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2025-05-12Documentation: add documentation for KHOAlexander Graf
With KHO in place, let's add documentation that describes what it is and how to use it. Link: https://lkml.kernel.org/r/20250509074635.3187114-17-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12mm: add max swappiness arg to lru_gen for anonymous memory onlyZhongkun He
The MGLRU already supports reclaiming only from anonymous memory via the /sys/kernel/debug/lru_gen interface. Now, memory.reclaim also supports the swappiness=max parameter to enable reclaiming solely from anonymous memory. To unify the semantics of proactive reclaiming from anonymous folios, the max parameter is introduced. [hezhongkun.hzk@bytedance.com: use strcmp instead of strncmp, if swappiness is not set, use the default value] Link: https://lkml.kernel.org/r/20250507071057.3184240-1-hezhongkun.hzk@bytedance.com [akpm@linux-foundation.org: tweak coding style] Link: https://lkml.kernel.org/r/65181f7745d657d664d833c26d8a94cae40538b9.1745225696.git.hezhongkun.hzk@bytedance.com Signed-off-by: Zhongkun He <hezhongkun.hzk@bytedance.com> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Yosry Ahmed <yosry.ahmed@linux.dev> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12mm: add swappiness=max arg to memory.reclaim for only anon reclaimZhongkun He
Patch series "add max arg to swappiness in memory.reclaim and lru_gen", v4. This patchset adds max arg to swappiness in memory.reclaim and lru_gen for anon only proactive memory reclaim. With commit <68cd9050d871> ("mm: add swappiness= arg to memory.reclaim") we can submit an additional swappiness=<val> argument to memory.reclaim. It is very useful because we can dynamically adjust the reclamation ratio based on the anonymous folios and file folios of each cgroup. For example,when swappiness is set to 0, we only reclaim from file folios. But we can not relciam memory just from anon folios. This patchset introduces a new macro, SWAPPINESS_ANON_ONLY, defined as MAX_SWAPPINESS + 1, represent the max arg semantics. It specifically indicates that reclamation should occur only from anonymous pages. Patch 1 adds swappiness=max arg to memory.reclaim suggested-by: Yosry Ahmed Patch 2 add more comments for cache_trim_mode from Johannes Weiner in [1]. Patch 3 add max arg to lru_gen for proactive memory reclaim in MGLRU. The MGLRU already supports reclaiming exclusively from anonymous pages. This patch formalizes that behavior by introducing a max parameter to represent the corresponding semantics. Patch 4 using SWAPPINESS_ANON_ONLY in MGLRU Using SWAPPINESS_ANON_ONLY instead of MAX_SWAPPINESS + 1 to indicate reclaiming only from anonymous pages makes the code more readable and explicit Here is the previous discussion: https://lore.kernel.org/all/20250314033350.1156370-1-hezhongkun.hzk@bytedance.com/ https://lore.kernel.org/all/20250312094337.2296278-1-hezhongkun.hzk@bytedance.com/ https://lore.kernel.org/all/20250318135330.3358345-1-hezhongkun.hzk@bytedance.com/ This patch (of 4): With commit <68cd9050d871> ("mm: add swappiness= arg to memory.reclaim") we can submit an additional swappiness=<val> argument to memory.reclaim. It is very useful because we can dynamically adjust the reclamation ratio based on the anonymous folios and file folios of each cgroup. For example,when swappiness is set to 0, we only reclaim from file folios. However,we have also encountered a new issue: when swappiness is set to the MAX_SWAPPINESS, it may still only reclaim file folios. So, we hope to add a new arg 'swappiness=max' in memory.reclaim where proactive memory reclaim only reclaims from anonymous folios when swappiness is set to max. The swappiness semantics from a user perspective remain unchanged. For example, something like this: echo "2M swappiness=max" > /sys/fs/cgroup/memory.reclaim will perform reclaim on the rootcg with a swappiness setting of 'max' (a new mode) regardless of the file folios. Users have a more comprehensive view of the application's memory distribution because there are many metrics available. For example, if we find that a certain cgroup has a large number of inactive anon folios, we can reclaim only those and skip file folios, because with the zram/zswap, the IO tradeoff that cache_trim_mode or other file first logic is making doesn't hold - file refaults will cause IO, whereas anon decompression will not. With this patch, the swappiness argument of memory.reclaim has a new mode 'max', means reclaiming just from anonymous folios both in traditional LRU and MGLRU. Link: https://lkml.kernel.org/r/cover.1745225696.git.hezhongkun.hzk@bytedance.com Link: https://lore.kernel.org/all/20250314141833.GA1316033@cmpxchg.org/ [1] Link: https://lkml.kernel.org/r/519e12b9b1f8c31a01e228c8b4b91a2419684f77.1745225696.git.hezhongkun.hzk@bytedance.com Signed-off-by: Zhongkun He <hezhongkun.hzk@bytedance.com> Suggested-by: Yosry Ahmed <yosry.ahmed@linux.dev> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12memcg-introduce-non-blocking-limit-setting-option-v3Shakeel Butt
add more explanation in doc and commit message on O_NONBLOCK side-effects (Johannes) Link: https://lkml.kernel.org/r/20250506232833.3109790-1-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Greg Thelen <gthelen@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Yosry Ahmed <yosry.ahmed@linux.dev> Cc: Christian Brauner <brauner@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12memcg: introduce non-blocking limit setting optionShakeel Butt
Setting the max and high limits can trigger synchronous reclaim and/or oom-kill if the usage is higher than the given limit. This behavior is fine for newly created cgroups but it can cause issues for the node controller while setting limits for existing cgroups. In our production multi-tenant and overcommitted environment, we are seeing priority inversion when the node controller dynamically adjusts the limits of running jobs of different priorities. Based on the system situation, the node controller may reduce the limits of lower priority jobs and increase the limits of higher priority jobs. However we are seeing node controller getting stuck for long period of time while reclaiming from lower priority jobs while setting their limits and also spends a lot of its own CPU. One of the workaround we are trying is to fork a new process which sets the limit of the lower priority job along with setting an alarm to get itself killed if it get stuck in the reclaim for lower priority job. However we are finding it very unreliable and costly. Either we need a good enough time buffer for the alarm to be delivered after setting limit and potentialy spend a lot of CPU in the reclaim or be unreliable in setting the limit for much shorter but cheaper (less reclaim) alarms. Let's introduce new limit setting option which does not trigger reclaim and/or oom-kill and let the processes in the target cgroup to trigger reclaim and/or throttling and/or oom-kill in their next charge request. This will make the node controller on multi-tenant overcommitted environment much more reliable. Explanation from Johannes on side-effects of O_NONBLOCK limit change: It's usually the allocating tasks inside the group bearing the cost of limit enforcement and reclaim. This allows a (privileged) updater from outside the group to keep that cost in there - instead of having to help, from a context that doesn't necessarily make sense. I suppose the tradeoff with that - and the reason why this was doing sync reclaim in the first place - is that, if the group is idle and not trying to allocate more, it can take indefinitely for the new limit to actually be met. It should be okay in most scenarios in practice. As the capacity is reallocated from group A to B, B will exert pressure on A once it tries to claim it and thereby shrink it down. If A is idle, that shouldn't be hard. If A is running, it's likely to fault/allocate soon-ish and then join the effort. It does leave a (malicious) corner case where A is just busy-hitting its memory to interfere with the clawback. This is comparable to reclaiming memory.low overage from the outside, though, which is an acceptable risk. Users of O_NONBLOCK just need to be aware. Link: https://lkml.kernel.org/r/20250419183545.1982187-1-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Greg Thelen <gthelen@google.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Yosry Ahmed <yosry.ahmed@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12Update Christoph's Email address and make it consistentChristoph Lameter (Ampere)
Use cl@gentwo.org throughout and remove the old email addresses. Link: https://lkml.kernel.org/r/8b962f57-4d98-cbb0-cd82-b6ba456733e8@gentwo.org Signed-off-by: Christoph Lameter <cl@gentwo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12Docs/admin-guide/mm/damon/usage: document 'nid' fileSeongJae Park
Add description of 'nid' file, which is optionally used for specific DAMOS quota goal metrics such as node_mem_{used,free}_bp on DAMON usage document. Link: https://lkml.kernel.org/r/20250420194030.75838-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Yunjeong Mun <yunjeong.mun@sk.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11crash: export PAGE_UNACCEPTED_MAPCOUNT_VALUE to vmcoreinfoZhiquan Li
On Intel TDX guest, unaccepted memory is unusable free memory which is not managed by buddy, until it's accepted by guest. Before that, it cannot be accessed by the first kernel as well as the kexec'ed kernel. The kexec'ed kernel will skip these pages and fill in zero data for the reader of vmcore. The dump tool like makedumpfile creates a page descriptor (size 24 bytes) for each non-free page, including zero data page, but it will not create descriptor for free pages. If it is not able to distinguish these unaccepted pages with zero data pages, a certain amount of space will be wasted in proportion (~1/170). In fact, as a special kind of free page the unaccepted pages should be excluded, like the real free pages. Export the page type PAGE_UNACCEPTED_MAPCOUNT_VALUE to vmcoreinfo, so that dump tool can identify whether a page is unaccepted. [zhiquan1.li@intel.com: fix docs: "Title underline too short" warning] Link: https://lore.kernel.org/all/20240809114854.3745464-5-kirill.shutemov@linux.intel.com/ Link: https://lkml.kernel.org/r/20250405060610.860465-1-zhiquan1.li@intel.com Link: https://lore.kernel.org/all/20240809114854.3745464-5-kirill.shutemov@linux.intel.com/ Link: https://lkml.kernel.org/r/20250403030801.758687-1-zhiquan1.li@intel.com Signed-off-by: Zhiquan Li <zhiquan1.li@intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Zhiquan Li <zhiquan1.li@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11Documentation: zram: update IDLE pages tracking documentationSergey Senozhatsky
Move IDLE pages tracking into a separate chapter because there are multiple features that use (or depend on) it either in built-in variant ("mark all") or in extended variant (ac-time tracking). In addition, recompression doesn't require memory tracking to be enabled in order to be able to perform idle recompression. Link: https://lkml.kernel.org/r/20250416042833.3858827-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Shin Kawamura <kawasin@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regionsAndrei Vagin
Patch series "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions", v2. Introduce the PAGE_IS_GUARD flag in the PAGEMAP_SCAN ioctl to expose information about guard regions. This allows userspace tools, such as CRIU, to detect and handle guard regions. Currently, CRIU utilizes PAGEMAP_SCAN as a more efficient alternative to parsing /proc/pid/pagemap. Without this change, guard regions are incorrectly reported as swap-anon regions, leading CRIU to attempt dumping them and subsequently failing. The series includes updates to the documentation and selftests to reflect the new functionality. This patch (of 3): Introduce the PAGE_IS_GUARD flag in the PAGEMAP_SCAN ioctl to expose information about guard regions. This allows userspace tools, such as CRIU, to detect and handle guard regions. Link: https://lkml.kernel.org/r/20250324065328.107678-1-avagin@google.com Link: https://lkml.kernel.org/r/20250324065328.107678-2-avagin@google.com Signed-off-by: Andrei Vagin <avagin@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11mm/compaction: reduce the difference between low and high watermarksMichal Clapinski
Reduce the diff between low and high watermarks when compaction proactiveness is set to high. This allows users who set the proactiveness really high to have more stable fragmentation score over time. Link: https://lkml.kernel.org/r/20250404111103.1994507-3-mclapinski@google.com Signed-off-by: Michal Clapinski <mclapinski@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11zram: modernize writeback interfaceSergey Senozhatsky
The writeback interface supports a page_index=N parameter which performs writeback of the given page. Since we rarely need to writeback just one single page, the typical use case involves a number of writeback calls, each performing writeback of one page: echo page_index=100 > zram0/writeback ... echo page_index=200 > zram0/writeback echo page_index=500 > zram0/writeback ... echo page_index=700 > zram0/writeback One obvious downside of this is that it increases the number of syscalls. Less obvious, but a significantly more important downside, is that when given only one page to post-process zram cannot perform an optimal target selection. This becomes a critical limitation when writeback_limit is enabled, because under writeback_limit we want to guarantee the highest memory savings hence we first need to writeback pages that release the highest amount of zsmalloc pool memory. This patch adds page_indexes=LOW-HIGH parameter to the writeback interface: echo page_indexes=100-200 page_indexes=500-700 > zram0/writeback This gives zram a chance to apply an optimal target selection strategy on each iteration of the writeback loop. We also now permit multiple page_index parameters per call (previously zram would recognize only one page_index) and a mix or single pages and page ranges: echo page_index=42 page_index=99 page_indexes=100-200 \ page_indexes=500-700 > zram0/writeback Apart from that the patch also unifies parameters passing and resembles other "modern" zram device attributes (e.g. recompression), while the old interface used a mixed scheme: values-less parameters for mode and a key=value format for page_index. We still support the "old" value-less format for compatibility reasons. [senozhatsky@chromium.org: simplify parse_page_index() range checks, per Brian] nk: https://lkml.kernel.org/r/20250404015327.2427684-1-senozhatsky@chromium.org [sozhatsky@chromium.org: fix uninitialized variable in zram_writeback_slots(), per Dan] nk: https://lkml.kernel.org/r/20250409112611.1154282-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20250327015818.4148660-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Richard Chang <richardycc@google.com> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-09x86/its: Add support for RSB stuffing mitigationPawan Gupta
When retpoline mitigation is enabled for spectre-v2, enabling call-depth-tracking and RSB stuffing also mitigates ITS. Add cmdline option indirect_target_selection=stuff to allow enabling RSB stuffing mitigation. When retpoline mitigation is not enabled, =stuff option is ignored, and default mitigation for ITS is deployed. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
2025-05-09x86/its: Add "vmexit" option to skip mitigation on some CPUsPawan Gupta
Ice Lake generation CPUs are not affected by guest/host isolation part of ITS. If a user is only concerned about KVM guests, they can now choose a new cmdline option "vmexit" that will not deploy the ITS mitigation when CPU is not affected by guest/host isolation. This saves the performance overhead of ITS mitigation on Ice Lake gen CPUs. When "vmexit" option selected, if the CPU is affected by ITS guest/host isolation, the default ITS mitigation is deployed. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
2025-05-09x86/its: Enable Indirect Target Selection mitigationPawan Gupta
Indirect Target Selection (ITS) is a bug in some pre-ADL Intel CPUs with eIBRS. It affects prediction of indirect branch and RETs in the lower half of cacheline. Due to ITS such branches may get wrongly predicted to a target of (direct or indirect) branch that is located in the upper half of the cacheline. Scope of impact =============== Guest/host isolation -------------------- When eIBRS is used for guest/host isolation, the indirect branches in the VMM may still be predicted with targets corresponding to branches in the guest. Intra-mode ---------- cBPF or other native gadgets can be used for intra-mode training and disclosure using ITS. User/kernel isolation --------------------- When eIBRS is enabled user/kernel isolation is not impacted. Indirect Branch Prediction Barrier (IBPB) ----------------------------------------- After an IBPB, indirect branches may be predicted with targets corresponding to direct branches which were executed prior to IBPB. This is mitigated by a microcode update. Add cmdline parameter indirect_target_selection=off|on|force to control the mitigation to relocate the affected branches to an ITS-safe thunk i.e. located in the upper half of cacheline. Also add the sysfs reporting. When retpoline mitigation is deployed, ITS safe-thunks are not needed, because retpoline sequence is already ITS-safe. Similarly, when call depth tracking (CDT) mitigation is deployed (retbleed=stuff), ITS safe return thunk is not used, as CDT prevents RSB-underflow. To not overcomplicate things, ITS mitigation is not supported with spectre-v2 lfence;jmp mitigation. Moreover, it is less practical to deploy lfence;jmp mitigation on ITS affected parts anyways. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
2025-05-09Documentation: x86/bugs/its: Add ITS documentationPawan Gupta
Add the admin-guide for Indirect Target Selection (ITS). Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
2025-05-09PM: hibernate: add configurable delay for pm_testZihuan Zhang
Turn the default 5 second test delay for hibernation into a configurable module parameter, so users can determine how long to wait in this pseudo-hibernate state before resuming the system. The configurable delay parameter has been added for suspend, so add an analogous one for hibernation. Example (wait 30 seconds); # echo 30 > /sys/module/hibernate/parameters/pm_test_delay # echo core > /sys/power/pm_test Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20250507063520.419635-1-zhangzihuan@kylinos.cn [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-05-09Documentation: media: Add documentation file c3-isp.rstKeke Li
Add the file 'c3-isp.rst' that documents the c3-isp driver. Signed-off-by: Keke Li <keke.li@amlogic.com> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
2025-05-07xfs: allow sysadmins to specify a maximum atomic write limit at mount timeDarrick J. Wong
Introduce a mount option to allow sysadmins to specify the maximum size of an atomic write. If the filesystem can work with the supplied value, that becomes the new guaranteed maximum. The value mustn't be too big for the existing filesystem geometry (max write size, max AG/rtgroup size). We dynamically recompute the tr_atomic_write transaction reservation based on the given block size, check that the current log size isn't less than the new minimum log size constraints, and set a new maximum. The actual software atomic write max is still computed based off of tr_atomic_ioend the same way it has for the past few commits. Note also that xfs_calc_atomic_write_log_geometry is non-static because mkfs will need that. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: John Garry <john.g.garry@oracle.com> Reviewed-by: John Garry <john.g.garry@oracle.com>
2025-05-02x86/cpu: Add "Old Microcode" docs to hw-vuln toctreeBagas Sanjaya
Sphinx reports missing toctree entry warning: Documentation/admin-guide/hw-vuln/old_microcode.rst: WARNING: document isn't included in any toctree Add entry for "Old Microcode" docs to fix the warning. Fixes: 4e2c719782a847 ("x86/cpu: Help users notice when running old Intel microcode") Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20250502023358.14846-1-bagasdotme%40gmail.com
2025-05-01Documentation: Document the new zoned loop block device driverDamien Le Moal
Introduce the zoned_loop.rst documentation file under admin-guide/blockdev to document the zoned loop block device driver. An overview of the driver is provided and its usage to create and delete zoned devices described. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20250407075222.170336-3-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.15-rc5). No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-30kbuild: require gcc-8 and binutils-2.30Arnd Bergmann
Commit a3e8fe814ad1 ("x86/build: Raise the minimum GCC version to 8.1") raised the minimum compiler version as enforced by Kbuild to gcc-8.1 and clang-15 for x86. This is actually the same gcc version that has been discussed as the minimum for all architectures several times in the past, with little objection. A previous concern was the kernel for SLE15-SP7 needing to be built with gcc-7. As this ended up still using linux-6.4 and there is no plan for an SP8, this is no longer a problem. Change it for all architectures and adjust the documentation accordingly. A few version checks can be removed in the process. The binutils version 2.30 is the lowest version used in combination with gcc-8 on common distros, so use that as the corresponding minimum. Link: https://lore.kernel.org/lkml/20240925150059.3955569-32-ardb+git@google.com/ Link: https://lore.kernel.org/lkml/871q7yxrgv.wl-tiwai@suse.de/ Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2025-04-28docs: namespace: Tweak and reword resource control docJoel Savitz
Fix the document title and reword the phrasing to active voice. Signed-off-by: Joel Savitz <jsavitz@redhat.com> Message-ID: <20250421161723.1138903-1-jsavitz@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2025-04-25docs: media: mgb4: Improve mgb4 driver documentationMartin Tůma
Add some basic info about the HW/driver + contact info. Signed-off-by: Martin Tůma <martin.tuma@digiteqautomotive.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
2025-04-25media: remove STA2x11 media pci driverLukas Bulwahn
With commit dcbb01fbb7ae ("x86/pci: Remove old STA2x11 support"), the STA2X11 Video Input Port driver is not needed and cannot be built anymore. Remove the driver and its reference in media documentation. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
2025-04-24Documentation/admin-guide: Document Thunderbolt/USB4 tunneling eventsAlan Borzeszkowski
Add documentation about the Thunderbolt/USB4 tunneling events to the user’s and administrator’s guide. Signed-off-by: Alan Borzeszkowski <alan.borzeszkowski@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2025-04-22xfs: remove duplicate Zoned Filesystems sections in admin-guideHans Holmberg
Remove the duplicated section and while at it, turn spaces into tabs. Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Fixes: c7b67ddc3c99 ("xfs: document zoned rt specifics in admin-guide") Signed-off-by: Carlos Maiolino <cem@kernel.org>
2025-04-22x86/cpu: Help users notice when running old Intel microcodeDave Hansen
Old microcode is bad for users and for kernel developers. For users, it exposes them to known fixed security and/or functional issues. These obviously rarely result in instant dumpster fires in every environment. But it is as important to keep your microcode up to date as it is to keep your kernel up to date. Old microcode also makes kernels harder to debug. A developer looking at an oops need to consider kernel bugs, known CPU issues and unknown CPU issues as possible causes. If they know the microcode is up to date, they can mostly eliminate known CPU issues as the cause. Make it easier to tell if CPU microcode is out of date. Add a list of released microcode. If the loaded microcode is older than the release, tell users in a place that folks can find it: /sys/devices/system/cpu/vulnerabilities/old_microcode Tell kernel kernel developers about it with the existing taint flag: TAINT_CPU_OUT_OF_SPEC == Discussion == When a user reports a potential kernel issue, it is very common to ask them to reproduce the issue on mainline. Running mainline, they will (independently from the distro) acquire a more up-to-date microcode version list. If their microcode is old, they will get a warning about the taint and kernel developers can take that into consideration when debugging. Just like any other entry in "vulnerabilities/", users are free to make their own assessment of their exposure. == Microcode Revision Discussion == The microcode versions in the table were generated from the Intel microcode git repo: 8ac9378a8487 ("microcode-20241112 Release") which as of this writing lags behind the latest microcode-20250211. It can be argued that the versions that the kernel picks to call "old" should be a revision or two old. Which specific version is picked is less important to me than picking *a* version and enforcing it. This repository contains only microcode versions that Intel has deemed to be OS-loadable. It is quite possible that the BIOS has loaded a newer microcode than the latest in this repo. If this happens, the system is considered to have new microcode, not old. Specifically, the sysfs file and taint flag answer the question: Is the CPU running on the latest OS-loadable microcode, or something even later that the BIOS loaded? In other words, Intel never publishes an authoritative list of CPUs and latest microcode revisions. Until it does, this is the best that Linux can do. Also note that the "intel-ucode-defs.h" file is simple, ugly and has lots of magic numbers. That's on purpose and should allow a single file to be shared across lots of stable kernel regardless of if they have the new "VFM" infrastructure or not. It was generated with a dumb script. == FAQ == Q: Does this tell me if my system is secure or insecure? A: No. It only tells you if your microcode was old when the system booted. Q: Should the kernel warn if the microcode list itself is too old? A: No. New kernels will get new microcode lists, both mainline and stable. The only way to have an old list is to be running an old kernel in which case you have bigger problems. Q: Is this for security or functional issues? A: Both. Q: If a given microcode update only has functional problems but no security issues, will it be considered old? A: Yes. All microcode image versions within a microcode release are treated identically. Intel appears to make security updates without disclosing them in the release notes. Thus, all updates are considered to be security-relevant. Q: Who runs old microcode? A: Anybody with an old distro. This happens all the time inside of Intel where there are lots of weird systems in labs that might not be getting regular distro updates and might also be running rather exotic microcode images. Q: If I update my microcode after booting will it stop saying "Vulnerable"? A: No. Just like all the other vulnerabilies, you need to reboot before the kernel will reassess your vulnerability. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: "Ahmed S. Darwish" <darwi@linutronix.de> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/all/20250421195659.CF426C07%40davehans-spike.ostc.intel.com (cherry picked from commit 9127865b15eb0a1bd05ad7efe29489c44394bdc1)
2025-04-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.15-rc3). No conflicts. Adjacent changes: tools/net/ynl/pyynl/ynl_gen_c.py 4d07bbf2d456 ("tools: ynl-gen: don't declare loop iterator in place") 7e8ba0c7de2b ("tools: ynl: don't use genlmsghdr in classic netlink") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-17xfs: document zoned rt specifics in admin-guideHans Holmberg
Document the lifetime, nolifetime and max_open_zones mount options added for zoned rt file systems. Also add documentation describing the max_open_zones sysfs attribute exposed in /sys/fs/xfs/<dev>/zoned/ Fixes: 4e4d52075577 ("xfs: add the zoned space allocator") Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2025-04-15Documentation: admin-guide: pm: Document intel_idle C1 demotionArtem Bityutskiy
Document the intel_idle driver sysfs file for enabling/disabling C1 demotion. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Link: https://patch.msgid.link/20250317135541.1471754-3-dedekind1@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-04-14cpufreq: editing corrections to cpufreq.rstRandy Dunlap
Change a few words and abbreviations/punctuation. Change one echo command to include a trailing '`'. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: linux-pm@vger.kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250405001447.4039463-1-rdunlap@infradead.org
2025-04-14docs: Disambiguate a pair of rST labelsJames Addison
According to the reStructuredText documentation, internal hyperlink targets[1] are intended to resolve within the current document. Sphinx has a bug that causes internal hyperlinks declared with duplicate names to resolve nondeterministically, producing incorrect documentation. Sphinx does not yet emit a warning when these duplicate target names are declared. To improve the reproducibility and correctness of the HTML documentation, disambiguate two labels both previously titled "submit_improvements". [1] - https://docutils.sourceforge.io/docs/ref/rst/restructuredtext.html#hyperlink-targets Link: https://github.com/sphinx-doc/sphinx/issues/13383 Signed-off-by: James Addison <jay@jp-hosting.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250407195120.331103-2-jvanderwaa@redhat.com
2025-04-14xfs: add tunable threshold parameter for triggering zone GCHans Holmberg
Presently we start garbage collection late - when we start running out of free zones to backfill max_open_zones. This is a reasonable default as it minimizes write amplification. The longer we wait, the more blocks are invalidated and reclaim cost less in terms of blocks to relocate. Starting this late however introduces a risk of GC being outcompeted by user writes. If GC can't keep up, user writes will be forced to wait for free zones with high tail latencies as a result. This is not a problem under normal circumstances, but if fragmentation is bad and user write pressure is high (multiple full-throttle writers) we will "bottom out" of free zones. To mitigate this, introduce a zonegc_low_space tunable that lets the user specify a percentage of how much of the unused space that GC should keep available for writing. A high value will reclaim more of the space occupied by unused blocks, creating a larger buffer against write bursts. This comes at a cost as write amplification is increased. To illustrate this using a sample workload, setting zonegc_low_space to 60% avoids high (500ms) max latencies while increasing write amplification by 15%. Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2025-04-11net: Retire DCCP socket.Kuniyuki Iwashima
DCCP was orphaned in 2021 by commit 054c4610bd05 ("MAINTAINERS: dccp: move Gerrit Renker to CREDITS"), which noted that the last maintainer had been inactive for five years. In recent years, it has become a playground for syzbot, and most changes to DCCP have been odd bug fixes triggered by syzbot. Apart from that, the only changes have been driven by treewide or networking API updates or adjustments related to TCP. Thus, in 2023, we announced we would remove DCCP in 2025 via commit b144fcaf46d4 ("dccp: Print deprecation notice."). Since then, only one individual has contacted the netdev mailing list. [0] There is ongoing research for Multipath DCCP. The repository is hosted on GitHub [1], and development is not taking place through the upstream community. While the repository is published under the GPLv2 license, the scheduling part remains proprietary, with a LICENSE file [2] stating: "This is not Open Source software." The researcher mentioned a plan to address the licensing issue, upstream the patches, and step up as a maintainer, but there has been no further communication since then. Maintaining DCCP for a decade without any real users has become a burden. Therefore, it's time to remove it. Removing DCCP will also provide significant benefits to TCP. It allows us to freely reorganize the layout of struct inet_connection_sock, which is currently shared with DCCP, and optimize it to reduce the number of cachelines accessed in the TCP fast path. Note that we keep DCCP netfilter modules as requested. [3] Link: https://lore.kernel.org/netdev/20230710182253.81446-1-kuniyu@amazon.com/T/#u #[0] Link: https://github.com/telekom/mp-dccp #[1] Link: https://github.com/telekom/mp-dccp/blob/mpdccp_v03_k5.10/net/dccp/non_gpl_scheduler/LICENSE #[2] Link: https://lore.kernel.org/netdev/Z_VQ0KlCRkqYWXa-@calendula/ #[3] Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paul Moore <paul@paul-moore.com> (LSM and SELinux) Acked-by: Casey Schaufler <casey@schaufler-ca.com> Link: https://patch.msgid.link/20250410023921.11307-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-11Documentation: admin-guide: laptops: Add documentation for alienware-wmiKurt Borja
Add driver admin-guide documentation for the alienware-wmi driver. Reviewed-by: Armin Wolf <W_Armin@gmx.de> Signed-off-by: Kurt Borja <kuurtb@gmail.com> Link: https://lore.kernel.org/r/20250329-hwm-v7-11-a14ea39d8a94@gmail.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-04-09Documentation: gpio: document configfs interface for gpio-aggregatorKoichiro Den
Add documentation for the newly added configfs-based interface for GPIO aggregator. Signed-off-by: Koichiro Den <koichiro.den@canonical.com> Link: https://lore.kernel.org/r/20250407043019.4105613-9-koichiro.den@canonical.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-04-09x86/bugs: Add RSB mitigation documentJosh Poimboeuf
Create a document to summarize hard-earned knowledge about RSB-related mitigations, with references, and replace the overly verbose yet incomplete comments with a reference to the document. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/ab73f4659ba697a974759f07befd41ae605e33dd.1744148254.git.jpoimboe@kernel.org
2025-04-09x86/early_printk: Use 'mmio32' for consistency, fix commentsAndy Shevchenko
First of all, using 'mmio' prevents proper implementation of 8-bit accessors. Second, it's simply inconsistent with uart8250 set of options. Rename it to 'mmio32'. While at it, remove rather misleading comment in the documentation. From now on mmio32 is self-explanatory and pciserial supports not only 32-bit MMIO accessors. Also, while at it, fix the comment for the "pciserial" case. The comment seems to be a copy'n'paste error when mentioning "serial" instead of "pciserial" (with double quotes). Fix this. With that, move it upper, so we don't calculate 'buf' twice. Fixes: 3181424aeac2 ("x86/early_printk: Add support for MMIO-based UARTs") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Denis Mukhin <dmukhin@ford.com> Link: https://lore.kernel.org/r/20250407172214.792745-1-andriy.shevchenko@linux.intel.com
2025-04-08sched: Add commadline option for RT_GROUP_SCHED togglingMichal Koutný
Only simple implementation with a static key wrapper, it will be wired in later. Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20250310170442.504716-5-mkoutny@suse.com
2025-04-07fs: Remove aops->writepageMatthew Wilcox (Oracle)
All callers and implementations are now removed, so remove the operation and update the documentation to match. Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org> Link: https://lore.kernel.org/r/20250402150005.2309458-10-willy@infradead.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-04Merge tag 's390-6.15-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Vasily Gorbik: - Fix machine check handler _CIF_MCCK_GUEST bit setting by adding the missing base register for relocated lowcore address - Fix build failure on older linkers by conditionally adding the -no-pie linker option only when it is supported - Fix inaccurate kernel messages in vfio-ap by providing descriptive error notifications for AP queue sharing violations - Fix PCI isolation logic by ensuring non-VF devices correctly return false in zpci_bus_is_isolated_vf() - Fix PCI DMA range map setup by using dma_direct_set_offset() to add a proper sentinel element, preventing potential overruns and translation errors - Cleanup header dependency problems with asm-offsets.c - Add fault info for unexpected low-address protection faults in user mode - Add support for HOTPLUG_SMT, replacing the arch-specific "nosmt" handling with common code handling - Use bitop functions to implement CPU flag helper functions to ensure that bits cannot get lost if modified in different contexts on a CPU - Remove unused machine_flags for the lowcore * tag 's390-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/vfio-ap: Fix no AP queue sharing allowed message written to kernel log s390/pci: Fix dev.dma_range_map missing sentinel element s390/mm: Dump fault info in case of low address protection fault s390/smp: Add support for HOTPLUG_SMT s390: Fix linker error when -no-pie option is unavailable s390/processor: Use bitop functions for cpu flag helper functions s390/asm-offsets: Remove ASM_OFFSETS_C s390/asm-offsets: Include ftrace_regs.h instead of ftrace.h s390/kvm: Split kvm_host header file s390/pci: Fix zpci_bus_is_isolated_vf() for non-VFs s390/lowcore: Remove unused machine_flags s390/entry: Fix setting _CIF_MCCK_GUEST with lowcore relocation
2025-04-04Merge tag 'riscv-for-linus-6.15-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - The sub-architecture selection Kconfig system has been cleaned up, the documentation has been improved, and various detections have been fixed - The vector-related extensions dependencies are now validated when parsing from device tree and in the DT bindings - Misaligned access probing can be overridden via a kernel command-line parameter, along with various fixes to misalign access handling - Support for relocatable !MMU kernels builds - Support for hpge pfnmaps, which should improve TLB utilization - Support for runtime constants, which improves the d_hash() performance - Support for bfloat16, Zicbom, Zaamo, Zalrsc, Zicntr, Zihpm - Various fixes, including: - We were missing a secondary mmu notifier call when flushing the tlb which is required for IOMMU - Fix ftrace panics by saving the registers as expected by ftrace - Fix a couple of stimecmp usage related to cpu hotplug - purgatory_start is now aligned as per the STVEC requirements - A fix for hugetlb when calculating the size of non-present PTEs * tag 'riscv-for-linus-6.15-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (65 commits) riscv: Add norvc after .option arch in runtime const riscv: Make sure toolchain supports zba before using zba instructions riscv/purgatory: 4B align purgatory_start riscv/kexec_file: Handle R_RISCV_64 in purgatory relocator selftests: riscv: fix v_exec_initval_nolibc.c riscv: Fix hugetlb retrieval of number of ptes in case of !present pte riscv: print hartid on bringup riscv: Add norvc after .option arch in runtime const riscv: Remove CONFIG_PAGE_OFFSET riscv: Support CONFIG_RELOCATABLE on riscv32 asm-generic: Always define Elf_Rel and Elf_Rela riscv: Support CONFIG_RELOCATABLE on NOMMU riscv: Allow NOMMU kernels to access all of RAM riscv: Remove duplicate CONFIG_PAGE_OFFSET definition RISC-V: errata: Use medany for relocatable builds dt-bindings: riscv: document vector crypto requirements dt-bindings: riscv: add vector sub-extension dependencies dt-bindings: riscv: d requires f RISC-V: add f & d extension validation checks RISC-V: add vector crypto extension validation checks ...
2025-04-03Merge tag 'trace-ringbuffer-v6.15-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull ring-buffer updates from Steven Rostedt: "Persistent buffer cleanups and simplifications. It was mistaken that the physical memory returned from "reserve_mem" had to be vmap()'d to get to it from a virtual address. But reserve_mem already maps the memory to the virtual address of the kernel so a simple phys_to_virt() can be used to get to the virtual address from the physical memory returned by "reserve_mem". With this new found knowledge, the code can be cleaned up and simplified. - Enforce that the persistent memory is page aligned As the buffers using the persistent memory are all going to be mapped via pages, make sure that the memory given to the tracing infrastructure is page aligned. If it is not, it will print a warning and fail to map the buffer. - Use phys_to_virt() to get the virtual address from reserve_mem Instead of calling vmap() on the physical memory returned from "reserve_mem", use phys_to_virt() instead. As the memory returned by "memmap" or any other means where a physical address is given to the tracing infrastructure, it still needs to be vmap(). Since this memory can never be returned back to the buddy allocator nor should it ever be memmory mapped to user space, flag this buffer and up the ref count. The ref count will keep it from ever being freed, and the flag will prevent it from ever being memory mapped to user space. - Use vmap_page_range() for memmap virtual address mapping For the memmap buffer, instead of allocating an array of struct pages, assigning them to the contiguous phsycial memory and then passing that to vmap(), use vmap_page_range() instead - Replace flush_dcache_folio() with flush_kernel_vmap_range() Instead of calling virt_to_folio() and passing that to flush_dcache_folio(), just call flush_kernel_vmap_range() directly. This also fixes a bug where if a subbuffer was bigger than PAGE_SIZE only the PAGE_SIZE portion would be flushed" * tag 'trace-ringbuffer-v6.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Use flush_kernel_vmap_range() over flush_dcache_folio() tracing: Use vmap_page_range() to map memmap ring buffer tracing: Have reserve_mem use phys_to_virt() and separate from memmap buffer tracing: Enforce the persistent ring buffer to be page aligned
2025-04-02Merge tag 'for-6.15/dm-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mikulas Patocka: - dm-crypt: switch to using the crc32 library - dm-verity, dm-integrity, dm-crypt: documentation improvement - dm-vdo fixes - dm-stripe: enable inline crypto passthrough - dm-integrity: set ti->error on memory allocation failure - dm-bufio: remove unused return value - dm-verity: do forward error correction on metadata I/O errors - dm: fix unconditional IO throttle caused by REQ_PREFLUSH - dm cache: prevent BUG_ON by blocking retries on failed device resumes - dm cache: support shrinking the origin device - dm: restrict dm device size to 2^63-512 bytes - dm-delay: support zoned devices - dm-verity: support block number limits for different ioprio classes - dm-integrity: fix non-constant-time tag verification (security bug) - dm-verity, dm-ebs: fix prefetch-vs-suspend race * tag 'for-6.15/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (27 commits) dm-ebs: fix prefetch-vs-suspend race dm-verity: fix prefetch-vs-suspend race dm-integrity: fix non-constant-time tag verification dm-verity: support block number limits for different ioprio classes dm-delay: support zoned devices dm: restrict dm device size to 2^63-512 bytes dm cache: support shrinking the origin device dm cache: prevent BUG_ON by blocking retries on failed device resumes dm vdo indexer: reorder uds_request to reduce padding dm: fix unconditional IO throttle caused by REQ_PREFLUSH dm vdo: rework processing of loaded refcount byte arrays dm vdo: remove remaining ring references dm-verity: do forward error correction on metadata I/O errors dm-bufio: remove unused return value dm-integrity: set ti->error on memory allocation failure dm: Enable inline crypto passthrough for striped target dm vdo slab-depot: read refcount blocks in large chunks at load time dm vdo vio-pool: allow variable-sized metadata vios dm vdo vio-pool: support pools with multiple data blocks per vio dm vdo vio-pool: add a pool pointer to pooled_vio ...
2025-04-02Merge tag 'fuse-update-6.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Allow connection to server to time out (Joanne Koong) - If server doesn't support creating a hard link, return EPERM rather than ENOSYS (Matt Johnston) - Allow file names longer than 1024 chars (Bernd Schubert) - Fix a possible race if request on io_uring queue is interrupted (Bernd Schubert) - Misc fixes and cleanups * tag 'fuse-update-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: remove unneeded atomic set in uring creation fuse: fix uring race condition for null dereference of fc fuse: Increase FUSE_NAME_MAX to PATH_MAX fuse: Allocate only namelen buf memory in fuse_notify_ fuse: add default_request_timeout and max_request_timeout sysctls fuse: add kernel-enforced timeout option for requests fuse: optmize missing FUSE_LINK support fuse: Return EPERM rather than ENOSYS from link() fuse: removed unused function fuse_uring_create() from header fuse: {io-uring} Fix a possible req cancellation race
2025-04-02tracing: Enforce the persistent ring buffer to be page alignedSteven Rostedt
Enforce that the address and the size of the memory used by the persistent ring buffer is page aligned. Also update the documentation to reflect this requirement. Link: https://lore.kernel.org/all/CAHk-=whUOfVucfJRt7E0AH+GV41ELmS4wJqxHDnui6Giddfkzw@mail.gmail.com/ Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Vincent Donnefort <vdonnefort@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mike Rapoport <rppt@kernel.org> Cc: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/20250402144953.412882844@goodmis.org Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-04-01Merge tag 'mm-nonmm-stable-2025-03-30-18-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - The series "powerpc/crash: use generic crashkernel reservation" from Sourabh Jain changes powerpc's kexec code to use more of the generic layers. - The series "get_maintainer: report subsystem status separately" from Vlastimil Babka makes some long-requested improvements to the get_maintainer output. - The series "ucount: Simplify refcounting with rcuref_t" from Sebastian Siewior cleans up and optimizing the refcounting in the ucount code. - The series "reboot: support runtime configuration of emergency hw_protection action" from Ahmad Fatoum improves the ability for a driver to perform an emergency system shutdown or reboot. - The series "Converge on using secs_to_jiffies() part two" from Easwar Hariharan performs further migrations from msecs_to_jiffies() to secs_to_jiffies(). - The series "lib/interval_tree: add some test cases and cleanup" from Wei Yang permits more userspace testing of kernel library code, adds some more tests and performs some cleanups. - The series "hung_task: Dump the blocking task stacktrace" from Masami Hiramatsu arranges for the hung_task detector to dump the stack of the blocking task and not just that of the blocked task. - The series "resource: Split and use DEFINE_RES*() macros" from Andy Shevchenko provides some cleanups to the resource definition macros. - Plus the usual shower of singleton patches - please see the individual changelogs for details. * tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits) mailmap: consolidate email addresses of Alexander Sverdlin fs/procfs: fix the comment above proc_pid_wchan() relay: use kasprintf() instead of fixed buffer formatting resource: replace open coded variant of DEFINE_RES() resource: replace open coded variants of DEFINE_RES_*_NAMED() resource: replace open coded variant of DEFINE_RES_NAMED_DESC() resource: split DEFINE_RES_NAMED_DESC() out of DEFINE_RES_NAMED() samples: add hung_task detector mutex blocking sample hung_task: show the blocker task if the task is hung on mutex kexec_core: accept unaccepted kexec segments' destination addresses watchdog/perf: optimize bytes copied and remove manual NUL-termination lib/interval_tree: fix the comment of interval_tree_span_iter_next_gap() lib/interval_tree: skip the check before go to the right subtree lib/interval_tree: add test case for span iteration lib/interval_tree: add test case for interval_tree_iter_xxx() helpers lib/rbtree: add random seed lib/rbtree: split tests lib/rbtree: enable userland test suite for rbtree related data structure checkpatch: describe --min-conf-desc-length scripts/gdb/symbols: determine KASLR offset on s390 ...
2025-04-01Merge tag 'mm-stable-2025-03-30-16-52' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - The series "Enable strict percpu address space checks" from Uros Bizjak uses x86 named address space qualifiers to provide compile-time checking of percpu area accesses. This has caused a small amount of fallout - two or three issues were reported. In all cases the calling code was found to be incorrect. - The series "Some cleanup for memcg" from Chen Ridong implements some relatively monir cleanups for the memcontrol code. - The series "mm: fixes for device-exclusive entries (hmm)" from David Hildenbrand fixes a boatload of issues which David found then using device-exclusive PTE entries when THP is enabled. More work is needed, but this makes thins better - our own HMM selftests now succeed. - The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed remove the z3fold and zbud implementations. They have been deprecated for half a year and nobody has complained. - The series "mm: further simplify VMA merge operation" from Lorenzo Stoakes implements numerous simplifications in this area. No runtime effects are anticipated. - The series "mm/madvise: remove redundant mmap_lock operations from process_madvise()" from SeongJae Park rationalizes the locking in the madvise() implementation. Performance gains of 20-25% were observed in one MADV_DONTNEED microbenchmark. - The series "Tiny cleanup and improvements about SWAP code" from Baoquan He contains a number of touchups to issues which Baoquan noticed when working on the swap code. - The series "mm: kmemleak: Usability improvements" from Catalin Marinas implements a couple of improvements to the kmemleak user-visible output. - The series "mm/damon/paddr: fix large folios access and schemes handling" from Usama Arif provides a couple of fixes for DAMON's handling of large folios. - The series "mm/damon/core: fix wrong and/or useless damos_walk() behaviors" from SeongJae Park fixes a few issues with the accuracy of kdamond's walking of DAMON regions. - The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo Stoakes changes the interaction between framebuffer deferred-io and core MM. No functional changes are anticipated - this is preparatory work for the future removal of page structure fields. - The series "mm/damon: add support for hugepage_size DAMOS filter" from Usama Arif adds a DAMOS filter which permits the filtering by huge page sizes. - The series "mm: permit guard regions for file-backed/shmem mappings" from Lorenzo Stoakes extends the guard region feature from its present "anon mappings only" state. The feature now covers shmem and file-backed mappings. - The series "mm: batched unmap lazyfree large folios during reclamation" from Barry Song cleans up and speeds up the unmapping for pte-mapped large folios. - The series "reimplement per-vma lock as a refcount" from Suren Baghdasaryan puts the vm_lock back into the vma. Our reasons for pulling it out were largely bogus and that change made the code more messy. This patchset provides small (0-10%) improvements on one microbenchmark. - The series "Docs/mm/damon: misc DAMOS filters documentation fixes and improves" from SeongJae Park does some maintenance work on the DAMON docs. - The series "hugetlb/CMA improvements for large systems" from Frank van der Linden addresses a pile of issues which have been observed when using CMA on large machines. - The series "mm/damon: introduce DAMOS filter type for unmapped pages" from SeongJae Park enables users of DMAON/DAMOS to filter my the page's mapped/unmapped status. - The series "zsmalloc/zram: there be preemption" from Sergey Senozhatsky teaches zram to run its compression and decompression operations preemptibly. - The series "selftests/mm: Some cleanups from trying to run them" from Brendan Jackman fixes a pile of unrelated issues which Brendan encountered while runnimg our selftests. - The series "fs/proc/task_mmu: add guard region bit to pagemap" from Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to determine whether a particular page is a guard page. - The series "mm, swap: remove swap slot cache" from Kairui Song removes the swap slot cache from the allocation path - it simply wasn't being effective. - The series "mm: cleanups for device-exclusive entries (hmm)" from David Hildenbrand implements a number of unrelated cleanups in this code. - The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual implements a number of preparatoty cleanups to the GENERIC_PTDUMP Kconfig logic. - The series "mm/damon: auto-tune aggregation interval" from SeongJae Park implements a feedback-driven automatic tuning feature for DAMON's aggregation interval tuning. - The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in powerpc, sparc and x86 lazy MMU implementations. Ryan did this in preparation for implementing lazy mmu mode for arm64 to optimize vmalloc. - The series "mm/page_alloc: Some clarifications for migratetype fallback" from Brendan Jackman reworks some commentary to make the code easier to follow. - The series "page_counter cleanup and size reduction" from Shakeel Butt cleans up the page_counter code and fixes a size increase which we accidentally added late last year. - The series "Add a command line option that enables control of how many threads should be used to allocate huge pages" from Thomas Prescher does that. It allows the careful operator to significantly reduce boot time by tuning the parallalization of huge page initialization. - The series "Fix calculations in trace_balance_dirty_pages() for cgwb" from Tang Yizhou fixes the tracing output from the dirty page balancing code. - The series "mm/damon: make allow filters after reject filters useful and intuitive" from SeongJae Park improves the handling of allow and reject filters. Behaviour is made more consistent and the documention is updated accordingly. - The series "Switch zswap to object read/write APIs" from Yosry Ahmed updates zswap to the new object read/write APIs and thus permits the removal of some legacy code from zpool and zsmalloc. - The series "Some trivial cleanups for shmem" from Baolin Wang does as it claims. - The series "fs/dax: Fix ZONE_DEVICE page reference counts" from Alistair Popple regularizes the weird ZONE_DEVICE page refcount handling in DAX, permittig the removal of a number of special-case checks. - The series "refactor mremap and fix bug" from Lorenzo Stoakes is a preparatoty refactoring and cleanup of the mremap() code. - The series "mm: MM owner tracking for large folios (!hugetlb) + CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in which we determine whether a large folio is known to be mapped exclusively into a single MM. - The series "mm/damon: add sysfs dirs for managing DAMOS filters based on handling layers" from SeongJae Park adds a couple of new sysfs directories to ease the management of DAMON/DAMOS filters. - The series "arch, mm: reduce code duplication in mem_init()" from Mike Rapoport consolidates many per-arch implementations of mem_init() into code generic code, where that is practical. - The series "mm/damon/sysfs: commit parameters online via damon_call()" from SeongJae Park continues the cleaning up of sysfs access to DAMON internal data. - The series "mm: page_ext: Introduce new iteration API" from Luiz Capitulino reworks the page_ext initialization to fix a boot-time crash which was observed with an unusual combination of compile and cmdline options. - The series "Buddy allocator like (or non-uniform) folio split" from Zi Yan reworks the code to split a folio into smaller folios. The main benefit is lessened memory consumption: fewer post-split folios are generated. - The series "Minimize xa_node allocation during xarry split" from Zi Yan reduces the number of xarray xa_nodes which are generated during an xarray split. - The series "drivers/base/memory: Two cleanups" from Gavin Shan performs some maintenance work on the drivers/base/memory code. - The series "Add tracepoints for lowmem reserves, watermarks and totalreserve_pages" from Martin Liu adds some more tracepoints to the page allocator code. - The series "mm/madvise: cleanup requests validations and classifications" from SeongJae Park cleans up some warts which SeongJae observed during his earlier madvise work. - The series "mm/hwpoison: Fix regressions in memory failure handling" from Shuai Xue addresses two quite serious regressions which Shuai has observed in the memory-failure implementation. - The series "mm: reliable huge page allocator" from Johannes Weiner makes huge page allocations cheaper and more reliable by reducing fragmentation. - The series "Minor memcg cleanups & prep for memdescs" from Matthew Wilcox is preparatory work for the future implementation of memdescs. - The series "track memory used by balloon drivers" from Nico Pache introduces a way to track memory used by our various balloon drivers. - The series "mm/damon: introduce DAMOS filter type for active pages" from Nhat Pham permits users to filter for active/inactive pages, separately for file and anon pages. - The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia separates the proactive reclaim statistics from the direct reclaim statistics. - The series "mm/vmscan: don't try to reclaim hwpoison folio" from Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim code. * tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits) mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex() x86/mm: restore early initialization of high_memory for 32-bits mm/vmscan: don't try to reclaim hwpoison folio mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper cgroup: docs: add pswpin and pswpout items in cgroup v2 doc mm: vmscan: split proactive reclaim statistics from direct reclaim statistics selftests/mm: speed up split_huge_page_test selftests/mm: uffd-unit-tests support for hugepages > 2M docs/mm/damon/design: document active DAMOS filter type mm/damon: implement a new DAMOS filter type for active pages fs/dax: don't disassociate zero page entries MM documentation: add "Unaccepted" meminfo entry selftests/mm: add commentary about 9pfs bugs fork: use __vmalloc_node() for stack allocation docs/mm: Physical Memory: Populate the "Zones" section xen: balloon: update the NR_BALLOON_PAGES state hv_balloon: update the NR_BALLOON_PAGES state balloon_compaction: update the NR_BALLOON_PAGES state meminfo: add a per node counter for balloon drivers mm: remove references to folio in __memcg_kmem_uncharge_page() ...