Christophe Leroy 4cb592436d powerpc/mm: Don't report hugepage tables as memory leaks when using kmemleak
[ Upstream commit 803d690e68 ]

When a process allocates a hugepage, the following leak is
reported by kmemleak. This is a false positive which is
due to the pointer to the table being stored in the PGD
as physical memory address and not virtual memory pointer.

unreferenced object 0xc30f8200 (size 512):
  comm "mmap", pid 374, jiffies 4872494 (age 627.630s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<e32b68da>] huge_pte_alloc+0xdc/0x1f8
    [<9e0df1e1>] hugetlb_fault+0x560/0x8f8
    [<7938ec6c>] follow_hugetlb_page+0x14c/0x44c
    [<afbdb405>] __get_user_pages+0x1c4/0x3dc
    [<b8fd7cd9>] __mm_populate+0xac/0x140
    [<3215421e>] vm_mmap_pgoff+0xb4/0xb8
    [<c148db69>] ksys_mmap_pgoff+0xcc/0x1fc
    [<4fcd760f>] ret_from_syscall+0x0/0x38

See commit a984506c54 ("powerpc/mm: Don't report PUDs as
memory leaks when using kmemleak") for detailed explanation.

To fix that, this patch tells kmemleak to ignore the allocated
hugepage table.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:24:03 +01:00
2018-11-13 11:15:11 -08:00
2018-11-13 11:15:18 -08:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

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.
Description
No description provided
Readme 7.9 GiB
Languages
C 97.7%
Assembly 1.6%
Makefile 0.3%
Perl 0.1%