Merge ACPI processor driver changes for 6.6-rc1:
- Support obtaining physical CPU ID from MADT on LoongArch (Bibo Mao).
- Convert ACPI CPU initialization to using _OSC instead of _PDC that
has been depreceted since 2018 and dropped from the specification in
ACPI 6.5 (Michal Wilczynski, Rafael Wysocki).
* acpi-processor:
ACPI: processor: LoongArch: Get physical ID from MADT
ACPI: processor: Refine messages in acpi_early_processor_control_setup()
ACPI: processor: Remove acpi_hwp_native_thermal_lvt_osc()
ACPI: processor: Use _OSC to convey OSPM processor support information
ACPI: processor: Introduce acpi_processor_osc()
ACPI: processor: Set CAP_SMP_T_SWCOORD in arch_acpi_set_proc_cap_bits()
ACPI: processor: Clear C_C2C3_FFH and C_C1_FFH in arch_acpi_set_proc_cap_bits()
ACPI: processor: Rename ACPI_PDC symbols
ACPI: processor: Refactor arch_acpi_set_pdc_bits()
ACPI: processor: Move processor_physically_present() to acpi_processor.c
ACPI: processor: Move MWAIT quirk out of acpi_processor.c
Merge changes related to the ACPI bus type and ACPI backlight driver
changes for 6.6-rc1:
- Introduce new wrappers for ACPICA notify handler install/remove and
convert multiple drivers to using their own Notify() handlers instead
of the ACPI bus type .notify() slated for removal (Michal Wilczynski).
- Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2 (Hans
de Goede).
- Put ACPI video and its child devices explicitly into D0 on boot to
avoid platform firmware confusion (Kai-Heng Feng).
- Add backlight=native DMI quirk for Lenovo Ideapad Z470 (Jiri Slaby).
* acpi-bus:
ACPI: thermal: Install Notify() handler directly
ACPI: NFIT: Remove unnecessary .remove callback
ACPI: NFIT: Install Notify() handler directly
ACPI: HED: Install Notify() handler directly
ACPI: battery: Install Notify() handler directly
ACPI: video: Install Notify() handler directly
ACPI: AC: Install Notify() handler directly
ACPI: bus: Set driver_data to NULL every time .add() fails
ACPI: bus: Introduce wrappers for ACPICA notify handler install/remove
* acpi-video:
ACPI: video: Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2
ACPI: video: Put ACPI video and its child devices into D0 on boot
ACPI: video: Add backlight=native DMI quirk for Lenovo Ideapad Z470
Merge ACPICA material for 6.6-rc1.
This includes some fixes, cleanups and new material, mostly related to
parsing tables.
Specifics:
- Suppress a GCC 12 dangling-pointer warning (Philip Prindeville).
- Reformat the ACPI_STATE_COMMON macro and its users (George Guo).
- Replace the ternary operator with ACPI_MIN() (Jiangshan Yi).
- Add support for _DSC as per ACPI 6.5 (Saket Dumbre).
- Remove a duplicate macro from zephyr header (Najumon B.A).
- Add data structures for GED and _EVT tracking (Jose Marinho).
- Fix misspelled CDAT DSMAS define (Dave Jiang).
- Simplify an error message in acpi_ds_result_push() (Christophe
Jaillet).
- Add a struct size macro related to SRAT (Dave Jiang).
- Add AML_NO_OPERAND_RESOLVE flag to Timer (Abhishek Mainkar).
- Add support for RISC-V external interrupt controllers in MADT (Sunil
V L).
- Add RHCT flags, CMO and MMU nodes (Sunil V L).
- Change ACPICA version to 20230628 (Bob Moore).
* acpica:
ACPICA: Update version to 20230628
ACPICA: RHCT: Add flags, CMO and MMU nodes
ACPICA: MADT: Add RISC-V external interrupt controllers
ACPICA: Add AML_NO_OPERAND_RESOLVE flag to Timer
ACPICA: Add a define for size of struct acpi_srat_generic_affinity device_handle
ACPICA: Slightly simplify an error message in acpi_ds_result_push()
ACPICA: Fix misspelled CDAT DSMAS define
ACPICA: Add interrupt command to acpiexec
ACPICA: Detect GED device and keep track of _EVT
ACPICA: fix for conflict macro definition on zephyr interface
ACPICA: Add support for _DSC as per ACPI 6.5
ACPICA: exserial.c: replace ternary operator with ACPI_MIN()
ACPICA: Modify ACPI_STATE_COMMON
ACPICA: Fix GCC 12 dangling-pointer warning
Pull RISC-V fixes from Palmer Dabbelt:
"This is obviously not ideal, particularly for something this late in
the cycle.
Unfortunately we found some uABI issues in the vector support while
reviewing the GDB port, which has triggered a revert -- probably a
good sign we should have reviewed GDB before merging this, I guess I
just dropped the ball because I was so worried about the context
extension and libc suff I forgot. Hence the late revert.
There's some risk here as we're still exposing the vector context for
signal handlers, but changing that would have meant reverting all of
the vector support. The issues we've found so far have been fixed
already and they weren't absolute showstoppers, so we're essentially
just playing it safe by holding ptrace support for another release (or
until we get through a proper userspace code review).
Summary:
- The vector ucontext extension has been extended with vlenb
- The vector registers ELF core dump note type has been changed to
avoid aliasing with the CSR type used in embedded systems
- Support for accessing vector registers via ptrace() has been
reverted
- Another build fix for the ISA spec changes around Zifencei/Zicsr
that manifests on some systems built with binutils-2.37 and
gcc-11.2"
* tag 'riscv-for-linus-6.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Fix build errors using binutils2.37 toolchains
RISC-V: vector: export VLENB csr in __sc_riscv_v_state
RISC-V: Remove ptrace support for vectors
An earlier patch in the series ensures that the underlying memory of
nodes with bpf_refcount - which can have multiple owners - is not reused
until RCU grace period has elapsed. This prevents
use-after-free with non-owning references that may point to
recently-freed memory. While RCU read lock is held, it's safe to
dereference such a non-owning ref, as by definition RCU GP couldn't have
elapsed and therefore underlying memory couldn't have been reused.
From the perspective of verifier "trustedness" non-owning refs to
refcounted nodes are now trusted only in RCU CS and therefore should no
longer pass is_trusted_reg, but rather is_rcu_reg. Let's mark them
MEM_RCU in order to reflect this new state.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230821193311.3290257-6-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Recent discussions around default kptr "trustedness" led to changes such
as commit 6fcd486b3a ("bpf: Refactor RCU enforcement in the
verifier."). One of the conclusions of those discussions, as expressed
in code and comments in that patch, is that we'd like to move away from
'raw' PTR_TO_BTF_ID without some type flag or other register state
indicating trustedness. Although PTR_TRUSTED and PTR_UNTRUSTED flags mark
this state explicitly, the verifier currently considers trustedness
implied by other register state. For example, owning refs to graph
collection nodes must have a nonzero ref_obj_id, so they pass the
is_trusted_reg check despite having no explicit PTR_{UN}TRUSTED flag.
This patch makes trustedness of non-owning refs to graph collection
nodes explicit as well.
By definition, non-owning refs are currently trusted. Although the ref
has no control over pointee lifetime, due to non-owning ref clobbering
rules (see invalidate_non_owning_refs) dereferencing a non-owning ref is
safe in the critical section controlled by bpf_spin_lock associated with
its owning collection.
Note that the previous statement does not hold true for nodes with shared
ownership due to the use-after-free issue that this series is
addressing. True shared ownership was disabled by commit 7deca5eae8
("bpf: Disable bpf_refcount_acquire kfunc calls until race conditions are fixed"),
though, so the statement holds for now. Further patches in the series will change
the trustedness state of non-owning refs before re-enabling
bpf_refcount_acquire.
Let's add NON_OWN_REF type flag to BPF_REG_TRUSTED_MODIFIERS such that a
non-owning ref reg state would pass is_trusted_reg check. Somewhat
surprisingly, this doesn't result in any change to user-visible
functionality elsewhere in the verifier: graph collection nodes are all
marked MEM_ALLOC, which tends to be handled in separate codepaths from
"raw" PTR_TO_BTF_ID. Regardless, let's be explicit here and document the
current state of things before changing it elsewhere in the series.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230821193311.3290257-3-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull drm fixes from Dave Airlie:
"A bit bigger than I'd care for, but it's mostly a single vmwgfx fix
and a fix for an i915 hotplug probing. Otherwise misc i915, bridge,
panfrost and dma-buf fixes.
core:
- add a HPD poll helper
i915:
- fix regression in i915 polling
- fix docs build warning
- fix DG2 idle power consumption
bridge:
- samsung-dsim: init fix
panfrost:
- fix speed binning issue
dma-buf:
- fix recursive lock in fence signal
vmwgfx:
- fix shader stage validation
- fix NULL ptr derefs in gem put"
* tag 'drm-fixes-2023-08-25' of git://anongit.freedesktop.org/drm/drm:
drm/i915: Fix HPD polling, reenabling the output poll work as needed
drm: Add an HPD poll helper to reschedule the poll work
drm/vmwgfx: Fix possible invalid drm gem put calls
drm/vmwgfx: Fix shader stage validation
dma-buf/sw_sync: Avoid recursive lock during fence signal
drm/i915: fix Sphinx indentation warning
drm/i915/dgfx: Enable d3cold at s2idle
drm/display/dp: Fix the DP DSC Receiver cap size
drm/panfrost: Skip speed binning on EOPNOTSUPP
drm: bridge: samsung-dsim: Fix init during host transfer
Allocations and frees are globally serialized on the pcpu lock (and the
CPU hotplug lock if enabled, which is the case on Debian).
At least one frequent consumer allocates 4 back-to-back counters (and
frees them in the same manner), exacerbating the problem.
While this does not fully remedy scalability issues, it is a step
towards that goal and provides immediate relief.
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Reviewed-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com>
Link: https://lore.kernel.org/r/20230823050609.2228718-2-mjguzik@gmail.com
[Dennis: reflowed a few lines]
Signed-off-by: Dennis Zhou <dennis@kernel.org>
intel-pinctrl for v6.6-1
* New library driver for Intel MID to deduplicate code (Raag Jadav)
* Reuse common functions from pinctrl-intel to reduce the code (Raag Jadav)
* Move most of the exported functions to the PINCTRL_INTEL namespace
* Make use of pm_ptr() in Bay Trail and Lynxpoint drivers
* Introduce DEFINE_NOIRQ_DEV_PM_OPS() helper and use it in a few drivers
* Consolidata ACPI dependency in Kconfig (Raag Jadav)
* Fix address_space_handler() argument in Cherryview driver (Raag Jadav)
* Optinmize byt_pin_config_set() to avoid IO in error cases (Raag Jadav)
The following is an automated git shortlog grouped by driver:
at91:
- Switch to use DEFINE_NOIRQ_DEV_PM_OPS() helper
baytrail:
- Make use of pm_ptr()
- reuse common functions from pinctrl-intel
- consolidate common mask operation
cherryview:
- fix address_space_handler() argument
- Switch to use DEFINE_NOIRQ_DEV_PM_OPS() helper
- reuse common functions from pinctrl-intel
intel:
- consolidate ACPI dependency
- Switch to use exported namespace
- export common pinctrl functions
lynxpoint:
- Make use of pm_ptr()
- reuse common functions from pinctrl-intel
Merge patch series:
- Merge patch series "Introduce Intel Tangier pinctrl driver"
- Merge patch series "Reuse common functions from pinctrl-intel"
merrifield:
- Adapt to Intel Tangier driver
moorefield:
- Adapt to Intel Tangier driver
mvebu:
- Switch to use DEFINE_NOIRQ_DEV_PM_OPS() helper
pm:
- Introduce DEFINE_NOIRQ_DEV_PM_OPS() helper
renesas:
- Switch to use DEFINE_NOIRQ_DEV_PM_OPS() helper
tangier:
- Introduce Intel Tangier driver
tegra:
- Switch to use DEFINE_NOIRQ_DEV_PM_OPS() helper
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
To support the need for host specific tuning for SD high-speed mode, let's
add two new optional callbacks, ->prepare|execute_sd_hs_tuning() and let's
call them when switching into the SD high-speed mode.
Note that, during the tuning process it's also needed for host drivers to
send commands to the SD card to verify that the tuning process succeeds.
Therefore, let's also share the corresponding functions from the core to
allow this.
Signed-off-by: Wenchao Chen <wenchao.chen@unisoc.com>
Link: https://lore.kernel.org/r/20230825091743.15613-2-wenchao.chen@unisoc.com
[Ulf: Dropped unnecessary function declarations and updated the commit msg]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
The goal is to support a bpf_redirect() from an ethernet device (ingress)
to a ppp device (egress).
The l2 header is added automatically by the ppp driver, thus the ethernet
header should be removed.
CC: stable@vger.kernel.org
Fixes: 27b29f6305 ("bpf: add bpf_redirect() helper")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Tested-by: Siwar Zitouni <siwar.zitouni@6wind.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
According to chapter 6 of DesignWare Cores Ethernet PCS (version 3.20a)
and custom design manual, add a configuration flow for switching interface
mode.
If the interface changes, the following setting is required:
1. wait VR_XS_PCS_DIG_STS bit(4, 2) [PSEQ_STATE] = 100b (Power-Good)
2. write SR_XS_PCS_CTRL2 to select various PCS type
3. write SR_PMA_CTRL1 and/or SR_XS_PCS_CTRL1 for link speed
4. program PMA registers
5. write VR_XS_PCS_DIG_CTRL1 bit(15) [VR_RST] = 1b (Vendor-Specific
Soft Reset)
6. wait for VR_XS_PCS_DIG_CTRL1 bit(15) [VR_RST] to get cleared
Only 10GBASE-R/SGMII/1000BASE-X modes are planned for the current Wangxun
devices. And there is a quirk for Wangxun devices to switch mode although
the interface in phylink state has not changed, since PCS will change to
default 10GBASE-R when the ethernet driver(txgbe) do LAN reset.
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since Wangxun 10Gb NICs require some special configuration on the IP of
Synopsys Designware XPCS, introduce dev_flag for different vendors. Read
OUI from device identifier registers, to detect Wangxun devices.
And xpcs_soft_reset() is skipped to avoid the reset of device identifier
registers.
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull tracing fixes from Steven Rostedt:
- Fix ring buffer being permanently disabled due to missed
record_disabled()
Changing the trace cpu mask will disable the ring buffers for the
CPUs no longer in the mask. But it fails to update the snapshot
buffer. If a snapshot takes place, the accounting for the ring buffer
being disabled is corrupted and this can lead to the ring buffer
being permanently disabled.
- Add test case for snapshot and cpu mask working together
- Fix memleak by the function graph tracer not getting closed properly.
The iterator is used to read the ring buffer. When it opens, it calls
the open function of a tracer, and when it is closed, it calls the
close iteration. While a trace is being read, it is still possible to
change the tracer.
If this happens between the function graph tracer and the wakeup
tracer (which uses function graph tracing), the tracers are not
closed properly during when the iterator sees the switch, and the
wakeup function did not initialize its private pointer to NULL, which
is used to know if the function graph tracer was the last tracer. It
could be fooled in thinking it is, but then on exit it does not call
the close function of the function graph tracer to clean up its data.
- Fix synthetic events on big endian machines, by introducing a union
that does the conversions properly.
- Fix synthetic events from printing out the number of elements in the
stacktrace when it shouldn't.
- Fix synthetic events stacktrace to not print a bogus value at the
end.
- Introduce a pipe_cpumask that prevents the trace_pipe files from
being opened by more than one task (file descriptor).
There was a race found where if splice is called, the iter->ent could
become stale and events could be missed. There's no point reading a
producer/consumer file by more than one task as they will corrupt
each other anyway. Add a cpumask that keeps track of the per_cpu
trace_pipe files as well as the global trace_pipe file that prevents
more than one open of a trace_pipe file that represents the same ring
buffer. This prevents the race from happening.
- Fix ftrace samples for arm64 to work with older compilers.
* tag 'trace-v6.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
samples: ftrace: Replace bti assembly with hint for older compiler
tracing: Introduce pipe_cpumask to avoid race on trace_pipes
tracing: Fix memleak due to race between current_tracer and trace
tracing/synthetic: Allocate one additional element for size
tracing/synthetic: Skip first entry for stack traces
tracing/synthetic: Use union instead of casts
selftests/ftrace: Add a basic testcase for snapshot
tracing: Fix cpu buffers unavailable due to 'record_disabled' missed
The raid_component_add() function was added to the kernel tree via patch
"[SCSI] embryonic RAID class" (2005). Remove this function since it never
has had any callers in the Linux kernel. And also raid_component_release()
is only used in raid_component_add(), so it is also removed.
Signed-off-by: Zhu Wang <wangzhu9@huawei.com>
Link: https://lore.kernel.org/r/20230822015254.184270-1-wangzhu9@huawei.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Fixes: 04b5b5cb01 ("scsi: core: Fix possible memory leak if device_add() fails")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Igor Pylypiv <ipylypiv@google.com> says:
This patch series plumbs libata's request for a result taskfile
(ATA_QCFLAG_RESULT_TF) through libsas to pm80xx LLDD. Other libsas LLDDs
can start using the newly added return_fis_on_success as well, if needed.
For Command Duration Limits policy 0xD (command completes without an
error) libata needs FIS in order to detect the ATA_SENSE bit and read
the Sense Data for Successful NCQ Commands log (0Fh). pm80xx HBAs do
not return FIS on success by default, hence, the driver is updated to
set the RETFIS bit (Return FIS on good completion) when requested by
libsas.
Link: https://lore.kernel.org/r/20230819213040.1101044-1-ipylypiv@google.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In ms_hyperv_init_platform(), do not distinguish between a SNP VM with
the paravisor and a SNP VM without the paravisor.
Replace hv_isolation_type_en_snp() with
!ms_hyperv.paravisor_present && hv_isolation_type_snp().
The hv_isolation_type_en_snp() in drivers/hv/hv.c and
drivers/hv/hv_common.c can be changed to hv_isolation_type_snp() since
we know !ms_hyperv.paravisor_present is true there.
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230824080712.30327-10-decui@microsoft.com
No logic change to SNP/VBS guests.
hv_isolation_type_tdx() will be used to instruct a TDX guest on Hyper-V to
do some TDX-specific operations, e.g. for a fully enlightened TDX guest
(i.e. without the paravisor), hv_do_hypercall() should use
__tdx_hypercall() and such a guest on Hyper-V should handle the Hyper-V
Event/Message/Monitor pages specially.
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Tianyu Lan <tiala@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230824080712.30327-2-decui@microsoft.com
Add the comment to explain that while_each_thread(g,t) is not rcu-safe
unless g is stable (e.g. current). Even if g is a group leader and thus
can't exit before t, t or another sub-thread can exec and remove g from
the thread_group list.
The only lockless user of while_each_thread() is first_tid() and it is
fine in that it can't loop forever, yet for_each_thread() looks better and
I am going to change while_each_thread/next_thread.
Link: https://lkml.kernel.org/r/20230823170806.GA11724@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The hotplug support for kexec_load() requires changes to the userspace
kexec-tools and a little extra help from the kernel.
Given a kdump capture kernel loaded via kexec_load(), and a subsequent
hotplug event, the crash hotplug handler finds the elfcorehdr and rewrites
it to reflect the hotplug change. That is the desired outcome, however,
at kernel panic time, the purgatory integrity check fails (because the
elfcorehdr changed), and the capture kernel does not boot and no vmcore is
generated.
Therefore, the userspace kexec-tools/kexec must indicate to the kernel
that the elfcorehdr can be modified (because the kexec excluded the
elfcorehdr from the digest, and sized the elfcorehdr memory buffer
appropriately).
To facilitate hotplug support with kexec_load():
- a new kexec flag KEXEC_UPATE_ELFCOREHDR indicates that it is
safe for the kernel to modify the kexec_load()'d elfcorehdr
- the /sys/kernel/crash_elfcorehdr_size node communicates the
preferred size of the elfcorehdr memory buffer
- The sysfs crash_hotplug nodes (ie.
/sys/devices/system/[cpu|memory]/crash_hotplug) dynamically
take into account kexec_file_load() vs kexec_load() and
KEXEC_UPDATE_ELFCOREHDR.
This is critical so that the udev rule processing of crash_hotplug
is all that is needed to determine if the userspace unload-then-load
of the kdump image is to be skipped, or not. The proposed udev
rule change looks like:
# The kernel updates the crash elfcorehdr for CPU and memory changes
SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
The table below indicates the behavior of kexec_load()'d kdump image
updates (with the new udev crash_hotplug rule in place):
Kernel |Kexec
-------+-----+----
Old |Old |New
| a | a
-------+-----+----
New | a | b
-------+-----+----
where kexec 'old' and 'new' delineate kexec-tools has the needed
modifications for the crash hotplug feature, and kernel 'old' and 'new'
delineate the kernel supports this crash hotplug feature.
Behavior 'a' indicates the unload-then-reload of the entire kdump image.
For the kexec 'old' column, the unload-then-reload occurs due to the
missing flag KEXEC_UPDATE_ELFCOREHDR. An 'old' kernel (with 'new' kexec)
does not present the crash_hotplug sysfs node, which leads to the
unload-then-reload of the kdump image.
Behavior 'b' indicates the desired optimized behavior of the kernel
directly modifying the elfcorehdr and avoiding the unload-then-reload of
the kdump image.
If the udev rule is not updated with crash_hotplug node check, then no
matter any combination of kernel or kexec is new or old, the kdump image
continues to be unload-then-reload on hotplug changes.
To fully support crash hotplug feature, there needs to be a rollout of
kernel, kexec-tools and udev rule changes. However, the order of the
rollout of these pieces does not matter; kexec_load()'d kdump images still
function for hotplug as-is.
Link: https://lkml.kernel.org/r/20230814214446.6659-7-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Suggested-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Akhil Raj <lf32.dev@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Introduce the crash_hotplug attribute for memory and CPUs for use by
userspace. These attributes directly facilitate the udev rule for
managing userspace re-loading of the crash kernel upon hot un/plug
changes.
For memory, expose the crash_hotplug attribute to the
/sys/devices/system/memory directory. For example:
# udevadm info --attribute-walk /sys/devices/system/memory/memory81
looking at device '/devices/system/memory/memory81':
KERNEL=="memory81"
SUBSYSTEM=="memory"
DRIVER==""
ATTR{online}=="1"
ATTR{phys_device}=="0"
ATTR{phys_index}=="00000051"
ATTR{removable}=="1"
ATTR{state}=="online"
ATTR{valid_zones}=="Movable"
looking at parent device '/devices/system/memory':
KERNELS=="memory"
SUBSYSTEMS==""
DRIVERS==""
ATTRS{auto_online_blocks}=="offline"
ATTRS{block_size_bytes}=="8000000"
ATTRS{crash_hotplug}=="1"
For CPUs, expose the crash_hotplug attribute to the
/sys/devices/system/cpu directory. For example:
# udevadm info --attribute-walk /sys/devices/system/cpu/cpu0
looking at device '/devices/system/cpu/cpu0':
KERNEL=="cpu0"
SUBSYSTEM=="cpu"
DRIVER=="processor"
ATTR{crash_notes}=="277c38600"
ATTR{crash_notes_size}=="368"
ATTR{online}=="1"
looking at parent device '/devices/system/cpu':
KERNELS=="cpu"
SUBSYSTEMS==""
DRIVERS==""
ATTRS{crash_hotplug}=="1"
ATTRS{isolated}==""
ATTRS{kernel_max}=="8191"
ATTRS{nohz_full}==" (null)"
ATTRS{offline}=="4-7"
ATTRS{online}=="0-3"
ATTRS{possible}=="0-7"
ATTRS{present}=="0-3"
With these sysfs attributes in place, it is possible to efficiently
instruct the udev rule to skip crash kernel reloading for kernels
configured with crash hotplug support.
For example, the following is the proposed udev rule change for RHEL
system 98-kexec.rules (as the first lines of the rule file):
# The kernel updates the crash elfcorehdr for CPU and memory changes
SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
When examined in the context of 98-kexec.rules, the above rules test if
crash_hotplug is set, and if so, the userspace initiated
unload-then-reload of the crash kernel is skipped.
CPU and memory checks are separated in accordance with CONFIG_HOTPLUG_CPU
and CONFIG_MEMORY_HOTPLUG kernel config options. If an architecture
supports, for example, memory hotplug but not CPU hotplug, then the
/sys/devices/system/memory/crash_hotplug attribute file is present, but
the /sys/devices/system/cpu/crash_hotplug attribute file will NOT be
present. Thus the udev rule skips userspace processing of memory hot
un/plug events, but the udev rule will evaluate false for CPU events, thus
allowing userspace to process CPU hot un/plug events (ie the
unload-then-reload of the kdump capture kernel).
Link: https://lkml.kernel.org/r/20230814214446.6659-5-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Akhil Raj <lf32.dev@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
To support crash hotplug, a mechanism is needed to update the crash
elfcorehdr upon CPU or memory changes (eg. hot un/plug or off/ onlining).
The crash elfcorehdr describes the CPUs and memory to be written into the
vmcore.
To track CPU changes, callbacks are registered with the cpuhp mechanism
via cpuhp_setup_state_nocalls(CPUHP_BP_PREPARE_DYN). The crash hotplug
elfcorehdr update has no explicit ordering requirement (relative to other
cpuhp states), so meets the criteria for utilizing CPUHP_BP_PREPARE_DYN.
CPUHP_BP_PREPARE_DYN is a dynamic state and avoids the need to introduce a
new state for crash hotplug. Also, CPUHP_BP_PREPARE_DYN is the last state
in the PREPARE group, just prior to the STARTING group, which is very
close to the CPU starting up in a plug/online situation, or stopping in a
unplug/ offline situation. This minimizes the window of time during an
actual plug/online or unplug/offline situation in which the elfcorehdr
would be inaccurate. Note that for a CPU being unplugged or offlined, the
CPU will still be present in the list of CPUs generated by
crash_prepare_elf64_headers(). However, there is no need to explicitly
omit the CPU, see justification in 'crash: change
crash_prepare_elf64_headers() to for_each_possible_cpu()'.
To track memory changes, a notifier is registered to capture the memblock
MEM_ONLINE and MEM_OFFLINE events via register_memory_notifier().
The CPU callbacks and memory notifiers invoke crash_handle_hotplug_event()
which performs needed tasks and then dispatches the event to the
architecture specific arch_crash_handle_hotplug_event() to update the
elfcorehdr with the current state of CPUs and memory. During the process,
the kexec_lock is held.
Link: https://lkml.kernel.org/r/20230814214446.6659-3-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Akhil Raj <lf32.dev@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "crash: Kernel handling of CPU and memory hot un/plug", v28.
Once the kdump service is loaded, if changes to CPUs or memory occur,
either by hot un/plug or off/onlining, the crash elfcorehdr must also be
updated.
The elfcorehdr describes to kdump the CPUs and memory in the system, and
any inaccuracies can result in a vmcore with missing CPU context or memory
regions.
The current solution utilizes udev to initiate an unload-then-reload of
the kdump image (eg. kernel, initrd, boot_params, purgatory and
elfcorehdr) by the userspace kexec utility. In the original post I
outlined the significant performance problems related to offloading this
activity to userspace.
This patchset introduces a generic crash handler that registers with the
CPU and memory notifiers. Upon CPU or memory changes, from either hot
un/plug or off/onlining, this generic handler is invoked and performs
important housekeeping, for example obtaining the appropriate lock, and
then invokes an architecture specific handler to do the appropriate
elfcorehdr update.
Note the description in patch 'crash: change crash_prepare_elf64_headers()
to for_each_possible_cpu()' and 'x86/crash: optimize CPU changes' that
enables further optimizations related to CPU plug/unplug/online/offline
performance of elfcorehdr updates.
In the case of x86_64, the arch specific handler generates a new
elfcorehdr, and overwrites the old one in memory; thus no involvement with
userspace needed.
To realize the benefits/test this patchset, one must make a couple
of minor changes to userspace:
- Prevent udev from updating kdump crash kernel on hot un/plug changes.
Add the following as the first lines to the RHEL udev rule file
/usr/lib/udev/rules.d/98-kexec.rules:
# The kernel updates the crash elfcorehdr for CPU and memory changes
SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
With this changeset applied, the two rules evaluate to false for
CPU and memory change events and thus skip the userspace
unload-then-reload of kdump.
- Change to the kexec_file_load for loading the kdump kernel:
Eg. on RHEL: in /usr/bin/kdumpctl, change to:
standard_kexec_args="-p -d -s"
which adds the -s to select kexec_file_load() syscall.
This kernel patchset also supports kexec_load() with a modified kexec
userspace utility. A working changeset to the kexec userspace utility is
posted to the kexec-tools mailing list here:
http://lists.infradead.org/pipermail/kexec/2023-May/027049.html
To use the kexec-tools patch, apply, build and install kexec-tools, then
change the kdumpctl's standard_kexec_args to replace the -s with
--hotplug. The removal of -s reverts to the kexec_load syscall and the
addition of --hotplug invokes the changes put forth in the kexec-tools
patch.
This patch (of 8):
The crash hotplug support leans on the work for the kexec_file_load()
syscall. To also support the kexec_load() syscall, a few bits of code
need to be move outside of CONFIG_KEXEC_FILE. As such, these bits are
moved out of kexec_file.c and into a common location crash_core.c.
In addition, struct crash_mem and crash_notes were moved to new locales so
that PROC_KCORE, which sets CRASH_CORE alone, builds correctly.
No functionality change intended.
Link: https://lkml.kernel.org/r/20230814214446.6659-1-eric.devolder@oracle.com
Link: https://lkml.kernel.org/r/20230814214446.6659-2-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Akhil Raj <lf32.dev@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Weißschuh <linux@weissschuh.net>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove the unnecessary encoding of page order into an enum and pass the
page order directly. That lets us get rid of pe_order().
The switch constructs have to be changed to if/else constructs to prevent
GCC from warning on builds with 3-level page tables where PMD_ORDER and
PUD_ORDER have the same value.
If you are looking at this commit because your driver stopped compiling,
look at the previous commit as well and audit your driver to be sure it
doesn't depend on mmap_lock being held in its ->huge_fault method.
[willy@infradead.org: use "order %u" to match the (non dev_t) style]
Link: https://lkml.kernel.org/r/ZOUYekbtTv+n8hYf@casper.infradead.org
Link: https://lkml.kernel.org/r/20230818202335.2739663-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Change calling convention for ->huge_fault", v2.
There are two unrelated changes to the calling convention for
->huge_fault. I've bundled them together to help people notice the
change. The first is to improve scalability of DAX page faults by
allowing them to be handled under the VMA lock. The second is to remove
enum page_entry_size since it's really unnecessary. The changelogs and
documentation updates hopefully work to that end.
This patch (of 3):
Allow this to be used in generic code. Also add PUD_ORDER.
Link: https://lkml.kernel.org/r/20230818202335.2739663-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20230818202335.2739663-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This is the folio equivalent of page_mapping_file(), but rename it to make
it clear that it's very different from page_file_mapping().
Theoretically, there's nothing flush-only about it, but there are no other
users today, and I doubt there will be; it's almost always more useful to
know the swapfile's mapping or the swapcache's mapping.
Link: https://lkml.kernel.org/r/20230802151406.3735276-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "New page table range API", v6.
This patchset changes the API used by the MM to set up page table entries.
The four APIs are:
set_ptes(mm, addr, ptep, pte, nr)
update_mmu_cache_range(vma, addr, ptep, nr)
flush_dcache_folio(folio)
flush_icache_pages(vma, page, nr)
flush_dcache_folio() isn't technically new, but no architecture
implemented it, so I've done that for them. The old APIs remain around
but are mostly implemented by calling the new interfaces.
The new APIs are based around setting up N page table entries at once.
The N entries belong to the same PMD, the same folio and the same VMA, so
ptep++ is a legitimate operation, and locking is taken care of for you.
Some architectures can do a better job of it than just a loop, but I have
hesitated to make too deep a change to architectures I don't understand
well.
One thing I have changed in every architecture is that PG_arch_1 is now a
per-folio bit instead of a per-page bit when used for dcache clean/dirty
tracking. This was something that would have to happen eventually, and it
makes sense to do it now rather than iterate over every page involved in a
cache flush and figure out if it needs to happen.
The point of all this is better performance, and Fengwei Yin has measured
improvement on x86. I suspect you'll see improvement on your architecture
too. Try the new will-it-scale test mentioned here:
https://lore.kernel.org/linux-mm/20230206140639.538867-5-fengwei.yin@intel.com/
You'll need to run it on an XFS filesystem and have
CONFIG_TRANSPARENT_HUGEPAGE set.
This patchset is the basis for much of the anonymous large folio work
being done by Ryan, so it's received quite a lot of testing over the last
few months.
This patch (of 38):
Determine if a value lies within a range more efficiently (subtraction +
comparison vs two comparisons and an AND). It also has useful (under some
circumstances) behaviour if the range exceeds the maximum value of the
type. Convert all the conflicting definitions of in_range() within the
kernel; some can use the generic definition while others need their own
definition.
Link: https://lkml.kernel.org/r/20230802151406.3735276-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20230802151406.3735276-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently, memcg uses rstat to maintain aggregated hierarchical stats.
Counters are maintained for hierarchical stats at each memcg. Rstat
tracks which cgroups have updates on which cpus to keep those counters
fresh on the read-side.
Non-hierarchical stats are currently not covered by rstat. Their per-cpu
counters are summed up on every read, which is expensive. The original
implementation did the same. At some point before rstat, non-hierarchical
aggregated counters were introduced by commit a983b5ebee ("mm:
memcontrol: fix excessive complexity in memory.stat reporting"). However,
those counters were updated on the performance critical write-side, which
caused regressions, so they were later removed by commit 815744d751
("mm: memcontrol: don't batch updates of local VM stats and events"). See
[1] for more detailed history.
Kernel versions in between a983b5ebee & 815744d751 (a year and a half)
enjoyed cheap reads of non-hierarchical stats, specifically on cgroup v1.
When moving to more recent kernels, a performance regression for reading
non-hierarchical stats is observed.
Now that we have rstat, we know exactly which percpu counters have updates
for each stat. We can maintain non-hierarchical counters again, making
reads much more efficient, without affecting the performance critical
write-side. Hence, add non-hierarchical (i.e local) counters for the
stats, and extend rstat flushing to keep those up-to-date.
A caveat is that we now need a stats flush before reading
local/non-hierarchical stats through {memcg/lruvec}_page_state_local() or
memcg_events_local(), where we previously only needed a flush to read
hierarchical stats. Most contexts reading non-hierarchical stats are
already doing a flush, add a flush to the only missing context in
count_shadow_nodes().
With this patch, reading memory.stat from 1000 memcgs is 3x faster on a
machine with 256 cpus on cgroup v1:
# for i in $(seq 1000); do mkdir /sys/fs/cgroup/memory/cg$i; done
# time cat /sys/fs/cgroup/memory/cg*/memory.stat > /dev/null
real 0m0.125s
user 0m0.005s
sys 0m0.120s
After:
real 0m0.032s
user 0m0.005s
sys 0m0.027s
To make sure there are no regressions on cgroup v2, I ran an artificial
reclaim/refault stress test [2] that creates (NR_CPUS * 2) cgroups,
assigns them limits, runs a worker process in each cgroup that allocates
tmpfs memory equal to quadruple the limit (to invoke reclaim
continuously), and then reads back the entire file (to invoke refaults).
All workers are run in parallel, and zram is used as a swapping backend.
Both reclaim and refault have conditional stats flushing. I ran this on a
machine with 112 cpus, once on mm-unstable, and once on mm-unstable with
this patch reverted.
(1) A few runs without this patch:
# time ./stress_reclaim_refault.sh
real 0m9.949s
user 0m0.496s
sys 14m44.974s
# time ./stress_reclaim_refault.sh
real 0m10.049s
user 0m0.486s
sys 14m55.791s
# time ./stress_reclaim_refault.sh
real 0m9.984s
user 0m0.481s
sys 14m53.841s
(2) A few runs with this patch:
# time ./stress_reclaim_refault.sh
real 0m9.885s
user 0m0.486s
sys 14m48.753s
# time ./stress_reclaim_refault.sh
real 0m9.903s
user 0m0.495s
sys 14m48.339s
# time ./stress_reclaim_refault.sh
real 0m9.861s
user 0m0.507s
sys 14m49.317s
No regressions are observed with this patch. There is actually a very
slight improvement. If I have to guess, maybe it's because we avoid
the percpu loop in count_shadow_nodes() when calling
lruvec_page_state_local(), but I could not prove this using perf, it's
probably in the noise.
[1] https://lore.kernel.org/lkml/20230725201811.GA1231514@cmpxchg.org/
[2] https://lore.kernel.org/lkml/CAJD7tkb17x=qwoO37uxyYXLEUVp15BQKR+Xfh7Sg9Hx-wTQ_=w@mail.gmail.com/
Link: https://lkml.kernel.org/r/20230803185046.1385770-1-yosryahmed@google.com
Link: https://lkml.kernel.org/r/20230726153223.821757-2-yosryahmed@google.com
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
