kernel/git/next/linux-next.git/scripts/gdb, branch master

mm/sparse: relax struct mem_section size constraints

2026-09-06T03:21:40+00:00

Patch series "mm: Introduce section-based vmemmap optimization for HugeTLB", v5. HugeTLB vmemmap optimization currently has its own early boot setup path. It pre-populates optimized vmemmap mappings before the normal sparse-vmemmap population code runs, and sparsemem carries SPARSEMEM_VMEMMAP_PREINIT only to support that special case. That makes the HugeTLB vmemmap optimization path harder to share with other users of sparse-vmemmap optimization and leaves a fair amount of HugeTLB-specific boot-time state in the generic memory initialization flow. This series introduces section-based vmemmap optimization support in the sparse-vmemmap code and switches HugeTLB bootmem pages over to it. Instead of having HugeTLB pre-populate optimized vmemmap mappings itself, HugeTLB now records the compound page order in the corresponding memory sections. The generic sparse-vmemmap population path can then allocate or reuse shared tail vmemmap pages based on section metadata. The patches are organized as follows: - patches 1-2 prepare sparsemem and vmemmap optimization metadata - patches 3-8 teach the common sparse-vmemmap paths to use that state - patches 9-10 switch HugeTLB bootmem optimization to the section-based path - patches 11-17 clean up sparsemem and HugeTLB bootmem code that is no longer needed after the conversion This is intended to be the second smaller step toward the broader HVO generalization [1]. The device DAX conversion and the wider HVO consolidation are left for follow-up series. This patch (of 17): struct mem_section is currently forced to a power-of-2 size so the section-to-root lookup can use a mask instead of a modulo. That requirement makes future extensions harder than necessary: adding a small field can require configuration-dependent padding or layout checks just to preserve the lookup scheme. Keep the lookup correct for any struct mem_section size by using a plain modulo instead. Do not leave the layout entirely unconstrained, though. Keep struct mem_section double-word aligned so modest size changes, such as adding another word-sized field on 64-bit systems, still keep a compact and efficient layout. If future fields grow the structure beyond that sweet spot, the lookup remains correct; only the exact layout efficiency changes. Link: https://lore.kernel.org/20260825084608.47437-1-songmuchun@bytedance.com Link: https://lore.kernel.org/20260825084608.47437-2-songmuchun@bytedance.com Link: https://lore.kernel.org/linux-mm/20260513130542.35604-1-songmuchun@bytedance.com/ [1] Signed-off-by: Muchun Song Acked-by: Mike Rapoport (Microsoft) Cc: David Hildenbrand Cc: David Laight Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Oscar Salvador Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Qi Zheng Signed-off-by: Andrew Morton

mm: drop stale MAX_ORDER references

2026-09-06T03:21:34+00:00

The treewide rename in commit 5e0a760b4441 ("mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER") left a few spots still using the old name: - two comments in include/net/mana/mana.h and mm/page_alloc.c; - the gdb helper scripts/gdb/linux/mm.py, where self.MAX_ORDER is a local mirror of the kernel's MAX_ORDER define. Rename the leftover instances to MAX_PAGE_ORDER so the tree is consistent. No functional changes. Link: https://lore.kernel.org/20260819082052.3338603-1-xiqi2@huawei.com Signed-off-by: Qi Xi Reviewed-by: Zi Yan Cc: Jan Kiszka Cc: Johannes Weiner Cc: Kefeng Wang Cc: Kieran Bingham Cc: Konstantin Taranov Cc: Long Li Cc: Michal Hocko Cc: Nanyong Sun Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm/page_owner: add MR_NEVER to enum migrate_reason and use it for last_migrate_reason

2026-07-29T04:11:50+00:00

The last_migrate_reason field uses -1 as a sentinel value to mean "no migration has happened". Replace the four bare -1 occurrences by adding a proper MR_NEVER member to enum migrate_reason, defining a corresponding "never_migrated" string in the MIGRATE_REASON trace macro, and updating the GDB page_owner script to use MR_NEVER instead of the hardcoded -1 so that lx-dump-page-owner does not incorrectly report unmigrated pages as migrated. No functional change. Link: https://lore.kernel.org/20260714015117.78351-3-ye.liu@linux.dev Signed-off-by: Ye Liu Reviewed-by: Zi Yan Reviewed-by: Vlastimil Babka (SUSE) Cc: Brendan Jackman Cc: Johannes Weiner Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Suren Baghdasaryan Cc: David Hildenbrand (Arm) Signed-off-by: Andrew Morton

Merge tag 'timers-nohz-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

2026-06-15T08:18:52+00:00

Pull NOHZ updates from Thomas Gleixner: - Fix a long standing TOCTOU in get_cpu_sleep_time_us() - Make the CPU offline NOHZ handling more robust by disabling NOHZ on the outgoing CPU early instead of creating unneeded state which needs to be undone. - Unify idle CPU time accounting instead of having two different accounting mechanisms. These two different mechanisms are not really independent, but the different properties can in the worst case cause that gloabl idle time can be observed going backwards. - Consolidate the idle/iowait time retrieval interfaces instead of converting back and forth between them. - Make idle interrupt time accounting more robust. The original code assumes that interrupt time accouting is enabled and therefore stops elapsing idle time while an interrupt is handled in NOHZ dyntick state. That assumption is not correct as interrupt time accounting can be disabled at compile and runtime. - Fix an accounting error between dyntick idle time and dyntick idle steal time. The stolen time is not accounted and therefore idle time becomes inaccurate. The stolen time is now accounted after the fact as there is no way to predict the steal time upfront. * tag 'timers-nohz-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: sched/cputime: Handle dyntick-idle steal time correctly sched/cputime: Handle idle irqtime gracefully sched/cputime: Provide get_cpu_[idle|iowait]_time_us() off-case tick/sched: Consolidate idle time fetching APIs tick/sched: Account tickless idle cputime only when tick is stopped tick/sched: Remove unused fields tick/sched: Move dyntick-idle cputime accounting to cputime code tick/sched: Remove nohz disabled special case in cputime fetch tick/sched: Unify idle cputime accounting s390/time: Prepare to stop elapsing in dynticks-idle powerpc/time: Prepare to stop elapsing in dynticks-idle sched/cputime: Correctly support generic vtime idle time sched/cputime: Remove superfluous and error prone kcpustat_field() parameter sched/idle: Handle offlining first in idle loop tick/sched: Fix TOCTOU in nohz idle time fetch

Merge tag 'irq-core-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

2026-06-15T07:49:41+00:00

Pull interrupt core updates from Thomas Gleixner: - Rework of /proc/interrupt handling: /proc/interrupts was subject to micro optimizations for a long time, but most of the low hanging fruit was left on the table. This rework addresses the major time consuming issues: - Printing a long series of zeros one by one via a format string instead of counting subsequent zeros and emitting a string constant. - Simplify and cache the conditions whether interrupts should be printed - Use a proper iteration over the interrupt descriptor xarray instead of walking and testing one by one. - Provide helper functions for the architecture code to emit the architecture specific counters - Convert the counter structure in x86 to an array, which simplifies the output and add mechanisms to suppress unused architecture interrupts, which just occupy space for nothing. Adopt the new core mechanisms. This adjusts the gdb scripts related to interrupt counter statistics to work with the new mechanisms. - Prevent a string overflow in the /proc/irq/$N/ directory name creation code. * tag 'irq-core-2026-06-13' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: x86/irq: Add missing 's' back to thermal event printout genirq/proc: Speed up /proc/interrupts iteration genirq/proc: Runtime size the chip name genirq: Expose irq_find_desc_at_or_after() in core code genirq: Add rcuref count to struct irq_desc genirq/proc: Increase default interrupt number precision to four genirq: Calculate precision only when required genirq: Cache the condition for /proc/interrupts exposure genirq/manage: Make NMI cleanup RT safe genirq: Expose nr_irqs in core code scripts/gdb: Update x86 interrupts to the array based storage x86/irq: Move IOAPIC misrouted and PIC/APIC error counts into irq_stats x86/irq: Suppress unlikely interrupt stats by default x86/irq: Make irqstats array based genirq/proc: Utilize irq_desc::tot_count to avoid evaluation genirq/proc: Avoid formatting zero counts in /proc/interrupts x86/irq: Optimize interrupts decimals printing genirq/proc: Size interrupt directory names for 10-digit interrupt numbers

tick/sched: Remove unused fields

2026-06-02T19:27:25+00:00

Remove fields after the dyntick-idle cputime migration to scheduler code. Signed-off-by: Frederic Weisbecker Signed-off-by: Thomas Gleixner Tested-by: Shrikanth Hegde Link: https://patch.msgid.link/20260508131647.43868-11-frederic@kernel.org

genirq/proc: Runtime size the chip name

2026-05-26T14:21:15+00:00

The chip name column in the /proc/interrupt output is 8 characters and right aligned, which causes visual clutter due to the fixed length and the alignment. Many interrupt chips, e.g. PCI/MSI[X] have way longer names. Update the length when a chip is assigned to an interrupt and utilize this information for the output. Align it left so all chip names start at the begin of the column. Update the GDB script as well and disentangle the header maze so it actually works with all .config combinations. Signed-off-by: Thomas Gleixner Tested-by: Michael Kelley Reviewed-by: Dmitry Ilvokhin Link: https://patch.msgid.link/20260517194932.085786035@kernel.org

genirq/proc: Increase default interrupt number precision to four

2026-05-26T14:21:14+00:00

Quite some architectures have four character wide acronyms for architecture specific interrupts like IPI, NMI, etc. The default precision of printing the Linux device interrupt numbers is three, which causes quite some code to play games with adding or omitting space after the acronym and the colon in order to keep the per CPU numbers properly aligned. Increase the default number precision to four in the core code and get rid of the space games all over the place. At the same time align all architecture specific descriptor texts left so that they show up in the same column as the interrupt chip names, which makes the output more uniform accross architectures. Fix up the GDB script to this new scheme as well. Signed-off-by: Thomas Gleixner Link: https://patch.msgid.link/20260517194931.839482411@kernel.org

genirq: Expose nr_irqs in core code

2026-05-26T14:21:13+00:00

... to avoid function calls in the core code to retrieve the maximum number of interrupts. Rename it to 'total_nr_irqs' as 'nr_irqs' is too generic and fix up the 'nr_irqs' reference in the related GDB script as well. Signed-off-by: Thomas Gleixner Tested-by: Michael Kelley Reviewed-by: Dmitry Ilvokhin Reviewed-by: Radu Rendec Reviewed-by: Shrikanth Hegde Link: https://patch.msgid.link/20260517194931.522168332@kernel.org

scripts/gdb: Update x86 interrupts to the array based storage

2026-05-26T14:21:13+00:00

x86 changed the interrupt statistics from a struct with individual members to an counter array. It also provides a corresponding info array with the strings for prefix and description and an indicator to skip the entry. Update the already out of sync GDB script to use the counter and the info array, which keeps the GDB script in sync automatically. Signed-off-by: Thomas Gleixner Tested-by: Florian Fainelli Reviewed-by: Florian Fainelli Link: https://patch.msgid.link/20260517194931.442613033@kernel.org