- 25 May, 2022 11 commits
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Julia Lawall authored
Spelling mistake (triple letters) in comment. Detected with the help of Coccinelle. Link: https://lkml.kernel.org/r/20220521111145.81697-94-Julia.Lawall@inria.frSigned-off-by:
Julia Lawall <Julia.Lawall@inria.fr> Reviewed-by:
Muchun Song <songmuchun@bytedance.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org>
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Suren Baghdasaryan authored
Introduce process_mrelease syscall sanity tests which include tests which expect to fail: - process_mrelease with invalid pidfd and flags inputs - process_mrelease on a live process with no pending signals and valid process_mrelease usage which is expected to succeed. Because process_mrelease has to be used against a process with a pending SIGKILL, it's possible that the process exits before process_mrelease gets called. In such cases we retry the test with a victim that allocates twice more memory up to 1GB. This would require the victim process to spend more time during exit and process_mrelease has a better chance of catching the process before it exits and succeeding. On success the test reports the amount of memory the child had to allocate for reaping to succeed. Sample output: $ mrelease_test Success reaping a child with 1MB of memory allocations On failure the test reports the failure. Sample outputs: $ mrelease_test All process_mrelease attempts failed! $ mrelease_test process_mrelease: Invalid argument Link: https://lkml.kernel.org/r/20220518204316.13131-1-surenb@google.comSigned-off-by:
Suren Baghdasaryan <surenb@google.com> Reviewed-by:
Shuah Khan <skhan@linuxfoundation.org> Acked-by:
Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by:
Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <guro@fb.com> Cc: Minchan Kim <minchan@kernel.org> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Signed-off-by:
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Johannes Weiner authored
This reverts commit 3a235693. Its premise was that cgroup reclaim cares about freeing memory inside the cgroup, and demotion just moves them around within the cgroup limit. Hence, pages from toptier nodes should be reclaimed directly. However, with NUMA balancing now doing tier promotions, demotion is part of the page aging process. Global reclaim demotes the coldest toptier pages to secondary memory, where their life continues and from which they have a chance to get promoted back. Essentially, tiered memory systems have an LRU order that spans multiple nodes. When cgroup reclaims pages coming off the toptier directly, there can be colder pages on lower tier nodes that were demoted by global reclaim. This is an aging inversion, not unlike if cgroups were to reclaim directly from the active lists while there are inactive pages. Proactive reclaim is another factor. The goal of that it is to offload colder pages from expensive RAM to cheaper storage. When lower tier memory is available as an intermediate layer, we want offloading to take advantage of it instead of bypassing to storage. Revert the patch so that cgroups respect the LRU order spanning the memory hierarchy. Of note is a specific undercommit scenario, where all cgroup limits in the system add up to <= available toptier memory. In that case, shuffling pages out to lower tiers first to reclaim them from there is inefficient. This is something could be optimized/short-circuited later on (although care must be taken not to accidentally recreate the aging inversion). Let's ensure correctness first. Link: https://lkml.kernel.org/r/20220518190911.82400-1-hannes@cmpxchg.orgSigned-off-by:
Johannes Weiner <hannes@cmpxchg.org> Acked-by:
Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by:
Yang Shi <shy828301@gmail.com> Acked-by:
Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by:
"Huang, Ying" <ying.huang@intel.com> Reviewed-by:
Michal Hocko <mhocko@suse.com> Acked-by:
Shakeel Butt <shakeelb@google.com> Acked-by:
Tim Chen <tim.c.chen@linux.intel.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by:
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Jackie Liu authored
By printing information, we can friendly prompt the status change information of kfence by dmesg and record by syslog. Also, set kfence_enabled to false only when needed. Link: https://lkml.kernel.org/r/20220518073105.3160335-1-liu.yun@linux.devSigned-off-by:
Jackie Liu <liuyun01@kylinos.cn> Co-developed-by:
Marco Elver <elver@google.com> Signed-off-by:
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Vasily Averin authored
Fix sparse warning about incorrect gfp_t cast. Link: https://lkml.kernel.org/r/001979f3-e978-0998-cbed-61a4a2ac87b8@openvz.org Fixes: f67bed13 ("percpu: improve percpu_alloc_percpu event trace") Signed-off-by:
Vasily Averin <vvs@openvz.org> Signed-off-by:
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Vasily Averin authored
Redefines __def_gfpflag_names array according to akpm@, willy@ and Joe Perches recommendations. Link: https://lkml.kernel.org/r/6f811e19-41c6-f3e8-fca6-23a19a62e313@openvz.org Fixes: fe573327 ("tracing: incorrect gfp_t conversion") Signed-off-by:
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Zi Yan authored
In isolate_single_pageblock() called by start_isolate_page_range(), there are some pageblock isolation issues causing a potential infinite loop when isolating a page range. This is reported by Qian Cai. 1. the pageblock was isolated by just changing pageblock migratetype without checking unmovable pages. Calling set_migratetype_isolate() to isolate pageblock properly. 2. an off-by-one error caused migrating pages unnecessarily, since the page is not crossing pageblock boundary. 3. migrating a compound page across pageblock boundary then splitting the free page later has a small race window that the free page might be allocated again, so that the code will try again, causing an potential infinite loop. Temporarily set the to-be-migrated page's pageblock to MIGRATE_ISOLATE to prevent that and bail out early if no free page is found after page migration. An additional fix to split_free_page() aims to avoid crashing in __free_one_page(). When the free page is split at the specified split_pfn_offset, free_page_order should check both the first bit of free_page_pfn and the last bit of split_pfn_offset and use the smaller one. For example, if free_page_pfn=0x10000, split_pfn_offset=0xc000, free_page_order should first be 0x8000 then 0x4000, instead of 0x4000 then 0x8000, which the original algorithm did. [akpm@linux-foundation.org: suppress min() warning] Link: https://lkml.kernel.org/r/20220524194756.1698351-1-zi.yan@sent.com Fixes: b2c9e2fb ("mm: make alloc_contig_range work at pageblock granularity") Signed-off-by:
Zi Yan <ziy@nvidia.com> Reported-by:
Qian Cai <quic_qiancai@quicinc.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: David Hildenbrand <david@redhat.com> Cc: Eric Ren <renzhengeek@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by:
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Muchun Song authored
I have been focusing on mm for the past two years. e.g. developing, fixing bugs, reviewing related to HugeTLB system. I would like to help Mike and other people working on HugeTLB by reviewing their work. When I first introduced the vmemmmap reduction, I forgot to update MAINTAINERS file. Let's update it as well. And rename "HUGETLB FILESYSTEM" to "HUGETLB SUBSYSTEM" since some files are not only related to filesystem but also memory management (the name of FILESYSTEM cannot cover this area). Link: https://lkml.kernel.org/r/20220521074103.79468-1-songmuchun@bytedance.comSigned-off-by:
Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by:
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Randy Dunlap authored
ZSMALLOC depends on MMU so ZRAM should also depend on MMU since 'select' does not follow any dependency chains. Fixes this Kconfig warning: WARNING: unmet direct dependencies detected for ZSMALLOC Depends on [n]: MMU [=n] Selected by [y]: - ZRAM [=y] && BLK_DEV [=y] && BLOCK [=y] && SYSFS [=y] && (CRYPTO_LZO [=y] || CRYPTO_ZSTD [=m] || CRYPTO_LZ4 [=m] || CRYPTO_LZ4HC [=n] || CRYPTO_842 [=n]) Link: https://lkml.kernel.org/r/20220522204027.22964-1-rdunlap@infradead.org Fixes: b3fbd58f ("mm: Kconfig: simplify zswap configuration") Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Acked-by:
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Hugh Dickins authored
Shmem swapoff makes no progress: the index to indices is not incremented. But "ret" is no longer a return value, so use folio_batch_count() instead. Link: https://lkml.kernel.org/r/c32bee8a-f0aa-245-f94e-24dd271924fa@google.com Fixes: da08e9b7 ("mm/shmem: convert shmem_swapin_page() to shmem_swapin_folio()") Signed-off-by:
Hugh Dickins <hughd@google.com> Reviewed-by:
Miaohe Lin <linmiaohe@huawei.com> Tested-by:
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Christophe JAILLET authored
If the first goto is taken, 'fd' is not opened yet (and is un-initialized). So a direct return is safer. Link: https://lkml.kernel.org/r/628312312eb40e0e39463a2c06415fde5295c716.1653229120.git.christophe.jaillet@wanadoo.fr Fixes: c1a31a2f ("cgroup: fix racy check in alloc_pagecache_max_30M() helper function") Signed-off-by:
Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by:
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- 19 May, 2022 29 commits
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Kefeng Wang authored
Use HPAGE_PMD_SIZE instead of open coding. Link: https://lkml.kernel.org/r/20220517145120.118523-1-wangkefeng.wang@huawei.comSigned-off-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by:
SeongJae Park <sj@kernel.org> Signed-off-by:
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Vasily Averin authored
Fixes following sparse warnings: CHECK mm/vmscan.c mm/vmscan.c: note: in included file (through include/trace/trace_events.h, include/trace/define_trace.h, include/trace/events/vmscan.h): ./include/trace/events/vmscan.h:281:1: sparse: warning: cast to restricted isolate_mode_t ./include/trace/events/vmscan.h:281:1: sparse: warning: restricted isolate_mode_t degrades to integer Link: https://lkml.kernel.org/r/e85d7ff2-fd10-53f8-c24e-ba0458439c1b@openvz.orgSigned-off-by:
Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by:
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Christophe de Dinechin authored
With gcc version 12.0.1 20220401 (Red Hat 12.0.1-0), building with defconfig results in the following compilation error: | CC mm/swapfile.o | mm/swapfile.c: In function `setup_swap_info': | mm/swapfile.c:2291:47: error: array subscript -1 is below array bounds | of `struct plist_node[]' [-Werror=array-bounds] | 2291 | p->avail_lists[i].prio = 1; | | ~~~~~~~~~~~~~~^~~ | In file included from mm/swapfile.c:16: | ./include/linux/swap.h:292:27: note: while referencing `avail_lists' | 292 | struct plist_node avail_lists[]; /* | | ^~~~~~~~~~~ This is due to the compiler detecting that the mask in node_states[__state] could theoretically be zero, which would lead to first_node() returning -1 through find_first_bit. I believe that the warning/error is legitimate. I first tried adding a test to check that the node mask is not emtpy, since a similar test exists in the case where MAX_NUMNODES == 1. However, adding the if statement causes other warnings to appear in for_each_cpu_node_but, because it introduces a dangling else ambiguity. And unfortunately, GCC is not smart enough to detect that the added test makes the case where (node) == -1 impossible, so it still complains with the same message. This is why I settled on replacing that with a harmless, but relatively useless (node) >= 0 test. Based on the warning for the dangling else, I also decided to fix the case where MAX_NUMNODES == 1 by moving the condition inside the for loop. It will still only be tested once. This ensures that the meaning of an else following for_each_node_mask or derivatives would not silently have a different meaning depending on the configuration. Link: https://lkml.kernel.org/r/20220414150855.2407137-3-dinechin@redhat.comSigned-off-by:
Christophe de Dinechin <christophe@dinechin.org> Signed-off-by:
Christophe de Dinechin <dinechin@redhat.com> Reviewed-by:
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Qi Zheng authored
We expect no warnings to be issued when we specify __GFP_NOWARN, but currently in paths like alloc_pages() and kmalloc(), there are still some warnings printed, fix it. But for some warnings that report usage problems, we don't deal with them. If such warnings are printed, then we should fix the usage problems. Such as the following case: WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1)); [zhengqi.arch@bytedance.com: v2] Link: https://lkml.kernel.org/r/20220511061951.1114-1-zhengqi.arch@bytedance.com Link: https://lkml.kernel.org/r/20220510113809.80626-1-zhengqi.arch@bytedance.comSigned-off-by:
Qi Zheng <zhengqi.arch@bytedance.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jirislaby@kernel.org> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by:
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Wonhyuk Yang authored
Currently, trace point mm_page_alloc_zone_locked() doesn't show correct information. First, when alloc_flag has ALLOC_HARDER/ALLOC_CMA, page can be allocated from MIGRATE_HIGHATOMIC/MIGRATE_CMA. Nevertheless, tracepoint use requested migration type not MIGRATE_HIGHATOMIC and MIGRATE_CMA. Second, after commit 44042b44 ("mm/page_alloc: allow high-order pages to be stored on the per-cpu lists") percpu-list can store high order pages. But trace point determine whether it is a refiil of percpu-list by comparing requested order and 0. To handle these problems, make mm_page_alloc_zone_locked() only be called by __rmqueue_smallest with correct migration type. With a new argument called percpu_refill, it can show roughly whether it is a refill of percpu-list. Link: https://lkml.kernel.org/r/20220512025307.57924-1-vvghjk1234@gmail.comSigned-off-by:
Wonhyuk Yang <vvghjk1234@gmail.com> Acked-by:
Mel Gorman <mgorman@suse.de> Cc: Baik Song An <bsahn@etri.re.kr> Cc: Hong Yeon Kim <kimhy@etri.re.kr> Cc: Taeung Song <taeung@reallinux.co.kr> Cc: <linuxgeek@linuxgeek.io> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by:
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Fanjun Kong authored
This patch fixes two issues: 1. Add __initdata attribute according to include/linux/init.h: For initialized data: You should insert __initdata between the variable name and equal sign followed by value 2. Fix below error reported by checkpatch.pl: ERROR: do not initialise statics to false Special thanks to Muchun Song :) Link: https://lkml.kernel.org/r/20220516030039.1487005-1-bh1scw@gmail.comSigned-off-by:
Fanjun Kong <bh1scw@gmail.com> Suggested-by:
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Luo Meng authored
When shmem_reconfigure() calls __percpu_counter_compare(), the second parameter is unsigned long long. But in the definition of __percpu_counter_compare(), the second parameter is s64. So when __percpu_counter_compare() executes abs(count - rhs), UBSAN shows the following warning: ================================================================================ UBSAN: Undefined behaviour in lib/percpu_counter.c:209:6 signed integer overflow: 0 - -9223372036854775808 cannot be represented in type 'long long int' CPU: 1 PID: 9636 Comm: syz-executor.2 Tainted: G ---------r- - 4.18.0 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack home/install/linux-rh-3-10/lib/dump_stack.c:77 [inline] dump_stack+0x125/0x1ae home/install/linux-rh-3-10/lib/dump_stack.c:117 ubsan_epilogue+0xe/0x81 home/install/linux-rh-3-10/lib/ubsan.c:159 handle_overflow+0x19d/0x1ec home/install/linux-rh-3-10/lib/ubsan.c:190 __percpu_counter_compare+0x124/0x140 home/install/linux-rh-3-10/lib/percpu_counter.c:209 percpu_counter_compare home/install/linux-rh-3-10/./include/linux/percpu_counter.h:50 [inline] shmem_remount_fs+0x1ce/0x6b0 home/install/linux-rh-3-10/mm/shmem.c:3530 do_remount_sb+0x11b/0x530 home/install/linux-rh-3-10/fs/super.c:888 do_remount home/install/linux-rh-3-10/fs/namespace.c:2344 [inline] do_mount+0xf8d/0x26b0 home/install/linux-rh-3-10/fs/namespace.c:2844 ksys_mount+0xad/0x120 home/install/linux-rh-3-10/fs/namespace.c:3075 __do_sys_mount home/install/linux-rh-3-10/fs/namespace.c:3089 [inline] __se_sys_mount home/install/linux-rh-3-10/fs/namespace.c:3086 [inline] __x64_sys_mount+0xbf/0x160 home/install/linux-rh-3-10/fs/namespace.c:3086 do_syscall_64+0xca/0x5c0 home/install/linux-rh-3-10/arch/x86/entry/common.c:298 entry_SYSCALL_64_after_hwframe+0x6a/0xdf RIP: 0033:0x46b5e9 Code: 5d db fa ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b db fa ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f54d5f22c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000077bf60 RCX: 000000000046b5e9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 000000000077bf60 R08: 0000000020000140 R09: 0000000000000000 R10: 00000000026740a4 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd1fb1592f R14: 00007f54d5f239c0 R15: 000000000077bf6c ================================================================================ [akpm@linux-foundation.org: tweak error message text] Link: https://lkml.kernel.org/r/20220513025225.2678727-1-luomeng12@huawei.comSigned-off-by:
Luo Meng <luomeng12@huawei.com> Cc: Hugh Dickins <hughd@google.com> Cc: Yu Kuai <yukuai3@huawei.com> Signed-off-by:
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Wang Cheng authored
mpol_set_nodemask()(mm/mempolicy.c) does not set up nodemask when pol->mode is MPOL_LOCAL. Check pol->mode before access pol->w.cpuset_mems_allowed in mpol_rebind_policy()(mm/mempolicy.c). BUG: KMSAN: uninit-value in mpol_rebind_policy mm/mempolicy.c:352 [inline] BUG: KMSAN: uninit-value in mpol_rebind_task+0x2ac/0x2c0 mm/mempolicy.c:368 mpol_rebind_policy mm/mempolicy.c:352 [inline] mpol_rebind_task+0x2ac/0x2c0 mm/mempolicy.c:368 cpuset_change_task_nodemask kernel/cgroup/cpuset.c:1711 [inline] cpuset_attach+0x787/0x15e0 kernel/cgroup/cpuset.c:2278 cgroup_migrate_execute+0x1023/0x1d20 kernel/cgroup/cgroup.c:2515 cgroup_migrate kernel/cgroup/cgroup.c:2771 [inline] cgroup_attach_task+0x540/0x8b0 kernel/cgroup/cgroup.c:2804 __cgroup1_procs_write+0x5cc/0x7a0 kernel/cgroup/cgroup-v1.c:520 cgroup1_tasks_write+0x94/0xb0 kernel/cgroup/cgroup-v1.c:539 cgroup_file_write+0x4c2/0x9e0 kernel/cgroup/cgroup.c:3852 kernfs_fop_write_iter+0x66a/0x9f0 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2162 [inline] new_sync_write fs/read_write.c:503 [inline] vfs_write+0x1318/0x2030 fs/read_write.c:590 ksys_write+0x28b/0x510 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0xdb/0x120 fs/read_write.c:652 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:524 [inline] slab_alloc_node mm/slub.c:3251 [inline] slab_alloc mm/slub.c:3259 [inline] kmem_cache_alloc+0x902/0x11c0 mm/slub.c:3264 mpol_new mm/mempolicy.c:293 [inline] do_set_mempolicy+0x421/0xb70 mm/mempolicy.c:853 kernel_set_mempolicy mm/mempolicy.c:1504 [inline] __do_sys_set_mempolicy mm/mempolicy.c:1510 [inline] __se_sys_set_mempolicy+0x44c/0xb60 mm/mempolicy.c:1507 __x64_sys_set_mempolicy+0xd8/0x110 mm/mempolicy.c:1507 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x44/0xae KMSAN: uninit-value in mpol_rebind_task (2) https://syzkaller.appspot.com/bug?id=d6eb90f952c2a5de9ea718a1b873c55cb13b59dc This patch seems to fix below bug too. KMSAN: uninit-value in mpol_rebind_mm (2) https://syzkaller.appspot.com/bug?id=f2fecd0d7013f54ec4162f60743a2b28df40926b The uninit-value is pol->w.cpuset_mems_allowed in mpol_rebind_policy(). When syzkaller reproducer runs to the beginning of mpol_new(), mpol_new() mm/mempolicy.c do_mbind() mm/mempolicy.c kernel_mbind() mm/mempolicy.c `mode` is 1(MPOL_PREFERRED), nodes_empty(*nodes) is `true` and `flags` is 0. Then mode = MPOL_LOCAL; ... policy->mode = mode; policy->flags = flags; will be executed. So in mpol_set_nodemask(), mpol_set_nodemask() mm/mempolicy.c do_mbind() kernel_mbind() pol->mode is 4 (MPOL_LOCAL), that `nodemask` in `pol` is not initialized, which will be accessed in mpol_rebind_policy(). Link: https://lkml.kernel.org/r/20220512123428.fq3wofedp6oiotd4@ppc.localdomainSigned-off-by:
Wang Cheng <wanngchenng@gmail.com> Reported-by: <syzbot+217f792c92599518a2ab@syzkaller.appspotmail.com> Tested-by: <syzbot+217f792c92599518a2ab@syzkaller.appspotmail.com> Cc: David Rientjes <rientjes@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by:
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Minchan Kim authored
The rmap locks(i_mmap_rwsem and anon_vma->root->rwsem) could be contended under memory pressure if processes keep working on their vmas(e.g., fork, mmap, munmap). It makes reclaim path stuck. In our real workload traces, we see kswapd is waiting the lock for 300ms+(worst case, a sec) and it makes other processes entering direct reclaim, which were also stuck on the lock. This patch makes lru aging path try_lock mode like shink_page_list so the reclaim context will keep working with next lru pages without being stuck. if it found the rmap lock contended, it rotates the page back to head of lru in both active/inactive lrus to make them consistent behavior, which is basic starting point rather than adding more heristic. Since this patch introduces a new "contended" field as out-param along with try_lock in-param in rmap_walk_control, it's not immutable any longer if the try_lock is set so remove const keywords on rmap related functions. Since rmap walking is already expensive operation, I doubt the const would help sizable benefit( And we didn't have it until 5.17). In a heavy app workload in Android, trace shows following statistics. It almost removes rmap lock contention from reclaim path. Martin Liu reported: Before: max_dur(ms) min_dur(ms) max-min(dur)ms avg_dur(ms) sum_dur(ms) count blocked_function 1632 0 1631 151.542173 31672 209 page_lock_anon_vma_read 601 0 601 145.544681 28817 198 rmap_walk_file After: max_dur(ms) min_dur(ms) max-min(dur)ms avg_dur(ms) sum_dur(ms) count blocked_function NaN NaN NaN NaN NaN 0.0 NaN 0 0 0 0.127645 1 12 rmap_walk_file [minchan@kernel.org: add comment, per Matthew] Link: https://lkml.kernel.org/r/YnNqeB5tUf6LZ57b@google.com Link: https://lkml.kernel.org/r/20220510215423.164547-1-minchan@kernel.orgSigned-off-by:Minchan Kim <minchan@kernel.org> Acked-by:
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Johannes Weiner authored
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.orgSigned-off-by:
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Johannes Weiner authored
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.orgSigned-off-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:
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Johannes Weiner authored
- CONFIG_ZRAM: Zram is a user-facing feature, whereas zsmalloc is not. Don't make the user chase down a technical dependency like that, just select it in automatically when zram is requested. The CONFIG_CRYPTO dependency is redundant due to more specific deps. - CONFIG_ZPOOL: This is not a user-facing feature. Hide the symbol and have it selected in as needed. - CONFIG_ZSWAP: Select CRYPTO instead of depend. Common pattern. - Make the ZSWAP suboptions and their descriptions (compression, allocation backend) a bit more straight-forward for the user. Link: https://lkml.kernel.org/r/20220510152847.230957-5-hannes@cmpxchg.orgSigned-off-by:
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Johannes Weiner authored
There are several clusters of related config options spread throughout the mostly flat MM submenu. Group them together and put specialization options into further subdirectories to make the MM submenu a bit more organized and easier to navigate. [hannes@cmpxchg.org: fix kbuild warnings] Link: https://lkml.kernel.org/r/YnvkSVivfnT57Vwh@cmpxchg.org [hannes@cmpxchg.org: fix more kbuild warnings] Link: https://lkml.kernel.org/r/Ynz8NusTdEGcCnJN@cmpxchg.org Link: https://lkml.kernel.org/r/20220510152847.230957-4-hannes@cmpxchg.orgSigned-off-by:
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Johannes Weiner authored
These are currently under General Setup. MM seems like a better fit. Link: https://lkml.kernel.org/r/20220510152847.230957-3-hannes@cmpxchg.orgSigned-off-by:
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Johannes Weiner authored
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.orgSigned-off-by:
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Miaohe Lin authored
Since commit 4efaceb1 ("mm, swap: use rbtree for swap_extent"), rbtree is used for swap extent. Also curr_swap_extent is removed at that time. Update the corresponding comment. Link: https://lkml.kernel.org/r/20220509131416.17553-16-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
If no pages were pinned, 0 is returned in fact. Fix the corresponding comment. [akpm@linux-foundation.org: s/nr_pages/nr_segs/ also, per David, reflow comment] Link: https://lkml.kernel.org/r/20220509131416.17553-15-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Since commit 10a9c496 ("mm: simplify try_to_unuse"), frontswap parameter is removed. Update the corresponding comment. Link: https://lkml.kernel.org/r/20220509131416.17553-14-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Since commit 3159f943 ("xarray: Replace exceptional entries"), there is only one bit of 'type' can be shifted up. Update the corresponding comment. Link: https://lkml.kernel.org/r/20220509131416.17553-13-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Add helper swap_offset_available() to remove some duplicated codes. Minor readability improvement. [akpm@linux-foundation.org: s/swap_offset_available/swap_offset_available_and_locked/, per Neil] Link: https://lkml.kernel.org/r/20220509131416.17553-12-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Use flags of si directly to check SWP_STABLE_WRITES to avoid possible READ_ONCE and thus save some cpu cycles. [akpm@linux-foundation.org: use data_race() on si->flags, per Neil] Link: https://lkml.kernel.org/r/20220509131416.17553-10-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Make page_swapcount and __lru_add_drain_all static. They are only used within the file now. Link: https://lkml.kernel.org/r/20220509131416.17553-9-linmiaohe@huawei.comSigned-off-by:
Oscar Salvador <osalvador@suse.de> Cc: Alistair Popple <apopple@nvidia.com> Cc: David Howells <dhowells@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: NeilBrown <neilb@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by:
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Miaohe Lin authored
If p is NULL, __swap_duplicate will already return -EINVAL. So if we reach here, p must be non-NULL. Link: https://lkml.kernel.org/r/20220509131416.17553-8-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
refill_swap_slots_cache is always called when cache->nr is 0. So remove such buggy and confusing check. Link: https://lkml.kernel.org/r/20220509131416.17553-7-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
If offset exceeds the si->max, print bad swap offset entry to help debug the unexpected case. Link: https://lkml.kernel.org/r/20220509131416.17553-6-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
The return value of free_swap_slot is always 0 and also ignored now. Remove it to clean up the code. Link: https://lkml.kernel.org/r/20220509131416.17553-5-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Fold __swap_info_get() into its sole caller to make code more clear. Minor readability improvement. Link: https://lkml.kernel.org/r/20220509131416.17553-4-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Use helper macro __ATTR_RW to define vma_ra_enabled_attr to make code more clear. Minor readability improvement. Link: https://lkml.kernel.org/r/20220509131416.17553-3-linmiaohe@huawei.comSigned-off-by:
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Miaohe Lin authored
Patch series "A few cleanup patches for swap". This series contains a few patches to fix the comment, remove unneeded return value, use some helpers and so on. More details can be found in the respective changelogs. This patch (of 14): Use helper is_swap_pte() to check whether pte is swap entry to make code more clear. Minor readability improvement. Link: https://lkml.kernel.org/r/20220509131416.17553-1-linmiaohe@huawei.com Link: https://lkml.kernel.org/r/20220509131416.17553-2-linmiaohe@huawei.comSigned-off-by:
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