms]  [k] kmem_cache_free
 2.70% memcgstat [kernel.kallsyms]  [k] entry_SYSRETQ_unsafe_stack
 2.25% memcgstat [kernel.kallsyms]  [k] __memcg_slab_free_hook
 2.06% memcgstat [kernel.kallsyms]  [k] get_page_from_freelist

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Co-developed-by: JP Kobryn <inwardvessel@gmail.com>
Signed-off-by: JP Kobryn <inwardvessel@gmail.com>
Link: https://lore.kernel.org/r/20251223044156.208250-5-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:22 -08:00
Roman Gushchin
5c7db3239c mm: introduce bpf_get_root_mem_cgroup() BPF kfunc
Introduce a BPF kfunc to get a trusted pointer to the root memory
cgroup. It's very handy to traverse the full memcg tree, e.g.
for handling a system-wide OOM.

It's possible to obtain this pointer by traversing the memcg tree
up from any known memcg, but it's sub-optimal and makes BPF programs
more complex and less efficient.

bpf_get_root_mem_cgroup() has a KF_ACQUIRE | KF_RET_NULL semantics,
however in reality it's not necessary to bump the corresponding
reference counter - root memory cgroup is immortal, reference counting
is skipped, see css_get(). Once set, root_mem_cgroup is always a valid
memcg pointer. It's safe to call bpf_put_mem_cgroup() for the pointer
obtained with bpf_get_root_mem_cgroup(), it's effectively a no-op.

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Link: https://lore.kernel.org/r/20251223044156.208250-4-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:21 -08:00
Roman Gushchin
5904db9891 mm: introduce BPF kfuncs to deal with memcg pointers
To effectively operate with memory cgroups in BPF there is a need
to convert css pointers to memcg pointers. A simple container_of
cast which is used in the kernel code can't be used in BPF because
from the verifier's point of view that's a out-of-bounds memory access.

Introduce helper get/put kfuncs which can be used to get
a refcounted memcg pointer from the css pointer:
  - bpf_get_mem_cgroup,
  - bpf_put_mem_cgroup.

bpf_get_mem_cgroup() can take both memcg's css and the corresponding
cgroup's "self" css. It allows it to be used with the existing cgroup
iterator which iterates over cgroup tree, not memcg tree.

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Link: https://lore.kernel.org/r/20251223044156.208250-3-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:21 -08:00
Roman Gushchin
4221de8c41 mm: declare memcg_page_state_output() in memcontrol.h
To use memcg_page_state_output() in bpf_memcontrol.c move the
declaration from v1-specific memcontrol-v1.h to memcontrol.h.

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://lore.kernel.org/r/20251223044156.208250-2-roman.gushchin@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-12-22 22:20:21 -08:00
Rohit Chourasia
af04c1e8e7 wifi: rtlwifi: fix typo 'received' in comment
Fix typo received -> received by review.

Signed-off-by: Rohit Chourasia <chourasiarohit27@gmail.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251211161911.30611-1-chourasiarohit27@gmail.com
2025-12-23 13:22:50 +08:00
Zqiang
714d81423e sched_ext: Avoid multiple irq_work_queue() calls in destroy_dsq()
llist_add() returns true only when adding to an empty list, which indicates
that no IRQ work is currently queued or running. Therefore, we only need to
call irq_work_queue() when llist_add() returns true, to avoid unnecessarily
re-queueing IRQ work that is already pending or executing.

Signed-off-by: Zqiang <qiang.zhang@linux.dev>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-22 17:55:41 -10:00
Zqiang
ccaeeb585c sched_ext: Use the resched_cpu() to replace resched_curr() in the bypass_lb_node()
For the PREEMPT_RT kernels, the scx_bypass_lb_timerfn() running in the
preemptible per-CPU ktimer kthread context, this means that the following
scenarios will occur(for x86 platform):

       cpu1                          cpu2
				 ktimer kthread:
                                 ->scx_bypass_lb_timerfn
                                   ->bypass_lb_node
                                     ->for_each_cpu(cpu, resched_mask)

    migration/1:                       by preempt by migration/2:
    multi_cpu_stop()                     multi_cpu_stop()
    ->take_cpu_down()
      ->__cpu_disable()
	->set cpu1 offline

                                       ->rq1 = cpu_rq(cpu1)
                                       ->resched_curr(rq1)
                                         ->smp_send_reschedule(cpu1)
					   ->native_smp_send_reschedule(cpu1)
					     ->if(unlikely(cpu_is_offline(cpu))) {
                					WARN(1, "sched: Unexpected
							reschedule of offline CPU#%d!\n", cpu);
                					return;
        					}

This commit therefore use the resched_cpu() to replace resched_curr()
in the bypass_lb_node() to avoid send-ipi to offline CPUs.

Signed-off-by: Zqiang <qiang.zhang@linux.dev>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-22 17:51:51 -10:00
Ping-Ke Shih
d3a9e132a4 wifi: rtw89: correct use sequence of driver_data in skb->info
As ieee80211_tx_info is used to assist filling TX descriptor, and layout of
IEEE80211_SKB_CB(skb)->driver_data (accessing by RTW89_TX_SKB_CB()) is
union, so driver_data must be used by/after rtw89_hci_tx_write() or just
before calling rtw89_hci_tx_write(). Otherwise, ieee80211_tx_info::control
data is overwritten.

Found this by using injected packets which uses ieee80211_tx_info::control,
but always sending incorrect data rate.

Cc: Fedor Pchelkin <pchelkin@ispras.ru>
Fixes: d5da3d9fb0 ("wifi: rtw89: process TX wait skbs for USB via C2H handler")
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Tested-by: Fedor Pchelkin <pchelkin@ispras.ru>
Link: https://patch.msgid.link/20251217072646.43209-1-pkshih@realtek.com
2025-12-23 11:50:33 +08:00
Jan Gerber
a2f1fc9ab6 wifi: rtw89: 8852au: add support for TP TX30U Plus
the device shows up like this and everything seams to work:

Bus 004 Device 003: ID 3625:010d Realtek 802.11ax WLAN Adapter

Signed-off-by: Jan Gerber <j@mailb.org>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251212005515.2059533-1-j@mailb.org
2025-12-23 11:49:06 +08:00
Marco Crivellari
36f2deb2f5 wifi: rtw89: add WQ_PERCPU to alloc_workqueue users
This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

   commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
   commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

The refactoring is going to alter the default behavior of
alloc_workqueue() to be unbound by default.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU. For more details see the Link tag below.

In order to keep alloc_workqueue() behavior identical, explicitly request
WQ_PERCPU.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251210101209.47176-1-marco.crivellari@suse.com
2025-12-23 11:45:02 +08:00
Jose Ignacio Tornos Martinez
41be33d3ef wifi: rtw89: 8922a: set random mac if efuse contains zeroes
I have some rtl8922ae devices with no permanent mac stored in efuse.

It could be properly saved and/or configured from user tools like
NetworkManager, but it would be desirable to be able to initialize it
somehow to get the device working by default.

So, in the same way as with other devices, if the mac address read from
efuse contains zeros, a random mac address is assigned to at least allow
operation, and the user is warned about this in case any action needs to
be considered.

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251126091905.217951-1-jtornosm@redhat.com
2025-12-23 11:42:38 +08:00
Chen Ridong
269679bdd1 cpuset: remove dead code in cpuset-v1.c
The commit 6e1d31ce49 ("cpuset: separate generate_sched_domains for v1
and v2") introduced dead code that was originally added for cpuset-v2
partition domain generation. Remove the redundant root_load_balance check.

Fixes: 6e1d31ce49 ("cpuset: separate generate_sched_domains for v1 and v2")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/cgroups/9a442808-ed53-4657-988b-882cc0014c0d@huaweicloud.com/T/
Signed-off-by: Chen Ridong <chenridong@huawei.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-22 17:40:17 -10:00
Hsiu-Ming Chang
77653c327e wifi: rtw88: rtw8821cu: Add ID for Mercusys MU6H
Add support for Mercusys MU6H AC650 High Gain Wireless Dual Band USB
Adapter V1.30. It is based on RTL8811CU, usb device ID is 2c4e:0105.

Signed-off-by: Hsiu-Ming Chang <cges30901@gmail.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251205003245.5762-1-cges30901@gmail.com
2025-12-23 11:38:05 +08:00
Bitterblue Smith
44d1f624bb wifi: rtw88: 8822b: Avoid WARNING in rtw8822b_config_trx_mode()
rtw8822b_set_antenna() can be called from userspace when the chip is
powered off. In that case a WARNING is triggered in
rtw8822b_config_trx_mode() because trying to read the RF registers
when the chip is powered off returns an unexpected value.

Call rtw8822b_config_trx_mode() in rtw8822b_set_antenna() only when
the chip is powered on.

------------[ cut here ]------------
write RF mode table fail
WARNING: CPU: 0 PID: 7183 at rtw8822b.c:824 rtw8822b_config_trx_mode.constprop.0+0x835/0x840 [rtw88_8822b]
CPU: 0 UID: 0 PID: 7183 Comm: iw Tainted: G        W  OE       6.17.5-arch1-1 #1 PREEMPT(full)  01c39fc421df2af799dd5e9180b572af860b40c1
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: LENOVO 82KR/LNVNB161216, BIOS HBCN18WW 08/27/2021
RIP: 0010:rtw8822b_config_trx_mode.constprop.0+0x835/0x840 [rtw88_8822b]
Call Trace:
 <TASK>
 rtw8822b_set_antenna+0x57/0x70 [rtw88_8822b 370206f42e5890d8d5f48eb358b759efa37c422b]
 rtw_ops_set_antenna+0x50/0x80 [rtw88_core 711c8fb4f686162be4625b1d0b8e8c6a5ac850fb]
 ieee80211_set_antenna+0x60/0x100 [mac80211 f1845d85d2ecacf3b71867635a050ece90486cf3]
 nl80211_set_wiphy+0x384/0xe00 [cfg80211 296485ee85696d2150309a6d21a7fbca83d3dbda]
 ? netdev_run_todo+0x63/0x550
 genl_family_rcv_msg_doit+0xfc/0x160
 genl_rcv_msg+0x1aa/0x2b0
 ? __pfx_nl80211_pre_doit+0x10/0x10 [cfg80211 296485ee85696d2150309a6d21a7fbca83d3dbda]
 ? __pfx_nl80211_set_wiphy+0x10/0x10 [cfg80211 296485ee85696d2150309a6d21a7fbca83d3dbda]
 ? __pfx_nl80211_post_doit+0x10/0x10 [cfg80211 296485ee85696d2150309a6d21a7fbca83d3dbda]
 ? __pfx_genl_rcv_msg+0x10/0x10
 netlink_rcv_skb+0x59/0x110
 genl_rcv+0x28/0x40
 netlink_unicast+0x285/0x3c0
 ? __alloc_skb+0xdb/0x1a0
 netlink_sendmsg+0x20d/0x430
 ____sys_sendmsg+0x39f/0x3d0
 ? import_iovec+0x2f/0x40
 ___sys_sendmsg+0x99/0xe0
 ? refill_obj_stock+0x12e/0x240
 __sys_sendmsg+0x8a/0xf0
 do_syscall_64+0x81/0x970
 ? do_syscall_64+0x81/0x970
 ? ksys_read+0x73/0xf0
 ? do_syscall_64+0x81/0x970
 ? count_memcg_events+0xc2/0x190
 ? handle_mm_fault+0x1d7/0x2d0
 ? do_user_addr_fault+0x21a/0x690
 ? exc_page_fault+0x7e/0x1a0
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
 </TASK>
---[ end trace 0000000000000000 ]---

Link: https://github.com/lwfinger/rtw88/issues/366
Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/fb9a3444-9319-4aa2-8719-35a6308bf568@gmail.com
2025-12-23 11:32:48 +08:00
Roman Peshkichev
9f68fdcdc9 wifi: rtw88: fix DTIM period handling when conf->dtim_period is zero
The function rtw_set_dtim_period() accepted an 'int' dtim_period parameter,
while mac80211 provides dtim_period as 'u8' in struct ieee80211_bss_conf.
In IBSS (ad-hoc) mode mac80211 may set dtim_period to 0.

The driver unconditionally wrote (dtim_period - 1) to
REG_DTIM_COUNTER_ROOT, which resulted in 0xFF when dtim_period was 0. This
caused delays in broadcast/multicast traffic processing and issues with
ad-hoc operation.

Convert the function parameter to u8 to match ieee80211_bss_conf and avoid
the underflow by writing 0 when dtim_period is 0.

Link: https://github.com/lwfinger/rtw88/issues/406
Signed-off-by: Roman Peshkichev <roman.peshkichev@gmail.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20251125180937.22977-1-roman.peshkichev@gmail.com
2025-12-23 11:26:07 +08:00
Inochi Amaoto
99735a742f
clk: spacemit: Hide common clock driver from user controller
Since the common clock driver is only a dependency for other spacemit
clock driver, it should not be enabled individually, so hide this in
the Kconfig UI and let other spacemit clock driver select it.

Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20251219012819.440972-3-inochiama@gmail.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>
2025-12-23 10:28:31 +08:00
Inochi Amaoto
5ec8cbbc54
clk: spacemit: Respect Kconfig setting when building modules
Currently, the SPACEMIT_CCU entry is only a switch for enabling entry
SPACEMIT_K1_CCU. It does not guide the build for common clock codes
even if it is a tristate entry. This makes this entry useless.

Change the Makefile to add a separate build for common clock logic,
so the SPACEMIT_CCU entry takes effect, also add necessary
MODULE_LICENSE()/MODULE_DESCRIPTION()/EXPORT_SYMBOL() for the module
build.

Fixes: 1b72c59db0 ("clk: spacemit: Add clock support for SpacemiT K1 SoC")
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20251219012819.440972-2-inochiama@gmail.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>
2025-12-23 10:28:28 +08:00
Ryusuke Konishi
6fd8a09f48 nilfs2: fix missing struct keywords in nilfs2_api.h kernel-doc
Eliminate the following kernel-doc warnings in nilfs2_api.h:

Warning: include/uapi/linux/nilfs2_api.h:65 cannot understand function
 prototype: 'struct nilfs_suinfo'
Warning: include/uapi/linux/nilfs2_api.h:101 cannot understand function
 prototype: 'struct nilfs_suinfo_update'

This ensures that the documentation for nilfs_suinfo and
nilfs_suinfo_update is correctly parsed and generated by adding the
missing 'struct' keyword to their kernel-doc comments.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2025-12-22 15:45:29 -08:00
Randy Dunlap
cb8fe62f87 nilfs2: convert nilfs_super_block to kernel-doc
Eliminate 40+ kernel-doc warnings in nilfs2_ondisk.h by converting
all of the struct member comments to kernel-doc comments.

Fix one misnamed struct member in nilfs_direct_node.

Object files before and after are the same size and content.

Examples of warnings:
Warning: include/uapi/linux/nilfs2_ondisk.h:202 struct member 's_rev_level'
 not described in 'nilfs_super_block'
Warning: include/uapi/linux/nilfs2_ondisk.h:202 struct member
 's_minor_rev_level' not described in 'nilfs_super_block'
Warning: include/uapi/linux/nilfs2_ondisk.h:202 struct member 's_magic'
 not described in 'nilfs_super_block'
Warning: include/uapi/linux/nilfs2_ondisk.h:202 struct member 's_bytes'
 not described in 'nilfs_super_block'
Warning: include/uapi/linux/nilfs2_ondisk.h:202 struct member 's_flags'
 not described in 'nilfs_super_block'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2025-12-22 15:45:29 -08:00
Edward Adam Davis
ed527ef0c2 nilfs2: Fix potential block overflow that cause system hang
When a user executes the FITRIM command, an underflow can occur when
calculating nblocks if end_block is too small. Since nblocks is of
type sector_t, which is u64, a negative nblocks value will become a
very large positive integer. This ultimately leads to the block layer
function __blkdev_issue_discard() taking an excessively long time to
process the bio chain, and the ns_segctor_sem lock remains held for a
long period. This prevents other tasks from acquiring the ns_segctor_sem
lock, resulting in the hang reported by syzbot in [1].

If the ending block is too small, typically if it is smaller than 4KiB
range, depending on the usage of the segment 0, it may be possible to
attempt a discard request beyond the device size causing the hang.

Exiting successfully and assign the discarded size (0 in this case)
to range->len.

Although the start and len values in the user input range are too small,
a conservative strategy is adopted here to safely ignore them, which is
equivalent to a no-op; it will not perform any trimming and will not
throw an error.

[1]
task:segctord state:D stack:28968 pid:6093 tgid:6093  ppid:2 task_flags:0x200040 flags:0x00080000
Call Trace:
 rwbase_write_lock+0x3dd/0x750 kernel/locking/rwbase_rt.c:272
 nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357
 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2569 [inline]
 nilfs_segctor_thread+0x6ec/0xe00 fs/nilfs2/segment.c:2684

[ryusuke: corrected part of the commit message about the consequences]

Fixes: 82e11e857b ("nilfs2: add nilfs_sufile_trim_fs to trim clean segs")
Reported-by: syzbot+7eedce5eb281acd832f0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7eedce5eb281acd832f0
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
2025-12-22 15:45:29 -08:00
Lukas Bulwahn
7f3c3a0a91 MAINTAINERS: Add doc files on real-time support to Real-time Linux
Commit f51fe3b7e4 ("Documentation: Add real-time to core-api") adds new
documentation on real-time support, i.e., PREEMPT_RT. So, add a file entry
for that directory to the corresponding section in MAINTAINERS.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251127154343.292156-4-bigeasy@linutronix.de>
2025-12-22 15:33:40 -07:00
Lukas Bulwahn
6c95f2d67f Documentation: update config name in real-time architecture support
Commit 4843a45ef9fe8 ("entry: Rename "kvm" entry code assets to "virt"
to genericize APIs") renames the config KVM_XFER_TO_GUEST_WORK to
VIRT_XFER_TO_GUEST_WORK.

Adjust the documentation to the current situation, and specifically
refer to the new name of the config.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251127154343.292156-3-bigeasy@linutronix.de>
2025-12-22 15:33:40 -07:00
Sebastian Andrzej Siewior
7548c69f51 Documentation: Add some hardware hints for real-time
Some thoughts on hardware that is used for real-time workload. Certainly
not complete but should cover some of the import topics such as:

- Main memory, caches and the possiblie control given by the hardware.
- What could happen by putting critical hardware behind USB or VirtIO.
- Allowing real-time tasks to consume the CPU entirely without giving
  the system some time to breath.
- Networking with what the kernel provides.

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251127154343.292156-2-bigeasy@linutronix.de>
2025-12-22 15:33:40 -07:00
Willy Tarreau
ceddb2c001 Documentation: insist on the plain-text requirement for security reports
As the trend of AI-generated reports is growing, the trend of unreadable
reports in gimmicky formats is following, and we cannot request that
developers rely on online viewers to be able to read a security report
full for formatting tags. Let's just insist on the plain text requirement
a bit more.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251129141741.19046-1-w@1wt.eu>
2025-12-22 15:32:03 -07:00
Uwe Kleine-König
273aa250f1 Documentation: Improve wording on requirements for a free Nitrokey
"listed in MAINTAINERS" is not enough to qualify for the free Nitrokey
Start. You have to be listed in an M: entry. Mention that to reduce
confusion for reviewers who wonder why their application fails.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251203074349.1826233-2-u.kleine-koenig@baylibre.com>
2025-12-22 15:30:51 -07:00
Geert Uytterhoeven
135739a2a9 Documentation: mailbox: mbox_chan_ops.flush() is optional
When the optional .flush() method was added to the mbox_chan structure,
the documentation was not updated.

Fixes: a8803d7421 ("mailbox: Support blocking transfers in atomic context")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <6a50a5d4f0d0da26e5cccf348550879e53792e6e.1764861174.git.geert+renesas@glider.be>
2025-12-22 15:30:31 -07:00
Soham Metha
7508b208f1 Documentation/rv: Fix dead link to monitor_synthesis.rst
The file 'da_monitor_synthesis.rst' was renamed to 'monitor_synthesis.rst' in
commit f40a7c0602
("Documentation/rv: Prepare monitor synthesis document for LTL inclusion").

Signed-off-by: Soham Metha <sohammetha01@gmail.com>
Fixes: f40a7c0602 ("Documentation/rv: Prepare monitor synthesis document for LTL inclusion")
Acked-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251204032452.9523-1-sohammetha01@gmail.com>
2025-12-22 15:30:26 -07:00
Shubham Sharma
1de54df949 Documentation: arm: keystone: update DT binding reference
Update the device tree binding reference from .txt to YAML.
Binding was converted in commit 20b3c9a403 ("dt-bindings: arm: Convert ti,keystone to DT schema")
and moved to Documentation/devicetree/bindings/arm/ti/ti,keystone.yaml.

Signed-off-by: Shubham Sharma <slopixelz@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251207195632.68681-1-slopixelz@gmail.com>
2025-12-22 15:20:05 -07:00
Addison English
faa395bcda docs: fix typo in clang-format documentation
The clang-format documentation contains a minor spelling issue where
"intended" is used instead of "indented" when describing deeply nested
code. This patch corrects the typo to improve the clarity and consistency.

Signed-off-by: Addison English <addison.englishw@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251208065136.9092-1-addison.englishw@gmail.com>
2025-12-22 15:18:57 -07:00
Mark Brown
9b7688c19c
ASoC: qcom: Constify few things in audioreach and
Merge series from Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>:

Several functions do not modify the pointed memory they receive, so
marking them as pointers to const would serve as self-explanatory code.
Also safer a bit.
2025-12-22 22:13:08 +00:00
Mark Brown
3572ad8220
ASoC: drop bogus container_of() error handling
Merge series from Johan Hovold <johan@kernel.org>:

The dev_to_sdw_dev() helper uses container_of() to return the containing
soundwire device structure of its pointer argument and will never
return NULL.
2025-12-22 22:13:03 +00:00
Steven Price
9dbbd32ecd kdoc: allow dots in inline @param names
Inline kernel-doc blocks failed to parse tags containing dots (e.g.
creator.process_name in panfrost_gem.h) because the @name regex only
matched word characters. Modify the single-line pattern to match
doc_inline_sect so it includes \. and parses the same as a multi-line
comment.

Signed-off-by: Steven Price <steven.price@arm.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251211104851.45330-1-steven.price@arm.com>
2025-12-22 15:05:22 -07:00
Andy Shevchenko
197bbebd25 docs: Update documentation to avoid mentioning of kernel.h
For several years, and still ongoing, the kernel.h is being split
to smaller and narrow headers to avoid "including everything" approach
which is bad in many ways. Since that, documentation missed a few
required updates to align with that work. Do it here.

Note, language translations are left untouched and if anybody willing
to help, please provide path(es) based on the updated English variant.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251126214709.2322314-1-andriy.shevchenko@linux.intel.com>
2025-12-22 14:59:18 -07:00
Max Nikulin
5188f6bd40 docs: admin: devices: /dev/sr<N> for SCSI CD-ROM
Don't claim that /dev/sr<N> device names for SCSI CD-ROM drives are
deprecated and don't recommend /dev/scd<N> alternate names for them.

/dev/scd<N> device names for SCSI CD-ROM drives are not in use for more
than a decade, see commit [1] that was a part of udev release 174.
Earlier, related rules were volatile, sometimes /dev/scd<N> were syminks
to /dev/sr<N>, sometimes vice versa.

Recognizing of root=/dev/scd<N> kernel command line argument was removed
in kernel 2.5.45 [2].

In the docs /dev/scd<N> became recommended names in 2.6.9 [3].
Mention of these names appeared much earlier in 1.3.22 [4].

[1] https://git.kernel.org/pub/scm/linux/hotplug/udev.git/commit/?id=d132be4d58
    2011-08-12 14:05:19 +0200 Kay Sievers.
    rules: remove legacy rules for cdrom and usb printer

[2] https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/init?h=v2.5.45&id=51924607bd
    2002-10-29 00:47:58 -0800 Alexander Viro.
    [PATCH] removal of root_dev_names[]

[3] https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/diff/Documentation/devices.txt?h=v2.6.9-rc4&id=a74e11ffeda
    2004-03-16 15:09:38 -0800 Andrew Morton:
    [PATCH] devices.txt: typos and removal of dead devices

[4] https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/tree/Documentation/devices.txt?h=v2.6.9-rc4&id=8f0ec1f9369
    1995-09-01 Linus Torvalds: Import 1.3.22

Signed-off-by: Max Nikulin <manikulin@gmail.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <f0a3e0aa-e4f9-41d3-8931-57837831d136@gmail.com>
2025-12-22 14:56:09 -07:00
Jonathan Corbet
d07e0857dc Merge branch 'mauro-vars' into docs-mw
Mauro says:

As suggested and discussed with Randy, this small series add support
for documenting variables using kernel-doc.

- patch 1: add support for the new feature;
- patch 2: extends to support DEFINE_*;
- patch 3: document two media vars;
- patch 4: fix an issue on kernel-doc.rst markups and automarkup;
- patch 5: document it;
- patch 6: better handle DEFINE_ macros when they don't have static/type;

Since version 5, I'm using "c:macro" to describe variables, as it
avoids Sphinx C domain to try parse the variable. This makes it more
flexible and easier to maintain in long term.
2025-12-22 14:52:57 -07:00
Mauro Carvalho Chehab
aaacd70fb7 docs: kernel-doc.rst: Parse DEFINE_ macros without prefixes
Currently, the logic for vars require a
	type DEFINE_foo();

where type is usually "static".

Make the logic more generic.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/linux-doc/e1dad7e4-a0ca-4be6-a33c-97b75175c12f@infradead.org/
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <be16e087cbc065fbd041fb6d6f8fa5cf0426cca5.1765894964.git.mchehab+huawei@kernel.org>
2025-12-22 14:43:25 -07:00
Mauro Carvalho Chehab
b580fa304c docs: kernel-doc.rst: document the new "var" kernel-doc markup
Add a description containing the new syntax to document
variables within kernel-doc markups.

Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <aa0e3abcd6882a62f3ab9c34033c60fca1c44604.1765894964.git.mchehab+huawei@kernel.org>
2025-12-22 14:43:25 -07:00
Mauro Carvalho Chehab
8deb5d725b docs: kernel-doc.rst: don't let automarkup mangle with consts
This document contains several words that tricks automarkup.

Ensure that all of them will be inside a ``const`` markup,
avoiding automarkup to touch them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <a6adfa3d775c1dccc9f80a7b82be003cbc0051d2.1765894964.git.mchehab+huawei@kernel.org>
2025-12-22 14:43:25 -07:00
Mauro Carvalho Chehab
bea467aa5d docs: media: v4l2-ioctl.h: document two global variables
The media kAPI has two global variables at v4l2-ioctl.h. Document
them.

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <8ebe25ff579962fec09b586f00e77fae7802985f.1765894964.git.mchehab+huawei@kernel.org>
2025-12-22 14:43:25 -07:00
Mauro Carvalho Chehab
bdd1cf8784 kernel-doc: add support to handle DEFINE_ variables
Improve the parser and output plugin to work with macros,
adding support for the common pattern of using DEFINE_*
to create variables.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <757a45100cfc493984574ff780aa9d90506eecb4.1765894964.git.mchehab+huawei@kernel.org>
2025-12-22 14:43:25 -07:00
Mauro Carvalho Chehab
1045ec382c kernel-doc: add support for handling global variables
Specially on kAPI, sometimes it is desirable to be able to
describe global variables that are part of kAPI.

Documenting vars with Sphinx is simple, as we don't need
to parse a data struct. All we need is the variable
declaration and use native C domain ::c:var: to format it
for us.

Add support for it.

Link: https://lore.kernel.org/linux-doc/491c3022-cef8-4860-a945-c9c4a3b63c09@infradead.org/T/#m947c25d95cb1d96a394410ab1131dc8e9e5013f1
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <fa7d1c61a8de9150f71b318382f1507d3b13848d.1765894964.git.mchehab+huawei@kernel.org>
2025-12-22 14:43:25 -07:00
Thorsten Blum
82e87387f6 Documentation: kernel-hacking: Remove comma
The comma is wrong, remove it.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251219171827.44015-2-thorsten.blum@linux.dev>
2025-12-22 14:40:24 -07:00
Chen Pei
f089d9b2c2 docs: kbuild: Fix typos in makefiles.rst
The correct command to generate header files is
make headers_install.

Signed-off-by: Chen Pei <cp0613@linux.alibaba.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20251220125434.2430-1-cp0613@linux.alibaba.com>
2025-12-22 14:39:44 -07:00
David Gow
c31f4aa8fe kunit: Enforce task execution in {soft,hard}irq contexts
The kunit_run_irq_test() helper allows a function to be run in hardirq
and softirq contexts (in addition to the task context). It does this by
running the user-provided function concurrently in the three contexts,
until either a timeout has expired or a number of iterations have
completed in the normal task context.

However, on setups where the initialisation of the hardirq and softirq
contexts (or, indeed, the scheduling of those tasks) is significantly
slower than the function execution, it's possible for that number of
iterations to be exceeded before any runs in irq contexts actually
occur. This occurs with the polyval.test_polyval_preparekey_in_irqs
test, which runs 20000 iterations of the relatively fast preparekey
function, and therefore fails often under many UML, 32-bit arm, m68k and
other environments.

Instead, ensure that the max_iterations limit counts executions in all
three contexts, and requires at least one of each. This will cause the
test to continue iterating until at least the irq contexts have been
tested, or the 1s wall-clock limit has been exceeded. This causes the
test to pass in all of my environments.

In so doing, we also update the task counters to atomic ints, to better
match both the 'int' max_iterations input, and to ensure they are
correctly updated across contexts.

Finally, we also fix a few potential assertion messages to be
less-specific to the original crypto usecases.

Fixes: 950a81224e ("lib/crypto: tests: Add hash-test-template.h and gen-hash-testvecs.py")
Signed-off-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/r/20251219085259.1163048-1-davidgow@google.com
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-12-22 12:20:08 -08:00
Mark Brown
e9af75df38
SDCA Jack Fixups
Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>:

Some fixups to the jack handling, adding some necessary hooks to connect
things with the machine driver. I have split these out from the system
suspend chain as that has been generating a fair amount of discussion
and getting these 3 merged is far more important to get basic
functionality working smoothly. I will do a spin of the system suspend
stuff soon, if either no new comments pop up, or we reach some consensus
on how to proceed.
2025-12-22 19:41:23 +00:00
Mark Brown
0bd4b0f583
ASoC / soc/qcom: Constify APR/GPR callback response
Merge series from Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>:

This constifies the response data used for APR/GPR callbacks.
2025-12-22 19:41:18 +00:00
Daniele Ceraolo Spurio
f474911fe1 drm/xe/pf: Add debugfs to set EQ and PT for scheduler groups
Debugfs files are added to allow a user to provide a comma-separated list
of values to assign to each group for each VF.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20251218223846.1146344-26-daniele.ceraolospurio@intel.com
2025-12-22 10:22:18 -08:00
Daniele Ceraolo Spurio
be4518128a drm/xe/pf: Add functions to set preempt timeouts for each group
The KLV to set the preemption timeout for each groups works the exact
same way as the one for the exec quantums, so we add similar functions.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20251218223846.1146344-25-daniele.ceraolospurio@intel.com
2025-12-22 10:22:16 -08:00