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2025-11-17Documentation: admin-guide: blockdev: update zloop parametersDamien Le Moal
In Documentation/admin-guide/blockdev/zoned_loop.rst, add the description of the zone_append and ordered_zone_append configuration arguments of zloop "add" command (device creation). Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-16mm/swap: do not choose swap device according to numa nodeBaoquan He
Patch series "mm/swapfile.c: select swap devices of default priority round robin", v5. Currently, on system with multiple swap devices, swap allocation will select one swap device according to priority. The swap device with the highest priority will be chosen to allocate firstly. People can specify a priority from 0 to 32767 when swapon a swap device, or the system will set it from -2 then downwards by default. Meanwhile, on NUMA system, the swap device with node_id will be considered first on that NUMA node of the node_id. In the current code, an array of plist, swap_avail_heads[nid], is used to organize swap devices on each NUMA node. For each NUMA node, there is a plist organizing all swap devices. The 'prio' value in the plist is the negated value of the device's priority due to plist being sorted from low to high. The swap device owning one node_id will be promoted to the front position on that NUMA node, then other swap devices are put in order of their default priority. E.g I got a system with 8 NUMA nodes, and I setup 4 zram partition as swap devices. Current behaviour: their priorities will be(note that -1 is skipped): NAME TYPE SIZE USED PRIO /dev/zram0 partition 16G 0B -2 /dev/zram1 partition 16G 0B -3 /dev/zram2 partition 16G 0B -4 /dev/zram3 partition 16G 0B -5 And their positions in the 8 swap_avail_lists[nid] will be: swap_avail_lists[0]: /* node 0's available swap device list */ zram0 -> zram1 -> zram2 -> zram3 prio:1 prio:3 prio:4 prio:5 swap_avali_lists[1]: /* node 1's available swap device list */ zram1 -> zram0 -> zram2 -> zram3 prio:1 prio:2 prio:4 prio:5 swap_avail_lists[2]: /* node 2's available swap device list */ zram2 -> zram0 -> zram1 -> zram3 prio:1 prio:2 prio:3 prio:5 swap_avail_lists[3]: /* node 3's available swap device list */ zram3 -> zram0 -> zram1 -> zram2 prio:1 prio:2 prio:3 prio:4 swap_avail_lists[4-7]: /* node 4,5,6,7's available swap device list */ zram0 -> zram1 -> zram2 -> zram3 prio:2 prio:3 prio:4 prio:5 The adjustment for swap device with node_id intended to decrease the pressure of lock contention for one swap device by taking different swap device on different node. The adjustment was introduced in commit a2468cc9bfdf ("swap: choose swap device according to numa node"). However, the adjustment is a little coarse-grained. On the node, the swap device sharing the node's id will always be selected firstly by node's CPUs until exhausted, then next one. And on other nodes where no swap device shares its node id, swap device with priority '-2' will be selected firstly until exhausted, then next with priority '-3'. This is the swapon output during the process high pressure vm-scability test is being taken. It's clearly showing zram0 is heavily exploited until exhausted. =================================== [root@hp-dl385g10-03 ~]# swapon NAME TYPE SIZE USED PRIO /dev/zram0 partition 16G 15.7G -2 /dev/zram1 partition 16G 3.4G -3 /dev/zram2 partition 16G 3.4G -4 /dev/zram3 partition 16G 2.6G -5 The node based strategy on selecting swap device is much better then the old way one by one selecting swap device. However it is still unreasonable because swap devices are assumed to have similar accessing speed if no priority is specified when swapon. It's unfair and doesn't make sense just because one swap device is swapped on firstly, its priority will be higher than the one swapped on later. So in this patchset, change is made to select the swap device round robin if default priority. In code, the plist array swap_avail_heads[nid] is replaced with a plist swap_avail_head which reverts commit a2468cc9bfdf. Meanwhile, on top of the revert, further change is taken to make any device w/o specified priority get the same default priority '-1'. Surely, swap device with specified priority are always put foremost, this is not impacted. If you care about their different accessing speed, then use 'swapon -p xx' to deploy priority for your swap devices. New behaviour: swap_avail_list: /* one global available swap device list */ zram0 -> zram1 -> zram2 -> zram3 prio:1 prio:1 prio:1 prio:1 This is the swapon output during the process high pressure vm-scability being taken, all is selected round robin: ======================================= [root@hp-dl385g10-03 linux]# swapon NAME TYPE SIZE USED PRIO /dev/zram0 partition 16G 12.6G -1 /dev/zram1 partition 16G 12.6G -1 /dev/zram2 partition 16G 12.6G -1 /dev/zram3 partition 16G 12.6G -1 With the change, we can see about 18% efficiency promotion as below: vm-scability test: ================== Test with: usemem --init-time -O -y -x -n 31 2G (4G memcg, zram as swap) Before: After: System time: 637.92 s 526.74 s (lower is better) Sum Throughput: 3546.56 MB/s 4207.56 MB/s (higher is better) Single process Throughput: 114.40 MB/s 135.72 MB/s (higher is better) free latency: 10138455.99 us 6810119.01 us (low is better) This patch (of 2): This reverts commit a2468cc9bfdf ("swap: choose swap device according to numa node"). After this patch, the behaviour will change back to pre-commit a2468cc9bfdf. Means the priority will be set from -1 then downwards by default, and when swapping, it will exhault swap device one by one according to priority from high to low. This is preparation work for later change. [root@hp-dl385g10-03 ~]# swapon NAME TYPE SIZE USED PRIO /dev/zram0 partition 16G 16G -1 /dev/zram1 partition 16G 966.2M -2 /dev/zram2 partition 16G 0B -3 /dev/zram3 partition 16G 0B -4 Link: https://lkml.kernel.org/r/20251028034308.929550-1-bhe@redhat.com Link: https://lkml.kernel.org/r/20251028034308.929550-2-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Suggested-by: Chris Li <chrisl@kernel.org> Acked-by: Chris Li <chrisl@kernel.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Kairui Song <kasong@tencent.com> Cc: Barry Song <baohua@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/usage: document obsolete_target fileSeongJae Park
Document the newly added obsolete_target DAMON sysfs file. Link: https://lkml.kernel.org/r/20251023012535.69625-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Reviewed-by: Bijan Tabatabai <bijan311@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16mm: shmem/tmpfs hugepage defaults config choiceDmitry Ilvokhin
Allow to override defaults for shemem and tmpfs at config time. This is consistent with how transparent hugepages can be configured. Same results can be achieved with the existing 'transparent_hugepage_shmem' and 'transparent_hugepage_tmpfs' settings in the kernel command line, but it is more convenient to define basic settings at config time instead of changing kernel command line later. Defaults for shmem and tmpfs were not changed. They are remained the same as before: 'never' for both cases. Options 'deny' and 'force' are omitted intentionally since these are special values and supposed to be used for emergencies or testing and are not expected to be permanent ones. Primary motivation for adding config option is to enable policy enforcement at build time. In large-scale production environments (Meta's for example), the kernel configuration is often maintained centrally close to the kernel code itself and owned by the kernel engineers, while boot parameters are managed independently (e.g. by provisioning systems). In such setups, the kernel build defines the supported and expected behavior in a single place, but there is no reliable or uniform control over the kernel command line options. A build-time default allows kernel integrators to enforce a predictable hugepage policy for shmem/tmpfs on a base layer, ensuring reproducible behavior and avoiding configuration drift caused by possible boot-time differences. In short, primary benefit is mostly operational: it provides a way to codify preferred policy in the kernel configuration, which is versioned, reviewed, and tested as part of the kernel build process, rather than depending on potentially variable boot parameters. [d@ilvokhin.com: v2] Link: https://lkml.kernel.org/r/aQECPpjd-fU_TC79@shell.ilvokhin.com Link: https://lkml.kernel.org/r/aPpv8sAa2sYgNu3L@shell.ilvokhin.com Signed-off-by: Dmitry Ilvokhin <d@ilvokhin.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: Kiryl Shutsemau <kas@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/stat: document negative idle timeSeongJae Park
Commit a983a26d5298 ("mm/damon/stat: expose negative idle time") introduced the negative idle time feature for DAMON_STAT. But it is not documented. Document it on the usage document. Link: https://lkml.kernel.org/r/20251026182216.118200-9-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/stat: document aggr_interval_us parameterSeongJae Park
Commit cc7ceb1d14b0 ("mm/damon/stat: expose the current tuned aggregation interval"), has introduced 'aggr_interval_us' parameter for DAMON_STAT. But the new parameter is not yet documented. Document it on the usage document for the module. Link: https://lkml.kernel.org/r/20251026182216.118200-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/lru_sort: document addr_unit parameterSeongJae Park
Commit 2e0fe9245d6b ("mm/damon/lru_sort: support addr_unit for DAMON_LRU_SORT") introduced the 'addr_unit' parameter for DAMON_LRU_SORT. But the usage document is not updated for that. Update the document. Link: https://lkml.kernel.org/r/20251026182216.118200-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/reclaim: document addr_unit parameterSeongJae Park
Commit 7db551fcfb2a ("mm/damon/reclaim: support addr_unit for DAMON_RECLAIM") introduced the 'addr_unit' parameter for DAMON_RECLAIM. But the usage document is not updated for that. Update the document. Link: https://lkml.kernel.org/r/20251026182216.118200-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/usage: document empty target regions commit behaviorSeongJae Park
Committing a monitoring target with empty target regions is for keeping the current monitoring results. This behavior was introduced by commit 973233600676 ("mm/damon/sysfs: update monitoring target regions for online input commit"). The behavior is not documented, though. Update the usage document for clarifying this behavior. Link: https://lkml.kernel.org/r/20251026182216.118200-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/stat: fix a typo: s/sampling events/sampling interval/SeongJae Park
It is a contextual typo. Fix it. Link: https://lkml.kernel.org/r/20251026182216.118200-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/damon/usage: document DAMOS quota goal path fileSeongJae Park
A new DAMON sysfs interface file, namely 'path' has been added under DAMOS quota goal directory, for specifying the cgroup for DAMOS_QUOTA_NODE_MEMCG_{USED,FREE}_BP metrics. Document it on the usage document. Link: https://lkml.kernel.org/r/20251017212706.183502-10-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16memcg: net: track network throttling due to memcg memory pressureShakeel Butt
The kernel can throttle network sockets if the memory cgroup associated with the corresponding socket is under memory pressure. The throttling actions include clamping the transmit window, failing to expand receive or send buffers, aggressively prune out-of-order receive queue, FIN deferred to a retransmitted packet and more. Let's add memcg metric to track such throttling actions. At the moment memcg memory pressure is defined through vmpressure and in future it may be defined using PSI or we may add more flexible way for the users to define memory pressure, maybe through ebpf. However the potential throttling actions will remain the same, so this newly introduced metric will continue to track throttling actions irrespective of how memcg memory pressure is defined. Link: https://lkml.kernel.org/r/20251016161035.86161-1-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Daniel Sedlak <daniel.sedlak@cdn77.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Neal Cardwell <ncardwell@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Simon Horman <horms@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-16Docs/admin-guide/mm/zswap: s/red-black tree/xarray/SeongJae Park
The change from commit 796c2c23e14e ("zswap: replace RB tree with xarray") is not reflected on the document. Update the document. Link: https://lkml.kernel.org/r/20251003203851.43128-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: Yosry Ahmed <yosry.ahmed@linux.dev> Acked-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-15Documentation: admin-guide: media: add rockchip camera interfaceMichael Riesch
Add a document that describes the different variants of the Rockchip Camera Interface (CIF), their hardware layout, as well as their representation in the media controller centric rkcif device driver, which is located under drivers/media/platform/rockchip/rkcif. Reviewed-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> Signed-off-by: Michael Riesch <michael.riesch@collabora.com> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2025-11-14docs: cgroup: No special handling of unpopulated memcgsMichal Koutný
The current kernel doesn't handle unpopulated cgroups any special regarding reclaim protection. Furthermore, this wasn't a case even when this was introduced in bf8d5d52ffe89 ("memcg: introduce memory.min") Drop the incorrect documentation. (Implementation taking into account the inner-node constraint may be added later.) Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-14docs: cgroup: Note about sibling relative reclaim protectionMichal Koutný
Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-14docs: cgroup: Explain reclaim protection targetMichal Koutný
The protection target is necessary to understand how effective reclaim protection applies in the hierarchy. Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-14Documentation: thermal: Document thermal throttling on Intel platformsSrinivas Pandruvada
Add documentation for Intel thermal throttling reporting events. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> [ rjw: Subject adjustment, file name change, minor edits ] Link: https://patch.msgid.link/20251113212104.221632-1-srinivas.pandruvada@linux.intel.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-11-14Documentation: media: mali-c55: Document the mali-c55 parameter settingDaniel Scally
Document the mali-c55 parameter setting by expanding the relevant pages in both admin-guide/ and userspace-api/. Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Nayden Kanchev <nayden.kanchev@arm.com> Co-developed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2025-11-14Documentation: media: mali-c55: Add Statistics documentationDaniel Scally
Add documentation explaining the ability to capture statistics from the mali-c55 driver's new V4L2 device, as well as the various tap points from which those statistics can be drawn in the ISP's processing flow. Additionally add a page detailing the new V4L2 meta format for the mali-c55 statistics. Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Nayden Kanchev <nayden.kanchev@arm.com> Co-developed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2025-11-14media: Documentation: Add Mali-C55 ISP DocumentationDaniel Scally
Add a documentation page for the mali-c55 driver, which gives a brief overview of the hardware and explains how to use the driver's capture devices and the crop/scaler functions. Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Nayden Kanchev <nayden.kanchev@arm.com> Co-developed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com> Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2025-11-13bcache: remove discard sysfs interface documentColy Li
This patch removes documents of bcache discard sysfs interface, it drops discard related sections from, - Documentation/ABI/testing/sysfs-block-bcache - Documentation/admin-guide/bcache.rst Signed-off-by: Coly Li <colyli@fnnas.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-12dynamic_debug: add support for print stackYe Bin
In practical problem diagnosis, especially during the boot phase, it is often desirable to know the call sequence. However, currently, apart from adding print statements and recompiling the kernel, there seems to be no good alternative. If dynamic_debug supported printing the call stack, it would be very helpful for diagnosing issues. This patch add support '+d' for dump stack. Link: https://lkml.kernel.org/r/20251025080003.312536-1-yebin@huaweicloud.com Signed-off-by: Ye Bin <yebin10@huawei.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Jim Cromie <jim.cromie@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-12hung_task: panic when there are more than N hung tasks at the same timeLi RongQing
The hung_task_panic sysctl is currently a blunt instrument: it's all or nothing. Panicking on a single hung task can be an overreaction to a transient glitch. A more reliable indicator of a systemic problem is when multiple tasks hang simultaneously. Extend hung_task_panic to accept an integer threshold, allowing the kernel to panic only when N hung tasks are detected in a single scan. This provides finer control to distinguish between isolated incidents and system-wide failures. The accepted values are: - 0: Don't panic (unchanged) - 1: Panic on the first hung task (unchanged) - N > 1: Panic after N hung tasks are detected in a single scan The original behavior is preserved for values 0 and 1, maintaining full backward compatibility. [lance.yang@linux.dev: new changelog] Link: https://lkml.kernel.org/r/20251015063615.2632-1-lirongqing@baidu.com Signed-off-by: Li RongQing <lirongqing@baidu.com> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Lance Yang <lance.yang@linux.dev> Tested-by: Lance Yang <lance.yang@linux.dev> Acked-by: Andrew Jeffery <andrew@codeconstruct.com.au> [aspeed_g5_defconfig] Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Hildenbrand <david@redhat.com> Cc: Florian Wesphal <fw@strlen.de> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Jason A. Donenfeld <jason@zx2c4.com> Cc: Joel Granados <joel.granados@kernel.org> Cc: Joel Stanley <joel@jms.id.au> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <kees@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Phil Auld <pauld@redhat.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Horman <horms@kernel.org> Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-11powerpc/kdump: Add support for crashkernel CMA reservationSourabh Jain
Commit 35c18f2933c5 ("Add a new optional ",cma" suffix to the crashkernel= command line option") and commit ab475510e042 ("kdump: implement reserve_crashkernel_cma") added CMA support for kdump crashkernel reservation. Extend crashkernel CMA reservation support to powerpc. The following changes are made to enable CMA reservation on powerpc: - Parse and obtain the CMA reservation size along with other crashkernel parameters - Call reserve_crashkernel_cma() to allocate the CMA region for kdump - Include the CMA-reserved ranges in the usable memory ranges for the kdump kernel to use. - Exclude the CMA-reserved ranges from the crash kernel memory to prevent them from being exported through /proc/vmcore. With the introduction of the CMA crashkernel regions, crash_exclude_mem_range() needs to be called multiple times to exclude both crashk_res and crashk_cma_ranges from the crash memory ranges. To avoid repetitive logic for validating mem_ranges size and handling reallocation when required, this functionality is moved to a new wrapper function crash_exclude_mem_range_guarded(). To ensure proper CMA reservation, reserve_crashkernel_cma() is called after pageblock_order is initialized. Update kernel-parameters.txt to document CMA support for crashkernel on powerpc architecture. Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20251107080334.708028-1-sourabhjain@linux.ibm.com
2025-11-11md: allow configuring logical block sizeLi Nan
Previously, raid array used the maximum logical block size (LBS) of all member disks. Adding a larger LBS disk at runtime could unexpectedly increase RAID's LBS, risking corruption of existing partitions. This can be reproduced by: ``` # LBS of sd[de] is 512 bytes, sdf is 4096 bytes. mdadm -CRq /dev/md0 -l1 -n3 /dev/sd[de] missing --assume-clean # LBS is 512 cat /sys/block/md0/queue/logical_block_size # create partition md0p1 parted -s /dev/md0 mklabel gpt mkpart primary 1MiB 100% lsblk | grep md0p1 # LBS becomes 4096 after adding sdf mdadm --add -q /dev/md0 /dev/sdf cat /sys/block/md0/queue/logical_block_size # partition lost partprobe /dev/md0 lsblk | grep md0p1 ``` Simply restricting larger-LBS disks is inflexible. In some scenarios, only disks with 512 bytes LBS are available currently, but later, disks with 4KB LBS may be added to the array. Making LBS configurable is the best way to solve this scenario. After this patch, the raid will: - store LBS in disk metadata - add a read-write sysfs 'mdX/logical_block_size' Future mdadm should support setting LBS via metadata field during RAID creation and the new sysfs. Though the kernel allows runtime LBS changes, users should avoid modifying it after creating partitions or filesystems to prevent compatibility issues. Only 1.x metadata supports configurable LBS. 0.90 metadata inits all fields to default values at auto-detect. Supporting 0.90 would require more extensive changes and no such use case has been observed. Note that many RAID paths rely on PAGE_SIZE alignment, including for metadata I/O. A larger LBS than PAGE_SIZE will result in metadata read/write failures. So this config should be prevented. Link: https://lore.kernel.org/linux-raid/20251103125757.1405796-6-linan666@huaweicloud.com Signed-off-by: Li Nan <linan122@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Yu Kuai <yukuai@fnnas.com>
2025-11-10docs: Fix missing word in spectre.rstpierwill
Corrects a missing word in the hardware vulnerability docs. Signed-off-by: Will Pierce <pierwill@protonmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <Ru-d3ltJIyY4Oc6tzHwpSiDeFwSLHEzd7Utcr6iobgIy1B8wLRI4f6JiCb0a9n-0-r19d0dyLL3yS8KWVcyHfpkyDErWXYTkI3AJfUPTNCc=@protonmail.com>
2025-11-10Documentation: laptops: Add documentation for uniwill laptopsArmin Wolf
Add documentation for admins regarding Uniwill laptops. This should help them to setup the uniwill-laptop driver, which sadly cannot be loaded automatically. Reported-by: cyear <chumuzero@gmail.com> Closes: https://github.com/lm-sensors/lm-sensors/issues/508 Closes: https://github.com/Wer-Wolf/uniwill-laptop/issues/3 Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://patch.msgid.link/20251102172942.17879-3-W_Armin@gmx.de Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-11-07net: increase skb_defer_max default to 128Eric Dumazet
skb_defer_max value is very conservative, and can be increased to avoid too many calls to kick_defer_list_purge(). Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://patch.msgid.link/20251106202935.1776179-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-06mfd: wl1273-core: Remove the headerDr. David Alan Gilbert
The wl1273 FM radio is on Arnd's unused driver list: https://lore.kernel.org/lkml/a15bb180-401d-49ad-a212-0c81d613fbc8@app.fastmail.com/ Other patches have removed the core, the ASoC code and the Radio code. With all those in, remove the header. Also, tidy the ref in the docs. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Lee Jones <lee@kernel.org>
2025-11-06EDAC: Remove the legacy EDAC sysfs interfaceAvadhut Naik
Commit 199747106934 ("edac: add a new per-dimm API and make the old per-virtual-rank API obsolete") introduced a new per-DIMM sysfs interface for EDAC making the old per-virtual-rank sysfs interface obsolete. Since this new sysfs interface was introduced more than a decade ago, remove the obsolete legacy interface. Signed-off-by: Avadhut Naik <avadhut.naik@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20251106015727.1987246-1-avadhut.naik@amd.com
2025-11-04rseq: Provide static branch for runtime debuggingThomas Gleixner
Config based debug is rarely turned on and is not available easily when things go wrong. Provide a static branch to allow permanent integration of debug mechanisms along with the usual toggles in Kconfig, command line and debugfs. Requested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/20251027084307.089270547@linutronix.de
2025-11-03Documentation: intel-pstate: Use :ref: directive for internal linkingBagas Sanjaya
intel_pstate docs uses standard reST construct (`Section title`_) for cross-referencing sections (internal linking), rather than for external links. Incorrect cross-references are not caught when these are written in that syntax, however (fortunately docutils 0.22 raise duplicate target warnings that get fixed in cb908f8b0acc7e ("Documentation: intel_pstate: fix duplicate hyperlink target errors")). Convert the cross-references to use :ref: directive, which doesn't exhibit this problem. Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> [ rjw: Changelog tweak ] Link: https://patch.msgid.link/20251101055614.32270-1-bagasdotme@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-11-03thunderbolt: Update NVM firmware upgrade documentationAlan Borzeszkowski
Update guide about firmware upgrade of Thunderbolt devices, replacing outdated recommendations with the use of modern "fwupd" tool. Signed-off-by: Alan Borzeszkowski <alan.borzeszkowski@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2025-10-30PM: hibernate: make compression threads configurableXueqin Luo
The number of compression/decompression threads has a direct impact on hibernate image generation and resume latency. Using more threads can reduce overall resume time, but on systems with fewer CPU cores it may also introduce contention and reduce efficiency. Performance was evaluated on an 8-core ARM system, averaged over 10 runs: Threads Hibernate(s) Resume(s) -------------------------------- 3 12.14 18.86 4 12.28 17.48 5 11.09 16.77 6 11.08 16.44 With 5–6 threads, resume latency improves by approximately 12% compared to the default 3-thread configuration, with negligible impact on hibernate time. Introduce a new kernel parameter `hibernate_compression_threads=` that allows users and integrators to tune the number of compression/decompression threads at boot. This provides a way to balance performance and CPU utilization across a wide range of hardware without recompiling the kernel. Signed-off-by: Xueqin Luo <luoxueqin@kylinos.cn> Link: https://patch.msgid.link/f24b3ca6416e230a515a154ed4c121d72a7e05a6.1761046167.git.luoxueqin@kylinos.cn Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-10-29Documentation: fix reference to PR_SPEC_L1D_FLUSHBrendan Jackman
PR_SET_L1D_FLUSH does not exist. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20251015-l1d-flush-doc-v1-2-f8cefea3f2f2@google.com>
2025-10-29Documentation: intel_pstate: fix duplicate hyperlink target errorsSwaraj Gaikwad
Fix reST warnings in Documentation/admin-guide/pm/intel_pstate.rst caused by missing explicit hyperlink labels for section titles. Before this change, the following errors were printed during `make htmldocs`: Documentation/admin-guide/pm/intel_pstate.rst:401: ERROR: Indirect hyperlink target (id="id6") refers to target "passive mode", which is a duplicate, and cannot be used as a unique reference. Documentation/admin-guide/pm/intel_pstate.rst:517: ERROR: Indirect hyperlink target (id="id9") refers to target "active mode", which is a duplicate, and cannot be used as a unique reference. Documentation/admin-guide/pm/intel_pstate.rst:611: ERROR: Indirect hyperlink target (id="id15") refers to target "global attributes", which is a duplicate, and cannot be used as a unique reference. ERROR: Duplicate target name, cannot be used as a unique reference: "passive mode", "active mode", "global attributes". These errors occurred because the sections "Active Mode", "Active Mode With HWP", "Passive Mode", and "Global Attributes" did not define explicit hyperlink labels. As a result, Sphinx auto-generated duplicate anchors when the same titles appeared multiple times within the document. Because of this, the generated HTML documentation contained broken references such as: `active mode <Active Mode_>`_ `passive mode <Passive Mode_>`_ `global attributes <Global Attributes_>`_ This patch adds explicit hyperlink labels for the affected sections, ensuring all references are unique and correctly resolved. After applying this patch, `make htmldocs` completes without any warnings, and all hyperlinks in intel_pstate.html render properly. Signed-off-by: Swaraj Gaikwad <swarajgaikwad1925@gmail.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> [ rjw: Subject adjustment ] Link: https://patch.msgid.link/20251029134737.42229-1-swarajgaikwad1925@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-10-17docs: admin-guide: Fix a typo in kernel-parameters.txtYohei Kojima
Fix a typo in the stacktrace parameter description in kernel-parameters.txt Signed-off-by: Yohei Kojima <Yohei.Kojima@sony.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <edda15e3fcae13265278d3c3bd93ab077345d78f.1760498951.git.Yohei.Kojima@sony.com>
2025-10-16net: Introduce net.core.bypass_prot_mem sysctl.Kuniyuki Iwashima
If a socket has sk->sk_bypass_prot_mem flagged, the socket opts out of the global protocol memory accounting. Let's control the flag by a new sysctl knob. The flag is written once during socket(2) and is inherited to child sockets. Tested with a script that creates local socket pairs and send()s a bunch of data without recv()ing. Setup: # mkdir /sys/fs/cgroup/test # echo $$ >> /sys/fs/cgroup/test/cgroup.procs # sysctl -q net.ipv4.tcp_mem="1000 1000 1000" # ulimit -n 524288 Without net.core.bypass_prot_mem, charged to tcp_mem & memcg # python3 pressure.py & # cat /sys/fs/cgroup/test/memory.stat | grep sock sock 22642688 <-------------------------------------- charged to memcg # cat /proc/net/sockstat| grep TCP TCP: inuse 2006 orphan 0 tw 0 alloc 2008 mem 5376 <-- charged to tcp_mem # ss -tn | head -n 5 State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:53188 ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:49972 ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:53868 ESTAB 2000 0 127.0.0.1:34479 127.0.0.1:53554 # nstat | grep Pressure || echo no pressure TcpExtTCPMemoryPressures 1 0.0 With net.core.bypass_prot_mem=1, charged to memcg only: # sysctl -q net.core.bypass_prot_mem=1 # python3 pressure.py & # cat /sys/fs/cgroup/test/memory.stat | grep sock sock 2757468160 <------------------------------------ charged to memcg # cat /proc/net/sockstat | grep TCP TCP: inuse 2006 orphan 0 tw 0 alloc 2008 mem 0 <- NOT charged to tcp_mem # ss -tn | head -n 5 State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 111000 0 127.0.0.1:36019 127.0.0.1:49026 ESTAB 110000 0 127.0.0.1:36019 127.0.0.1:45630 ESTAB 110000 0 127.0.0.1:36019 127.0.0.1:44870 ESTAB 111000 0 127.0.0.1:36019 127.0.0.1:45274 # nstat | grep Pressure || echo no pressure no pressure Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Link: https://patch.msgid.link/20251014235604.3057003-4-kuniyu@google.com
2025-10-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.18-rc2). No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-15net: add /proc/sys/net/core/txq_reselection_ms controlEric Dumazet
Add a new sysctl to control how often a queue reselection can happen even if a flow has a persistent queue of skbs in a Qdisc or NIC queue. A value of zero means the feature is disabled. Default is 1000 (1 second). This sysctl is used in the following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20251013152234.842065-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-10-14Documentation: admin-guide: Correct spelling of "userspace"Akiyoshi Kurita
The term "userspace" should be a single word. Fix the typo "userpace" accordingly. Signed-off-by: Akiyoshi Kurita <weibu@redadmin.org> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20250926190019.41788-1-weibu@redadmin.org>
2025-10-14Documentation/x86: explain LINUX_EFI_INITRD_MEDIA_GUIDHugo Osvaldo Barrera
Since the Handover Protocol was deprecated, the recommended approach is to provide an initrd using a UEFI boot service with the LINUX_EFI_INITRD_MEDIA_GUID device path. Documentation for the new approach has been no more than an admonition with a link to an existing implementation. Provide a short explanation of this functionality, to ease future implementations without having to reverse engineer existing ones. [Bagas: Don't use :ref: link to EFI stub documentation and refer to OVMF/edk2 implementation] Signed-off-by: Hugo Osvaldo Barrera <hugo@whynothugo.nl> Link: https://lore.kernel.org/r/20250428131206.8656-2-hugo@whynothugo.nl Co-developed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20251013085718.27085-1-bagasdotme@gmail.com>
2025-10-14media: doc/dt-bindings: remove support of stih407-c8sectpfeRaphael Gallais-Pou
Remove files documentation from stih407-c8sectpfe driver. Signed-off-by: Raphael Gallais-Pou <rgallaispou@gmail.com> Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> Acked-by: Rob Herring (Arm) <robh@kernel.org> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org> [hverkuil: slight change of the Subject, mention doc changes as well]
2025-10-11Merge tag 'x86_core_for_v6.18_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more x86 updates from Borislav Petkov: - Remove a bunch of asm implementing condition flags testing in KVM's emulator in favor of int3_emulate_jcc() which is written in C - Replace KVM fastops with C-based stubs which avoids problems with the fastop infra related to latter not adhering to the C ABI due to their special calling convention and, more importantly, bypassing compiler control-flow integrity checking because they're written in asm - Remove wrongly used static branches and other ugliness accumulated over time in hyperv's hypercall implementation with a proper static function call to the correct hypervisor call variant - Add some fixes and modifications to allow running FRED-enabled kernels in KVM even on non-FRED hardware - Add kCFI improvements like validating indirect calls and prepare for enabling kCFI with GCC. Add cmdline params documentation and other code cleanups - Use the single-byte 0xd6 insn as the official #UD single-byte undefined opcode instruction as agreed upon by both x86 vendors - Other smaller cleanups and touchups all over the place * tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86,retpoline: Optimize patch_retpoline() x86,ibt: Use UDB instead of 0xEA x86/cfi: Remove __noinitretpoline and __noretpoline x86/cfi: Add "debug" option to "cfi=" bootparam x86/cfi: Standardize on common "CFI:" prefix for CFI reports x86/cfi: Document the "cfi=" bootparam options x86/traps: Clarify KCFI instruction layout compiler_types.h: Move __nocfi out of compiler-specific header objtool: Validate kCFI calls x86/fred: KVM: VMX: Always use FRED for IRQs when CONFIG_X86_FRED=y x86/fred: Play nice with invoking asm_fred_entry_from_kvm() on non-FRED hardware x86/fred: Install system vector handlers even if FRED isn't fully enabled x86/hyperv: Use direct call to hypercall-page x86/hyperv: Clean up hv_do_hypercall() KVM: x86: Remove fastops KVM: x86: Convert em_salc() to C KVM: x86: Introduce EM_ASM_3WCL KVM: x86: Introduce EM_ASM_1SRC2 KVM: x86: Introduce EM_ASM_2CL KVM: x86: Introduce EM_ASM_2W ...
2025-10-07Merge tag 'pm-6.18-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "These are cpufreq fixes and cleanups on top of the material merged previously, a power management core code fix and updates of the runtime PM framework including unit tests, documentation updates and introduction of auto-cleanup macros for runtime PM "resume and get" and "get without resuming" operations. Specifics: - Make cpufreq drivers setting the default CPU transition latency to CPUFREQ_ETERNAL specify a proper default transition latency value instead which addresses a regression introduced during the 6.6 cycle that broke CPUFREQ_ETERNAL handling (Rafael Wysocki) - Make the cpufreq CPPC driver use a proper transition delay value when CPUFREQ_ETERNAL is returned by cppc_get_transition_latency() to indicate an error condition (Rafael Wysocki) - Make cppc_get_transition_latency() return a negative error code to indicate error conditions instead of using CPUFREQ_ETERNAL for this purpose and drop CPUFREQ_ETERNAL that has no other users (Rafael Wysocki, Gopi Krishna Menon) - Fix device leak in the mediatek cpufreq driver (Johan Hovold) - Set target frequency on all CPUs sharing a policy during frequency updates in the tegra186 cpufreq driver and make it initialize all cores to max frequencies (Aaron Kling) - Rust cpufreq helper cleanup (Thorsten Blum) - Make pm_runtime_put*() family of functions return 1 when the given device is already suspended which is consistent with the documentation (Brian Norris) - Add basic kunit tests for runtime PM API contracts and update return values in kerneldoc comments for the runtime PM API (Brian Norris, Dan Carpenter) - Add auto-cleanup macros for runtime PM "resume and get" and "get without resume" operations, use one of them in the PCI core and drop the existing "free" macro introduced for similar purpose, but somewhat cumbersome to use (Rafael Wysocki) - Make the core power management code avoid waiting on device links marked as SYNC_STATE_ONLY which is consistent with the handling of those device links elsewhere (Pin-yen Lin)" * tag 'pm-6.18-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: docs/zh_CN: Fix malformed table docs/zh_TW: Fix malformed table PM: runtime: Fix error checking for kunit_device_register() PM: runtime: Introduce one more usage counter guard cpufreq: Drop unused symbol CPUFREQ_ETERNAL ACPI: CPPC: Do not use CPUFREQ_ETERNAL as an error value cpufreq: CPPC: Avoid using CPUFREQ_ETERNAL as transition delay cpufreq: Make drivers using CPUFREQ_ETERNAL specify transition latency PM: runtime: Drop DEFINE_FREE() for pm_runtime_put() PCI/sysfs: Use runtime PM guard macro for auto-cleanup PM: runtime: Add auto-cleanup macros for "resume and get" operations cpufreq: tegra186: Initialize all cores to max frequencies cpufreq: tegra186: Set target frequency for all cpus in policy rust: cpufreq: streamline find_supply_names cpufreq: mediatek: fix device leak on probe failure PM: sleep: Do not wait on SYNC_STATE_ONLY device links PM: runtime: Update kerneldoc return codes PM: runtime: Make put{,_sync}() return 1 when already suspended PM: runtime: Add basic kunit tests for API contracts
2025-10-07Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: - Preserve old 'tt_core' UAPI for Hisilicon L3C PMU driver - Ensure linear alias of kprobes instruction page is not writable - Fix kernel stack unwinding from BPF - Fix build warnings from the Fujitsu uncore PMU documentation - Fix hang with deferred 'struct page' initialisation and MTE - Consolidate KPTI page-table re-writing code * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: mte: Do not flag the zero page as PG_mte_tagged docs: perf: Fujitsu: Fix htmldocs build warnings and errors arm64: mm: Move KPTI helpers to mmu.c tracing: Fix the bug where bpf_get_stackid returns -EFAULT on the ARM64 arm64: kprobes: call set_memory_rox() for kprobe page drivers/perf: hisi: Add tt_core_deprecated for compatibility
2025-10-07Merge branch 'pm-cpufreq'Rafael J. Wysocki
Merge cpufreq fixes and cleanups, mostly on top of those fixes, for 6.18-rc1: - Make cpufreq drivers setting the default CPU transition latency to CPUFREQ_ETERNAL specify a proper default transition latency value instead which addresses a regression introduced during the 6.6 cycle that broke CPUFREQ_ETERNAL handling (Rafael Wysocki) - Make the cpufreq CPPC driver use a proper transition delay value when CPUFREQ_ETERNAL is returned by cppc_get_transition_latency() to indicate an error condition (Rafael Wysocki) - Make cppc_get_transition_latency() return a negative error code to indicate error conditions instead of using CPUFREQ_ETERNAL for this purpose and drop CPUFREQ_ETERNAL that has no other users (Rafael Wysocki, Gopi Krishna Menon) - Fix device leak in the mediatek cpufreq driver (Johan Hovold) - Set target frequency on all CPUs sharing a policy during frequency updates in the tegra186 cpufreq driver and make it initialize all cores to max frequencies (Aaron Kling) - Rust cpufreq helper cleanup (Thorsten Blum) * pm-cpufreq: docs/zh_CN: Fix malformed table docs/zh_TW: Fix malformed table cpufreq: Drop unused symbol CPUFREQ_ETERNAL ACPI: CPPC: Do not use CPUFREQ_ETERNAL as an error value cpufreq: CPPC: Avoid using CPUFREQ_ETERNAL as transition delay cpufreq: Make drivers using CPUFREQ_ETERNAL specify transition latency cpufreq: tegra186: Initialize all cores to max frequencies cpufreq: tegra186: Set target frequency for all cpus in policy rust: cpufreq: streamline find_supply_names cpufreq: mediatek: fix device leak on probe failure
2025-10-06Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull x86 kvm updates from Paolo Bonzini: "Generic: - Rework almost all of KVM's exports to expose symbols only to KVM's x86 vendor modules (kvm-{amd,intel}.ko and PPC's kvm-{pr,hv}.ko x86: - Rework almost all of KVM x86's exports to expose symbols only to KVM's vendor modules, i.e. to kvm-{amd,intel}.ko - Add support for virtualizing Control-flow Enforcement Technology (CET) on Intel (Shadow Stacks and Indirect Branch Tracking) and AMD (Shadow Stacks). It is worth noting that while SHSTK and IBT can be enabled separately in CPUID, it is not really possible to virtualize them separately. Therefore, Intel processors will really allow both SHSTK and IBT under the hood if either is made visible in the guest's CPUID. The alternative would be to intercept XSAVES/XRSTORS, which is not feasible for performance reasons - Fix a variety of fuzzing WARNs all caused by checking L1 intercepts when completing userspace I/O. KVM has already committed to allowing L2 to to perform I/O at that point - Emulate PERF_CNTR_GLOBAL_STATUS_SET for PerfMonV2 guests, as the MSR is supposed to exist for v2 PMUs - Allow Centaur CPU leaves (base 0xC000_0000) for Zhaoxin CPUs - Add support for the immediate forms of RDMSR and WRMSRNS, sans full emulator support (KVM should never need to emulate the MSRs outside of forced emulation and other contrived testing scenarios) - Clean up the MSR APIs in preparation for CET and FRED virtualization, as well as mediated vPMU support - Clean up a pile of PMU code in anticipation of adding support for mediated vPMUs - Reject in-kernel IOAPIC/PIT for TDX VMs, as KVM can't obtain EOI vmexits needed to faithfully emulate an I/O APIC for such guests - Many cleanups and minor fixes - Recover possible NX huge pages within the TDP MMU under read lock to reduce guest jitter when restoring NX huge pages - Return -EAGAIN during prefault if userspace concurrently deletes/moves the relevant memslot, to fix an issue where prefaulting could deadlock with the memslot update x86 (AMD): - Enable AVIC by default for Zen4+ if x2AVIC (and other prereqs) is supported - Require a minimum GHCB version of 2 when starting SEV-SNP guests via KVM_SEV_INIT2 so that invalid GHCB versions result in immediate errors instead of latent guest failures - Add support for SEV-SNP's CipherText Hiding, an opt-in feature that prevents unauthorized CPU accesses from reading the ciphertext of SNP guest private memory, e.g. to attempt an offline attack. This feature splits the shared SEV-ES/SEV-SNP ASID space into separate ranges for SEV-ES and SEV-SNP guests, therefore a new module parameter is needed to control the number of ASIDs that can be used for VMs with CipherText Hiding vs. how many can be used to run SEV-ES guests - Add support for Secure TSC for SEV-SNP guests, which prevents the untrusted host from tampering with the guest's TSC frequency, while still allowing the the VMM to configure the guest's TSC frequency prior to launch - Validate the XCR0 provided by the guest (via the GHCB) to avoid bugs resulting from bogus XCR0 values - Save an SEV guest's policy if and only if LAUNCH_START fully succeeds to avoid leaving behind stale state (thankfully not consumed in KVM) - Explicitly reject non-positive effective lengths during SNP's LAUNCH_UPDATE instead of subtly relying on guest_memfd to deal with them - Reload the pre-VMRUN TSC_AUX on #VMEXIT for SEV-ES guests, not the host's desired TSC_AUX, to fix a bug where KVM was keeping a different vCPU's TSC_AUX in the host MSR until return to userspace KVM (Intel): - Preparation for FRED support - Don't retry in TDX's anti-zero-step mitigation if the target memslot is invalid, i.e. is being deleted or moved, to fix a deadlock scenario similar to the aforementioned prefaulting case - Misc bugfixes and minor cleanups" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits) KVM: x86: Export KVM-internal symbols for sub-modules only KVM: x86: Drop pointless exports of kvm_arch_xxx() hooks KVM: x86: Move kvm_intr_is_single_vcpu() to lapic.c KVM: Export KVM-internal symbols for sub-modules only KVM: s390/vfio-ap: Use kvm_is_gpa_in_memslot() instead of open coded equivalent KVM: VMX: Make CR4.CET a guest owned bit KVM: selftests: Verify MSRs are (not) in save/restore list when (un)supported KVM: selftests: Add coverage for KVM-defined registers in MSRs test KVM: selftests: Add KVM_{G,S}ET_ONE_REG coverage to MSRs test KVM: selftests: Extend MSRs test to validate vCPUs without supported features KVM: selftests: Add support for MSR_IA32_{S,U}_CET to MSRs test KVM: selftests: Add an MSR test to exercise guest/host and read/write KVM: x86: Define AMD's #HV, #VC, and #SX exception vectors KVM: x86: Define Control Protection Exception (#CP) vector KVM: x86: Add human friendly formatting for #XM, and #VE KVM: SVM: Enable shadow stack virtualization for SVM KVM: SEV: Synchronize MSR_IA32_XSS from the GHCB when it's valid KVM: SVM: Pass through shadow stack MSRs as appropriate KVM: SVM: Update dump_vmcb with shadow stack save area additions KVM: nSVM: Save/load CET Shadow Stack state to/from vmcb12/vmcb02 ...
2025-10-03Merge tag 'for-6.18/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: - a new dm-pcache target for read/write caching on persistent memory - fix typos in docs - misc small refactoring - mark dm-error with DM_TARGET_PASSES_INTEGRITY - dm-request-based: fix NULL pointer dereference and quiesce_depth out of sync - dm-linear: optimize REQ_PREFLUSH - dm-vdo: return error on corrupted metadata - dm-integrity: support asynchronous hash interface * tag 'for-6.18/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (27 commits) dm raid: use proper md_ro_state enumerators dm-integrity: prefer synchronous hash interface dm-integrity: enable asynchronous hash interface dm-integrity: rename internal_hash dm-integrity: add the "offset" argument dm-integrity: allocate the recalculate buffer with kmalloc dm-integrity: introduce integrity_kmap and integrity_kunmap dm-integrity: replace bvec_kmap_local with kmap_local_page dm-integrity: use internal variable for digestsize dm vdo: return error on corrupted metadata in start_restoring_volume functions dm vdo: Update code to use mem_is_zero dm: optimize REQ_PREFLUSH with data when using the linear target dm-pcache: use int type to store negative error codes dm: fix "writen"->"written" dm-pcache: cleanup: fix coding style report by checkpatch.pl dm-pcache: remove ctrl_lock for pcache_cache_segment dm: fix NULL pointer dereference in __dm_suspend() dm: fix queue start/stop imbalance under suspend/load/resume races dm-pcache: add persistent cache target in device-mapper dm error: mark as DM_TARGET_PASSES_INTEGRITY ...