01 Oct, 2020
2 commits
-
[ Upstream commit 76518d3798855242817e8a8ed76b2d72f4415624 ]
This changes do_io_accounting to use the new exec_update_mutex
instead of cred_guard_mutex.This fixes possible deadlocks when the trace is accessing
/proc/$pid/io for instance.This should be safe, as the credentials are only used for reading.
Signed-off-by: Bernd Edlinger
Signed-off-by: Eric W. Biederman
Signed-off-by: Sasha Levin -
[ Upstream commit 2db9dbf71bf98d02a0bf33e798e5bfd2a9944696 ]
This changes lock_trace to use the new exec_update_mutex
instead of cred_guard_mutex.This fixes possible deadlocks when the trace is accessing
/proc/$pid/stack for instance.This should be safe, as the credentials are only used for reading,
and task->mm is updated on execve under the new exec_update_mutex.Signed-off-by: Bernd Edlinger
Signed-off-by: Eric W. Biederman
Signed-off-by: Sasha Levin
17 Jun, 2020
1 commit
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commit ef1548adada51a2f32ed7faef50aa465e1b4c5da upstream.
Recently syzbot reported that unmounting proc when there is an ongoing
inotify watch on the root directory of proc could result in a use
after free when the watch is removed after the unmount of proc
when the watcher exits.Commit 69879c01a0c3 ("proc: Remove the now unnecessary internal mount
of proc") made it easier to unmount proc and allowed syzbot to see the
problem, but looking at the code it has been around for a long time.Looking at the code the fsnotify watch should have been removed by
fsnotify_sb_delete in generic_shutdown_super. Unfortunately the inode
was allocated with new_inode_pseudo instead of new_inode so the inode
was not on the sb->s_inodes list. Which prevented
fsnotify_unmount_inodes from finding the inode and removing the watch
as well as made it so the "VFS: Busy inodes after unmount" warning
could not find the inodes to warn about them.Make all of the inodes in proc visible to generic_shutdown_super,
and fsnotify_sb_delete by using new_inode instead of new_inode_pseudo.
The only functional difference is that new_inode places the inodes
on the sb->s_inodes list.I wrote a small test program and I can verify that without changes it
can trigger this issue, and by replacing new_inode_pseudo with
new_inode the issues goes away.Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/000000000000d788c905a7dfa3f4@google.com
Reported-by: syzbot+7d2debdcdb3cb93c1e5e@syzkaller.appspotmail.com
Fixes: 0097875bd415 ("proc: Implement /proc/thread-self to point at the directory of the current thread")
Fixes: 021ada7dff22 ("procfs: switch /proc/self away from proc_dir_entry")
Fixes: 51f0885e5415 ("vfs,proc: guarantee unique inodes in /proc")
Signed-off-by: "Eric W. Biederman"
Signed-off-by: Greg Kroah-Hartman
29 Apr, 2020
1 commit
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commit bdebd6a2831b6fab69eb85cee74a8ba77f1a1cc2 upstream.
remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:- not detecting pgoff<<<<
Signed-off-by: Andrew Morton
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov
Cc: Daniel Borkmann
Cc: Martin KaFai Lau
Cc: Song Liu
Cc: Yonghong Song
Cc: Andrii Nakryiko
Cc: John Fastabend
Cc: KP Singh
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds
Signed-off-by: Greg Kroah-Hartman
19 Oct, 2019
2 commits
-
Patch series "Fixes for THP in page cache", v2.
This patch (of 5):
Add extra space for FileHugePages and FilePmdMapped, so the output is
aligned with other rows.Link: http://lkml.kernel.org/r/20191017164223.2762148-2-songliubraving@fb.com
Fixes: 60fbf0ab5da1 ("mm,thp: stats for file backed THP")
Signed-off-by: Kirill A. Shutemov
Signed-off-by: Song Liu
Tested-by: Song Liu
Acked-by: Yang Shi
Cc: Matthew Wilcox
Cc: Oleg Nesterov
Cc: Srikar Dronamraju
Cc: William Kucharski
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There are three places where we access uninitialized memmaps, namely:
- /proc/kpagecount
- /proc/kpageflags
- /proc/kpagecgroupWe have initialized memmaps either when the section is online or when the
page was initialized to the ZONE_DEVICE. Uninitialized memmaps contain
garbage and in the worst case trigger kernel BUGs, especially with
CONFIG_PAGE_POISONING.For example, not onlining a DIMM during boot and calling /proc/kpagecount
with CONFIG_PAGE_POISONING::/# cat /proc/kpagecount > tmp.test
BUG: unable to handle page fault for address: fffffffffffffffe
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 114616067 P4D 114616067 PUD 114618067 PMD 0
Oops: 0000 [#1] SMP NOPTI
CPU: 0 PID: 469 Comm: cat Not tainted 5.4.0-rc1-next-20191004+ #11
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.4
RIP: 0010:kpagecount_read+0xce/0x1e0
Code: e8 09 83 e0 3f 48 0f a3 02 73 2d 4c 89 e7 48 c1 e7 06 48 03 3d ab 51 01 01 74 1d 48 8b 57 08 480
RSP: 0018:ffffa14e409b7e78 EFLAGS: 00010202
RAX: fffffffffffffffe RBX: 0000000000020000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 00007f76b5595000 RDI: fffff35645000000
RBP: 00007f76b5595000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000140000
R13: 0000000000020000 R14: 00007f76b5595000 R15: ffffa14e409b7f08
FS: 00007f76b577d580(0000) GS:ffff8f41bd400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffffe CR3: 0000000078960000 CR4: 00000000000006f0
Call Trace:
proc_reg_read+0x3c/0x60
vfs_read+0xc5/0x180
ksys_read+0x68/0xe0
do_syscall_64+0x5c/0xa0
entry_SYSCALL_64_after_hwframe+0x49/0xbeFor now, let's drop support for ZONE_DEVICE from the three pseudo files
in order to fix this. To distinguish offline memory (with garbage
memmap) from ZONE_DEVICE memory with properly initialized memmaps, we
would have to check get_dev_pagemap() and pfn_zone_device_reserved()
right now. The usage of both (especially, special casing devmem) is
frowned upon and needs to be reworked.The fundamental issue we have is:
if (pfn_to_online_page(pfn)) {
/* memmap initialized */
} else if (pfn_valid(pfn)) {
/*
* ???
* a) offline memory. memmap garbage.
* b) devmem: memmap initialized to ZONE_DEVICE.
* c) devmem: reserved for driver. memmap garbage.
* (d) devmem: memmap currently initializing - garbage)
*/
}We'll leave the pfn_zone_device_reserved() check in stable_page_flags()
in place as that function is also used from memory failure. We now no
longer dump information about pages that are not in use anymore -
offline.Link: http://lkml.kernel.org/r/20191009142435.3975-2-david@redhat.com
Fixes: f1dd2cd13c4b ("mm, memory_hotplug: do not associate hotadded memory to zones until online") [visible after d0dc12e86b319]
Signed-off-by: David Hildenbrand
Reported-by: Qian Cai
Acked-by: Michal Hocko
Cc: Dan Williams
Cc: Alexey Dobriyan
Cc: Stephen Rothwell
Cc: Toshiki Fukasawa
Cc: Pankaj gupta
Cc: Mike Rapoport
Cc: Anthony Yznaga
Cc: "Aneesh Kumar K.V"
Cc: [4.13+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
28 Sep, 2019
1 commit
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Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
25 Sep, 2019
3 commits
-
In preparation for non-shmem THP, this patch adds a few stats and exposes
them in /proc/meminfo, /sys/bus/node/devices//meminfo, and
/proc//task//smaps.This patch is mostly a rewrite of Kirill A. Shutemov's earlier version:
https://lkml.kernel.org/r/20170126115819.58875-5-kirill.shutemov@linux.intel.com/Link: http://lkml.kernel.org/r/20190801184244.3169074-5-songliubraving@fb.com
Signed-off-by: Song Liu
Acked-by: Rik van Riel
Acked-by: Kirill A. Shutemov
Acked-by: Johannes Weiner
Cc: Hillf Danton
Cc: Hugh Dickins
Cc: William Kucharski
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Patch series "mm: remove quicklist page table caches".
A while ago Nicholas proposed to remove quicklist page table caches [1].
I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com
This patch (of 3):
Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.Also it might be better to instead make more general improvements to page
allocator if this is still so slow.Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin
Signed-off-by: Mike Rapoport
Cc: Tony Luck
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Replace 1 << compound_order(page) with compound_nr(page). Minor
improvements in readability.Link: http://lkml.kernel.org/r/20190721104612.19120-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle)
Reviewed-by: Andrew Morton
Reviewed-by: Ira Weiny
Acked-by: Kirill A. Shutemov
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Sep, 2019
1 commit
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Pull hmm updates from Jason Gunthorpe:
"This is more cleanup and consolidation of the hmm APIs and the very
strongly related mmu_notifier interfaces. Many places across the tree
using these interfaces are touched in the process. Beyond that a
cleanup to the page walker API and a few memremap related changes
round out the series:- General improvement of hmm_range_fault() and related APIs, more
documentation, bug fixes from testing, API simplification &
consolidation, and unused API removal- Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE,
and make them internal kconfig selects- Hoist a lot of code related to mmu notifier attachment out of
drivers by using a refcount get/put attachment idiom and remove the
convoluted mmu_notifier_unregister_no_release() and related APIs.- General API improvement for the migrate_vma API and revision of its
only user in nouveau- Annotate mmu_notifiers with lockdep and sleeping region debugging
Two series unrelated to HMM or mmu_notifiers came along due to
dependencies:- Allow pagemap's memremap_pages family of APIs to work without
providing a struct device- Make walk_page_range() and related use a constant structure for
function pointers"* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (75 commits)
libnvdimm: Enable unit test infrastructure compile checks
mm, notifier: Catch sleeping/blocking for !blockable
kernel.h: Add non_block_start/end()
drm/radeon: guard against calling an unpaired radeon_mn_unregister()
csky: add missing brackets in a macro for tlb.h
pagewalk: use lockdep_assert_held for locking validation
pagewalk: separate function pointers from iterator data
mm: split out a new pagewalk.h header from mm.h
mm/mmu_notifiers: annotate with might_sleep()
mm/mmu_notifiers: prime lockdep
mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end
mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exports
mm/hmm: hmm_range_fault() infinite loop
mm/hmm: hmm_range_fault() NULL pointer bug
mm/hmm: fix hmm_range_fault()'s handling of swapped out pages
mm/mmu_notifiers: remove unregister_no_release
RDMA/odp: remove ib_ucontext from ib_umem
RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm'
RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr
RDMA/mlx5: Use ib_umem_start instead of umem.address
...
21 Sep, 2019
1 commit
-
Pull powerpc updates from Michael Ellerman:
"This is a bit late, partly due to me travelling, and partly due to a
power outage knocking out some of my test systems *while* I was
travelling.- Initial support for running on a system with an Ultravisor, which
is software that runs below the hypervisor and protects guests
against some attacks by the hypervisor.- Support for building the kernel to run as a "Secure Virtual
Machine", ie. as a guest capable of running on a system with an
Ultravisor.- Some changes to our DMA code on bare metal, to allow devices with
medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of
DMA space.- Support for firmware assisted crash dumps on bare metal (powernv).
- Two series fixing bugs in and refactoring our PCI EEH code.
- A large series refactoring our exception entry code to use gas
macros, both to make it more readable and also enable some future
optimisations.As well as many cleanups and other minor features & fixups.
Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew
Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual,
Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe
JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig,
Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand,
Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg
Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim
Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo
Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan
Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver
O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm,
Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu,
Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom
Lendacky, Vasant Hegde"* tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits)
powerpc/mm/mce: Keep irqs disabled during lockless page table walk
powerpc: Use ftrace_graph_ret_addr() when unwinding
powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
ftrace: Look up the address of return_to_handler() using helpers
powerpc: dump kernel log before carrying out fadump or kdump
docs: powerpc: Add missing documentation reference
powerpc/xmon: Fix output of XIVE IPI
powerpc/xmon: Improve output of XIVE interrupts
powerpc/mm/radix: remove useless kernel messages
powerpc/fadump: support holes in kernel boot memory area
powerpc/fadump: remove RMA_START and RMA_END macros
powerpc/fadump: update documentation about option to release opalcore
powerpc/fadump: consider f/w load area
powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file
powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes
powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP
powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
powerpc/fadump: improve how crashed kernel's memory is reserved
powerpc/fadump: consider reserved ranges while releasing memory
powerpc/fadump: make crash memory ranges array allocation generic
...
07 Sep, 2019
2 commits
-
The mm_walk structure currently mixed data and code. Split out the
operations vectors into a new mm_walk_ops structure, and while we are
changing the API also declare the mm_walk structure inside the
walk_page_range and walk_page_vma functions.Based on patch from Linus Torvalds.
Link: https://lore.kernel.org/r/20190828141955.22210-3-hch@lst.de
Signed-off-by: Christoph Hellwig
Reviewed-by: Thomas Hellstrom
Reviewed-by: Steven Price
Reviewed-by: Jason Gunthorpe
Signed-off-by: Jason Gunthorpe -
Add a new header for the two handful of users of the walk_page_range /
walk_page_vma interface instead of polluting all users of mm.h with it.Link: https://lore.kernel.org/r/20190828141955.22210-2-hch@lst.de
Signed-off-by: Christoph Hellwig
Reviewed-by: Thomas Hellstrom
Reviewed-by: Steven Price
Reviewed-by: Jason Gunthorpe
Signed-off-by: Jason Gunthorpe
06 Sep, 2019
1 commit
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For vfs_get_keyed_super users.
Signed-off-by: Al Viro
20 Aug, 2019
2 commits
-
Print the content of current->comm in messages generated by lockdown to
indicate a restriction that was hit. This makes it a bit easier to find
out what caused the message.The message now patterned something like:
Lockdown: : is restricted; see man kernel_lockdown.7
Signed-off-by: David Howells
Signed-off-by: Matthew Garrett
Reviewed-by: Kees Cook
Signed-off-by: James Morris -
Disallow access to /proc/kcore when the kernel is locked down to prevent
access to cryptographic data. This is limited to lockdown
confidentiality mode and is still permitted in integrity mode.Signed-off-by: David Howells
Signed-off-by: Matthew Garrett
Reviewed-by: Kees Cook
Signed-off-by: James Morris
09 Aug, 2019
1 commit
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Secure Encrypted Virtualization is an x86-specific feature, so it shouldn't
appear in generic kernel code because it forces non-x86 architectures to
define the sev_active() function, which doesn't make a lot of sense.To solve this problem, add an x86 elfcorehdr_read() function to override
the generic weak implementation. To do that, it's necessary to make
read_from_oldmem() public so that it can be used outside of vmcore.c.Also, remove the export for sev_active() since it's only used in files that
won't be built as modules.Signed-off-by: Thiago Jung Bauermann
Reviewed-by: Christoph Hellwig
Reviewed-by: Lianbo Jiang
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20190806044919.10622-6-bauerman@linux.ibm.com
20 Jul, 2019
1 commit
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Pull vfs mount updates from Al Viro:
"The first part of mount updates.Convert filesystems to use the new mount API"
* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
mnt_init(): call shmem_init() unconditionally
constify ksys_mount() string arguments
don't bother with registering rootfs
init_rootfs(): don't bother with init_ramfs_fs()
vfs: Convert smackfs to use the new mount API
vfs: Convert selinuxfs to use the new mount API
vfs: Convert securityfs to use the new mount API
vfs: Convert apparmorfs to use the new mount API
vfs: Convert openpromfs to use the new mount API
vfs: Convert xenfs to use the new mount API
vfs: Convert gadgetfs to use the new mount API
vfs: Convert oprofilefs to use the new mount API
vfs: Convert ibmasmfs to use the new mount API
vfs: Convert qib_fs/ipathfs to use the new mount API
vfs: Convert efivarfs to use the new mount API
vfs: Convert configfs to use the new mount API
vfs: Convert binfmt_misc to use the new mount API
convenience helper: get_tree_single()
convenience helper get_tree_nodev()
vfs: Kill sget_userns()
...
19 Jul, 2019
2 commits
-
In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range. This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:$ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
248Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:# scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
Data old new delta
sysctl_vals - 12 +12
__kstrtab_sysctl_vals - 12 +12
max 14 10 -4
int_max 16 - -16
one 68 - -68
zero 128 28 -100
Total: Before=20583249, After=20583085, chg -0.00%[mcroce@redhat.com: tipc: remove two unused variables]
Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com
Signed-off-by: Matteo Croce
Signed-off-by: Arnd Bergmann
Acked-by: Kees Cook
Reviewed-by: Aaron Tomlin
Cc: Matthew Wilcox
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit 7635d9cbe832 ("mm, thp, proc: report THP eligibility for each
vma") introduced THPeligible bit for processes' smaps. But, when
checking the eligibility for shmem vma, __transparent_hugepage_enabled()
is called to override the result from shmem_huge_enabled(). It may
result in the anonymous vma's THP flag override shmem's. For example,
running a simple test which create THP for shmem, but with anonymous THP
disabled, when reading the process's smaps, it may show:7fc92ec00000-7fc92f000000 rw-s 00000000 00:14 27764 /dev/shm/test
Size: 4096 kB
...
[snip]
...
ShmemPmdMapped: 4096 kB
...
[snip]
...
THPeligible: 0And, /proc/meminfo does show THP allocated and PMD mapped too:
ShmemHugePages: 4096 kB
ShmemPmdMapped: 4096 kBThis doesn't make too much sense. The shmem objects should be treated
separately from anonymous THP. Calling shmem_huge_enabled() with
checking MMF_DISABLE_THP sounds good enough. And, we could skip stack
and dax vma check since we already checked if the vma is shmem already.Also check if vma is suitable for THP by calling
transhuge_vma_suitable().And minor fix to smaps output format and documentation.
Link: http://lkml.kernel.org/r/1560401041-32207-3-git-send-email-yang.shi@linux.alibaba.com
Fixes: 7635d9cbe832 ("mm, thp, proc: report THP eligibility for each vma")
Signed-off-by: Yang Shi
Acked-by: Hugh Dickins
Cc: Kirill A. Shutemov
Cc: Michal Hocko
Cc: Vlastimil Babka
Cc: David Rientjes
Cc: Andrea Arcangeli
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Jul, 2019
8 commits
-
Merge more updates from Andrew Morton:
"VM:
- z3fold fixes and enhancements by Henry Burns and Vitaly Wool- more accurate reclaimed slab caches calculations by Yafang Shao
- fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by
Christoph Hellwig- !CONFIG_MMU fixes by Christoph Hellwig
- new novmcoredd parameter to omit device dumps from vmcore, by
Kairui Song- new test_meminit module for testing heap and pagealloc
initialization, by Alexander Potapenko- ioremap improvements for huge mappings, by Anshuman Khandual
- generalize kprobe page fault handling, by Anshuman Khandual
- device-dax hotplug fixes and improvements, by Pavel Tatashin
- enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V
- add pte_devmap() support for arm64, by Robin Murphy
- unify locked_vm accounting with a helper, by Daniel Jordan
- several misc fixes
core/lib:
- new typeof_member() macro including some users, by Alexey Dobriyan- make BIT() and GENMASK() available in asm, by Masahiro Yamada
- changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better
code generation, by Alexey Dobriyan- rbtree code size optimizations, by Michel Lespinasse
- convert struct pid count to refcount_t, by Joel Fernandes
get_maintainer.pl:
- add --no-moderated switch to skip moderated ML's, by Joe Perchesmisc:
- ptrace PTRACE_GET_SYSCALL_INFO interface- coda updates
- gdb scripts, various"
[ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ]
* emailed patches from Andrew Morton : (100 commits)
fs/select.c: use struct_size() in kmalloc()
mm: add account_locked_vm utility function
arm64: mm: implement pte_devmap support
mm: introduce ARCH_HAS_PTE_DEVMAP
mm: clean up is_device_*_page() definitions
mm/mmap: move common defines to mman-common.h
mm: move MAP_SYNC to asm-generic/mman-common.h
device-dax: "Hotremove" persistent memory that is used like normal RAM
mm/hotplug: make remove_memory() interface usable
device-dax: fix memory and resource leak if hotplug fails
include/linux/lz4.h: fix spelling and copy-paste errors in documentation
ipc/mqueue.c: only perform resource calculation if user valid
include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures
scripts/gdb: add helpers to find and list devices
scripts/gdb: add lx-genpd-summary command
drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
kernel/pid.c: convert struct pid count to refcount_t
drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining()
select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR
... -
Normally, the inode's i_uid/i_gid are translated relative to s_user_ns,
but this is not a correct behavior for proc. Since sysctl permission
check in test_perm is done against GLOBAL_ROOT_[UG]ID, it makes more
sense to use these values in u_[ug]id of proc inodes. In other words:
although uid/gid in the inode is not read during test_perm, the inode
logically belongs to the root of the namespace. I have confirmed this
with Eric Biederman at LPC and in this thread:
https://lore.kernel.org/lkml/87k1kzjdff.fsf@xmission.comConsequences
============Since the i_[ug]id values of proc nodes are not used for permissions
checks, this change usually makes no functional difference. However, it
causes an issue in a setup where:* a namespace container is created without root user in container -
hence the i_[ug]id of proc nodes are set to INVALID_[UG]ID* container creator tries to configure it by writing /proc/sys files,
e.g. writing /proc/sys/kernel/shmmax to configure shared memory limitKernel does not allow to open an inode for writing if its i_[ug]id are
invalid, making it impossible to write shmmax and thus - configure the
container.Using a container with no root mapping is apparently rare, but we do use
this configuration at Google. Also, we use a generic tool to configure
the container limits, and the inability to write any of them causes a
failure.History
=======The invalid uids/gids in inodes first appeared due to 81754357770e (fs:
Update i_[ug]id_(read|write) to translate relative to s_user_ns).
However, AFAIK, this did not immediately cause any issues. The
inability to write to these "invalid" inodes was only caused by a later
commit 0bd23d09b874 (vfs: Don't modify inodes with a uid or gid unknown
to the vfs).Tested: Used a repro program that creates a user namespace without any
mapping and stat'ed /proc/$PID/root/proc/sys/kernel/shmmax from outside.
Before the change, it shows the overflow uid, with the change it's 0.
The overflow uid indicates that the uid in the inode is not correct and
thus it is not possible to open the file for writing.Link: http://lkml.kernel.org/r/20190708115130.250149-1-rburny@google.com
Fixes: 0bd23d09b874 ("vfs: Don't modify inodes with a uid or gid unknown to the vfs")
Signed-off-by: Radoslaw Burny
Acked-by: Luis Chamberlain
Cc: Kees Cook
Cc: "Eric W . Biederman"
Cc: Seth Forshee
Cc: John Sperbeck
Cc: Alexey Dobriyan
Cc: [4.8+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Don't repeat function signatures twice.
This is a kind-of-precursor for "struct proc_ops".
Note:
typeof(pde->proc_fops->...) ...;
can't be used because ->proc_fops is "const struct file_operations *".
"const" prevents assignment down the code and it can't be deleted in the
type system.Link: http://lkml.kernel.org/r/20190529191110.GB5703@avx2
Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Since commit 2724273e8fd0 ("vmcore: add API to collect hardware dump in
second kernel"), drivers are allowed to add device related dump data to
vmcore as they want by using the device dump API. This has a potential
issue, the data is stored in memory, drivers may append too much data
and use too much memory. The vmcore is typically used in a kdump kernel
which runs in a pre-reserved small chunk of memory. So as a result it
will make kdump unusable at all due to OOM issues.So introduce new 'novmcoredd' command line option. User can disable
device dump to reduce memory usage. This is helpful if device dump is
using too much memory, disabling device dump could make sure a regular
vmcore without device dump data is still available.[akpm@linux-foundation.org: tweak documentation]
[akpm@linux-foundation.org: vmcore.c needs moduleparam.h]
Link: http://lkml.kernel.org/r/20190528111856.7276-1-kasong@redhat.com
Signed-off-by: Kairui Song
Acked-by: Dave Young
Reviewed-by: Bhupesh Sharma
Cc: Rahul Lakkireddy
Cc: "David S . Miller"
Cc: Eric Biederman
Cc: Alexey Dobriyan
Cc: Baoquan He
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Pull rst conversion of docs from Mauro Carvalho Chehab:
"As agreed with Jon, I'm sending this big series directly to you, c/c
him, as this series required a special care, in order to avoid
conflicts with other trees"* tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (77 commits)
docs: kbuild: fix build with pdf and fix some minor issues
docs: block: fix pdf output
docs: arm: fix a breakage with pdf output
docs: don't use nested tables
docs: gpio: add sysfs interface to the admin-guide
docs: locking: add it to the main index
docs: add some directories to the main documentation index
docs: add SPDX tags to new index files
docs: add a memory-devices subdir to driver-api
docs: phy: place documentation under driver-api
docs: serial: move it to the driver-api
docs: driver-api: add remaining converted dirs to it
docs: driver-api: add xilinx driver API documentation
docs: driver-api: add a series of orphaned documents
docs: admin-guide: add a series of orphaned documents
docs: cgroup-v1: add it to the admin-guide book
docs: aoe: add it to the driver-api book
docs: add some documentation dirs to the driver-api book
docs: driver-model: move it to the driver-api book
docs: lp855x-driver.rst: add it to the driver-api book
... -
This fixes two problems reported with the cmdline simplification and
cleanup last year:- the setproctitle() special cases didn't quite match the original
semantics, and it can be noticeable:https://lore.kernel.org/lkml/alpine.LNX.2.21.1904052326230.3249@kich.toxcorp.com/
- it could leak an uninitialized byte from the temporary buffer under
the right (wrong) circustances:https://lore.kernel.org/lkml/20190712160913.17727-1-izbyshev@ispras.ru/
It rewrites the logic entirely, splitting it into two separate commits
(and two separate functions) for the two different cases ("unedited
cmdline" vs "setproctitle() has been used to change the command line").* proc-cmdline:
/proc//cmdline: add back the setproctitle() special case
/proc//cmdline: remove all the special cases -
This makes the setproctitle() special case very explicit indeed, and
handles it with a separate helper function entirely. In the process, it
re-instates the original semantics of simply stopping at the first NUL
character when the original last NUL character is no longer there.[ The original semantics can still be seen in mm/util.c: get_cmdline()
that is limited to a fixed-size buffer ]This makes the logic about when we use the string lengths etc much more
obvious, and makes it easier to see what we do and what the two very
different cases are.Note that even when we allow walking past the end of the argument array
(because the setproctitle() might have overwritten and overflowed the
original argv[] strings), we only allow it when it overflows into the
environment region if it is immediately adjacent.[ Fixed for missing 'count' checks noted by Alexey Izbyshev ]
Link: https://lore.kernel.org/lkml/alpine.LNX.2.21.1904052326230.3249@kich.toxcorp.com/
Fixes: 5ab827189965 ("fs/proc: simplify and clarify get_mm_cmdline() function")
Cc: Jakub Jankowski
Cc: Alexey Dobriyan
Cc: Alexey Izbyshev
Signed-off-by: Linus Torvalds -
Start off with a clean slate that only reads exactly from arg_start to
arg_end, without any oddities. This simplifies the code and in the
process removes the case that caused us to potentially leak an
uninitialized byte from the temporary kernel buffer.Note that in order to start from scratch with an understandable base,
this simplifies things _too_ much, and removes all the legacy logic to
handle setproctitle() having changed the argument strings.We'll add back those special cases very differently in the next commit.
Link: https://lore.kernel.org/lkml/20190712160913.17727-1-izbyshev@ispras.ru/
Fixes: f5b65348fd77 ("proc: fix missing final NUL in get_mm_cmdline() rewrite")
Cc: Alexey Izbyshev
Cc: Alexey Dobriyan
Signed-off-by: Linus Torvalds
15 Jul, 2019
2 commits
-
The stuff under sysctl describes /sys interface from userspace
point of view. So, add it to the admin-guide and remove the
:orphan: from its index file.Signed-off-by: Mauro Carvalho Chehab
-
Pull HMM updates from Jason Gunthorpe:
"Improvements and bug fixes for the hmm interface in the kernel:- Improve clarity, locking and APIs related to the 'hmm mirror'
feature merged last cycle. In linux-next we now see AMDGPU and
nouveau to be using this API.- Remove old or transitional hmm APIs. These are hold overs from the
past with no users, or APIs that existed only to manage cross tree
conflicts. There are still a few more of these cleanups that didn't
make the merge window cut off.- Improve some core mm APIs:
- export alloc_pages_vma() for driver use
- refactor into devm_request_free_mem_region() to manage
DEVICE_PRIVATE resource reservations
- refactor duplicative driver code into the core dev_pagemap
struct- Remove hmm wrappers of improved core mm APIs, instead have drivers
use the simplified API directly- Remove DEVICE_PUBLIC
- Simplify the kconfig flow for the hmm users and core code"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (42 commits)
mm: don't select MIGRATE_VMA_HELPER from HMM_MIRROR
mm: remove the HMM config option
mm: sort out the DEVICE_PRIVATE Kconfig mess
mm: simplify ZONE_DEVICE page private data
mm: remove hmm_devmem_add
mm: remove hmm_vma_alloc_locked_page
nouveau: use devm_memremap_pages directly
nouveau: use alloc_page_vma directly
PCI/P2PDMA: use the dev_pagemap internal refcount
device-dax: use the dev_pagemap internal refcount
memremap: provide an optional internal refcount in struct dev_pagemap
memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag
memremap: remove the data field in struct dev_pagemap
memremap: add a migrate_to_ram method to struct dev_pagemap_ops
memremap: lift the devmap_enable manipulation into devm_memremap_pages
memremap: pass a struct dev_pagemap to ->kill and ->cleanup
memremap: move dev_pagemap callbacks into a separate structure
memremap: validate the pagemap type passed to devm_memremap_pages
mm: factor out a devm_request_free_mem_region helper
mm: export alloc_pages_vma
...
13 Jul, 2019
9 commits
-
Commit ef08e3b4981a ("[PATCH] cpusets: confine oom_killer to
mem_exclusive cpuset") introduces a heuristic where a potential
oom-killer victim is skipped if the intersection of the potential victim
and the current (the process triggered the oom) is empty based on the
reason that killing such victim most probably will not help the current
allocating process.However the commit 7887a3da753e ("[PATCH] oom: cpuset hint") changed the
heuristic to just decrease the oom_badness scores of such potential
victim based on the reason that the cpuset of such processes might have
changed and previously they may have allocated memory on mems where the
current allocating process can allocate from.Unintentionally 7887a3da753e ("[PATCH] oom: cpuset hint") introduced a
side effect as the oom_badness is also exposed to the user space through
/proc/[pid]/oom_score, so, readers with different cpusets can read
different oom_score of the same process.Later, commit 6cf86ac6f36b ("oom: filter tasks not sharing the same
cpuset") fixed the side effect introduced by 7887a3da753e by moving the
cpuset intersection back to only oom-killer context and out of
oom_badness. However the combination of ab290adbaf8f ("oom: make
oom_unkillable_task() helper function") and 26ebc984913b ("oom:
/proc//oom_score treat kernel thread honestly") unintentionally
brought back the cpuset intersection check into the oom_badness
calculation function.Other than doing cpuset/mempolicy intersection from oom_badness, the memcg
oom context is also doing cpuset/mempolicy intersection which is quite
wrong and is caught by syzcaller with the following report:kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 28426 Comm: syz-executor.5 Not tainted 5.2.0-rc3-next-20190607
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:194 [inline]
RIP: 0010:has_intersects_mems_allowed mm/oom_kill.c:84 [inline]
RIP: 0010:oom_unkillable_task mm/oom_kill.c:168 [inline]
RIP: 0010:oom_unkillable_task+0x180/0x400 mm/oom_kill.c:155
Code: c1 ea 03 80 3c 02 00 0f 85 80 02 00 00 4c 8b a3 10 07 00 00 48 b8 00
00 00 00 00 fc ff df 4d 8d 74 24 10 4c 89 f2 48 c1 ea 03 3c 02 00 0f
85 67 02 00 00 49 8b 44 24 10 4c 8d a0 68 fa ff ff
RSP: 0018:ffff888000127490 EFLAGS: 00010a03
RAX: dffffc0000000000 RBX: ffff8880a4cd5438 RCX: ffffffff818dae9c
RDX: 100000000c3cc602 RSI: ffffffff818dac8d RDI: 0000000000000001
RBP: ffff8880001274d0 R08: ffff888000086180 R09: ffffed1015d26be0
R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: 8000000061e63007
R13: 0000000000000000 R14: 8000000061e63017 R15: 1ffff11000024ea6
FS: 00005555561f5940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000607304 CR3: 000000009237e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
oom_evaluate_task+0x49/0x520 mm/oom_kill.c:321
mem_cgroup_scan_tasks+0xcc/0x180 mm/memcontrol.c:1169
select_bad_process mm/oom_kill.c:374 [inline]
out_of_memory mm/oom_kill.c:1088 [inline]
out_of_memory+0x6b2/0x1280 mm/oom_kill.c:1035
mem_cgroup_out_of_memory+0x1ca/0x230 mm/memcontrol.c:1573
mem_cgroup_oom mm/memcontrol.c:1905 [inline]
try_charge+0xfbe/0x1480 mm/memcontrol.c:2468
mem_cgroup_try_charge+0x24d/0x5e0 mm/memcontrol.c:6073
mem_cgroup_try_charge_delay+0x1f/0xa0 mm/memcontrol.c:6088
do_huge_pmd_wp_page_fallback+0x24f/0x1680 mm/huge_memory.c:1201
do_huge_pmd_wp_page+0x7fc/0x2160 mm/huge_memory.c:1359
wp_huge_pmd mm/memory.c:3793 [inline]
__handle_mm_fault+0x164c/0x3eb0 mm/memory.c:4006
handle_mm_fault+0x3b7/0xa90 mm/memory.c:4053
do_user_addr_fault arch/x86/mm/fault.c:1455 [inline]
__do_page_fault+0x5ef/0xda0 arch/x86/mm/fault.c:1521
do_page_fault+0x71/0x57d arch/x86/mm/fault.c:1552
page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1156
RIP: 0033:0x400590
Code: 06 e9 49 01 00 00 48 8b 44 24 10 48 0b 44 24 28 75 1f 48 8b 14 24 48
8b 7c 24 20 be 04 00 00 00 e8 f5 56 00 00 48 8b 74 24 08 06 e9 1e 01
00 00 48 8b 44 24 08 48 8b 14 24 be 04 00 00 00 8b
RSP: 002b:00007fff7bc49780 EFLAGS: 00010206
RAX: 0000000000000001 RBX: 0000000000760000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 000000002000cffc RDI: 0000000000000001
RBP: fffffffffffffffe R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000760008
R13: 00000000004c55f2 R14: 0000000000000000 R15: 00007fff7bc499b0
Modules linked in:
---[ end trace a65689219582ffff ]---
RIP: 0010:__read_once_size include/linux/compiler.h:194 [inline]
RIP: 0010:has_intersects_mems_allowed mm/oom_kill.c:84 [inline]
RIP: 0010:oom_unkillable_task mm/oom_kill.c:168 [inline]
RIP: 0010:oom_unkillable_task+0x180/0x400 mm/oom_kill.c:155
Code: c1 ea 03 80 3c 02 00 0f 85 80 02 00 00 4c 8b a3 10 07 00 00 48 b8 00
00 00 00 00 fc ff df 4d 8d 74 24 10 4c 89 f2 48 c1 ea 03 3c 02 00 0f
85 67 02 00 00 49 8b 44 24 10 4c 8d a0 68 fa ff ff
RSP: 0018:ffff888000127490 EFLAGS: 00010a03
RAX: dffffc0000000000 RBX: ffff8880a4cd5438 RCX: ffffffff818dae9c
RDX: 100000000c3cc602 RSI: ffffffff818dac8d RDI: 0000000000000001
RBP: ffff8880001274d0 R08: ffff888000086180 R09: ffffed1015d26be0
R10: ffffed1015d26bdf R11: ffff8880ae935efb R12: 8000000061e63007
R13: 0000000000000000 R14: 8000000061e63017 R15: 1ffff11000024ea6
FS: 00005555561f5940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f823000 CR3: 000000009237e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600The fix is to decouple the cpuset/mempolicy intersection check from
oom_unkillable_task() and make sure cpuset/mempolicy intersection check is
only done in the global oom context.[shakeelb@google.com: change function name and update comment]
Link: http://lkml.kernel.org/r/20190628152421.198994-3-shakeelb@google.com
Link: http://lkml.kernel.org/r/20190624212631.87212-3-shakeelb@google.com
Signed-off-by: Shakeel Butt
Reported-by: syzbot+d0fc9d3c166bc5e4a94b@syzkaller.appspotmail.com
Acked-by: Roman Gushchin
Acked-by: Michal Hocko
Cc: David Rientjes
Cc: Johannes Weiner
Cc: KOSAKI Motohiro
Cc: Nick Piggin
Cc: Paul Jackson
Cc: Tetsuo Handa
Cc: Vladimir Davydov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
oom_unkillable_task() can be called from three different contexts i.e.
global OOM, memcg OOM and oom_score procfs interface. At the moment
oom_unkillable_task() does a task_in_mem_cgroup() check on the given
process. Since there is no reason to perform task_in_mem_cgroup()
check for global OOM and oom_score procfs interface, those contexts
provide NULL memcg and skips the task_in_mem_cgroup() check. However
for memcg OOM context, the oom_unkillable_task() is always called from
mem_cgroup_scan_tasks() and thus task_in_mem_cgroup() check becomes
redundant and effectively dead code. So, just remove the
task_in_mem_cgroup() check altogether.Link: http://lkml.kernel.org/r/20190624212631.87212-2-shakeelb@google.com
Signed-off-by: Shakeel Butt
Signed-off-by: Tetsuo Handa
Acked-by: Roman Gushchin
Acked-by: Michal Hocko
Cc: David Rientjes
Cc: Johannes Weiner
Cc: KOSAKI Motohiro
Cc: Nick Piggin
Cc: Paul Jackson
Cc: Vladimir Davydov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Vmalloc() is getting more and more used these days (kernel stacks, bpf and
percpu allocator are new top users), and the total % of memory consumed by
vmalloc() can be pretty significant and changes dynamically./proc/meminfo is the best place to display this information: its top goal
is to show top consumers of the memory.Since the VmallocUsed field in /proc/meminfo is not in use for quite a
long time (it has been defined to 0 by a5ad88ce8c7f ("mm: get rid of
'vmalloc_info' from /proc/meminfo")), let's reuse it for showing the
actual physical memory consumption of vmalloc().Link: http://lkml.kernel.org/r/20190417194002.12369-3-guro@fb.com
Signed-off-by: Roman Gushchin
Acked-by: Johannes Weiner
Acked-by: Vlastimil Babka
Reviewed-by: Andrew Morton
Cc: Matthew Wilcox
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Report separate components (anon, file, and shmem) for PSS in
smaps_rollup.This helps understand and tune the memory manager behavior in consumer
devices, particularly mobile devices. Many of them (e.g. chromebooks and
Android-based devices) use zram for anon memory, and perform disk reads
for discarded file pages. The difference in latency is large (e.g.
reading a single page from SSD is 30 times slower than decompressing a
zram page on one popular device), thus it is useful to know how much of
the PSS is anon vs. file.All the information is already present in /proc/pid/smaps, but much more
expensive to obtain because of the large size of that procfs entry.This patch also removes a small code duplication in smaps_account, which
would have gotten worse otherwise.Also updated Documentation/filesystems/proc.txt (the smaps section was a
bit stale, and I added a smaps_rollup section) and
Documentation/ABI/testing/procfs-smaps_rollup.[semenzato@chromium.org: v5]
Link: http://lkml.kernel.org/r/20190626234333.44608-1-semenzato@chromium.org
Link: http://lkml.kernel.org/r/20190626180429.174569-1-semenzato@chromium.org
Signed-off-by: Luigi Semenzato
Acked-by: Yu Zhao
Cc: Sonny Rao
Cc: Yu Zhao
Cc: Brian Geffon
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Do not remain stuck forever if something goes wrong. Using a killable
lock permits cleanup of stuck tasks and simplifies investigation.It seems ->d_revalidate() could return any error (except ECHILD) to abort
validation and pass error as result of lookup sequence.[akpm@linux-foundation.org: fix proc_map_files_lookup() return value, per Andrei]
Link: http://lkml.kernel.org/r/156007493995.3335.9595044802115356911.stgit@buzz
Signed-off-by: Konstantin Khlebnikov
Reviewed-by: Roman Gushchin
Reviewed-by: Cyrill Gorcunov
Reviewed-by: Kirill Tkhai
Acked-by: Michal Hocko
Cc: Alexey Dobriyan
Cc: Al Viro
Cc: Matthew Wilcox
Cc: Michal Koutný
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Do not remain stuck forever if something goes wrong. Using a killable
lock permits cleanup of stuck tasks and simplifies investigation.Replace the only unkillable mmap_sem lock in clear_refs_write().
Link: http://lkml.kernel.org/r/156007493826.3335.5424884725467456239.stgit@buzz
Signed-off-by: Konstantin Khlebnikov
Reviewed-by: Roman Gushchin
Reviewed-by: Cyrill Gorcunov
Reviewed-by: Kirill Tkhai
Acked-by: Michal Hocko
Cc: Alexey Dobriyan
Cc: Al Viro
Cc: Matthew Wilcox
Cc: Michal Koutný
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Do not remain stuck forever if something goes wrong. Using a killable
lock permits cleanup of stuck tasks and simplifies investigation.Link: http://lkml.kernel.org/r/156007493638.3335.4872164955523928492.stgit@buzz
Signed-off-by: Konstantin Khlebnikov
Reviewed-by: Roman Gushchin
Reviewed-by: Cyrill Gorcunov
Reviewed-by: Kirill Tkhai
Acked-by: Michal Hocko
Cc: Alexey Dobriyan
Cc: Al Viro
Cc: Matthew Wilcox
Cc: Michal Koutný
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Do not remain stuck forever if something goes wrong. Using a killable
lock permits cleanup of stuck tasks and simplifies investigation.Link: http://lkml.kernel.org/r/156007493429.3335.14666825072272692455.stgit@buzz
Signed-off-by: Konstantin Khlebnikov
Reviewed-by: Roman Gushchin
Reviewed-by: Cyrill Gorcunov
Reviewed-by: Kirill Tkhai
Acked-by: Michal Hocko
Cc: Alexey Dobriyan
Cc: Al Viro
Cc: Matthew Wilcox
Cc: Michal Koutný
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Do not remain stuck forever if something goes wrong. Using a killable
lock permits cleanup of stuck tasks and simplifies investigation.This function is also used for /proc/pid/smaps.
Link: http://lkml.kernel.org/r/156007493160.3335.14447544314127417266.stgit@buzz
Signed-off-by: Konstantin Khlebnikov
Reviewed-by: Roman Gushchin
Reviewed-by: Cyrill Gorcunov
Reviewed-by: Kirill Tkhai
Acked-by: Michal Hocko
Cc: Alexey Dobriyan
Cc: Al Viro
Cc: Matthew Wilcox
Cc: Michal Koutný
Cc: Oleg Nesterov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
