linux-stable.git/mm, branch v5.10.76

mm, slub: fix incorrect memcg slab count for bulk free

2021-10-27T07:56:53+00:00

commit 3ddd60268c24bcac9d744404cc277e9dc52fe6b6 upstream.

kmem_cache_free_bulk() will call memcg_slab_free_hook() for all objects
when doing bulk free.  So we shouldn't call memcg_slab_free_hook() again
for bulk free to avoid incorrect memcg slab count.

Link: https://lkml.kernel.org/r/20210916123920.48704-6-linmiaohe@huawei.com
Fixes: d1b2cf6cb84a ("mm: memcg/slab: uncharge during kmem_cache_free_bulk()")
Signed-off-by: Miaohe Lin 
Reviewed-by: Vlastimil Babka 
Cc: Andrey Konovalov 
Cc: Andrey Ryabinin 
Cc: Bharata B Rao 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Faiyaz Mohammed 
Cc: Greg Kroah-Hartman 
Cc: Joonsoo Kim 
Cc: Kees Cook 
Cc: Pekka Enberg 
Cc: Roman Gushchin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm, slub: fix potential memoryleak in kmem_cache_open()

2021-10-27T07:56:53+00:00

commit 9037c57681d25e4dcc442d940d6dbe24dd31f461 upstream.

In error path, the random_seq of slub cache might be leaked.  Fix this
by using __kmem_cache_release() to release all the relevant resources.

Link: https://lkml.kernel.org/r/20210916123920.48704-4-linmiaohe@huawei.com
Fixes: 210e7a43fa90 ("mm: SLUB freelist randomization")
Signed-off-by: Miaohe Lin 
Reviewed-by: Vlastimil Babka 
Cc: Andrey Konovalov 
Cc: Andrey Ryabinin 
Cc: Bharata B Rao 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Faiyaz Mohammed 
Cc: Greg Kroah-Hartman 
Cc: Joonsoo Kim 
Cc: Kees Cook 
Cc: Pekka Enberg 
Cc: Roman Gushchin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm, slub: fix mismatch between reconstructed freelist depth and cnt

2021-10-27T07:56:53+00:00

commit 899447f669da76cc3605665e1a95ee877bc464cc upstream.

If object's reuse is delayed, it will be excluded from the reconstructed
freelist.  But we forgot to adjust the cnt accordingly.  So there will
be a mismatch between reconstructed freelist depth and cnt.  This will
lead to free_debug_processing() complaining about freelist count or a
incorrect slub inuse count.

Link: https://lkml.kernel.org/r/20210916123920.48704-3-linmiaohe@huawei.com
Fixes: c3895391df38 ("kasan, slub: fix handling of kasan_slab_free hook")
Signed-off-by: Miaohe Lin 
Reviewed-by: Vlastimil Babka 
Cc: Andrey Konovalov 
Cc: Andrey Ryabinin 
Cc: Bharata B Rao 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Faiyaz Mohammed 
Cc: Greg Kroah-Hartman 
Cc: Joonsoo Kim 
Cc: Kees Cook 
Cc: Pekka Enberg 
Cc: Roman Gushchin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm: don't allow oversized kvmalloc() calls

2021-10-06T13:56:03+00:00

commit 7661809d493b426e979f39ab512e3adf41fbcc69 upstream.

'kvmalloc()' is a convenience function for people who want to do a
kmalloc() but fall back on vmalloc() if there aren't enough physically
contiguous pages, or if the allocation is larger than what kmalloc()
supports.

However, let's make sure it doesn't get _too_ easy to do crazy things
with it.  In particular, don't allow big allocations that could be due
to integer overflow or underflow.  So make sure the allocation size fits
in an 'int', to protect against trivial integer conversion issues.

Acked-by: Willy Tarreau 
Cc: Kees Cook 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm: fix uninitialized use in overcommit_policy_handler

2021-09-30T08:10:58+00:00

commit bcbda81020c3ee77e2c098cadf3e84f99ca3de17 upstream.

We get an unexpected value of /proc/sys/vm/overcommit_memory after
running the following program:

  int main()
  {
      int fd = open("/proc/sys/vm/overcommit_memory", O_RDWR);
      write(fd, "1", 1);
      write(fd, "2", 1);
      close(fd);
  }

write(fd, "2", 1) will pass *ppos = 1 to proc_dointvec_minmax.
proc_dointvec_minmax will return 0 without setting new_policy.

  t.data = &new_policy;
  ret = proc_dointvec_minmax(&t, write, buffer, lenp, ppos)
      -->do_proc_dointvec
         -->__do_proc_dointvec
              if (write) {
                if (proc_first_pos_non_zero_ignore(ppos, table))
                  goto out;

  sysctl_overcommit_memory = new_policy;

so sysctl_overcommit_memory will be set to an uninitialized value.

Check whether new_policy has been changed by proc_dointvec_minmax.

Link: https://lkml.kernel.org/r/20210923020524.13289-1-chenjun102@huawei.com
Fixes: 56f3547bfa4d ("mm: adjust vm_committed_as_batch according to vm overcommit policy")
Signed-off-by: Chen Jun 
Acked-by: Michal Hocko 
Reviewed-by: Feng Tang 
Reviewed-by: Kefeng Wang 
Cc: Rui Xiang 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm/memory_hotplug: use "unsigned long" for PFN in zone_for_pfn_range()

2021-09-22T10:27:59+00:00

commit 7cf209ba8a86410939a24cb1aeb279479a7e0ca6 upstream.

Patch series "mm/memory_hotplug: preparatory patches for new online policy and memory"

These are all cleanups and one fix previously sent as part of [1]:
[PATCH v1 00/12] mm/memory_hotplug: "auto-movable" online policy and memory
groups.

These patches make sense even without the other series, therefore I pulled
them out to make the other series easier to digest.

[1] https://lkml.kernel.org/r/20210607195430.48228-1-david@redhat.com

This patch (of 4):

Checkpatch complained on a follow-up patch that we are using "unsigned"
here, which defaults to "unsigned int" and checkpatch is correct.

As we will search for a fitting zone using the wrong pfn, we might end
up onlining memory to one of the special kernel zones, such as ZONE_DMA,
which can end badly as the onlined memory does not satisfy properties of
these zones.

Use "unsigned long" instead, just as we do in other places when handling
PFNs.  This can bite us once we have physical addresses in the range of
multiple TB.

Link: https://lkml.kernel.org/r/20210712124052.26491-2-david@redhat.com
Fixes: e5e689302633 ("mm, memory_hotplug: display allowed zones in the preferred ordering")
Signed-off-by: David Hildenbrand 
Reviewed-by: Pankaj Gupta 
Reviewed-by: Muchun Song 
Reviewed-by: Oscar Salvador 
Cc: David Hildenbrand 
Cc: Vitaly Kuznetsov 
Cc: "Michael S. Tsirkin" 
Cc: Jason Wang 
Cc: Pankaj Gupta 
Cc: Wei Yang 
Cc: Michal Hocko 
Cc: Dan Williams 
Cc: Anshuman Khandual 
Cc: Dave Hansen 
Cc: Vlastimil Babka 
Cc: Mike Rapoport 
Cc: "Rafael J. Wysocki" 
Cc: Len Brown 
Cc: Pavel Tatashin 
Cc: Heiko Carstens 
Cc: Michael Ellerman 
Cc: Catalin Marinas 
Cc: virtualization@lists.linux-foundation.org
Cc: Andy Lutomirski 
Cc: "Aneesh Kumar K.V" 
Cc: Anton Blanchard 
Cc: Ard Biesheuvel 
Cc: Baoquan He 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Christian Borntraeger 
Cc: Christophe Leroy 
Cc: Dave Jiang 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Jia He 
Cc: Joe Perches 
Cc: Kefeng Wang 
Cc: Laurent Dufour 
Cc: Michel Lespinasse 
Cc: Nathan Lynch 
Cc: Nicholas Piggin 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Pierre Morel 
Cc: "Rafael J. Wysocki" 
Cc: Rich Felker 
Cc: Scott Cheloha 
Cc: Sergei Trofimovich 
Cc: Thiago Jung Bauermann 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vishal Verma 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: David Hildenbrand 
Signed-off-by: Greg Kroah-Hartman

mm,vmscan: fix divide by zero in get_scan_count

2021-09-18T11:40:36+00:00

commit 32d4f4b782bb8f0ceb78c6b5dc46eb577ae25bf7 upstream.

Commit f56ce412a59d ("mm: memcontrol: fix occasional OOMs due to
proportional memory.low reclaim") introduced a divide by zero corner
case when oomd is being used in combination with cgroup memory.low
protection.

When oomd decides to kill a cgroup, it will force the cgroup memory to
be reclaimed after killing the tasks, by writing to the memory.max file
for that cgroup, forcing the remaining page cache and reclaimable slab
to be reclaimed down to zero.

Previously, on cgroups with some memory.low protection that would result
in the memory being reclaimed down to the memory.low limit, or likely
not at all, having the page cache reclaimed asynchronously later.

With f56ce412a59d the oomd write to memory.max tries to reclaim all the
way down to zero, which may race with another reclaimer, to the point of
ending up with the divide by zero below.

This patch implements the obvious fix.

Link: https://lkml.kernel.org/r/20210826220149.058089c6@imladris.surriel.com
Fixes: f56ce412a59d ("mm: memcontrol: fix occasional OOMs due to proportional memory.low reclaim")
Signed-off-by: Rik van Riel 
Acked-by: Roman Gushchin 
Acked-by: Michal Hocko 
Acked-by: Johannes Weiner 
Acked-by: Chris Down 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm/hmm: bypass devmap pte when all pfn requested flags are fulfilled

2021-09-18T11:40:36+00:00

commit 4b42fb213678d2b6a9eeea92a9be200f23e49583 upstream.

Previously, we noticed the one rpma example was failed[1] since commit
36f30e486dce ("IB/core: Improve ODP to use hmm_range_fault()"), where it
will use ODP feature to do RDMA WRITE between fsdax files.

After digging into the code, we found hmm_vma_handle_pte() will still
return EFAULT even though all the its requesting flags has been
fulfilled.  That's because a DAX page will be marked as (_PAGE_SPECIAL |
PAGE_DEVMAP) by pte_mkdevmap().

Link: https://github.com/pmem/rpma/issues/1142 [1]
Link: https://lkml.kernel.org/r/20210830094232.203029-1-lizhijian@cn.fujitsu.com
Fixes: 405506274922 ("mm/hmm: add missing call to hmm_pte_need_fault in HMM_PFN_SPECIAL handling")
Signed-off-by: Li Zhijian 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Jason Gunthorpe 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

hugetlb: fix hugetlb cgroup refcounting during vma split

2021-09-18T11:40:36+00:00

commit 09a26e832705fdb7a9484495b71a05e0bbc65207 upstream.

Guillaume Morin reported hitting the following WARNING followed by GPF or
NULL pointer deference either in cgroups_destroy or in the kill_css path.:

    percpu ref (css_release) <= 0 (-1) after switching to atomic
    WARNING: CPU: 23 PID: 130 at lib/percpu-refcount.c:196 percpu_ref_switch_to_atomic_rcu+0x127/0x130
    CPU: 23 PID: 130 Comm: ksoftirqd/23 Kdump: loaded Tainted: G           O      5.10.60 #1
    RIP: 0010:percpu_ref_switch_to_atomic_rcu+0x127/0x130
    Call Trace:
       rcu_core+0x30f/0x530
       rcu_core_si+0xe/0x10
       __do_softirq+0x103/0x2a2
       run_ksoftirqd+0x2b/0x40
       smpboot_thread_fn+0x11a/0x170
       kthread+0x10a/0x140
       ret_from_fork+0x22/0x30

Upon further examination, it was discovered that the css structure was
associated with hugetlb reservations.

For private hugetlb mappings the vma points to a reserve map that
contains a pointer to the css.  At mmap time, reservations are set up
and a reference to the css is taken.  This reference is dropped in the
vma close operation; hugetlb_vm_op_close.  However, if a vma is split no
additional reference to the css is taken yet hugetlb_vm_op_close will be
called twice for the split vma resulting in an underflow.

Fix by taking another reference in hugetlb_vm_op_open.  Note that the
reference is only taken for the owner of the reserve map.  In the more
common fork case, the pointer to the reserve map is cleared for
non-owning vmas.

Link: https://lkml.kernel.org/r/20210830215015.155224-1-mike.kravetz@oracle.com
Fixes: e9fe92ae0cd2 ("hugetlb_cgroup: add reservation accounting for private mappings")
Signed-off-by: Mike Kravetz 
Reported-by: Guillaume Morin 
Suggested-by: Guillaume Morin 
Tested-by: Guillaume Morin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

mm/page_alloc: speed up the iteration of max_order

2021-09-12T06:58:26+00:00

commit 7ad69832f37e3cea8557db6df7c793905f1135e8 upstream.

When we free a page whose order is very close to MAX_ORDER and greater
than pageblock_order, it wastes some CPU cycles to increase max_order to
MAX_ORDER one by one and check the pageblock migratetype of that page
repeatedly especially when MAX_ORDER is much larger than pageblock_order.

We also should not be checking migratetype of buddy when "order ==
MAX_ORDER - 1" as the buddy pfn may be invalid, so adjust the condition.
With the new check, we don't need the max_order check anymore, so we
replace it.

Also adjust max_order initialization so that it's lower by one than
previously, which makes the code hopefully more clear.

Link: https://lkml.kernel.org/r/20201204155109.55451-1-songmuchun@bytedance.com
Fixes: d9dddbf55667 ("mm/page_alloc: prevent merging between isolated and other pageblocks")
Signed-off-by: Muchun Song 
Acked-by: Vlastimil Babka 
Reviewed-by: Oscar Salvador 
Reviewed-by: David Hildenbrand 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman