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* zswap: memcg accountingJohannes Weiner2022-05-191-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Applications can currently escape their cgroup memory containment when zswap is enabled. This patch adds per-cgroup tracking and limiting of zswap backend memory to rectify this. The existing cgroup2 memory.stat file is extended to show zswap statistics analogous to what's in meminfo and vmstat. Furthermore, two new control files, memory.zswap.current and memory.zswap.max, are added to allow tuning zswap usage on a per-workload basis. This is important since not all workloads benefit from zswap equally; some even suffer compared to disk swap when memory contents don't compress well. The optimal size of the zswap pool, and the threshold for writeback, also depends on the size of the workload's warm set. The implementation doesn't use a traditional page_counter transaction. zswap is unconventional as a memory consumer in that we only know the amount of memory to charge once expensive compression has occurred. If zwap is disabled or the limit is already exceeded we obviously don't want to compress page upon page only to reject them all. Instead, the limit is checked against current usage, then we compress and charge. This allows some limit overrun, but not enough to matter in practice. [hannes@cmpxchg.org: fix for CONFIG_SLOB builds] Link: https://lkml.kernel.org/r/YnwD14zxYjUJPc2w@cmpxchg.org [hannes@cmpxchg.org: opt out of cgroups v1] Link: https://lkml.kernel.org/r/Yn6it9mBYFA+/lTb@cmpxchg.org Link: https://lkml.kernel.org/r/20220510152847.230957-7-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm: zswap: add basic meminfo and vmstat coverageJohannes Weiner2022-05-191-0/+6
| | | | | | | | | | | | | | | | | | | | | Currently it requires poking at debugfs to figure out the size and population of the zswap cache on a host. There are no counters for reads and writes against the cache. As a result, it's difficult to understand zswap behavior on production systems. Print zswap memory consumption and how many pages are zswapped out in /proc/meminfo. Count zswapouts and zswapins in /proc/vmstat. Link: https://lkml.kernel.org/r/20220510152847.230957-6-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: Shakeel Butt <shakeelb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Documentation: filesystems: proc: update meminfo sectionJohannes Weiner2022-05-191-56/+92
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "zswap: accounting & cgroup control", v2. Zswap can consume nearly a quarter of RAM in the default configuration, yet it's neither listed in /proc/meminfo, nor is it accounted and manageable on a per-cgroup basis. This makes reasoning about the memory situation on a host in general rather difficult. On shared/cgrouped hosts, the consequences are worse. First, workloads can escape memory containment and cause resource priority inversions: a lo-pri group can fill the global zswap pool and force a hi-pri group out to disk. Second, not all workloads benefit from zswap equally. Some even suffer when memory contents compress poorly, and are better off going to disk swap directly. On a host with mixed workloads, it's currently not possible to enable zswap for one workload but not for the other. This series implements the missing global accounting as well as cgroup tracking & control for zswap backing memory: - Patch 1 refreshes the very out-of-date meminfo documentation in Documentation/filesystems/proc.rst. - Patches 2-4 clean up related and adjacent options in Kconfig. Not actual dependencies, just things I noticed during development. - Patch 5 adds meminfo and vmstat coverage for zswap consumption and activity. - Patch 6 implements per-cgroup tracking & control of zswap memory. This patch (of 6): Add new entries. Minor corrections and cleanups. [hannes@cmpxchg.org: fix htmldocs warnings] Link: https://lkml.kernel.org/r/Ynve8dg4zJyhH2gW@cmpxchg.org [hannes@cmpxchg.org: change `Unevictable' wording, per David] Link: https://lkml.kernel.org/r/YnwFraZlVWQoCjz3@cmpxchg.org Link: https://lkml.kernel.org/r/20220510152847.230957-1-hannes@cmpxchg.org Link: https://lkml.kernel.org/r/20220510152847.230957-2-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Roman Gushchin <guro@fb.com> Cc: Seth Jennings <sjenning@redhat.com> Cc: Shakeel Butt <shakeelb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/memcontrol: export memcg->watermark via sysfs for v2 memcgGanesan Rajagopal2022-05-141-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | We run a lot of automated tests when building our software and run into OOM scenarios when the tests run unbounded. v1 memcg exports memcg->watermark as "memory.max_usage_in_bytes" in sysfs. We use this metric to heuristically limit the number of tests that can run in parallel based on per test historical data. This metric is currently not exported for v2 memcg and there is no other easy way of getting this information. getrusage() syscall returns "ru_maxrss" which can be used as an approximation but that's the max RSS of a single child process across all children instead of the aggregated max for all child processes. The only work around is to periodically poll "memory.current" but that's not practical for short-lived one-off cgroups. Hence, expose memcg->watermark as "memory.peak" for v2 memcg. Link: https://lkml.kernel.org/r/20220507050916.GA13577@us192.sjc.aristanetworks.com Signed-off-by: Ganesan Rajagopal <rganesan@arista.com> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm: hugetlb_vmemmap: add hugetlb_optimize_vmemmap sysctlMuchun Song2022-05-141-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We must add hugetlb_free_vmemmap=on (or "off") to the boot cmdline and reboot the server to enable or disable the feature of optimizing vmemmap pages associated with HugeTLB pages. However, rebooting usually takes a long time. So add a sysctl to enable or disable the feature at runtime without rebooting. Why we need this? There are 3 use cases. 1) The feature of minimizing overhead of struct page associated with each HugeTLB is disabled by default without passing "hugetlb_free_vmemmap=on" to the boot cmdline. When we (ByteDance) deliver the servers to the users who want to enable this feature, they have to configure the grub (change boot cmdline) and reboot the servers, whereas rebooting usually takes a long time (we have thousands of servers). It's a very bad experience for the users. So we need a approach to enable this feature after rebooting. This is a use case in our practical environment. 2) Some use cases are that HugeTLB pages are allocated 'on the fly' instead of being pulled from the HugeTLB pool, those workloads would be affected with this feature enabled. Those workloads could be identified by the characteristics of they never explicitly allocating huge pages with 'nr_hugepages' but only set 'nr_overcommit_hugepages' and then let the pages be allocated from the buddy allocator at fault time. We can confirm it is a real use case from the commit 099730d67417. For those workloads, the page fault time could be ~2x slower than before. We suspect those users want to disable this feature if the system has enabled this before and they don't think the memory savings benefit is enough to make up for the performance drop. 3) If the workload which wants vmemmap pages to be optimized and the workload which wants to set 'nr_overcommit_hugepages' and does not want the extera overhead at fault time when the overcommitted pages be allocated from the buddy allocator are deployed in the same server. The user could enable this feature and set 'nr_hugepages' and 'nr_overcommit_hugepages', then disable the feature. In this case, the overcommited HugeTLB pages will not encounter the extra overhead at fault time. Link: https://lkml.kernel.org/r/20220512041142.39501-5-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Iurii Zaikin <yzaikin@google.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: David Hildenbrand <david@redhat.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm: hugetlb_vmemmap: use kstrtobool for hugetlb_vmemmap param parsingMuchun Song2022-05-141-3/+3
| | | | | | | | | | | | | | | | | | | Use kstrtobool rather than open coding "on" and "off" parsing in mm/hugetlb_vmemmap.c, which is more powerful to handle all kinds of parameters like 'Yy1Nn0' or [oO][NnFf] for "on" and "off". Link: https://lkml.kernel.org/r/20220512041142.39501-4-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Hildenbrand <david@redhat.com> Cc: Iurii Zaikin <yzaikin@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <keescook@chromium.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Documentation/vm: rework "Temporary Virtual Mappings" sectionFabio M. De Francesco2022-05-141-11/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Extend and rework the "Temporary Virtual Mappings" section of the highmem.rst documentation. Despite the local kmaps were introduced by Thomas Gleixner in October 2020, documentation was still missing information about them. These additions rely largely on Gleixner's patches, Jonathan Corbet's LWN articles, comments by Ira Weiny and Matthew Wilcox, and in-code comments from ./include/linux/highmem.h. 1) Add a paragraph to document kmap_local_page(). 2) Reorder the list of functions by decreasing order of preference of use. 3) Rework part of the kmap() entry in list. Link: https://lkml.kernel.org/r/20220428212455.892-5-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Documentation/vm: move "Using kmap-atomic" to highmem.hFabio M. De Francesco2022-05-141-35/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The use of kmap_atomic() is new code is being deprecated in favor of kmap_local_page(). For this reason the "Using kmap_atomic" section in highmem.rst is obsolete and unnecessary, but it can still help developers if it were moved to kdocs in highmem.h. Therefore, move the relevant parts of this section from highmem.rst and merge them with the kdocs in highmem.h. Link: https://lkml.kernel.org/r/20220428212455.892-4-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Documentation/vm: include kdocs from highmem*.h into highmem.rstFabio M. De Francesco2022-05-141-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | kernel-docs that are in include/linux/highmem.h and in include/linux/highmem-internal.h should be included in highmem.rst. Use kdocs directives to include the above-mentioned comments into highmem.rst. Link: https://lkml.kernel.org/r/20220428212455.892-3-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Suggested-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* kasan: move boot parameters section in documentationAndrey Konovalov2022-05-131-41/+41
| | | | | | | | | | | | | | | | Move the "Boot parameters" section in KASAN documentation next to the section that describes KASAN build options. No content changes. Link: https://lkml.kernel.org/r/870628e1293b4f44edf7cbcb92374ff9eb7503d7.1652203271.git.andreyknvl@google.com Link: https://lkml.kernel.org/r/ec9c923f35e7c5312836c4624a7f317dc1ee2c1c.1652123204.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* kasan: update documentationAndrey Konovalov2022-05-131-60/+90
| | | | | | | | | | | | | | | | | | | Do assorted clean-ups and improvements to KASAN documentation, including: - Describe each mode in a dedicated paragraph. - Split out a Support section that describes in details which compilers, architectures and memory types each mode requires/supports. - Capitalize the first letter in the names of each KASAN mode. [andreyknvl@google.com: rewording, per Marco] Link: https://lkml.kernel.org/r/896b2d914d6b50d677fd7b38f76967cc705c01ba.1652203271.git.andreyknvl@google.com Link: https://lkml.kernel.org/r/5bd58ebebf066593ce0e1d265d60278b5f5a1874.1652123204.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* docs: vm/page_owner: tweak literal block in STANDARD FORMAT SPECIFIERSAkira Yokosawa2022-05-131-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A semantic conflict between commit 5603f9bdea68 ("docs: vm/page_owner: use literal blocks for param description") and a change queued for v5.19 authored by Jiajian Ye ("tools/vm/page_owner_sort.c: support sorting blocks by multiple keys") results in a warning from "make htmldocs" saying: [...]/vm/page_owner.rst:176: WARNING: Literal block expected; none found. This is because a literal block in ReST ends at a line which has the same indent as the paragraph preceding it. In this case the one with no indent. Indent the two "For --xxxx option:" lines by two columns and make the whole section a literal block. While at it, fix indents by white spaces of "ator" keys. Link: https://lkml.kernel.org/r/fdfecc82-d41e-6d8a-738d-4beb6faa27fb@gmail.com Signed-of-by: Akira Yokosawa <akiyks@gmail.com> Reported-by: Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn> Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Yongqiang Liu <liuyongqiang13@huawei.com> Cc: Yuhong Feng <yuhongf@szu.edu.cn> Cc: Haowen Bai <baihaowen@meizu.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Docs/admin-guide/mm/damon/reclaim: document 'commit_inputs' parameterSeongJae Park2022-05-131-0/+11
| | | | | | | | | This commit documents the new DAMON_RECLAIM parameter, 'commit_inputs' in its usage document. Link: https://lkml.kernel.org/r/20220429160606.127307-15-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Docs/{ABI,admin-guide}/damon: Update for 'state' sysfs file input keyword, ↵SeongJae Park2022-05-132-7/+9
| | | | | | | | | | | 'commit' This commit documents the newly added 'state' sysfs file input keyword, 'commit', which allows online tuning of DAMON contexts. Link: https://lkml.kernel.org/r/20220429160606.127307-13-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Docs/{ABI,admin-guide}/damon: update for fixed virtual address ranges monitoringSeongJae Park2022-05-132-9/+19
| | | | | | | | | | This commit documents the user space support of the newly added monitoring operations set for fixed virtual address ranges monitoring, namely 'fvaddr', on the ABI and usage documents for DAMON. Link: https://lkml.kernel.org/r/20220426231750.48822-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Docs/{ABI,admin-guide}/damon: document 'avail_operations' sysfs fileSeongJae Park2022-05-132-7/+21
| | | | | | | | | This commit updates the DAMON ABI and usage documents for the new sysfs file, 'avail_operations'. Link: https://lkml.kernel.org/r/20220426203843.45238-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* doc: update documentation for swap_activate and swap_rwNeilBrown2022-05-102-11/+24
| | | | | | | | | | | | | | | | | This documentation for ->swap_activate() has been out-of-date for a long time. This patch updates it to match recent changes, and adds documentation for the associated ->swap_rw() Link: https://lkml.kernel.org/r/164859778126.29473.6778751233552859461.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* memcg: introduce per-memcg reclaim interfaceShakeel Butt2022-04-291-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch series adds a memory.reclaim proactive reclaim interface. The rationale behind the interface and how it works are in the first patch. This patch (of 4): Introduce a memcg interface to trigger memory reclaim on a memory cgroup. Use case: Proactive Reclaim --------------------------- A userspace proactive reclaimer can continuously probe the memcg to reclaim a small amount of memory. This gives more accurate and up-to-date workingset estimation as the LRUs are continuously sorted and can potentially provide more deterministic memory overcommit behavior. The memory overcommit controller can provide more proactive response to the changing behavior of the running applications instead of being reactive. A userspace reclaimer's purpose in this case is not a complete replacement for kswapd or direct reclaim, it is to proactively identify memory savings opportunities and reclaim some amount of cold pages set by the policy to free up the memory for more demanding jobs or scheduling new jobs. A user space proactive reclaimer is used in Google data centers. Additionally, Meta's TMO paper recently referenced a very similar interface used for user space proactive reclaim: https://dl.acm.org/doi/pdf/10.1145/3503222.3507731 Benefits of a user space reclaimer: ----------------------------------- 1) More flexible on who should be charged for the cpu of the memory reclaim. For proactive reclaim, it makes more sense to be centralized. 2) More flexible on dedicating the resources (like cpu). The memory overcommit controller can balance the cost between the cpu usage and the memory reclaimed. 3) Provides a way to the applications to keep their LRUs sorted, so, under memory pressure better reclaim candidates are selected. This also gives more accurate and uptodate notion of working set for an application. Why memory.high is not enough? ------------------------------ - memory.high can be used to trigger reclaim in a memcg and can potentially be used for proactive reclaim. However there is a big downside in using memory.high. It can potentially introduce high reclaim stalls in the target application as the allocations from the processes or the threads of the application can hit the temporary memory.high limit. - Userspace proactive reclaimers usually use feedback loops to decide how much memory to proactively reclaim from a workload. The metrics used for this are usually either refaults or PSI, and these metrics will become messy if the application gets throttled by hitting the high limit. - memory.high is a stateful interface, if the userspace proactive reclaimer crashes for any reason while triggering reclaim it can leave the application in a bad state. - If a workload is rapidly expanding, setting memory.high to proactively reclaim memory can result in actually reclaiming more memory than intended. The benefits of such interface and shortcomings of existing interface were further discussed in this RFC thread: https://lore.kernel.org/linux-mm/5df21376-7dd1-bf81-8414-32a73cea45dd@google.com/ Interface: ---------- Introducing a very simple memcg interface 'echo 10M > memory.reclaim' to trigger reclaim in the target memory cgroup. The interface is introduced as a nested-keyed file to allow for future optional arguments to be easily added to configure the behavior of reclaim. Possible Extensions: -------------------- - This interface can be extended with an additional parameter or flags to allow specifying one or more types of memory to reclaim from (e.g. file, anon, ..). - The interface can also be extended with a node mask to reclaim from specific nodes. This has use cases for reclaim-based demotion in memory tiering systens. - A similar per-node interface can also be added to support proactive reclaim and reclaim-based demotion in systems without memcg. - Add a timeout parameter to make it easier for user space to call the interface without worrying about being blocked for an undefined amount of time. For now, let's keep things simple by adding the basic functionality. [yosryahmed@google.com: worked on versions v2 onwards, refreshed to current master, updated commit message based on recent discussions and use cases] Link: https://lkml.kernel.org/r/20220425190040.2475377-1-yosryahmed@google.com Link: https://lkml.kernel.org/r/20220425190040.2475377-2-yosryahmed@google.com Signed-off-by: Shakeel Butt <shakeelb@google.com> Co-developed-by: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Wei Xu <weixugc@google.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: David Rientjes <rientjes@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Cc: Yu Zhao <yuzhao@google.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Greg Thelen <gthelen@google.com> Cc: Chen Wandun <chenwandun@huawei.com> Cc: Vaibhav Jain <vaibhav@linux.ibm.com> Cc: "Michal Koutn" <mkoutny@suse.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* zram: add a huge_idle writeback modeBrian Geffon2022-04-291-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Today it's only possible to write back as a page, idle, or huge. A user might want to writeback pages which are huge and idle first as these idle pages do not require decompression and make a good first pass for writeback. Idle writeback specifically has the advantage that a refault is unlikely given that the page has been swapped for some amount of time without being refaulted. Huge writeback has the advantage that you're guaranteed to get the maximum benefit from a single page writeback, that is, you're reclaiming one full page of memory. Pages which are compressed in zram being written back result in some benefit which is always less than a page size because of the fact that it was compressed. The primary use of this is for minimizing refaults in situations where the device has to be sensitive to storage endurance. On ChromeOS we have devices with slow eMMC and repeated writes and refaults can negatively affect performance and endurance. Link: https://lkml.kernel.org/r/20220322215821.1196994-1-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/vmstat: add events for ksm cowYang Yang2022-04-291-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | Users may use ksm by calling madvise(, , MADV_MERGEABLE) when they want to save memory, it's a tradeoff by suffering delay on ksm cow. Users can get to know how much memory ksm saved by reading /sys/kernel/mm/ksm/pages_sharing, but they don't know what's the costs of ksm cow, and this is important of some delay sensitive tasks. So add ksm cow events to help users evaluate whether or how to use ksm. Also update Documentation/admin-guide/mm/ksm.rst with new added events. Link: https://lkml.kernel.org/r/20220331035616.2390805-1-yang.yang29@zte.com.cn Signed-off-by: Yang Yang <yang.yang29@zte.com.cn> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: xu xin <xu.xin16@zte.com.cn> Reviewed-by: Ran Xiaokai <ran.xiaokai@zte.com.cn> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Saravanan D <saravanand@fb.com> Cc: Minchan Kim <minchan@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/sparse-vmemmap: improve memory savings for compound devmapsJoao Martins2022-04-291-3/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A compound devmap is a dev_pagemap with @vmemmap_shift > 0 and it means that pages are mapped at a given huge page alignment and utilize uses compound pages as opposed to order-0 pages. Take advantage of the fact that most tail pages look the same (except the first two) to minimize struct page overhead. Allocate a separate page for the vmemmap area which contains the head page and separate for the next 64 pages. The rest of the subsections then reuse this tail vmemmap page to initialize the rest of the tail pages. Sections are arch-dependent (e.g. on x86 it's 64M, 128M or 512M) and when initializing compound devmap with big enough @vmemmap_shift (e.g. 1G PUD) it may cross multiple sections. The vmemmap code needs to consult @pgmap so that multiple sections that all map the same tail data can refer back to the first copy of that data for a given gigantic page. On compound devmaps with 2M align, this mechanism lets 6 pages be saved out of the 8 necessary PFNs necessary to set the subsection's 512 struct pages being mapped. On a 1G compound devmap it saves 4094 pages. Altmap isn't supported yet, given various restrictions in altmap pfn allocator, thus fallback to the already in use vmemmap_populate(). It is worth noting that altmap for devmap mappings was there to relieve the pressure of inordinate amounts of memmap space to map terabytes of pmem. With compound pages the motivation for altmaps for pmem gets reduced. Link: https://lkml.kernel.org/r/20220420155310.9712-5-joao.m.martins@oracle.com Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/hugetlb_vmemmap: move comment block to Documentation/vmJoao Martins2022-04-292-0/+174
| | | | | | | | | | | | | | | | | | | | | In preparation for device-dax for using hugetlbfs compound page tail deduplication technique, move the comment block explanation into a common place in Documentation/vm. Link: https://lkml.kernel.org/r/20220420155310.9712-4-joao.m.martins@oracle.com Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Suggested-by: Dan Williams <dan.j.williams@intel.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jane Chu <jane.chu@oracle.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm: hugetlb_vmemmap: cleanup CONFIG_HUGETLB_PAGE_FREE_VMEMMAP*Muchun Song2022-04-292-3/+3
| | | | | | | | | | | | | The word of "free" is not expressive enough to express the feature of optimizing vmemmap pages associated with each HugeTLB, rename this keywork to "optimize". In this patch , cheanup configs to make code more expressive. Link: https://lkml.kernel.org/r/20220404074652.68024-4-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Documentation/sysctl: document page_lock_unfairnessJoel Savitz2022-04-291-0/+9
| | | | | | | | | | | | | | | | | | | | commit 5ef64cc8987a ("mm: allow a controlled amount of unfairness in the page lock") introduced a new systctl but no accompanying documentation. Add a simple entry to the documentation. Link: https://lkml.kernel.org/r/20220325164437.120246-1-jsavitz@redhat.com Signed-off-by: Joel Savitz <jsavitz@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: "zhangyi (F)" <yi.zhang@huawei.com> Cc: Charan Teja Reddy <charante@codeaurora.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* tools/vm/page_owner_sort.c: provide allocator labelling and update --cull ↵Yixuan Cao2022-04-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and --sort options An application is suspected of having memory leak when its memory consumption is high and keeps increasing. There are several commonly used memory allocators: slab, cma, vmalloc, etc. The memory leak identification can be sped up if the page information allocated by an allocator can be analyzed separately. This patch provides supports for memory allocator labelling for slab, vmalloc, and cma. The pages allocated by slab and cma can be confirmed from the "PFN" line according to the kernel codes, and the label of the vmalloc allocator can be obtained by analyzing the stack trace. Thanks for Vlastimil Babka's constructive suggestions. Based on Yinan Zhang's study, the call chain of vmalloc() is vmalloc() -> ... -> __vmalloc_node_range() -> __vmalloc_area_node(). __vmalloc_area_node() requests memory through the interface of buddy allocation system. In the current version, __vmalloc_area_node() uses four interfaces: alloc_pages_bulk_array_mempolicy(), alloc_pages_bulk_array_node(), alloc_pages() and alloc_pages_node(). By disassembling the code, we find that __vmalloc_area_node() is expanded in __vmalloc_node_range(). So __vmalloc_area_node is not in the stack trace. On the test machine, the stack trace of pages allocated by vmalloc has the following four forms: __alloc_pages_bulk+0x230/0x6a0 __vmalloc_node_range+0x19c/0x598 alloc_pages_bulk_array_mempolicy+0xbc/0x278 __vmalloc_node_range+0x1e8/0x598 __alloc_pages+0x160/0x2b0 __vmalloc_node_range+0x234/0x598 alloc_pages+0xac/0x150 __vmalloc_node_range+0x44c/0x598 Therefore, in two consecutive lines of stacktrace, if the first line contains the word "alloc_pages" and the second line contains the word "__vmalloc_node_range", it can be determined that the page is allocated by vmalloc. And the function offset and size are not the same on different machines, so there is no need to match them. At the same time, this patch updates the --cull and --sort options to support allocator-based merge statistics and sorting. The added functions are fully compatible with the original work. When using, you can use "allocator", or abbreviated as "ator". Relevant updates have also been made in the documentation(Documentation/vm/page_owner.rst). Example: ./page_owner_sort <input> <output> --cull=st,pid,name,allocator ./page_owner_sort <input> <output> --sort=ator,pid,name This work is coauthored by Jiajian Ye, Yinan Zhang, Shenghong Han, Chongxi Zhao, Yuhong Feng and Yongqiang Liu. Link: https://lkml.kernel.org/r/20220410132932.9402-1-caoyixuan2019@email.szu.edu.cn Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Cc: Haowen Bai <baihaowen@meizu.com> Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn> Cc: Sean Anderson <seanga2@gmail.com> Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Cc: Yongqiang Liu <liuyongqiang13@huawei.com> Cc: Yuhong Feng <yuhongf@szu.edu.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* tools/vm/page_owner_sort.c: support sorting blocks by multiple keysJiajian Ye2022-04-291-1/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When viewing page owner information, we may want to sort blocks of information by multiple keys, since one single key does not uniquely identify a block. Therefore, following adjustments are made: 1. Add a new --sort option to support sorting blocks of information by multiple keys. ./page_owner_sort <input> <output> --sort=<order> ./page_owner_sort <input> <output> --sort <order> <order> is a single argument in the form of a comma-separated list, which offers a way to specify sorting order. Sorting syntax is [+|-]key[,[+|-]key[,...]]. The ascending or descending order can be specified by adding the + (ascending, default) or - (descend -ing) prefix to the key: ./page_owner_sort <input> <output> [option] --sort -key1,+key2,key3... For example, to sort the blocks first by task command name in lexicographic order and then by pid in ascending numerical order, use the following: ./page_owner_sort <input> <output> --sort=name,+pid To sort the blocks first by pid in ascending order and then by timestamp of the page when it is allocated in descending order, use the following: ./page_owner_sort <input> <output> --sort=pid,-alloc_ts 2. Add explanations of a newly added --sort option in the function usage() and the document(Documentation/vm/page_owner.rst). This work is coauthored by Yixuan Cao Shenghong Han Yinan Zhang Chongxi Zhao Yuhong Feng Yongqiang Liu Link: https://lkml.kernel.org/r/20220401024856.767-3-yejiajian2018@email.szu.edu.cn Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn> Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Yongqiang Liu <liuyongqiang13@huawei.com> Cc: Yuhong Feng <yuhongf@szu.edu.cn> Cc: Haowen Bai <baihaowen@meizu.com> Cc: Sean Anderson <seanga2@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* tools/vm/page_owner_sort.c: support for multi-value selection in single argumentJiajian Ye2022-04-291-5/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When viewing page owner information, we may want to select blocks whose PID/TGID/TASK_COMM_NAME appears in a user-specified list for data analysis and aggregation. But currently page_owner_sort only supports selecting blocks associated with only one specified PID/TGID/TASK_COMM_NAME. Therefore, following adjustments are made to fix the problem: 1. Enhance selecting function to support the selection of multiple PIDs/TGIDs/TASK_COMM_NAMEs. The enhanced usages are as follows: --pid <pidlist> Select by pid. This selects the blocks whose PID numbers appear in <pidlist>. --tgid <tgidlist> Select by tgid. This selects the blocks whose TGID numbers appear in <tgidlist>. --name <cmdlist> Select by task command name. This selects the blocks whose task command name appear in <cmdlist>. Where <pidlist>, <tgidlist>, <cmdlist> are single arguments in the form of a comma-separated list,which offers a way to specify individual selecting rules. For example, if you want to select blocks whose tgids are 1, 2 or 3, you have to use 4 commands as follows: ./page_owner_sort <input> <output1> --tgid=1 ./page_owner_sort <input> <output2> --tgid=2 ./page_owner_sort <input> <output3> --tgid=3 cat <output1> <output2> <output3> > <output> With this patch, you can use only 1 command to obtain the same result as above: ./page_owner_sort <input> <output1> --tgid=1,2,3 2. Update explanations of --pid, --tgid and --name in the function usage() and the document(Documents/vm/page_owner.rst). This work is coauthored by Yixuan Cao Shenghong Han Yinan Zhang Chongxi Zhao Yuhong Feng Yongqiang Liu Link: https://lkml.kernel.org/r/20220401024856.767-2-yejiajian2018@email.szu.edu.cn Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn> Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn> Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Yongqiang Liu <liuyongqiang13@huawei.com> Cc: Yuhong Feng <yuhongf@szu.edu.cn> Cc: Haowen Bai <baihaowen@meizu.com> Cc: Sean Anderson <seanga2@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'net-5.18-rc5' of ↵Linus Torvalds2022-04-281-21/+14
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bluetooth, bpf and netfilter. Current release - new code bugs: - bridge: switchdev: check br_vlan_group() return value - use this_cpu_inc() to increment net->core_stats, fix preempt-rt Previous releases - regressions: - eth: stmmac: fix write to sgmii_adapter_base Previous releases - always broken: - netfilter: nf_conntrack_tcp: re-init for syn packets only, resolving issues with TCP fastopen - tcp: md5: fix incorrect tcp_header_len for incoming connections - tcp: fix F-RTO may not work correctly when receiving DSACK - tcp: ensure use of most recently sent skb when filling rate samples - tcp: fix potential xmit stalls caused by TCP_NOTSENT_LOWAT - virtio_net: fix wrong buf address calculation when using xdp - xsk: fix forwarding when combining copy mode with busy poll - xsk: fix possible crash when multiple sockets are created - bpf: lwt: fix crash when using bpf_skb_set_tunnel_key() from bpf_xmit lwt hook - sctp: null-check asoc strreset_chunk in sctp_generate_reconf_event - wireguard: device: check for metadata_dst with skb_valid_dst() - netfilter: update ip6_route_me_harder to consider L3 domain - gre: make o_seqno start from 0 in native mode - gre: switch o_seqno to atomic to prevent races in collect_md mode Misc: - add Eric Dumazet to networking maintainers - dt: dsa: realtek: remove realtek,rtl8367s string - netfilter: flowtable: Remove the empty file" * tag 'net-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (65 commits) tcp: fix F-RTO may not work correctly when receiving DSACK Revert "ibmvnic: Add ethtool private flag for driver-defined queue limits" net: enetc: allow tc-etf offload even with NETIF_F_CSUM_MASK ixgbe: ensure IPsec VF<->PF compatibility MAINTAINERS: Update BNXT entry with firmware files netfilter: nft_socket: only do sk lookups when indev is available net: fec: add missing of_node_put() in fec_enet_init_stop_mode() bnx2x: fix napi API usage sequence tls: Skip tls_append_frag on zero copy size Add Eric Dumazet to networking maintainers netfilter: conntrack: fix udp offload timeout sysctl netfilter: nf_conntrack_tcp: re-init for syn packets only net: dsa: lantiq_gswip: Don't set GSWIP_MII_CFG_RMII_CLK net: Use this_cpu_inc() to increment net->core_stats Bluetooth: hci_sync: Cleanup hci_conn if it cannot be aborted Bluetooth: hci_event: Fix creating hci_conn object on error status Bluetooth: hci_event: Fix checking for invalid handle on error status ice: fix use-after-free when deinitializing mailbox snapshot ice: wait 5 s for EMP reset after firmware flash ice: Protect vf_state check by cfg_lock in ice_vc_process_vf_msg() ...
| * dt-bindings: net: dsa: realtek: cleanup compatible stringsLuiz Angelo Daros de Luca2022-04-231-21/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compatible strings are used to help the driver find the chip ID/version register for each chip family. After that, the driver can setup the switch accordingly. Keep only the first supported model for each family as a compatible string and reference other chip models in the description. The removed compatible strings have never been used in a released kernel. Link: https://lore.kernel.org/netdev/20220414014055.m4wbmr7tdz6hsa3m@bang-olufsen.dk/ Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Arınç ÜNAL <arinc.unal@arinc9.com> Reviewed-by: Alvin Šipraga <alsi@bang-olufsen.dk> Link: https://lore.kernel.org/r/20220418233558.13541-1-luizluca@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | Merge tag 'regulator-fix-v5.18-rc4' of ↵Linus Torvalds2022-04-281-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator Pull regulator fix from Mark Brown: "A minor fix for the DT binding documentation of the rt5190a driver" * tag 'regulator-fix-v5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: regulator: dt-bindings: Revise the rt5190a buck/ldo description
| * | regulator: dt-bindings: Revise the rt5190a buck/ldo descriptionChiYuan Huang2022-04-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Revise the rt5190a bucks and ldo property description. Signed-off-by: ChiYuan Huang <cy_huang@richtek.com> Link: https://lore.kernel.org/r/1650610255-6180-1-git-send-email-u0084500@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
* | | docs: vm/page_owner: use literal blocks for param descriptionAkira Yokosawa2022-04-271-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sphinx generates hard-to-read lists of parameters at the bottom of the page. Fix them by putting literal-block markers of "::" in front of them. Link: https://lkml.kernel.org/r/cfd3bcc0-b51d-0c68-c065-ca1c4c202447@gmail.com Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Fixes: 57f2b54a9379 ("Documentation/vm/page_owner.rst: update the documentation") Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn> Cc: Haowen Bai <baihaowen@meizu.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Alex Shi <seakeel@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge tag 'f2fs-fix-5.18' of ↵Linus Torvalds2022-04-251-70/+0
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs fixes from Jaegeuk Kim: "This includes major bug fixes introduced in 5.18-rc1 and 5.17+: - Remove obsolete whint_mode (5.18-rc1) - Fix IO split issue caused by op_flags change in f2fs (5.18-rc1) - Fix a wrong condition check to detect IO failure loop (5.18-rc1) - Fix wrong data truncation during roll-forward (5.17+)" * tag 'f2fs-fix-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: f2fs: should not truncate blocks during roll-forward recovery f2fs: fix wrong condition check when failing metapage read f2fs: keep io_flags to avoid IO split due to different op_flags in two fio holders f2fs: remove obsolete whint_mode
| * | | f2fs: remove obsolete whint_modeJaegeuk Kim2022-04-201-70/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes obsolete whint_mode. Fixes: 41d36a9f3e53 ("fs: remove kiocb.ki_hint") Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
* | | | Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds2022-04-231-1/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Fix some syzbot-detected bugs, as well as other bugs found by I/O injection testing. Change ext4's fallocate to consistently drop set[ug]id bits when an fallocate operation might possibly change the user-visible contents of a file. Also, improve handling of potentially invalid values in the the s_overhead_cluster superblock field to avoid ext4 returning a negative number of free blocks" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: jbd2: fix a potential race while discarding reserved buffers after an abort ext4: update the cached overhead value in the superblock ext4: force overhead calculation if the s_overhead_cluster makes no sense ext4: fix overhead calculation to account for the reserved gdt blocks ext4, doc: fix incorrect h_reserved size ext4: limit length to bitmap_maxbytes - blocksize in punch_hole ext4: fix use-after-free in ext4_search_dir ext4: fix bug_on in start_this_handle during umount filesystem ext4: fix symlink file size not match to file content ext4: fix fallocate to use file_modified to update permissions consistently
| * | | | ext4, doc: fix incorrect h_reserved sizewangjianjian (C)2022-04-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to document and code, ext4_xattr_header's size is 32 bytes, so h_reserved size should be 3. Signed-off-by: Wang Jianjian <wangjianjian3@huawei.com> Link: https://lore.kernel.org/r/92fcc3a6-7d77-8c09-4126-377fcb4c46a5@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
* | | | | Merge tag 'dmaengine-fix-5.18' of ↵Linus Torvalds2022-04-221-0/+1
|\ \ \ \ \ | |_|_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine Pull dmaengine fixes from Vinod Koul: "A bunch of driver fixes: - idxd device RO checks and device cleanup - dw-edma unaligned access and alignment - qcom: missing minItems in binding - mediatek pm usage fix - imx init script" * tag 'dmaengine-fix-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: dt-bindings: dmaengine: qcom: gpi: Add minItems for interrupts dmaengine: idxd: skip clearing device context when device is read-only dmaengine: idxd: add RO check for wq max_transfer_size write dmaengine: idxd: add RO check for wq max_batch_size write dmaengine: idxd: fix retry value to be constant for duration of function call dmaengine: idxd: match type for retries var in idxd_enqcmds() dmaengine: dw-edma: Fix inconsistent indenting dmaengine: dw-edma: Fix unaligned 64bit access dmaengine: mediatek:Fix PM usage reference leak of mtk_uart_apdma_alloc_chan_resources dmaengine: imx-sdma: Fix error checking in sdma_event_remap dma: at_xdmac: fix a missing check on list iterator dmaengine: imx-sdma: fix init of uart scripts dmaengine: idxd: fix device cleanup on disable
| * | | | dt-bindings: dmaengine: qcom: gpi: Add minItems for interruptsVinod Koul2022-04-201-0/+1
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the minItems for interrupts property as well. In the absence of this, we get warning if interrupts are less than 13 arch/arm64/boot/dts/qcom/qrb5165-rb5.dtb: dma-controller@800000: interrupts: [[0, 588, 4], [0, 589, 4], [0, 590, 4], [0, 591, 4], [0, 592, 4], [0, 593, 4], [0, 594, 4], [0, 595, 4], [0, 596, 4], [0, 597, 4]] is too short Signed-off-by: Vinod Koul <vkoul@kernel.org> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://lore.kernel.org/r/20220414064235.1182195-1-vkoul@kernel.org Signed-off-by: Vinod Koul <vkoul@kernel.org>
* | | | Merge tag 'net-5.18-rc4' of ↵Linus Torvalds2022-04-211-0/+7
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from xfrm and can. Current release - regressions: - rxrpc: restore removed timer deletion Current release - new code bugs: - gre: fix device lookup for l3mdev use-case - xfrm: fix egress device lookup for l3mdev use-case Previous releases - regressions: - sched: cls_u32: fix netns refcount changes in u32_change() - smc: fix sock leak when release after smc_shutdown() - xfrm: limit skb_page_frag_refill use to a single page - eth: atlantic: invert deep par in pm functions, preventing null derefs - eth: stmmac: use readl_poll_timeout_atomic() in atomic state Previous releases - always broken: - gre: fix skb_under_panic on xmit - openvswitch: fix OOB access in reserve_sfa_size() - dsa: hellcreek: calculate checksums in tagger - eth: ice: fix crash in switchdev mode - eth: igc: - fix infinite loop in release_swfw_sync - fix scheduling while atomic" * tag 'net-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (37 commits) drivers: net: hippi: Fix deadlock in rr_close() selftests: mlxsw: vxlan_flooding_ipv6: Prevent flooding of unwanted packets selftests: mlxsw: vxlan_flooding: Prevent flooding of unwanted packets nfc: MAINTAINERS: add Bug entry net: stmmac: Use readl_poll_timeout_atomic() in atomic state doc/ip-sysctl: add bc_forwarding netlink: reset network and mac headers in netlink_dump() net: mscc: ocelot: fix broken IP multicast flooding net: dsa: hellcreek: Calculate checksums in tagger net: atlantic: invert deep par in pm functions, preventing null derefs can: isotp: stop timeout monitoring when no first frame was sent bonding: do not discard lowest hash bit for non layer3+4 hashing net: lan966x: Make sure to release ptp interrupt ipv6: make ip6_rt_gc_expire an atomic_t net: Handle l3mdev in ip_tunnel_init_flow l3mdev: l3mdev_master_upper_ifindex_by_index_rcu should be using netdev_master_upper_dev_get_rcu net/sched: cls_u32: fix possible leak in u32_init_knode() net/sched: cls_u32: fix netns refcount changes in u32_change() powerpc: Update MAINTAINERS for ibmvnic and VAS net: restore alpha order to Ethernet devices in config ...
| * | | | doc/ip-sysctl: add bc_forwardingNicolas Dichtel2022-04-201-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's describe this sysctl. Fixes: 5cbf777cfdf6 ("route: add support for directed broadcast forwarding") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | | Merge tag 'erofs-for-5.18-rc4-fixes' of ↵Linus Torvalds2022-04-201-2/+3
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs fixes from Gao Xiang: "One patch to fix a use-after-free race related to the on-stack z_erofs_decompressqueue, which happens very rarely but needs to be fixed properly soon. The other patch fixes some sysfs Sphinx warnings" * tag 'erofs-for-5.18-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: Documentation/ABI: sysfs-fs-erofs: Fix Sphinx errors erofs: fix use-after-free of on-stack io[]
| * | | | | Documentation/ABI: sysfs-fs-erofs: Fix Sphinx errorsHans de Goede2022-04-151-2/+3
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the following warnings from "make htmldocs": Documentation/ABI/testing/sysfs-fs-erofs:10: ERROR: Unexpected indentation. WARNING: Block quote ends without a blank line; unexpected unindent. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20220324165918.22005-4-hdegoede@redhat.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
* | | | | Merge tag 'devicetree-fixes-for-5.18-2' of ↵Linus Torvalds2022-04-1728-165/+145
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux Pull devicetree fixes from Rob Herring: - Fix scalar property schemas with array constraints - Fix 'enum' lists with duplicate entries - Fix incomplete if/then/else schemas - Add Renesas RZ/V2L SoC support to Mali Bifrost binding - Maintainers update for Marvell irqchip * tag 'devicetree-fixes-for-5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: dt-bindings: display: panel-timing: Define a single type for properties dt-bindings: Fix array constraints on scalar properties dt-bindings: gpu: mali-bifrost: Document RZ/V2L SoC dt-bindings: net: snps: remove duplicate name dt-bindings: Fix 'enum' lists with duplicate entries dt-bindings: irqchip: mrvl,intc: refresh maintainers dt-bindings: Fix incomplete if/then/else schemas dt-bindings: power: renesas,apmu: Fix cpus property limits dt-bindings: extcon: maxim,max77843: fix ports type
| * | | | | dt-bindings: display: panel-timing: Define a single type for propertiesRob Herring2022-04-141-24/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's not good practice to define multiple types for the same property, so factor out the type reference making the properties always an uint32-array with a length of 1 or 3 items. Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Link: https://lore.kernel.org/r/20220413140016.3131013-1-robh@kernel.org
| * | | | | dt-bindings: Fix array constraints on scalar propertiesRob Herring2022-04-148-17/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Scalar properties shouldn't have array constraints (minItems, maxItems, items). These constraints can simply be dropped with any constraints under 'items' moved up a level. Cc: Agathe Porte <agathe.porte@nokia.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jean Delvare <jdelvare@suse.com> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org> Cc: Olivier Moysan <olivier.moysan@foss.st.com> Cc: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mark Brown <broonie@kernel.org> Cc: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Cc: Yunfei Dong <yunfei.dong@mediatek.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: linux-hwmon@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: linux-iio@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-remoteproc@vger.kernel.org Cc: linux-spi@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Mark Brown <broonie@kernel.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20220413140121.3132837-1-robh@kernel.org
| * | | | | dt-bindings: gpu: mali-bifrost: Document RZ/V2L SoCLad Prabhakar2022-04-061-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Renesas RZ/V2L SoC (a.k.a R9A07G054) has a Bifrost Mali-G31 GPU, add a compatible string for it. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20220308211543.3081-1-prabhakar.mahadev-lad.rj@bp.renesas.com
| * | | | | dt-bindings: net: snps: remove duplicate nameDongjin Yang2022-04-061-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | snps,dwmac has duplicated name for loongson,ls2k-dwmac and loongson,ls7a-dwmac. Signed-off-by: Dongjin Yang <dj76.yang@samsung.com> Fixes: 68277749a013 ("dt-bindings: dwmac: Add bindings for new Loongson SoC and bridge chip") Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20220404022857epcms1p6e6af1a6a86569f339e50c318abde7d3c@epcms1p6
| * | | | | dt-bindings: Fix 'enum' lists with duplicate entriesRob Herring2022-04-045-10/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no reason to list the same value twice in an 'enum'. Fix all the occurrences in the tree. A meta-schema change will catch future ones. Cc: Krzysztof Kozlowski <krzk+dt@kernel.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Charles Keepax <ckeepax@opensource.cirrus.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Sebastian Reichel <sre@kernel.org> Cc: Tony Lindgren <tony@atomide.com> Cc: Yunfei Dong <yunfei.dong@mediatek.com> Cc: - <patches@opensource.cirrus.com> Cc: linux-media@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: linux-gpio@vger.kernel.org Cc: linux-pm@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com> Link: https://lore.kernel.org/r/20220401141247.2993925-1-robh@kernel.org
| * | | | | dt-bindings: irqchip: mrvl,intc: refresh maintainersKrzysztof Kozlowski2022-04-041-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jason's email bounces and his address was dropped from maintainers in commit 509920aee72a ("MAINTAINERS: Move Jason Cooper to CREDITS"), so drop him here too. Switch other maintainers from IRQCHIP subsystem maintainers to Marvell Orion platform maintainers because its a bigger chance they know the hardware. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20220317142952.479413-1-krzysztof.kozlowski@canonical.com
| * | | | | dt-bindings: Fix incomplete if/then/else schemasRob Herring2022-04-0411-103/+107
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A recent review highlighted that the json-schema meta-schema allows any combination of if/then/else schema keywords even though if, then or else by themselves makes little sense. With an added meta-schema to only allow valid combinations, there's a handful of schemas found which need fixing in a variety of ways. Incorrect indentation is the most common issue. Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Michael Hennerich <Michael.Hennerich@analog.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org> Cc: Olivier Moysan <olivier.moysan@foss.st.com> Cc: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Georgi Djakov <djakov@kernel.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Vinod Koul <vkoul@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: Dmitry Osipenko <digetx@gmail.com> Cc: linux-iio@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: linux-mmc@vger.kernel.org Cc: linux-tegra@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-phy@lists.infradead.org Signed-off-by: Rob Herring <robh@kernel.org> Acked-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Acked-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20220330145741.3044896-1-robh@kernel.org