Linux kernel ============ The Linux kernel is the core of any Linux operating system. It manages hardware, system resources, and provides the fundamental services for all other software. Quick Start ----------- * Report a bug: See Documentation/admin-guide/reporting-issues.rst * Get the latest kernel: https://kernel.org * Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst * Join the community: https://lore.kernel.org/ Essential Documentation ----------------------- All users should be familiar with: * Building requirements: Documentation/process/changes.rst * Code of Conduct: Documentation/process/code-of-conduct.rst * License: See COPYING Documentation can be built with make htmldocs or viewed online at: https://www.kernel.org/doc/html/latest/ Who Are You? ============ Find your role below: * New Kernel Developer - Getting started with kernel development * Academic Researcher - Studying kernel internals and architecture * Security Expert - Hardening and vulnerability analysis * Backport/Maintenance Engineer - Maintaining stable kernels * System Administrator - Configuring and troubleshooting * Maintainer - Leading subsystems and reviewing patches * Hardware Vendor - Writing drivers for new hardware * Distribution Maintainer - Packaging kernels for distros * AI Coding Assistant - LLMs and AI-powered development tools For Specific Users ================== New Kernel Developer -------------------- Welcome! Start your kernel development journey here: * Getting Started: Documentation/process/development-process.rst * Your First Patch: Documentation/process/submitting-patches.rst * Coding Style: Documentation/process/coding-style.rst * Build System: Documentation/kbuild/index.rst * Development Tools: Documentation/dev-tools/index.rst * Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst * Core APIs: Documentation/core-api/index.rst Academic Researcher ------------------- Explore the kernel's architecture and internals: * Researcher Guidelines: Documentation/process/researcher-guidelines.rst * Memory Management: Documentation/mm/index.rst * Scheduler: Documentation/scheduler/index.rst * Networking Stack: Documentation/networking/index.rst * Filesystems: Documentation/filesystems/index.rst * RCU (Read-Copy Update): Documentation/RCU/index.rst * Locking Primitives: Documentation/locking/index.rst * Power Management: Documentation/power/index.rst Security Expert --------------- Security documentation and hardening guides: * Security Documentation: Documentation/security/index.rst * LSM Development: Documentation/security/lsm-development.rst * Self Protection: Documentation/security/self-protection.rst * Reporting Vulnerabilities: Documentation/process/security-bugs.rst * CVE Procedures: Documentation/process/cve.rst * Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst * Security Features: Documentation/userspace-api/seccomp_filter.rst Backport/Maintenance Engineer ----------------------------- Maintain and stabilize kernel versions: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * Backporting Guide: Documentation/process/backporting.rst * Applying Patches: Documentation/process/applying-patches.rst * Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git for Maintainers: Documentation/maintainer/configure-git.rst System Administrator -------------------- Configure, tune, and troubleshoot Linux systems: * Admin Guide: Documentation/admin-guide/index.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst * Tracing/Debugging: Documentation/trace/index.rst * Performance Security: Documentation/admin-guide/perf-security.rst * Hardware Monitoring: Documentation/hwmon/index.rst Maintainer ---------- Lead kernel subsystems and manage contributions: * Maintainer Handbook: Documentation/maintainer/index.rst * Pull Requests: Documentation/maintainer/pull-requests.rst * Managing Patches: Documentation/maintainer/modifying-patches.rst * Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst * Development Process: Documentation/process/maintainer-handbooks.rst * Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git Configuration: Documentation/maintainer/configure-git.rst Hardware Vendor --------------- Write drivers and support new hardware: * Driver API Guide: Documentation/driver-api/index.rst * Driver Model: Documentation/driver-api/driver-model/driver.rst * Device Drivers: Documentation/driver-api/infrastructure.rst * Bus Types: Documentation/driver-api/driver-model/bus.rst * Device Tree Bindings: Documentation/devicetree/bindings/ * Power Management: Documentation/driver-api/pm/index.rst * DMA API: Documentation/core-api/dma-api.rst Distribution Maintainer ----------------------- Package and distribute the kernel: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * ABI Documentation: Documentation/ABI/README * Kernel Configuration: Documentation/kbuild/kconfig.rst * Module Signing: Documentation/admin-guide/module-signing.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst AI Coding Assistant ------------------- CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and follow the AI coding assistants documentation before contributing to the Linux kernel: * Documentation/process/coding-assistants.rst This documentation contains essential requirements about licensing, attribution, and the Developer Certificate of Origin that all AI tools must comply with. Communication and Support ========================= * Mailing Lists: https://lore.kernel.org/ * IRC: #kernelnewbies on irc.oftc.net * Bugzilla: https://bugzilla.kernel.org/ * MAINTAINERS file: Lists subsystem maintainers and mailing lists * Email Clients: Documentation/process/email-clients.rst
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Pull bootconfig fixes from Masami Hiramatsu:
- fix off-by-one in xbc_verify_tree() unclosed brace error. This fixes
a wrong error place in unclosed brace error message
- check bounds before writing in __xbc_open_brace(). This fixes to
check the array index before setting array, so that the bootconfig
can support 16th-depth nested brace correctly
- fix snprintf truncation check in xbc_node_compose_key_after(). This
fixes to handle the return value of snprintf() correctly in case of
the return value == size
- Add bootconfig tests about braces Add test cases for checking error
position about unclosed brace and ensuring supporting 16th depth
nested braces correctly
* tag 'bootconfig-fixes-v7.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
bootconfig: Add bootconfig tests about braces
lib/bootconfig: fix snprintf truncation check in xbc_node_compose_key_after()
lib/bootconfig: check bounds before writing in __xbc_open_brace()
lib/bootconfig: fix off-by-one in xbc_verify_tree() unclosed brace error
Pull kvm fixes from Paolo Bonzini:
"Quite a large pull request, partly due to skipping last week and
therefore having material from ~all submaintainers in this one. About
a fourth of it is a new selftest, and a couple more changes are large
in number of files touched (fixing a -Wflex-array-member-not-at-end
compiler warning) or lines changed (reformatting of a table in the API
documentation, thanks rST).
But who am I kidding---it's a lot of commits and there are a lot of
bugs being fixed here, some of them on the nastier side like the
RISC-V ones.
ARM:
- Correctly handle deactivation of interrupts that were activated
from LRs. Since EOIcount only denotes deactivation of interrupts
that are not present in an LR, start EOIcount deactivation walk
*after* the last irq that made it into an LR
- Avoid calling into the stubs to probe for ICH_VTR_EL2.TDS when pKVM
is already enabled -- not only thhis isn't possible (pKVM will
reject the call), but it is also useless: this can only happen for
a CPU that has already booted once, and the capability will not
change
- Fix a couple of low-severity bugs in our S2 fault handling path,
affecting the recently introduced LS64 handling and the even more
esoteric handling of hwpoison in a nested context
- Address yet another syzkaller finding in the vgic initialisation,
where we would end-up destroying an uninitialised vgic with nasty
consequences
- Address an annoying case of pKVM failing to boot when some of the
memblock regions that the host is faulting in are not page-aligned
- Inject some sanity in the NV stage-2 walker by checking the limits
against the advertised PA size, and correctly report the resulting
faults
PPC:
- Fix a PPC e500 build error due to a long-standing wart that was
exposed by the recent conversion to kmalloc_obj(); rip out all the
ugliness that led to the wart
RISC-V:
- Prevent speculative out-of-bounds access using array_index_nospec()
in APLIC interrupt handling, ONE_REG regiser access, AIA CSR
access, float register access, and PMU counter access
- Fix potential use-after-free issues in kvm_riscv_gstage_get_leaf(),
kvm_riscv_aia_aplic_has_attr(), and kvm_riscv_aia_imsic_has_attr()
- Fix potential null pointer dereference in
kvm_riscv_vcpu_aia_rmw_topei()
- Fix off-by-one array access in SBI PMU
- Skip THP support check during dirty logging
- Fix error code returned for Smstateen and Ssaia ONE_REG interface
- Check host Ssaia extension when creating AIA irqchip
x86:
- Fix cases where CPUID mitigation features were incorrectly marked
as available whenever the kernel used scattered feature words for
them
- Validate _all_ GVAs, rather than just the first GVA, when
processing a range of GVAs for Hyper-V's TLB flush hypercalls
- Fix a brown paper bug in add_atomic_switch_msr()
- Use hlist_for_each_entry_srcu() when traversing mask_notifier_list,
to fix a lockdep warning; KVM doesn't hold RCU, just irq_srcu
- Ensure AVIC VMCB fields are initialized if the VM has an in-kernel
local APIC (and AVIC is enabled at the module level)
- Update CR8 write interception when AVIC is (de)activated, to fix a
bug where the guest can run in perpetuity with the CR8 intercept
enabled
- Add a quirk to skip the consistency check on FREEZE_IN_SMM, i.e. to
allow L1 hypervisors to set FREEZE_IN_SMM. This reverts (by
default) an unintentional tightening of userspace ABI in 6.17, and
provides some amount of backwards compatibility with hypervisors
who want to freeze PMCs on VM-Entry
- Validate the VMCS/VMCB on return to a nested guest from SMM,
because either userspace or the guest could stash invalid values in
memory and trigger the processor's consistency checks
Generic:
- Remove a subtle pseudo-overlay of kvm_stats_desc, which, aside from
being unnecessary and confusing, triggered compiler warnings due to
-Wflex-array-member-not-at-end
- Document that vcpu->mutex is take outside of kvm->slots_lock and
kvm->slots_arch_lock, which is intentional and desirable despite
being rather unintuitive
Selftests:
- Increase the maximum number of NUMA nodes in the guest_memfd
selftest to 64 (from 8)"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (43 commits)
KVM: selftests: Verify SEV+ guests can read and write EFER, CR0, CR4, and CR8
Documentation: kvm: fix formatting of the quirks table
KVM: x86: clarify leave_smm() return value
selftests: kvm: add a test that VMX validates controls on RSM
selftests: kvm: extract common functionality out of smm_test.c
KVM: SVM: check validity of VMCB controls when returning from SMM
KVM: VMX: check validity of VMCS controls when returning from SMM
KVM: SVM: Set/clear CR8 write interception when AVIC is (de)activated
KVM: SVM: Initialize AVIC VMCB fields if AVIC is enabled with in-kernel APIC
KVM: x86: Introduce KVM_X86_QUIRK_VMCS12_ALLOW_FREEZE_IN_SMM
KVM: x86: Fix SRCU list traversal in kvm_fire_mask_notifiers()
KVM: VMX: Fix a wrong MSR update in add_atomic_switch_msr()
KVM: x86: hyper-v: Validate all GVAs during PV TLB flush
KVM: x86: synthesize CPUID bits only if CPU capability is set
KVM: PPC: e500: Rip out "struct tlbe_ref"
KVM: PPC: e500: Fix build error due to using kmalloc_obj() with wrong type
KVM: selftests: Increase 'maxnode' for guest_memfd tests
KVM: arm64: pkvm: Don't reprobe for ICH_VTR_EL2.TDS on CPU hotplug
KVM: arm64: vgic: Pick EOIcount deactivations from AP-list tail
KVM: arm64: Remove the redundant ISB in __kvm_at_s1e2()
...
Add more bootconfig tests for checking the error message of
non closing brace and max number of nested braces.
Link: https://lore.kernel.org/all/177337553551.416919.11217619471547711262.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull powerpc fixes from Madhavan Srinivasan:
- Fix KUAP warning in VMX usercopy path
- Fix lockdep warning during PCI enumeration
- Fix to move CMA reservations to arch_mm_preinit
- Fix to check current->mm is alive before getting user callchain
Thanks to Aboorva Devarajan, Christophe Leroy (CS GROUP), Dan Horák,
Nicolin Chen, Nilay Shroff, Qiao Zhao, Ritesh Harjani (IBM), Saket Kumar
Bhaskar, Sayali Patil, Shrikanth Hegde, Venkat Rao Bagalkote, and Viktor
Malik.
* tag 'powerpc-7.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/iommu: fix lockdep warning during PCI enumeration
powerpc/selftests/copyloops: extend selftest to exercise __copy_tofrom_user_power7_vmx
powerpc: fix KUAP warning in VMX usercopy path
powerpc, perf: Check that current->mm is alive before getting user callchain
powerpc/mem: Move CMA reservations to arch_mm_preinit
Add "do no harm" testing of EFER, CR0, CR4, and CR8 for SEV+ guests to
verify that the guest can read and write the registers, without hitting
e.g. a #VC on SEV-ES guests due to KVM incorrectly trying to intercept a
register.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260310211841.2552361-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
snprintf() returns the number of characters that would have been
written excluding the NUL terminator. Output is truncated when the
return value is >= the buffer size, not just > the buffer size.
When ret == size, the current code takes the non-truncated path,
advancing buf by ret and reducing size to 0. This is wrong because
the output was actually truncated (the last character was replaced by
NUL). Fix by using >= so the truncation path is taken correctly.
Link: https://lore.kernel.org/all/20260312191143.28719-4-objecting@objecting.org/
Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support")
Cc: stable@vger.kernel.org
Signed-off-by: Josh Law <objecting@objecting.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull x86 fix from Ingo Molnar:
"Work around S2RAM hang if the firmware unexpectedly re-enables the
x2apic hardware while it was disabled by the kernel.
Force-disable it again and issue a warning into the syslog"
* tag 'x86-urgent-2026-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Disable x2apic on resume if the kernel expects so
Commit a75b2be249d6 ("iommu: Add iommu_driver_get_domain_for_dev()
helper") introduced iommu_driver_get_domain_for_dev() for driver
code paths that hold iommu_group->mutex while attaching a device
to an IOMMU domain.
The same commit also added a lockdep assertion in
iommu_get_domain_for_dev() to ensure that callers do not hold
iommu_group->mutex when invoking it.
On powerpc platforms, when PCI device ownership is switched from
BLOCKED to the PLATFORM domain, the attach callback
spapr_tce_platform_iommu_attach_dev() still calls
iommu_get_domain_for_dev(). This happens while iommu_group->mutex
is held during domain switching, which triggers the lockdep warning
below during PCI enumeration:
WARNING: drivers/iommu/iommu.c:2252 at iommu_get_domain_for_dev+0x38/0x80, CPU#2: swapper/0/1
Modules linked in:
CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Not tainted 7.0.0-rc2+ #35 PREEMPT
Hardware name: IBM,9105-22A Power11 (architected) 0x820200 0xf000007 of:IBM,FW1120.00 (RB1120_115) hv:phyp pSeries
NIP: c000000000c244c4 LR: c00000000005b5a4 CTR: c00000000005b578
REGS: c00000000a7bf280 TRAP: 0700 Not tainted (7.0.0-rc2+)
MSR: 8000000002029033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 22004422 XER: 0000000a
CFAR: c000000000c24508 IRQMASK: 0
GPR00: c00000000005b5a4 c00000000a7bf520 c000000001dc8100 0000000000000001
GPR04: c00000000f972f10 0000000000000000 0000000000000000 0000000000000001
GPR08: 0000001ffbc60000 0000000000000001 0000000000000000 0000000000000000
GPR12: c00000000005b578 c000001fffffe480 c000000000011618 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: ffffffffffffefff 0000000000000000 c000000002d30eb0 0000000000000001
GPR24: c0000000017881f8 0000000000000000 0000000000000001 c00000000f972e00
GPR28: c00000000bbba0d0 0000000000000000 c00000000bbba0d0 c00000000f972e00
NIP [c000000000c244c4] iommu_get_domain_for_dev+0x38/0x80
LR [c00000000005b5a4] spapr_tce_platform_iommu_attach_dev+0x2c/0x98
Call Trace:
iommu_get_domain_for_dev+0x68/0x80 (unreliable)
spapr_tce_platform_iommu_attach_dev+0x2c/0x98
__iommu_attach_device+0x44/0x220
__iommu_device_set_domain+0xf4/0x194
__iommu_group_set_domain_internal+0xec/0x228
iommu_setup_default_domain+0x5f4/0x6a4
__iommu_probe_device+0x674/0x724
iommu_probe_device+0x50/0xb4
iommu_add_device+0x48/0x198
pci_dma_dev_setup_pSeriesLP+0x198/0x4f0
pcibios_bus_add_device+0x80/0x464
pci_bus_add_device+0x40/0x100
pci_bus_add_devices+0x54/0xb0
pcibios_init+0xd8/0x140
do_one_initcall+0x8c/0x598
kernel_init_freeable+0x3ec/0x850
kernel_init+0x34/0x270
ret_from_kernel_user_thread+0x14/0x1c
Fix this by using iommu_driver_get_domain_for_dev() instead of
iommu_get_domain_for_dev() in spapr_tce_platform_iommu_attach_dev(),
which is the appropriate helper for callers holding the group mutex.
Cc: stable@vger.kernel.org
Fixes: a75b2be249d6 ("iommu: Add iommu_driver_get_domain_for_dev() helper")
Closes: https://patchwork.ozlabs.org/project/linuxppc-dev/patch/d5c834ff-4c95-44dd-8bef-57242d63aeee@linux.ibm.com/
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
[Maddy: Added Closes, tested and reviewed by tags]
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260310082129.3630996-1-nilay@linux.ibm.com
A recently added quirk does not fit in the left column of the table,
so it all has to be reformatted and realigned.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The bounds check for brace_index happens after the array write.
While the current call pattern prevents an actual out-of-bounds
access (the previous call would have returned an error), the
write-before-check pattern is fragile and would become a real
out-of-bounds write if the error return were ever not propagated.
Move the bounds check before the array write so the function is
self-contained and safe regardless of caller behavior.
Link: https://lore.kernel.org/all/20260312191143.28719-3-objecting@objecting.org/
Fixes: ead1e19ad905 ("lib/bootconfig: Fix a bug of breaking existing tree nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Josh Law <objecting@objecting.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull timer fix from Ingo Molnar:
"Fix function tracer recursion bug by marking jiffies_64_to_clock_t()
notrace"
* tag 'timers-urgent-2026-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time/jiffies: Mark jiffies_64_to_clock_t() notrace
When resuming from s2ram, firmware may re-enable x2apic mode, which may have
been disabled by the kernel during boot either because it doesn't support IRQ
remapping or for other reasons. This causes the kernel to continue using the
xapic interface, while the hardware is in x2apic mode, which causes hangs.
This happens on defconfig + bare metal + s2ram.
Fix this in lapic_resume() by disabling x2apic if the kernel expects it to be
disabled, i.e. when x2apic_mode = 0.
The ACPI v6.6 spec, Section 16.3 [1] says firmware restores either the
pre-sleep configuration or initial boot configuration for each CPU, including
MSR state:
When executing from the power-on reset vector as a result of waking from an
S2 or S3 sleep state, the platform firmware performs only the hardware
initialization required to restore the system to either the state the
platform was in prior to the initial operating system boot, or to the
pre-sleep configuration state. In multiprocessor systems, non-boot
processors should be placed in the same state as prior to the initial
operating system boot.
(further ahead)
If this is an S2 or S3 wake, then the platform runtime firmware restores
minimum context of the system before jumping to the waking vector. This
includes:
CPU configuration. Platform runtime firmware restores the pre-sleep
configuration or initial boot configuration of each CPU (MSR, MTRR,
firmware update, SMBase, and so on). Interrupts must be disabled (for
IA-32 processors, disabled by CLI instruction).
(and other things)
So at least as per the spec, re-enablement of x2apic by the firmware is
allowed if "x2apic on" is a part of the initial boot configuration.
[1] https://uefi.org/specs/ACPI/6.6/16_Waking_and_Sleeping.html#initialization
[ bp: Massage. ]
Fixes: 6e1cb38a2aef ("x64, x2apic/intr-remap: add x2apic support, including enabling interrupt-remapping")
Co-developed-by: Rahul Bukte <rahul.bukte@sony.com>
Signed-off-by: Rahul Bukte <rahul.bukte@sony.com>
Signed-off-by: Shashank Balaji <shashank.mahadasyam@sony.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260306-x2apic-fix-v2-1-bee99c12efa3@sony.com
The new PowerPC VMX fast path (__copy_tofrom_user_power7_vmx) is not
exercised by existing copyloops selftests. This patch updates
the selftest to exercise the VMX variant, ensuring the VMX copy path
is validated.
Changes include:
- COPY_LOOP=test___copy_tofrom_user_power7_vmx with -D VMX_TEST is used
in existing selftest build targets.
- Inclusion of ../utils.c to provide get_auxv_entry() for hardware
feature detection.
- At runtime, the test skips execution if Altivec is not available.
- Copy sizes above VMX_COPY_THRESHOLD are used to ensure the VMX
path is taken.
This enables validation of the VMX fast path without affecting systems
that do not support Altivec.
Signed-off-by: Sayali Patil <sayalip@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260304122201.153049-2-sayalip@linux.ibm.com
The return value of vmx_leave_smm() is unrelated from that of
nested_vmx_enter_non_root_mode(). Check explicitly for success
(which happens to be 0) and return 1 just like everywhere
else in vmx_leave_smm().
Likewise, in svm_leave_smm() return 0/1 instead of the 0/1/-errno
returned by tenter_svm_guest_mode().
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
__xbc_open_brace() pushes entries with post-increment
(open_brace[brace_index++]), so brace_index always points one past
the last valid entry. xbc_verify_tree() reads open_brace[brace_index]
to report which brace is unclosed, but this is one past the last
pushed entry and contains stale/zero data, causing the error message
to reference the wrong node.
Use open_brace[brace_index - 1] to correctly identify the unclosed
brace. brace_index is known to be > 0 here since we are inside the
if (brace_index) guard.
Link: https://lore.kernel.org/all/20260312191143.28719-2-objecting@objecting.org/
Fixes: ead1e19ad905 ("lib/bootconfig: Fix a bug of breaking existing tree nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull scheduler fixes from Ingo Molnar:
"More MM-CID fixes, mostly fixing hangs/races:
- Fix CID hangs due to a race between concurrent forks
- Fix vfork()/CLONE_VM MMCID bug causing hangs
- Remove pointless preemption guard
- Fix CID task list walk performance regression on large systems
by removing the known-flaky and slow counting logic using
for_each_process_thread() in mm_cid_*fixup_tasks_to_cpus(), and
implementing a simple sched_mm_cid::node list instead"
* tag 'sched-urgent-2026-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/mmcid: Avoid full tasklist walks
sched/mmcid: Remove pointless preempt guard
sched/mmcid: Handle vfork()/CLONE_VM correctly
sched/mmcid: Prevent CID stalls due to concurrent forks
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