In order to comply with PEP 8, the first parameter of a class should be
__init__.
Signed-off-by: Elijah Conners <business@elijahpepe.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

It could directly return 'cgroup_update_dfl_csses' to simplify code.
Signed-off-by: William Dean <williamsukatube@163.com>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

After merging 836ac87d ("cgroup: fix cgroup_get_from_id") into for-6.1, its
combination with two commits in for-6.1 - 4534dee9 ("cgroup: cgroup: Honor
caller's cgroup NS when resolving cgroup id") and fa7e439c ("cgroup:
Homogenize cgroup_get_from_id() return value") - makes the gotos in the
error handling path too ugly while not adding anything of value.

All that the gotos are saving is one extra kernfs_put() call. Let's remove
the gotos and perform error returns directly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Michal Koutný <mkoutny@suse.com>

for-6.0 has the following fix for cgroup_get_from_id().

  836ac87d ("cgroup: fix cgroup_get_from_id")

which conflicts with the following two commits in for-6.1.

  4534dee9 ("cgroup: cgroup: Honor caller's cgroup NS when resolving cgroup id")
  fa7e439c ("cgroup: Homogenize cgroup_get_from_id() return value")

While the resolution is straightforward, the code ends up pretty ugly
afterwards. Let's pull for-6.0-fixes into for-6.1 so that the code can be
fixed up there.
Signed-off-by: Tejun Heo <tj@kernel.org>

cgroup has to be one kernfs dir, otherwise kernel panic is caused,
especially cgroup id is provide from userspace.
Reported-by: Marco Patalano <mpatalan@redhat.com>
Fixes: 6b658c48 ("scsi: cgroup: Add cgroup_get_from_id()")
Cc: Muneendra <muneendra.kumar@broadcom.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Mukesh Ojha <quic_mojha@quicinc.com>
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Tejun Heo <tj@kernel.org>

The function sched_partition_show cannot execute seq_puts, delete the
invalid code.

kernel/cgroup/cpuset.c:2849 sched_partition_show() warn: ignoring unreachable code.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2087Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

CFTYPE_PRESSURE is used to flag PSI related files so that they are not
created if PSI is disabled during boot. It's a bit weird to use a generic
flag to mark a specific file type. Let's instead move the PSI files into its
own cftypes array and add/rm them conditionally. This is a bit more code but
cleaner.

No userland visible changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>

Let's track whether a cftype is currently added or not using a new flag
__CFTYPE_ADDED so that duplicate operations can be failed safely and
consistently allow using empty cftypes.
Signed-off-by: Tejun Heo <tj@kernel.org>

Waiman has been very active with cpuset recently and I've been cc'ing him
for cpuset related changes for a while now. Let's make him a cpuset
maintainer.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Waiman Long <longman@redhat.com>

Add a test script test_cpuset_prs.sh with a helper program wait_inotify
for exercising the cpuset v2 partition root state code.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Update Documentation/admin-guide/cgroup-v2.rst on the newly introduced
"isolated" cpuset partition type as well as other changes made in other
cpuset patches.
Signed-off-by: Waiman Long <longman@redhat.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Currently, changes in "cpust.cpus" of a partition root is not allowed if
it violates the sibling cpu exclusivity rule when the check is done
in the validate_change() function. That is inconsistent with the
other cpuset changes that are always allowed but may make a partition
invalid.

Update the cpuset code to allow cpumask change even if it violates the
sibling cpu exclusivity rule, but invalidate the partition instead
just like the other changes. However, other sibling partitions with
conflicting cpumask will also be invalidated in order to not violating
the exclusivity rule. This behavior is specific to this partition
rule violation.

Note that a previous commit has made sibling cpu exclusivity rule check
the last check of validate_change(). So if -EINVAL is returned, we can
be sure that sibling cpu exclusivity rule violation is the only rule
that is broken.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

This patch moves down the exclusive cpu and memory check in
validate_change(). There is no functional change.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

There are a number of different reasons which can cause a partition to
become invalid. A user seeing an invalid partition may not know exactly
why. To help user to get a better understanding of the underlying reason,
The cpuset.cpus.partition control file, when read, will now report the
reason why a partition become invalid. When a partition does become
invalid, reading the control file will show "root invalid (<reason>)"
where <reason> is a string that describes why the partition is invalid.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Cpuset v1 uses the sched_load_balance control file to determine if load
balancing should be enabled.  Cpuset v2 gets rid of sched_load_balance
as its use may require disabling load balancing at cgroup root.

For workloads that require very low latency like DPDK, the latency
jitters caused by periodic load balancing may exceed the desired
latency limit.

When cpuset v2 is in use, the only way to avoid this latency cost is to
use the "isolcpus=" kernel boot option to isolate a set of CPUs. After
the kernel boot, however, there is no way to add or remove CPUs from
this isolated set. For workloads that are more dynamic in nature, that
means users have to provision enough CPUs for the worst case situation
resulting in excess idle CPUs.

To address this issue for cpuset v2, a new cpuset.cpus.partition type
"isolated" is added which allows the creation of a cpuset partition
without load balancing. This will allow system administrators to
dynamically adjust the size of isolated partition to the current need
of the workload without rebooting the system.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Currently, enabling a partition root is only allowed if all the
constraints of a valid partition are satisfied. Even changes to
"cpuset.cpus" may not be allowed in some cases. Moreover, there are
limits to changes made to a parent cpuset if it is a valid partition
root. This is contrary to the general cgroup v2 philosophy.

This patch relaxes the constraints of changing the state of "cpuset.cpus"
and "cpuset.cpus.partition". Now all valid changes ("member" or "root")
to "cpuset.cpus.partition" are allowed even if there are child cpusets
underneath it.

Trying to make a cpuset a partition root, however, will cause its state
to become invalid if the following constraints of a valid partition
root are not satisfied.

 1) The "cpuset.cpus" is non-empty and exclusive.
 2) The parent cpuset is a valid partition root.
 3) The "cpuset.cpus" overlaps parent's "cpuset.cpus".

Similarly, almost all changes to "cpuset.cpus" are allowed with the
exception that if the underlying CS_CPU_EXCLUSIVE flag is set, the
exclusivity rule will still apply.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Currently, a partition root cannot have empty "cpuset.cpus.effective".
As a result, a parent partition root cannot distribute out all its
CPUs to child partitions with no CPUs left. However in most cases,
there shouldn't be any tasks associated with intermediate nodes of the
default hierarchy. So the current rule is too restrictive and can waste
valuable CPU resource.

To address this issue, we are now allowing a partition to have empty
"cpuset.cpus.effective" as long as it has no task. Since cpuset is
threaded, no-internal-process rule does not apply. So it is possible
to have tasks in a partition root with child sub-partitions even though
that should be uncommon.

A parent partition with no task can now have all its CPUs distributed out
to its child partitions. The top cpuset always have some house-keeping
tasks running and so its list of effective cpu can't be empty.

Once a partition with empty "cpuset.cpus.effective" is formed, no
new task can be moved into it until "cpuset.cpus.effective" becomes
non-empty.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

The partition root state (PRS) macro names do not currently match the
external names. Change them to match the external names and add helper
functions to read or change the state.

Shorten the cpuset argument of update_parent_subparts_cpumask() to cs
to match other cpuset functions.

Remove the new_prs argument from notify_partition_change() as the
cs->partition_root_state has already been set to new_prs before it
is called.

There is no functional change.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Previously, update_tasks_cpumask() is not supposed to be called with
top cpuset. With cpuset partition that takes CPUs away from the top
cpuset, adjusting the cpus_mask of the tasks in the top cpuset is
necessary. Percpu kthreads, however, are ignored.

Fixes: ee8dde0c ("cpuset: Add new v2 cpuset.sched.partition flag")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

pids.peak tracks the high watermark of usage for number of pids. This
helps give a better baseline on which to set pids.max. Polling
pids.current isn't really feasible, since it would potentially miss
short-lived spikes.

This interface is analogous to memory.peak.
Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

There's a seemingly harmless data-race around cgrp_dfl_visible detected by
kernel concurrency sanitizer. Let's remove it by throwing WRITE/READ_ONCE at
it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Abhishek Shah <abhishek.shah@columbia.edu>
Cc: Gabriel Ryan <gabe@cs.columbia.edu>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Link: https://lore.kernel.org/netdev/20220819072256.fn7ctciefy4fc4cu@wittgenstein/

Pull powerpc fixes from Michael Ellerman:

 - Fix handling of PCI domains in /proc on 32-bit systems using the
   recently added support for numbering buses from zero for each domain.

 - A fix and a revert for some changes to use READ/WRITE_ONCE() which
   caused problems with KASAN enabled due to sanitisation calls being
   introduced in low-level paths that can't cope with it.

 - Fix build errors on 32-bit caused by the syscall table being
   misaligned sometimes.

 - Two fixes to get IBM Cell native machines booting again, which had
   bit-rotted while my QS22 was temporarily out of action.

 - Fix the papr_scm driver to not assume the order of events returned by
   the hypervisor is stable, and a related compile fix.

Thanks to Aneesh Kumar K.V, Christophe Leroy, Jordan Niethe, Kajol Jain,
Masahiro Yamada, Nathan Chancellor, Pali Rohár, Vaibhav Jain, and Zhouyi
Zhou.

* tag 'powerpc-6.0-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Ensure rc is always initialized in papr_scm_pmu_register()
  Revert "powerpc/irq: Don't open code irq_soft_mask helpers"
  powerpc: Fix hard_irq_disable() with sanitizer
  powerpc/rtas: Fix RTAS MSR[HV] handling for Cell
  Revert "powerpc: Remove unused FW_FEATURE_NATIVE references"
  powerpc: align syscall table for ppc32
  powerpc/pci: Enable PCI domains in /proc when PCI bus numbers are not unique
  powerpc/papr_scm: Fix nvdimm event mappings

Pull kvm fixes from Paolo Bonzini:
 "s390:

   - PCI interpretation compile fixes

  RISC-V:

   - fix unused variable warnings in vcpu_timer.c

   - move extern sbi_ext declarations to a header

  x86:

   - check validity of argument to KVM_SET_MP_STATE

   - use guest's global_ctrl to completely disable guest PEBS

   - fix a memory leak on memory allocation failure

   - mask off unsupported and unknown bits of IA32_ARCH_CAPABILITIES

   - fix build failure with Clang integrated assembler

   - fix MSR interception

   - always flush TLBs when enabling dirty logging"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: check validity of argument to KVM_SET_MP_STATE
  perf/x86/core: Completely disable guest PEBS via guest's global_ctrl
  KVM: x86: fix memoryleak in kvm_arch_vcpu_create()
  KVM: x86: Mask off unsupported and unknown bits of IA32_ARCH_CAPABILITIES
  KVM: s390: pci: Hook to access KVM lowlevel from VFIO
  riscv: kvm: move extern sbi_ext declarations to a header
  riscv: kvm: vcpu_timer: fix unused variable warnings
  KVM: selftests: Fix ambiguous mov in KVM_ASM_SAFE()
  KVM: selftests: Fix KVM_EXCEPTION_MAGIC build with Clang
  KVM: VMX: Heed the 'msr' argument in msr_write_intercepted()
  kvm: x86: mmu: Always flush TLBs when enabling dirty logging
  kvm: x86: mmu: Drop the need_remote_flush() function

-Wformat was recently re-enabled for builds with clang, then quickly
re-disabled, due to concerns stemming from the frequency of default
argument promotion related warning instances.

commit 258fafcd ("Makefile.extrawarn: re-enable -Wformat for clang")
commit 21f9c8a1 ("Revert "Makefile.extrawarn: re-enable -Wformat for clang"")

ISO WG14 has ratified N2562 to address default argument promotion
explicitly for printf, as part of the upcoming ISO C2X standard.

The behavior of clang was changed in clang-16 to not warn for the cited
cases in all language modes.

Add a version check, so that users of clang-16 now get the full effect
of -Wformat. For older clang versions, re-enable flags under the
-Wformat group that way users still get some useful checks related to
format strings, without noisy default argument promotion warnings. I
intentionally omitted -Wformat-y2k and -Wformat-security from being
re-enabled, which are also part of -Wformat in clang-16.

Link: https://github.com/ClangBuiltLinux/linux/issues/378
Link: https://github.com/llvm/llvm-project/issues/57102
Link: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2562.pdfSuggested-by: Justin Stitt <jstitt007@gmail.com>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Youngmin Nam <youngmin.nam@samsung.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull gpio fixes from Bartosz Golaszewski:
 "A a set of fixes from the GPIO subsystem.

  Most are small driver fixes except the realtek-otto driver patch which
  is pretty big but addresses a significant flaw that can cause the CPU
  to stay infinitely busy on uncleared ISR on some platforms.

  Summary:
   - MAINTAINERS update
   - fix resource leaks in gpio-mockup and gpio-pxa
   - add missing locking in gpio-pca953x
   - use 32-bit I/O in gpio-realtek-otto
   - make irq_chip structures immutable in four more drivers"

* tag 'gpio-fixes-for-v6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpio: ws16c48: Make irq_chip immutable
  gpio: 104-idio-16: Make irq_chip immutable
  gpio: 104-idi-48: Make irq_chip immutable
  gpio: 104-dio-48e: Make irq_chip immutable
  gpio: realtek-otto: switch to 32-bit I/O
  gpio: pca953x: Add mutex_lock for regcache sync in PM
  gpio: mockup: remove gpio debugfs when remove device
  gpio: pxa: use devres for the clock struct
  MAINTAINERS: rectify entry for XILINX GPIO DRIVER

Kernel warns about mutable irq_chips:

    "not an immutable chip, please consider fixing!"

Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the
new helper functions, and call the appropriate gpiolib functions.
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

Kernel warns about mutable irq_chips:

    "not an immutable chip, please consider fixing!"

Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the
new helper functions, and call the appropriate gpiolib functions.
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

Kernel warns about mutable irq_chips:

    "not an immutable chip, please consider fixing!"

Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the
new helper functions, and call the appropriate gpiolib functions.
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

Kernel warns about mutable irq_chips:

    "not an immutable chip, please consider fixing!"

Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the
new helper functions, and call the appropriate gpiolib functions.
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

Pull xen fixes from Juergen Gross:

 - a minor fix for the Xen grant driver

 - a small series fixing a recently introduced problem in the Xen
   blkfront/blkback drivers with negotiation of feature usage

* tag 'for-linus-6.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/grants: prevent integer overflow in gnttab_dma_alloc_pages()
  xen-blkfront: Cache feature_persistent value before advertisement
  xen-blkfront: Advertise feature-persistent as user requested
  xen-blkback: Advertise feature-persistent as user requested

Merge tag 'loongarch-fixes-6.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch fixes from Huacai Chen:
 "Fix several build errors or warnings, cleanup some code, and adjust
  arch_do_signal_or_restart() to adapt generic entry"

* tag 'loongarch-fixes-6.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: mm: Remove the unneeded result variable
  LoongArch: Fix arch_remove_memory() undefined build error
  LoongArch: Fix section mismatch due to acpi_os_ioremap()
  LoongArch: Improve dump_tlb() output messages
  LoongArch: Adjust arch_do_signal_or_restart() to adapt generic entry
  LoongArch: Avoid orphan input sections

Pull s390 fixes from Vasily Gorbik:

 - Update defconfigs

 - Fix linker script to align nospec tables correctly to avoid
   potentially unbootable kernel with some config options

 - Fix alignment check in prepare_hugepage_range() for 2GB hugepages to
   avoid BUG in __unmap_hugepage_range() for unaligned mappings later

 - Remove useless hugepage address alignment in hugetlb fault handling

* tag 's390-6.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/hugetlb: fix prepare_hugepage_range() check for 2 GB hugepages
  s390: update defconfigs
  s390: fix nospec table alignments
  s390/mm: remove useless hugepage address alignment

Pull input fixes from Dmitry Torokhov:

 - GT1158 ID added to Goodix touchscreen driver

 - Boeder Force Feedback Wheel USB added to iforce joystick driver

 - fixup for iforce driver to avoid hangups

 - fix autoloading of rk805-pwrkey driver.

* tag 'input-for-v6.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: iforce - add support for Boeder Force Feedback Wheel
  Input: iforce - wake up after clearing IFORCE_XMIT_RUNNING flag
  Input: goodix - add compatible string for GT1158
  MAINTAINERS: add include/dt-bindings/input to INPUT DRIVERS
  Input: rk805-pwrkey - fix module autoloading
  Input: goodix - add support for GT1158
  dt-bindings: input: touchscreen: add compatible string for Goodix GT1158

Pull tty/serial driver fixes from Greg KH:
 "Here are some small tty/serial/vt driver fixes for 6.0-rc4 that
  resolve a number of reported issues:

   - n_gsm fixups for previous changes that caused problems

   - much-reported serdev crash fix that showed up in 6.0-rc1

   - vt font selection bugfix

   - kerneldoc build warning fixes

   - other tiny serial core fixes

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'tty-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: n_gsm: avoid call of sleeping functions from atomic context
  tty: n_gsm: replace kicktimer with delayed_work
  tty: n_gsm: initialize more members at gsm_alloc_mux()
  tty: n_gsm: add sanity check for gsm->receive in gsm_receive_buf()
  tty: serial: atmel: Preserve previous USART mode if RS485 disabled
  tty: serial: lpuart: disable flow control while waiting for the transmit engine to complete
  tty: Fix lookahead_buf crash with serdev
  serial: fsl_lpuart: RS485 RTS polariy is inverse
  vt: Clear selection before changing the font
  serial: document start_rx member at struct uart_ops

Pull staging driver fixes from Greg KH:
 "Here are three small staging driver fixes for 6.0-rc4 that resolve
  some reported problems and add some a device id:

   - new device id for r8188eu driver

   - use-after-free bugfixes for the rtl8712 driver

   - fix up firmware dependency problem for the r8188eu driver

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'staging-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: rtl8712: fix use after free bugs
  staging: r8188eu: Add Rosewill USB-N150 Nano to device tables
  staging: r8188eu: add firmware dependency

Pull clk fixes from Stephen Boyd:
 "Here's a collection of primarily clk driver fixes, with a couple fixes
  to the core framework.

  We had to revert out a commit that affected boot on some devices that
  have the CLK_OPS_PARENT_ENABLE flag set. It isn't critical to have
  that fix so we'll try again next time.

  Driver side fixes include:

   - Plug an OF-node refcount bug in the TI clk driver

   - Fix the error handling in the raspberry pi firmware get_rate so
     that errors don't look like valid frequencies

   - Avoid going out of bounds in the raspberry pi driver too if the
     video firmware returns something we're not expecting"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  Revert "clk: core: Honor CLK_OPS_PARENT_ENABLE for clk gate ops"
  clk: bcm: rpi: Show clock id limit in error case
  clk: bcm: rpi: Add missing newline
  clk: bcm: rpi: Prevent out-of-bounds access
  clk: bcm: rpi: Fix error handling of raspberrypi_fw_get_rate
  clk: core: Fix runtime PM sequence in clk_core_unprepare()
  clk: core: Honor CLK_OPS_PARENT_ENABLE for clk gate ops
  clk: ti: Fix missing of_node_get() ti_find_clock_provider()

Merge tag 'hwmon-for-v6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Fix out of bounds access in gpio-fan driver

 - Fix VOUT margin caching in PMBus core

 - Avoid error message after -EPROBE_DEFER from devm_regulator_register()

* tag 'hwmon-for-v6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (gpio-fan) Fix array out of bounds access
  hwmon: (pmbus) Fix vout margin caching
  hwmon: (pmbus) Use dev_err_probe() to filter -EPROBE_DEFER error messages

The mmap lock protects the page walker from changes to the page tables
during the walk.  However a read lock is insufficient to protect those
areas which don't have a VMA as munmap() detaches the VMAs before
downgrading to a read lock and actually tearing down PTEs/page tables.

For users of walk_page_range() the solution is to simply call pte_hole()
immediately without checking the actual page tables when a VMA is not
present. We now never call __walk_page_range() without a valid vma.

For walk_page_range_novma() the locking requirements are tightened to
require the mmap write lock to be taken, and then walking the pgd
directly with 'no_vma' set.

This in turn means that all page walkers either have a valid vma, or
it's that special 'novma' case for page table debugging.  As a result,
all the odd '(!walk->vma && !walk->no_vma)' tests can be removed.

Fixes: dd2283f2 ("mm: mmap: zap pages with read mmap_sem in munmap")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Return the value pa_to_nid() directly instead of storing it in another
redundant variable.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

The kernel build error when unslected CONFIG_MEMORY_HOTREMOVE because
arch_remove_memory() is needed by mm/memory_hotplug.c but undefined.

Some build error messages like:

 LD      vmlinux.o
 MODPOST vmlinux.symvers
 MODINFO modules.builtin.modinfo
 GEN     modules.builtin
 LD      .tmp_vmlinux.kallsyms1
loongarch64-linux-gnu-ld: mm/memory_hotplug.o: in function `.L242':
memory_hotplug.c:(.ref.text+0x930): undefined reference to `arch_remove_memory'
make: *** [Makefile:1169：vmlinux] 错误 1

Removed CONFIG_MEMORY_HOTREMOVE requirement and rearrange the file refer
to the definitions of other platform architectures.
Signed-off-by: Yupeng Li <liyupeng@zbhlos.com>
Signed-off-by: Caicai <caizp2008@163.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>