eec3636ad1
Commit05ea88608d("mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct") adds a new ->pagesize() function to hugetlb_vm_ops, intended to cover all hugetlbfs backed files. With System V shared memory model, if "huge page" is specified, the "shared memory" is backed by hugetlbfs files, but the mappings initiated via shmget/shmat have their original vm_ops overwritten with shm_vm_ops, so we need to add a ->pagesize function to shm_vm_ops. Otherwise, vma_kernel_pagesize() returns PAGE_SIZE given a hugetlbfs backed vma, result in below BUG: fs/hugetlbfs/inode.c 443 if (unlikely(page_mapped(page))) { 444 BUG_ON(truncate_op); resulting in hugetlbfs: oracle (4592): Using mlock ulimits for SHM_HUGETLB is deprecated ------------[ cut here ]------------ kernel BUG at fs/hugetlbfs/inode.c:444! Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4 ... CPU: 35 PID: 5583 Comm: oracle_5583_sbt Not tainted 4.14.35-1829.el7uek.x86_64 #2 RIP: 0010:remove_inode_hugepages+0x3db/0x3e2 .... Call Trace: hugetlbfs_evict_inode+0x1e/0x3e evict+0xdb/0x1af iput+0x1a2/0x1f7 dentry_unlink_inode+0xc6/0xf0 __dentry_kill+0xd8/0x18d dput+0x1b5/0x1ed __fput+0x18b/0x216 ____fput+0xe/0x10 task_work_run+0x90/0xa7 exit_to_usermode_loop+0xdd/0x116 do_syscall_64+0x187/0x1ae entry_SYSCALL_64_after_hwframe+0x150/0x0 [jane.chu@oracle.com: relocate comment] Link: http://lkml.kernel.org/r/20180731044831.26036-1-jane.chu@oracle.com Link: http://lkml.kernel.org/r/20180727211727.5020-1-jane.chu@oracle.com Fixes:05ea88608d("mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct") Signed-off-by: Jane Chu <jane.chu@oracle.com> Suggested-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.