15 Jan, 2016

1 commit

  • Mark those kmem allocations that are known to be easily triggered from
    userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
    memcg. For the list, see below:

    - threadinfo
    - task_struct
    - task_delay_info
    - pid
    - cred
    - mm_struct
    - vm_area_struct and vm_region (nommu)
    - anon_vma and anon_vma_chain
    - signal_struct
    - sighand_struct
    - fs_struct
    - files_struct
    - fdtable and fdtable->full_fds_bits
    - dentry and external_name
    - inode for all filesystems. This is the most tedious part, because
    most filesystems overwrite the alloc_inode method.

    The list is far from complete, so feel free to add more objects.
    Nevertheless, it should be close to "account everything" approach and
    keep most workloads within bounds. Malevolent users will be able to
    breach the limit, but this was possible even with the former "account
    everything" approach (simply because it did not account everything in
    fact).

    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: Vladimir Davydov
    Acked-by: Johannes Weiner
    Acked-by: Michal Hocko
    Cc: Tejun Heo
    Cc: Greg Thelen
    Cc: Christoph Lameter
    Cc: Pekka Enberg
    Cc: David Rientjes
    Cc: Joonsoo Kim
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Vladimir Davydov
     

09 Dec, 2015

1 commit

  • kmap() in page_follow_link_light() needed to go - allowing to hold
    an arbitrary number of kmaps for long is a great way to deadlocking
    the system.

    new helper (inode_nohighmem(inode)) needs to be used for pagecache
    symlinks inodes; done for all in-tree cases. page_follow_link_light()
    instrumented to yell about anything missed.

    Signed-off-by: Al Viro

    Al Viro
     

07 Dec, 2015

1 commit

  • It was to needed for a couple of months in 2010, until UFS
    quota support got dropped. Since then it's equivalent to
    simple_setattr() (i.e. the default) for everything except the
    regular files. And dropping it there allows to convert all
    UFS symlinks to {page,simple}_symlink_inode_operations, getting
    rid of fs/ufs/symlink.c completely.

    Signed-off-by: Al Viro

    Al Viro
     

10 Sep, 2015

1 commit

  • Followup to the UFS series - with the way we clear the new blocks (via
    buffer cache, possibly on more than a page worth of file) we really
    should not insert a reference to new block into inode block tree until
    after we'd cleared it.

    Signed-off-by: Al Viro
    Signed-off-by: Linus Torvalds

    Al Viro
     

07 Jul, 2015

36 commits