Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-22 20:22:09 +00:00
Code Issues Packages Projects Releases Wiki Activity
A mirror of the official Linux kernel repository just in case
1,170,681 Commits 7 Branches 862 Tags 6.4 GiB
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%
9eac40fc0c
Go to file
David Hildenbrand 9eac40fc0c selftests/mm: mkdirty: test behavior of (pte|pmd)_mkdirty on VMAs without write permissions 
Let's add some tests that trigger (pte|pmd)_mkdirty on VMAs without write
permissions.  If an architecture implementation is wrong, we might
accidentally set the PTE/PMD writable and allow for write access in a VMA
without write permissions.

The tests include reproducers for the two issues recently discovered
and worked-around in core-MM for now:

(1) commit 624a2c94f5 ("Partly revert "mm/thp: carry over dirty
    bit when thp splits on pmd"")
(2) commit 96a9c287e2 ("mm/migrate: fix wrongly apply write bit
    after mkdirty on sparc64")

In addition, some other tests that reveal further issues.

All tests pass under x86_64:
	./mkdirty
	# [INFO] detected THP size: 2048 KiB
	TAP version 13
	1..6
	# [INFO] PTRACE write access
	ok 1 SIGSEGV generated, page not modified
	# [INFO] PTRACE write access to THP
	ok 2 SIGSEGV generated, page not modified
	# [INFO] Page migration
	ok 3 SIGSEGV generated, page not modified
	# [INFO] Page migration of THP
	ok 4 SIGSEGV generated, page not modified
	# [INFO] PTE-mapping a THP
	ok 5 SIGSEGV generated, page not modified
	# [INFO] UFFDIO_COPY
	ok 6 SIGSEGV generated, page not modified
	# Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0

But some fail on sparc64:
	./mkdirty
	# [INFO] detected THP size: 8192 KiB
	TAP version 13
	1..6
	# [INFO] PTRACE write access
	not ok 1 SIGSEGV generated, page not modified
	# [INFO] PTRACE write access to THP
	not ok 2 SIGSEGV generated, page not modified
	# [INFO] Page migration
	ok 3 SIGSEGV generated, page not modified
	# [INFO] Page migration of THP
	ok 4 SIGSEGV generated, page not modified
	# [INFO] PTE-mapping a THP
	ok 5 SIGSEGV generated, page not modified
	# [INFO] UFFDIO_COPY
	not ok 6 SIGSEGV generated, page not modified
	Bail out! 3 out of 6 tests failed
	# Totals: pass:3 fail:3 xfail:0 xpass:0 skip:0 error:0

Reverting both above commits makes all tests fail on sparc64:
	./mkdirty
	# [INFO] detected THP size: 8192 KiB
	TAP version 13
	1..6
	# [INFO] PTRACE write access
	not ok 1 SIGSEGV generated, page not modified
	# [INFO] PTRACE write access to THP
	not ok 2 SIGSEGV generated, page not modified
	# [INFO] Page migration
	not ok 3 SIGSEGV generated, page not modified
	# [INFO] Page migration of THP
	not ok 4 SIGSEGV generated, page not modified
	# [INFO] PTE-mapping a THP
	not ok 5 SIGSEGV generated, page not modified
	# [INFO] UFFDIO_COPY
	not ok 6 SIGSEGV generated, page not modified
	Bail out! 6 out of 6 tests failed
	# Totals: pass:0 fail:6 xfail:0 xpass:0 skip:0 error:0

The tests are useful to detect other problematic archs, to verify new
arch fixes, and to stop such issues from reappearing in the future.

For now, we don't add any hugetlb tests.

Link: https://lkml.kernel.org/r/20230411142512.438404-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 16:30:00 -07:00
arch m68k/mm: use correct bit number in _PAGE_SWP_EXCLUSIVE comment 2023-04-18 16:29:53 -07:00
block block: remove obsolete config BLOCK_COMPAT 2023-03-16 09:35:44 -06:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto asymmetric_keys: log on fatal failures in PE/pkcs7 2023-03-21 16:23:56 +00:00
Documentation sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes 2023-04-16 12:31:58 -07:00
drivers zram: return errors from read_from_bdev_sync 2023-04-18 16:30:00 -07:00
fs smaps: fix defined but not used smaps_shmem_walk_ops 2023-04-18 16:29:54 -07:00
include userfaultfd: convert mfill_atomic() to use a folio 2023-04-18 16:29:55 -07:00
init init,mm: fold late call to page_ext_init() to page_alloc_init_late() 2023-04-05 19:42:54 -07:00
io_uring block-6.3-2023-03-24 2023-03-24 14:10:39 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel prctl: add PR_GET_AUXV to copy auxv to userspace 2023-04-18 16:29:53 -07:00
lib maple_tree: use correct variable type in sizeof 2023-04-18 16:29:56 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: backing-dev: set variables dev_attr_min,max_bytes storage-class-specifier to static 2023-04-18 16:29:56 -07:00
net mm, treewide: redefine MAX_ORDER sanely 2023-04-05 19:42:46 -07:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples kmemleak-test: fix kmemleak_test.c build logic 2023-04-18 16:29:47 -07:00
scripts kasan: remove hwasan-kernel-mem-intrinsic-prefix=1 for clang-14 2023-04-18 16:29:43 -07:00
security mm, treewide: redefine MAX_ORDER sanely 2023-04-05 19:42:46 -07:00
sound ALSA: hda/ca0132: fixup buffer overrun at tuning_ctl_set() 2023-03-14 17:04:53 +01:00
tools selftests/mm: mkdirty: test behavior of (pte|pmd)_mkdirty on VMAs without write permissions 2023-04-18 16:30:00 -07:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM/riscv changes for 6.3 2023-02-15 12:33:28 -05:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore kbuild: rpm-pkg: move source components to rpmbuild/SOURCES 2023-03-16 22:45:56 +09:00
.mailmap mailmap: update jtoppins' entry to reference correct email 2023-04-16 10:41:25 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: extend memblock entry to include MM initialization 2023-04-05 19:42:55 -07:00
Makefile Linux 6.3-rc4 2023-03-26 14:40:20 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

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.

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.