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2025-03-17xtensa: Rely on generic printing of preemption modelSebastian Andrzej Siewior
die() invokes later show_regs() -> show_regs_print_info() which prints the current preemption model. Remove it from the initial line. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Link: https://lore.kernel.org/r/20250314160810.2373416-9-bigeasy@linutronix.de
2025-03-17x86: Rely on generic printing of preemption modelSebastian Andrzej Siewior
After __die_header(), __die_body() is always invoked. There we have show_regs() -> show_regs_print_info() which prints the current preemption model. Remove it from the initial line. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314160810.2373416-8-bigeasy@linutronix.de
2025-03-17s390: Rely on generic printing of preemption modelSebastian Andrzej Siewior
die() invokes later show_regs() -> show_regs_print_info() which prints the current preemption model. Remove it from the initial line. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> Link: https://lore.kernel.org/r/20250314160810.2373416-7-bigeasy@linutronix.de
2025-03-17powerpc: Rely on generic printing of preemption modelSebastian Andrzej Siewior
After the first printk in __die() there is show_regs() -> show_regs_print_info() which prints the current preemption model. Remove the preempion model from the arch code. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20250314160810.2373416-6-bigeasy@linutronix.de
2025-03-17arm64: Rely on generic printing of preemption modelSebastian Andrzej Siewior
__die() invokes later show_regs() -> show_regs_print_info() which prints the current preemption model. Remove it from the initial line. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250314160810.2373416-5-bigeasy@linutronix.de
2025-03-17arm: Rely on generic printing of preemption modelSebastian Andrzej Siewior
__die() invokes later __show_regs() -> show_regs_print_info() which prints the current preemption model. Remove it from the initial line. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk> Link: https://lore.kernel.org/r/20250314160810.2373416-4-bigeasy@linutronix.de
2025-03-17lib/dump_stack: Use preempt_model_str()Sebastian Andrzej Siewior
Use preempt_model_str() to print the current preemption model. Use pr_warn() instead of printk() to pass a loglevel. This makes it part of generic WARN/ BUG traces. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314160810.2373416-3-bigeasy@linutronix.de
2025-03-17perf: Clean up pmu specific dataKan Liang
The pmu specific data is saved in task_struct now. Remove it from event context structure. Remove swap_task_ctx() as well. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314172700.438923-7-kan.liang@linux.intel.com
2025-03-17sched: Add a generic function to return the preemption stringSebastian Andrzej Siewior
The individual architectures often add the preemption model to the begin of the backtrace. This is the case on X86 or ARM64 for the "die" case but not for regular warning. With the addition of DYNAMIC_PREEMPT for PREEMPT_RT we end up with CONFIG_PREEMPT and CONFIG_PREEMPT_RT set simultaneously. That means that everyone who tried to add that piece of information gets it wrong for PREEMPT_RT because PREEMPT is checked first. Provide a generic function which returns the current scheduling model considering LAZY preempt and the current state of PREEMPT_DYNAMIC. The resulting strings are: ┏━━━━━━━━━━━┳━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━┓ ┃ Model ┃ -RT -DYN ┃ +RT -DYN ┃ -RT +DYN ┃ +RT +DYN ┃ ┡━━━━━━━━━━━╇━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━┩ │NONE │ NONE │ n/a │ PREEMPT(none) │ n/a │ ├───────────┼──────────────┼───────────────────┼────────────────────┼───────────────────┤ │VOLUNTARY │ VOLUNTARY │ n/a │ PREEMPT(voluntary) │ n/a │ ├───────────┼──────────────┼───────────────────┼────────────────────┼───────────────────┤ │FULL │ PREEMPT │ PREEMPT_RT │ PREEMPT(full) │ PREEMPT_{RT,full} │ ├───────────┼──────────────┼───────────────────┼────────────────────┼───────────────────┤ │LAZY │ PREEMPT_LAZY │ PREEMPT_{RT,LAZY} │ PREEMPT(lazy) │ PREEMPT_{RT,lazy} │ └───────────┴──────────────┴───────────────────┴────────────────────┴───────────────────┘ [ The dynamic building of the string can lead to an empty string if the function is invoked simultaneously on two CPUs. ] Co-developed-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Signed-off-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Co-developed-by: "Steven Rostedt (Google)" <rostedt@goodmis.org> Signed-off-by: "Steven Rostedt (Google)" <rostedt@goodmis.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> Link: https://lore.kernel.org/r/20250314160810.2373416-2-bigeasy@linutronix.de
2025-03-17perf/x86: Remove swap_task_ctx()Kan Liang
The pmu specific data is saved in task_struct now. It doesn't need to swap between context. Remove swap_task_ctx() support. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314172700.438923-6-kan.liang@linux.intel.com
2025-03-17perf/x86/lbr: Fix shorter LBRs call stacks for the system-wide modeKan Liang
In the system-wide mode, LBR callstacks are shorter in comparison to the per-process mode. LBR MSRs are reset during a context switch in the system-wide mode. For the LBR call stack, the LBRs should be always saved/restored during a context switch. Use the space in task_struct to save/restore the LBR call stack data. For a system-wide event, it's unnecessagy to update the lbr_callstack_users for each threads. Add a variable in x86_pmu to indicate whether the system-wide event is active. Fixes: 76cb2c617f12 ("perf/x86/intel: Save/restore LBR stack during context switch") Reported-by: Andi Kleen <ak@linux.intel.com> Reported-by: Alexey Budankov <alexey.budankov@linux.intel.com> Debugged-by: Alexey Budankov <alexey.budankov@linux.intel.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314172700.438923-5-kan.liang@linux.intel.com
2025-03-17perf: Supply task information to sched_task()Kan Liang
To save/restore LBR call stack data in system-wide mode, the task_struct information is required. Extend the parameters of sched_task() to supply task_struct information. When schedule in, the LBR call stack data for new task will be restored. When schedule out, the LBR call stack data for old task will be saved. Only need to pass the required task_struct information. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314172700.438923-4-kan.liang@linux.intel.com
2025-03-17perf: attach/detach PMU specific dataKan Liang
The LBR call stack data has to be saved/restored during context switch to fix the shorter LBRs call stacks issue in the system-wide mode. Allocate PMU specific data and attach them to the corresponding task_struct during LBR call stack monitoring. When a LBR call stack event is accounted, the perf_ctx_data for the related tasks will be allocated/attached by attach_perf_ctx_data(). When a LBR call stack event is unaccounted, the perf_ctx_data for related tasks will be detached/freed by detach_perf_ctx_data(). The LBR call stack event could be a per-task event or a system-wide event. - For a per-task event, perf only allocates the perf_ctx_data for the current task. If the allocation fails, perf will error out. - For a system-wide event, perf has to allocate the perf_ctx_data for both the existing tasks and the upcoming tasks. The allocation for the existing tasks is done in perf_event_alloc(). If any allocation fails, perf will error out. The allocation for the new tasks will be done in perf_event_fork(). A global reader/writer semaphore, global_ctx_data_rwsem, is added to address the global race. - The perf_ctx_data only be freed by the last LBR call stack event. The number of the per-task events is tracked by refcount of each task. Since the system-wide events impact all tasks, it's not practical to go through the whole task list to update the refcount for each system-wide event. The number of system-wide events is tracked by a global variable global_ctx_data_ref. Suggested-by: "Peter Zijlstra (Intel)" <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314172700.438923-3-kan.liang@linux.intel.com
2025-03-17locking/percpu-rwsem: Add guard supportPeter Zijlstra (Intel)
To simplify the usage of the percpu rw semaphore. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250314172700.438923-2-kan.liang@linux.intel.com
2025-03-17perf: Save PMU specific data in task_structKan Liang
Some PMU specific data has to be saved/restored during context switch, e.g. LBR call stack data. Currently, the data is saved in event context structure, but only for per-process event. For system-wide event, because of missing the LBR call stack data after context switch, LBR callstacks are always shorter in comparison to per-process mode. For example, Per-process mode: $perf record --call-graph lbr -- taskset -c 0 ./tchain_edit - 99.90% 99.86% tchain_edit tchain_edit [.] f3 99.86% _start __libc_start_main generic_start_main main f1 - f2 f3 System-wide mode: $perf record --call-graph lbr -a -- taskset -c 0 ./tchain_edit - 99.88% 99.82% tchain_edit tchain_edit [.] f3 - 62.02% main f1 f2 f3 - 28.83% f1 - f2 f3 - 28.83% f1 - f2 f3 - 8.88% generic_start_main main f1 f2 f3 It isn't practical to simply allocate the data for system-wide event in CPU context structure for all tasks. We have no idea which CPU a task will be scheduled to. The duplicated LBR data has to be maintained on every CPU context structure. That's a huge waste. Otherwise, the LBR data still lost if the task is scheduled to another CPU. Save the pmu specific data in task_struct. The size of pmu specific data is 788 bytes for LBR call stack. Usually, the overall amount of threads doesn't exceed a few thousands. For 10K threads, keeping LBR data would consume additional ~8MB. The additional space will only be allocated during LBR call stack monitoring. It will be released when the monitoring is finished. Furthermore, moving task_ctx_data from perf_event_context to task_struct can reduce complexity and make things clearer. E.g. perf doesn't need to swap task_ctx_data on optimized context switch path. This patch set is just the first step. There could be other optimization/extension on top of this patch set. E.g. for cgroup profiling, perf just needs to save/store the LBR call stack information for tasks in specific cgroup. That could reduce the additional space. Also, the LBR call stack can be available for software events, or allow even debugging use cases, like LBRs on crash later. Because of the alignment requirement of Intel Arch LBR, the Kmem cache is used to allocate the PMU specific data. It's required when child task allocates the space. Save it in struct perf_ctx_data. The refcount in struct perf_ctx_data is used to track the users of pmu specific data. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Alexey Budankov <alexey.budankov@linux.intel.com> Link: https://lore.kernel.org/r/20250314172700.438923-1-kan.liang@linux.intel.com
2025-03-17perf: Extend per event callchain limit to branch stackKan Liang
The commit 97c79a38cd45 ("perf core: Per event callchain limit") introduced a per-event term to allow finer tuning of the depth of callchains to save space. It should be applied to the branch stack as well. For example, autoFDO collections require maximum LBR entries. In the meantime, other system-wide LBR users may only be interested in the latest a few number of LBRs. A per-event LBR depth would save the perf output buffer. The patch simply drops the uninterested branches, but HW still collects the maximum branches. There may be a model-specific optimization that can reduce the HW depth for some cases to reduce the overhead further. But it isn't included in the patch set. Because it's not useful for all cases. For example, ARCH LBR can utilize the PEBS and XSAVE to collect LBRs. The depth should have less impact on the collecting overhead. The model-specific optimization may be implemented later separately. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250310181536.3645382-1-kan.liang@linux.intel.com
2025-03-17x86/sev: Simplify the code by removing unnecessary 'else' statementPeng Hao
No need for an 'else' statement after a 'return'. [ mingo: Clarified the changelog ] Signed-off-by: Peng Hao <flyingpeng@tencent.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org
2025-03-17perf/ring_buffer: Allow the EPOLLRDNORM flag for pollTao Chen
The poll man page says POLLRDNORM is equivalent to POLLIN. For poll(), it seems that if user sets pollfd with POLLRDNORM in userspace, perf_poll will not return until timeout even if perf_output_wakeup called, whereas POLLIN returns. Fixes: 76369139ceb9 ("perf: Split up buffer handling from core code") Signed-off-by: Tao Chen <chen.dylane@linux.dev> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250314030036.2543180-1-chen.dylane@linux.dev
2025-03-17perf/core: Use POLLHUP for pinned events in errorNamhyung Kim
Pinned performance events can enter an error state when they fail to be scheduled in the context due to a failed constraint or some other conflict or condition. In error state these events won't generate any samples anymore and are silently ignored until they are recovered by PERF_EVENT_IOC_ENABLE, or the condition can also change so that they can be scheduled in. Tooling should be allowed to know about the state change, but currently there's no mechanism to notify tooling when events enter an error state. One way to do this is to issue a POLLHUP event to poll(2) to handle this. Reading events in an error state would return 0 (EOF) and it matches to the behavior of POLLHUP according to the man page. Tooling should remove the fd of the event from pollfd after getting POLLHUP, otherwise it'll be returned repeatedly. [ mingo: Clarified the changelog ] Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250317061745.1777584-1-namhyung@kernel.org
2025-03-16mm/page_alloc: fix memory accept before watermarks gets initializedKirill A. Shutemov
Watermarks are initialized during the postcore initcall. Until then, all watermarks are set to zero. This causes cond_accept_memory() to incorrectly skip memory acceptance because a watermark of 0 is always met. This can lead to a premature OOM on boot. To ensure progress, accept one MAX_ORDER page if the watermark is zero. Link: https://lkml.kernel.org/r/20250310082855.2587122-1-kirill.shutemov@linux.intel.com Fixes: dcdfdd40fa82 ("mm: Add support for unaccepted memory") Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Farrah Chen <farrah.chen@intel.com> Reported-by: Farrah Chen <farrah.chen@intel.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: <stable@vger.kernel.org> [6.5+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm: decline to manipulate the refcount on a slab pageMatthew Wilcox (Oracle)
Slab pages now have a refcount of 0, so nobody should be trying to manipulate the refcount on them. Doing so has little effect; the object could be freed and reallocated to a different purpose, although the slab itself would not be until the refcount was put making it behave rather like TYPESAFE_BY_RCU. Unfortunately, __iov_iter_get_pages_alloc() does take a refcount. Fix that to not change the refcount, and make put_page() silently not change the refcount. get_page() warns so that we can fix any other callers that need to be changed. Long-term, networking needs to stop taking a refcount on the pages that it uses and rely on the caller to hold whatever references are necessary to make the memory stable. In the medium term, more page types are going to hav a zero refcount, so we'll want to move get_page() and put_page() out of line. Link: https://lkml.kernel.org/r/20250310143544.1216127-1-willy@infradead.org Fixes: 9aec2fb0fd5e (slab: allocate frozen pages) Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reported-by: Hannes Reinecke <hare@suse.de> Closes: https://lore.kernel.org/all/08c29e4b-2f71-4b6d-8046-27e407214d8c@suse.com/ Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16memcg: drain obj stock on cpu hotplug teardownShakeel Butt
Currently on cpu hotplug teardown, only memcg stock is drained but we need to drain the obj stock as well otherwise we will miss the stats accumulated on the target cpu as well as the nr_bytes cached. The stats include MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B. In addition we are leaking reference to struct obj_cgroup object. Link: https://lkml.kernel.org/r/20250310230934.2913113-1-shakeel.butt@linux.dev Fixes: bf4f059954dc ("mm: memcg/slab: obj_cgroup API") Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm/huge_memory: drop beyond-EOF folios with the right number of refsZi Yan
When an after-split folio is large and needs to be dropped due to EOF, folio_put_refs(folio, folio_nr_pages(folio)) should be used to drop all page cache refs. Otherwise, the folio will not be freed, causing memory leak. This leak would happen on a filesystem with blocksize > page_size and a truncate is performed, where the blocksize makes folios split to >0 order ones, causing truncated folios not being freed. Link: https://lkml.kernel.org/r/20250310155727.472846-1-ziy@nvidia.com Fixes: c010d47f107f ("mm: thp: split huge page to any lower order pages") Signed-off-by: Zi Yan <ziy@nvidia.com> Reported-by: Hugh Dickins <hughd@google.com> Closes: https://lore.kernel.org/all/fcbadb7f-dd3e-21df-f9a7-2853b53183c4@google.com/ Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: David Hildenbrand <david@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Luis Chamberalin <mcgrof@kernel.org> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Pankaj Raghav <p.raghav@samsung.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Yu Zhao <yuzhao@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16selftests/mm: run_vmtests.sh: fix half_ufd_size_MB calculationRafael Aquini
We noticed that uffd-stress test was always failing to run when invoked for the hugetlb profiles on x86_64 systems with a processor count of 64 or bigger: ... # ------------------------------------ # running ./uffd-stress hugetlb 128 32 # ------------------------------------ # ERROR: invalid MiB (errno=9, @uffd-stress.c:459) ... # [FAIL] not ok 3 uffd-stress hugetlb 128 32 # exit=1 ... The problem boils down to how run_vmtests.sh (mis)calculates the size of the region it feeds to uffd-stress. The latter expects to see an amount of MiB while the former is just giving out the number of free hugepages halved down. This measurement discrepancy ends up violating uffd-stress' assertion on number of hugetlb pages allocated per CPU, causing it to bail out with the error above. This commit fixes that issue by adjusting run_vmtests.sh's half_ufd_size_MB calculation so it properly renders the region size in MiB, as expected, while maintaining all of its original constraints in place. Link: https://lkml.kernel.org/r/20250218192251.53243-1-aquini@redhat.com Fixes: 2e47a445d7b3 ("selftests/mm: run_vmtests.sh: fix hugetlb mem size calculation") Signed-off-by: Rafael Aquini <raquini@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm: fix error handling in __filemap_get_folio() with FGP_NOWAITRaphael S. Carvalho
original report: https://lore.kernel.org/all/CAKhLTr1UL3ePTpYjXOx2AJfNk8Ku2EdcEfu+CH1sf3Asr=B-Dw@mail.gmail.com/T/ When doing buffered writes with FGP_NOWAIT, under memory pressure, the system returned ENOMEM despite there being plenty of available memory, to be reclaimed from page cache. The user space used io_uring interface, which in turn submits I/O with FGP_NOWAIT (the fast path). retsnoop pointed to iomap_get_folio: 00:34:16.180612 -> 00:34:16.180651 TID/PID 253786/253721 (reactor-1/combined_tests): entry_SYSCALL_64_after_hwframe+0x76 do_syscall_64+0x82 __do_sys_io_uring_enter+0x265 io_submit_sqes+0x209 io_issue_sqe+0x5b io_write+0xdd xfs_file_buffered_write+0x84 iomap_file_buffered_write+0x1a6 32us [-ENOMEM] iomap_write_begin+0x408 iter=&{.inode=0xffff8c67aa031138,.len=4096,.flags=33,.iomap={.addr=0xffffffffffffffff,.length=4096,.type=1,.flags=3,.bdev=0x… pos=0 len=4096 foliop=0xffffb32c296b7b80 ! 4us [-ENOMEM] iomap_get_folio iter=&{.inode=0xffff8c67aa031138,.len=4096,.flags=33,.iomap={.addr=0xffffffffffffffff,.length=4096,.type=1,.flags=3,.bdev=0x… pos=0 len=4096 This is likely a regression caused by 66dabbb65d67 ("mm: return an ERR_PTR from __filemap_get_folio"), which moved error handling from io_map_get_folio() to __filemap_get_folio(), but broke FGP_NOWAIT handling, so ENOMEM is being escaped to user space. Had it correctly returned -EAGAIN with NOWAIT, either io_uring or user space itself would be able to retry the request. It's not enough to patch io_uring since the iomap interface is the one responsible for it, and pwritev2(RWF_NOWAIT) and AIO interfaces must return the proper error too. The patch was tested with scylladb test suite (its original reproducer), and the tests all pass now when memory is pressured. Link: https://lkml.kernel.org/r/20250224143700.23035-1-raphaelsc@scylladb.com Fixes: 66dabbb65d67 ("mm: return an ERR_PTR from __filemap_get_folio") Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm: memcontrol: fix swap counter leak from offline cgroupMuchun Song
Commit 6769183166b3 removed the parameter of id from swap_cgroup_record() and get the memcg id from mem_cgroup_id(folio_memcg(folio)). However, the caller of it may update a different memcg's counter instead of folio_memcg(folio). E.g. in the caller of mem_cgroup_swapout(), @swap_memcg could be different with @memcg and update the counter of @swap_memcg, but swap_cgroup_record() records the wrong memcg's ID. When it is uncharged from __mem_cgroup_uncharge_swap(), the swap counter will leak since the wrong recorded ID. Fix it by bringing the parameter of id back. Link: https://lkml.kernel.org/r/20250306023133.44838-1-songmuchun@bytedance.com Fixes: 6769183166b3 ("mm/swap_cgroup: decouple swap cgroup recording and clearing") Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Kairui Song <kasong@tencent.com> Cc: Chris Li <chrisl@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm/vma: do not register private-anon mappings with khugepaged during mmapDev Jain
We already are registering private-anon VMAs with khugepaged during fault time, in do_huge_pmd_anonymous_page(). Commit "register suitable readonly file vmas for khugepaged" moved the khugepaged registration logic from shmem_mmap to the generic mmap path. The userspace-visible effect should be this: khugepaged will unnecessarily scan mm's which haven't yet faulted in. Note that it won't actually collapse because all PTEs are none. Now that I think about it, the mm is going to have a file VMA anyways during fork+exec, so the mm already gets registered during mmap due to the non-anon case (I *think*), so at least one of either the mmap registration or fault-time registration is redundant. Make this logic specific for non-anon mappings. Link: https://lkml.kernel.org/r/20250306063037.16299-1-dev.jain@arm.com Fixes: 613bec092fe7 ("mm: mmap: register suitable readonly file vmas for khugepaged") Signed-off-by: Dev Jain <dev.jain@arm.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jann Horn <jannh@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yang Shi <yang@os.amperecomputing.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16squashfs: fix invalid pointer dereference in squashfs_cache_deleteZhiyu Zhang
When mounting a squashfs fails, squashfs_cache_init() may return an error pointer (e.g., -ENOMEM) instead of NULL. However, squashfs_cache_delete() only checks for a NULL cache, and attempts to dereference the invalid pointer. This leads to a kernel crash (BUG: unable to handle kernel paging request in squashfs_cache_delete). This patch fixes the issue by checking IS_ERR(cache) before accessing it. Link: https://lkml.kernel.org/r/20250306132855.2030-1-zhiyuzhang999@gmail.com Fixes: 49ff29240ebb ("squashfs: make squashfs_cache_init() return ERR_PTR(-ENOMEM)") Signed-off-by: Zhiyu Zhang <zhiyuzhang999@gmail.com> Reported-by: Zhiyu Zhang <zhiyuzhang999@gmail.com> Closes: https://lore.kernel.org/linux-fsdevel/CALf2hKvaq8B4u5yfrE+BYt7aNguao99mfWxHngA+=o5hwzjdOg@mail.gmail.com/ Tested-by: Zhiyu Zhang <zhiyuzhang999@gmail.com> Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm/migrate: fix shmem xarray update during migrationZi Yan
A shmem folio can be either in page cache or in swap cache, but not at the same time. Namely, once it is in swap cache, folio->mapping should be NULL, and the folio is no longer in a shmem mapping. In __folio_migrate_mapping(), to determine the number of xarray entries to update, folio_test_swapbacked() is used, but that conflates shmem in page cache case and shmem in swap cache case. It leads to xarray multi-index entry corruption, since it turns a sibling entry to a normal entry during xas_store() (see [1] for a userspace reproduction). Fix it by only using folio_test_swapcache() to determine whether xarray is storing swap cache entries or not to choose the right number of xarray entries to update. [1] https://lore.kernel.org/linux-mm/Z8idPCkaJW1IChjT@casper.infradead.org/ Note: In __split_huge_page(), folio_test_anon() && folio_test_swapcache() is used to get swap_cache address space, but that ignores the shmem folio in swap cache case. It could lead to NULL pointer dereferencing when a in-swap-cache shmem folio is split at __xa_store(), since !folio_test_anon() is true and folio->mapping is NULL. But fortunately, its caller split_huge_page_to_list_to_order() bails out early with EBUSY when folio->mapping is NULL. So no need to take care of it here. Link: https://lkml.kernel.org/r/20250305200403.2822855-1-ziy@nvidia.com Fixes: fc346d0a70a1 ("mm: migrate high-order folios in swap cache correctly") Signed-off-by: Zi Yan <ziy@nvidia.com> Reported-by: Liu Shixin <liushixin2@huawei.com> Closes: https://lore.kernel.org/all/28546fb4-5210-bf75-16d6-43e1f8646080@huawei.com/ Suggested-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Charan Teja Kalla <quic_charante@quicinc.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm/hugetlb: fix surplus pages in dissolve_free_huge_page()Jinjiang Tu
In dissolve_free_huge_page(), free huge pages are dissolved without adjusting surplus count. However, free huge pages may be accounted as surplus pages, and will lead to wrong surplus count. I reproduce this issue on qemu. The steps are: 1) Node1 is memory-less at first. Hot-add memory to node1 by executing the two commands in qemu monitor: object_add memory-backend-ram,id=mem1,size=1G device_add pc-dimm,id=dimm1,memdev=mem1,node=1 2) online one memory block of Node1 with： echo online_movable > /sys/devices/system/node/node1/memoryX/state 3) create 64 huge pages for node1 4) run a program to reserve (don't consume) all the huge pages 5) echo 0 > nr_huge_pages for node1. After this step, free huge pages in Node1 are surplus. 6) create 80 huge pages for node0 7) offline memory of node1, The memory range to offline contains the free surplus huge pages created in step3) ~ step5) echo offline > /sys/devices/system/node/node1/memoryX/state 8) kill the program in step 4) The result: Node0 Node1 total 80 0 free 80 0 surplus 0 61 To fix it, adjust surplus when destroying huge pages if the node has surplus pages in dissolve_free_hugetlb_folio(). The result with this patch: Node0 Node1 total 80 0 free 80 0 surplus 0 0 Link: https://lkml.kernel.org/r/20250304132106.2872754-1-tujinjiang@huawei.com Fixes: c8721bbbdd36 ("mm: memory-hotplug: enable memory hotplug to handle hugepage") Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Oscar Salvador <osalvador@suse.de> Cc: Jinjiang Tu <tujinjiang@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm/damon/core: initialize damos->walk_completed in damon_new_scheme()SeongJae Park
The function for allocating and initialize a 'struct damos' object, damon_new_scheme(), is not initializing damos->walk_completed field. Only damos_walk_complete() is setting the field. Hence the field will be eventually set and used correctly from second damos_walk() call for the scheme. But the first damos_walk() could mistakenly not walk on the regions. Actually, a common usage of DAMOS for taking an access pattern snapshot is installing a monitoring-purpose DAMOS scheme, doing damos_walk() to retrieve the snapshot, and then removing the scheme. DAMON user-space tool (damo) also gets runtime snapshot in the way. Hence the problem can continuously happen in such use cases. Initialize it properly in the allocation function. Link: https://lkml.kernel.org/r/20250228174450.41472-1-sj@kernel.org Fixes: bf0eaba0ff9c ("mm/damon/core: implement damos_walk()") Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16mm/damon: respect core layer filters' allowance decision on ops layerSeongJae Park
Filtering decisions are made in filters evaluation order. Once a decision is made by a filter, filters that scheduled to be evaluated after the decision-made filter should just respect it. This is the intended and documented behavior. Since core layer-handled filters are evaluated before operations layer-handled filters, decisions made on core layer should respected by ops layer. In case of reject filters, the decision is respected, since core layer-rejected regions are not passed to ops layer. But in case of allow filters, ops layer filters don't know if the region has passed to them because it was allowed by core filters or just because it didn't match to any core layer. The current wrong implementation assumes it was due to not matched by any core filters. As a reuslt, the decision is not respected. Pass the missing information to ops layer using a new filed in 'struct damos', and make the ops layer filters respect it. Link: https://lkml.kernel.org/r/20250228175336.42781-1-sj@kernel.org Fixes: 491fee286e56 ("mm/damon/core: support damos_filter->allow") Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16filemap: move prefaulting out of hot write pathDave Hansen
There is a generic anti-pattern that shows up in the VFS and several filesystems where the hot write paths touch userspace twice when they could get away with doing it once. Dave Chinner suggested that they should all be fixed up[1]. I agree[2]. But, the series to do that fixup spans a bunch of filesystems and a lot of people. This patch fixes common code that absolutely everyone uses. It has measurable performance benefits[3]. I think this patch can go in and not be held up by the others. I will post them separately to their separate maintainers for consideration. But, honestly, I'm not going to lose any sleep if the maintainers don't pick those up. 1. https://lore.kernel.org/all/Z5f-x278Z3wTIugL@dread.disaster.area/ 2. https://lore.kernel.org/all/20250129181749.C229F6F3@davehans-spike.ostc.intel.com/ 3. https://lore.kernel.org/all/202502121529.d62a409e-lkp@intel.com/ This patch: There is a bit of a sordid history here. I originally wrote 998ef75ddb57 ("fs: do not prefault sys_write() user buffer pages") to fix a performance issue that showed up on early SMAP hardware. But that was reverted with 00a3d660cbac because it exposed an underlying filesystem bug. This is a reimplementation of the original commit along with some simplification and comment improvements. The basic problem is that the generic write path has two userspace accesses: one to prefault the write source buffer and then another to perform the actual write. On x86, this means an extra STAC/CLAC pair. These are relatively expensive instructions because they function as barriers. Keep the prefaulting behavior but move it into the slow path that gets run when the write did not make any progress. This avoids livelocks that can happen when the write's source and destination target the same folio. Contrary to the existing comments, the fault-in does not prevent deadlocks. That's accomplished by using an "atomic" usercopy that disables page faults. The end result is that the generic write fast path now touches userspace once instead of twice. 0day has shown some improvements on a couple of microbenchmarks: https://lore.kernel.org/all/202502121529.d62a409e-lkp@intel.com/ Link: https://lkml.kernel.org/r/20250228203722.CAEB63AC@davehans-spike.ostc.intel.com Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/yxyuijjfd6yknryji2q64j3keq2ygw6ca6fs5jwyolklzvo45s@4u63qqqyosy2/ Cc: Ted Ts'o <tytso@mit.edu> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16proc: fix UAF in proc_get_inode()Ye Bin
Fix race between rmmod and /proc/XXX's inode instantiation. The bug is that pde->proc_ops don't belong to /proc, it belongs to a module, therefore dereferencing it after /proc entry has been registered is a bug unless use_pde/unuse_pde() pair has been used. use_pde/unuse_pde can be avoided (2 atomic ops!) because pde->proc_ops never changes so information necessary for inode instantiation can be saved _before_ proc_register() in PDE itself and used later, avoiding pde->proc_ops->... dereference. rmmod lookup sys_delete_module proc_lookup_de pde_get(de); proc_get_inode(dir->i_sb, de); mod->exit() proc_remove remove_proc_subtree proc_entry_rundown(de); free_module(mod); if (S_ISREG(inode->i_mode)) if (de->proc_ops->proc_read_iter) --> As module is already freed, will trigger UAF BUG: unable to handle page fault for address: fffffbfff80a702b PGD 817fc4067 P4D 817fc4067 PUD 817fc0067 PMD 102ef4067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 26 UID: 0 PID: 2667 Comm: ls Tainted: G Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:proc_get_inode+0x302/0x6e0 RSP: 0018:ffff88811c837998 EFLAGS: 00010a06 RAX: dffffc0000000000 RBX: ffffffffc0538140 RCX: 0000000000000007 RDX: 1ffffffff80a702b RSI: 0000000000000001 RDI: ffffffffc0538158 RBP: ffff8881299a6000 R08: 0000000067bbe1e5 R09: 1ffff11023906f20 R10: ffffffffb560ca07 R11: ffffffffb2b43a58 R12: ffff888105bb78f0 R13: ffff888100518048 R14: ffff8881299a6004 R15: 0000000000000001 FS: 00007f95b9686840(0000) GS:ffff8883af100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffbfff80a702b CR3: 0000000117dd2000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> proc_lookup_de+0x11f/0x2e0 __lookup_slow+0x188/0x350 walk_component+0x2ab/0x4f0 path_lookupat+0x120/0x660 filename_lookup+0x1ce/0x560 vfs_statx+0xac/0x150 __do_sys_newstat+0x96/0x110 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e [adobriyan@gmail.com: don't do 2 atomic ops on the common path] Link: https://lkml.kernel.org/r/3d25ded0-1739-447e-812b-e34da7990dcf@p183 Fixes: 778f3dd5a13c ("Fix procfs compat_ioctl regression") Signed-off-by: Ye Bin <yebin10@huawei.com> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: David S. Miller <davem@davemloft.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-16Linux 6.14-rc7v6.14-rc7Linus Torvalds
2025-03-16Merge tag 'media/v6.14-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media fix from Mauro Carvalho Chehab: "rtl2832 driver regression fix" * tag 'media/v6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: media: rtl2832_sdr: assign vb2 lock before vb2_queue_init
2025-03-16Merge tag 'i2c-for-6.14-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c fixes from Wolfram Sang: - omap: fix irq ACKS to avoid irq storming and system hang - ali1535, ali15x3, sis630: fix error path at probe exit * tag 'i2c-for-6.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: sis630: Fix an error handling path in sis630_probe() i2c: ali15x3: Fix an error handling path in ali15x3_probe() i2c: ali1535: Fix an error handling path in ali1535_probe() i2c: omap: fix IRQ storms
2025-03-16Merge tag 'trace-v6.14-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fix from Steven Rostedt: "Fix ref count of trace_array in error path of histogram file open Tracing instances have a ref count to keep them around while files within their directories are open. This prevents them from being deleted while they are used. The histogram code had some files that needed to take the ref count and that was added, but the error paths did not decrement the ref counts. This caused the instances from ever being removed if a histogram file failed to open due to some error" * tag 'trace-v6.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Correct the refcount if the hist/hist_debug file fails to open
2025-03-16perf/core: Use sysfs_emit() instead of scnprintf()XieLudan
Follow the advice in Documentation/filesystems/sysfs.rst: "- show() should only use sysfs_emit() or sysfs_emit_at() when formatting the value to be returned to user space." No change in functionality intended. [ mingo: Updated the changelog ] Signed-off-by: XieLudan <xie.ludan@zte.com.cn> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20250315141738452lXIH39UJAXlCmcATCzcBv@zte.com.cn
2025-03-15Merge tag 'usb-6.14-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here are some small USB and Thunderbolt driver fixes and new usb-serial device ids. Included in here are: - new usb-serial device ids - typec driver bugfix - thunderbolt driver resume bugfix All of these have been in linux-next with no reported issues" * tag 'usb-6.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: usb: typec: tcpm: fix state transition for SNK_WAIT_CAPABILITIES state in run_state_machine() USB: serial: ftdi_sio: add support for Altera USB Blaster 3 thunderbolt: Prevent use-after-free in resume from hibernate USB: serial: option: fix Telit Cinterion FE990A name USB: serial: option: add Telit Cinterion FE990B compositions USB: serial: option: match on interface class for Telit FN990B
2025-03-15Merge tag 'input-for-v6.14-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: - several new device IDs added to xpad game controller driver - support for imagis IST3038H variant of chip added to imagis touch controller driver - a fix for GPIO allocation for ads7846 touch controller driver - a fix for iqs7222 driver to properly support status register - a fix for goodix-berlin touch controller driver to use the right name for the regulator - more i8042 quirks to better handle several old Clevo devices. * tag 'input-for-v6.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: MAINTAINERS: Remove myself from the goodix touchscreen maintainers Input: iqs7222 - preserve system status register Input: i8042 - swap old quirk combination with new quirk for more devices Input: i8042 - swap old quirk combination with new quirk for several devices Input: i8042 - add required quirks for missing old boardnames Input: i8042 - swap old quirk combination with new quirk for NHxxRZQ Input: xpad - rename QH controller to Legion Go S Input: xpad - add support for TECNO Pocket Go Input: xpad - add support for ZOTAC Gaming Zone Input: goodix-berlin - fix vddio regulator references Input: goodix-berlin - fix comment referencing wrong regulator Input: imagis - add support for imagis IST3038H dt-bindings: input/touchscreen: imagis: add compatible for ist3038h Input: xpad - add multiple supported devices Input: xpad - add 8BitDo SN30 Pro, Hyperkin X91 and Gamesir G7 SE controllers Input: ads7846 - fix gpiod allocation Input: wdt87xx_i2c - fix compiler warning
2025-03-15Merge tag 'rust-fixes-6.14-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux Pull rust fixes from Miguel Ojeda: "Toolchain and infrastructure: - Disallow BTF generation with Rust + LTO - Improve rust-analyzer support 'kernel' crate: - 'init' module: remove 'Zeroable' implementation for a couple types that should not have it - 'alloc' module: fix macOS failure in host test by satisfying POSIX alignment requirement - Add missing '\n's to 'pr_*!()' calls And a couple other minor cleanups" * tag 'rust-fixes-6.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: scripts: generate_rust_analyzer: add uapi crate scripts: generate_rust_analyzer: add missing include_dirs scripts: generate_rust_analyzer: add missing macros deps rust: Disallow BTF generation with Rust + LTO rust: task: fix `SAFETY` comment in `Task::wake_up` rust: workqueue: add missing newline to pr_info! examples rust: sync: add missing newline in locked_by log example rust: init: add missing newline to pr_info! calls rust: error: add missing newline to pr_warn! calls rust: docs: add missing newline to printing macro examples rust: alloc: satisfy POSIX alignment requirement rust: init: fix `Zeroable` implementation for `Option<NonNull<T>>` and `Option<KBox<T>>` rust: remove leftover mentions of the `alloc` crate
2025-03-15Merge tag 'fsnotify_for_v6.14-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify reverts from Jan Kara: "Syzbot has found out that fsnotify HSM events generated on page fault can be generated while we already hold freeze protection for the filesystem (when you do buffered write from a buffer which is mmapped file on the same filesystem) which violates expectations for HSM events and could lead to deadlocks of HSM clients with filesystem freezing. Since it's quite late in the cycle we've decided to revert changes implementing HSM events on page fault for now and instead just generate one event for the whole range on mmap(2) so that HSM client can fetch the data at that moment" * tag 'fsnotify_for_v6.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: Revert "fanotify: disable readahead if we have pre-content watches" Revert "mm: don't allow huge faults for files with pre content watches" Revert "fsnotify: generate pre-content permission event on page fault" Revert "xfs: add pre-content fsnotify hook for DAX faults" Revert "ext4: add pre-content fsnotify hook for DAX faults" fsnotify: add pre-content hooks on mmap()
2025-03-15Revert "sched/core: Reduce cost of sched_move_task when config autogroup"Dietmar Eggemann
This reverts commit eff6c8ce8d4d7faef75f66614dd20bb50595d261. Hazem reported a 30% drop in UnixBench spawn test with commit eff6c8ce8d4d ("sched/core: Reduce cost of sched_move_task when config autogroup") on a m6g.xlarge AWS EC2 instance with 4 vCPUs and 16 GiB RAM (aarch64) (single level MC sched domain): https://lkml.kernel.org/r/20250205151026.13061-1-hagarhem@amazon.com There is an early bail from sched_move_task() if p->sched_task_group is equal to p's 'cpu cgroup' (sched_get_task_group()). E.g. both are pointing to taskgroup '/user.slice/user-1000.slice/session-1.scope' (Ubuntu '22.04.5 LTS'). So in: do_exit() sched_autogroup_exit_task() sched_move_task() if sched_get_task_group(p) == p->sched_task_group return /* p is enqueued */ dequeue_task() \ sched_change_group() | task_change_group_fair() | detach_task_cfs_rq() | (1) set_task_rq() | attach_task_cfs_rq() | enqueue_task() / (1) isn't called for p anymore. Turns out that the regression is related to sgs->group_util in group_is_overloaded() and group_has_capacity(). If (1) isn't called for all the 'spawn' tasks then sgs->group_util is ~900 and sgs->group_capacity = 1024 (single CPU sched domain) and this leads to group_is_overloaded() returning true (2) and group_has_capacity() false (3) much more often compared to the case when (1) is called. I.e. there are much more cases of 'group_is_overloaded' and 'group_fully_busy' in WF_FORK wakeup sched_balance_find_dst_cpu() which then returns much more often a CPU != smp_processor_id() (5). This isn't good for these extremely short running tasks (FORK + EXIT) and also involves calling sched_balance_find_dst_group_cpu() unnecessary (single CPU sched domain). Instead if (1) is called for 'p->flags & PF_EXITING' then the path (4),(6) is taken much more often. select_task_rq_fair(..., wake_flags = WF_FORK) cpu = smp_processor_id() new_cpu = sched_balance_find_dst_cpu(..., cpu, ...) group = sched_balance_find_dst_group(..., cpu) do { update_sg_wakeup_stats() sgs->group_type = group_classify() if group_is_overloaded() (2) return group_overloaded if !group_has_capacity() (3) return group_fully_busy return group_has_spare (4) } while group if local_sgs.group_type > idlest_sgs.group_type return idlest (5) case group_has_spare: if local_sgs.idle_cpus >= idlest_sgs.idle_cpus return NULL (6) Unixbench Tests './Run -c 4 spawn' on: (a) VM AWS instance (m7gd.16xlarge) with v6.13 ('maxcpus=4 nr_cpus=4') and Ubuntu 22.04.5 LTS (aarch64). Shell & test run in '/user.slice/user-1000.slice/session-1.scope'. w/o patch w/ patch 21005 27120 (b) i7-13700K with tip/sched/core ('nosmt maxcpus=8 nr_cpus=8') and Ubuntu 22.04.5 LTS (x86_64). Shell & test run in '/A'. w/o patch w/ patch 67675 88806 CONFIG_SCHED_AUTOGROUP=y & /sys/proc/kernel/sched_autogroup_enabled equal 0 or 1. Reported-by: Hazem Mohamed Abuelfotoh <abuehaze@amazon.com> Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Tested-by: Hagar Hemdan <hagarhem@amazon.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250314151345.275739-1-dietmar.eggemann@arm.com
2025-03-15sched/uclamp: Optimize sched_uclamp_used static key enablingXuewen Yan
Repeat calls of static_branch_enable() to an already enabled static key introduce overhead, because it calls cpus_read_lock(). Users may frequently set the uclamp value of tasks, triggering the repeat enabling of the sched_uclamp_used static key. Optimize this and avoid repeat calls to static_branch_enable() by checking whether it's enabled already. [ mingo: Rewrote the changelog for legibility ] Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Christian Loehle <christian.loehle@arm.com> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20250219093747.2612-2-xuewen.yan@unisoc.com
2025-03-15sched/uclamp: Use the uclamp_is_used() helper instead of open-coding itXuewen Yan
Don't open-code static_branch_unlikely(&sched_uclamp_used), we have the uclamp_is_used() wrapper around it. [ mingo: Clean up the changelog ] Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Hongyan Xia <hongyan.xia2@arm.com> Reviewed-by: Christian Loehle <christian.loehle@arm.com> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20250219093747.2612-1-xuewen.yan@unisoc.com
2025-03-15Merge tag 'i2c-host-fixes-6.14-rc7' of ↵Wolfram Sang
git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-current i2c-host-fixes for v6.14-rc7 - omap: fixed irq ACKS to avoid irq storming and system hang. - ali1535, ali15x3, sis630: fixed error path at probe exit.
2025-03-14Merge tag 'v6.14-rc6-smb3-server-fixes' of git://git.samba.org/ksmbdLinus Torvalds
Pull smb server fixes from Steve French: - Two fixes for oplock break/lease races * tag 'v6.14-rc6-smb3-server-fixes' of git://git.samba.org/ksmbd: ksmbd: prevent connection release during oplock break notification ksmbd: fix use-after-free in ksmbd_free_work_struct
2025-03-14Merge tag 'v6.14-rc6-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull smb client fixes from Steve French: "Six smb3 client fixes, all also for stable" * tag 'v6.14-rc6-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: smb: client: Fix match_session bug preventing session reuse cifs: Fix integer overflow while processing closetimeo mount option cifs: Fix integer overflow while processing actimeo mount option cifs: Fix integer overflow while processing acdirmax mount option cifs: Fix integer overflow while processing acregmax mount option smb: client: fix regression with guest option
2025-03-14Merge tag 'bcachefs-2025-03-14.2' of git://evilpiepirate.org/bcachefsLinus Torvalds
Pull another bcachefs hotfix from Kent Overstreet: - fix 32 bit build breakage * tag 'bcachefs-2025-03-14.2' of git://evilpiepirate.org/bcachefs: bcachefs: fix build on 32 bit in get_random_u64_below()
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-01 21:53:57 +0000