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Kirill A. Shutemov c8394812e5 uprobes: split THPs before trying to replace them
Patch series "Fix few rmap-related THP bugs", v3.

The patchset fixes handing PTE-mapped THPs in page_referenced() and
page_idle_clear_pte_refs().

To achieve that I've intrdocued new helper -- page_vma_mapped_walk() --
which replaces all page_check_address{,_transhuge}() and covers all THP
cases.

Patchset overview:
  - First patch fixes one uprobe bug (unrelated to the rest of the
    patchset, just spotted it at the same time);

  - Patches 2-5 fix handling PTE-mapped THPs in page_referenced(),
    page_idle_clear_pte_refs() and rmap core;

  - Patches 6-12 convert all page_check_address{,_transhuge}() users
    (plus remove_migration_pte()) to page_vma_mapped_walk() and drop
    unused helpers.

I think the fixes are not critical enough for stable@ as they don't lead
to crashes or hangs, only suboptimal behaviour.

This patch (of 12):

For THPs page_check_address() always fails.  It leads to endless loop in
uprobe_write_opcode().

Testcase with huge-tmpfs (uprobes cannot probe anonymous memory).

	mount -t debugfs none /sys/kernel/debug
	mount -t tmpfs -o huge=always none /mnt
	gcc -Wall -O2 -o /mnt/test -x c - <<EOF
	int main(void)
	{
		return 0;
	}
	/* Padding to map the code segment with huge pmd */
	asm (".zero 2097152");
	EOF
	echo 'p /mnt/test:0' > /sys/kernel/debug/tracing/uprobe_events
	echo 1 > /sys/kernel/debug/tracing/events/uprobes/enable
	/mnt/test

Let's split THPs before trying to replace.

Link: http://lkml.kernel.org/r/20170129173858.45174-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
arch mm: fix get_user_pages() vs device-dax pud mappings 2017-02-24 17:46:54 -08:00
block
certs
crypto
Documentation mm/ksm: improve deduplication of zero pages with colouring 2017-02-24 17:46:53 -08:00
drivers mm: replace FAULT_FLAG_SIZE with parameter to huge_fault 2017-02-24 17:46:54 -08:00
firmware
fs mm: replace FAULT_FLAG_SIZE with parameter to huge_fault 2017-02-24 17:46:54 -08:00
include mm/migration: make isolate_movable_page always defined 2017-02-24 17:46:55 -08:00
init
ipc mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
kernel uprobes: split THPs before trying to replace them 2017-02-24 17:46:55 -08:00
lib Less anger inducing pull request for 4.11 2017-02-23 18:58:18 -08:00
mm mm/hotplug: enable memory hotplug for non-lru movable pages 2017-02-24 17:46:55 -08:00
net
samples
scripts
security mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
sound mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
tools userfaultfd: non-cooperative: selftest: enable REMOVE event test for shmem 2017-02-24 17:46:54 -08:00
usr
virt mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Less anger inducing pull request for 4.11 2017-02-23 18:58:18 -08:00
Makefile
README

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,
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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.