Pull tracing updates from Steven Rostedt:
- kprobes: Restructured stack unwinder to show properly on x86 when a
stack dump happens from a kretprobe callback.
- Fix to bootconfig parsing
- Have tracefs allow owner and group permissions by default (only
denying others). There's been pressure to allow non root to tracefs
in a controlled fashion, and using groups is probably the safest.
- Bootconfig memory managament updates.
- Bootconfig clean up to have the tools directory be less dependent on
changes in the kernel tree.
- Allow perf to be traced by function tracer.
- Rewrite of function graph tracer to be a callback from the function
tracer instead of having its own trampoline (this change will happen
on an arch by arch basis, and currently only x86_64 implements it).
- Allow multiple direct trampolines (bpf hooks to functions) be batched
together in one synchronization.
- Allow histogram triggers to add variables that can perform
calculations against the event's fields.
- Use the linker to determine architecture callbacks from the ftrace
trampoline to allow for proper parameter prototypes and prevent
warnings from the compiler.
- Extend histogram triggers to key off of variables.
- Have trace recursion use bit magic to determine preempt context over
if branches.
- Have trace recursion disable preemption as all use cases do anyway.
- Added testing for verification of tracing utilities.
- Various small clean ups and fixes.
* tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits)
tracing/histogram: Fix semicolon.cocci warnings
tracing/histogram: Fix documentation inline emphasis warning
tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together
tracing: Show size of requested perf buffer
bootconfig: Initialize ret in xbc_parse_tree()
ftrace: do CPU checking after preemption disabled
ftrace: disable preemption when recursion locked
tracing/histogram: Document expression arithmetic and constants
tracing/histogram: Optimize division by a power of 2
tracing/histogram: Covert expr to const if both operands are constants
tracing/histogram: Simplify handling of .sym-offset in expressions
tracing: Fix operator precedence for hist triggers expression
tracing: Add division and multiplication support for hist triggers
tracing: Add support for creating hist trigger variables from literal
selftests/ftrace: Stop tracing while reading the trace file by default
MAINTAINERS: Update KPROBES and TRACING entries
test_kprobes: Move it from kernel/ to lib/
docs, kprobes: Remove invalid URL and add new reference
samples/kretprobes: Fix return value if register_kretprobe() failed
lib/bootconfig: Fix the xbc_get_info kerneldoc
...
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
Pull asm-generic updates from Arnd Bergmann:
"The main content for 5.15 is a series that cleans up the handling of
strncpy_from_user() and strnlen_user(), removing a lot of slightly
incorrect versions of these in favor of the lib/strn*.c helpers that
implement these correctly and more efficiently.
The only architectures that retain a private version now are mips,
ia64, um and parisc. I had offered to convert those at all, but Thomas
Bogendoerfer wanted to keep the mips version for the moment until he
had a chance to do regression testing.
The branch also contains two patches for bitops and for ffs()"
* tag 'asm-generic-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
bitops/non-atomic: make @nr unsigned to avoid any DIV
asm-generic: ffs: Drop bogus reference to ffz location
asm-generic: reverse GENERIC_{STRNCPY_FROM,STRNLEN}_USER symbols
asm-generic: remove extra strn{cpy_from,len}_user declarations
asm-generic: uaccess: remove inline strncpy_from_user/strnlen_user
s390: use generic strncpy/strnlen from_user
microblaze: use generic strncpy/strnlen from_user
csky: use generic strncpy/strnlen from_user
arc: use generic strncpy/strnlen from_user
hexagon: use generic strncpy/strnlen from_user
h8300: remove stale strncpy_from_user
asm-generic/uaccess.h: remove __strncpy_from_user/__strnlen_user
Remove the microblaze implemenation of strncpy/strnlen and instead use
the generic versions. The microblaze version is fairly slow because it
always does byte accesses even for aligned data, and it lacks a checks
for user_addr_max().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull misc fs updates from Jan Kara:
"The new quotactl_fd() syscall (remake of quotactl_path() syscall that
got introduced & disabled in 5.13 cycle), and couple of udf, reiserfs,
isofs, and writeback fixes and cleanups"
* tag 'fs_for_v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
writeback: fix obtain a reference to a freeing memcg css
quota: remove unnecessary oom message
isofs: remove redundant continue statement
quota: Wire up quotactl_fd syscall
quota: Change quotactl_path() systcall to an fd-based one
reiserfs: Remove unneed check in reiserfs_write_full_page()
udf: Fix NULL pointer dereference in udf_symlink function
reiserfs: add check for invalid 1st journal block
In commit fa8b90070a ("quota: wire up quotactl_path") we have wired up
new quotactl_path syscall. However some people in LWN discussion have
objected that the path based syscall is missing dirfd and flags argument
which is mostly standard for contemporary path based syscalls. Indeed
they have a point and after a discussion with Christian Brauner and
Sascha Hauer I've decided to disable the syscall for now and update its
API. Since there is no userspace currently using that syscall and it
hasn't been released in any major release, we should be fine.
CC: Christian Brauner <christian.brauner@ubuntu.com>
CC: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/lkml/20210512153621.n5u43jsytbik4yze@wittgenstein
Signed-off-by: Jan Kara <jack@suse.cz>
Pull Landlock LSM from James Morris:
"Add Landlock, a new LSM from Mickaël Salaün.
Briefly, Landlock provides for unprivileged application sandboxing.
From Mickaël's cover letter:
"The goal of Landlock is to enable to restrict ambient rights (e.g.
global filesystem access) for a set of processes. Because Landlock
is a stackable LSM [1], it makes possible to create safe security
sandboxes as new security layers in addition to the existing
system-wide access-controls. This kind of sandbox is expected to
help mitigate the security impact of bugs or unexpected/malicious
behaviors in user-space applications. Landlock empowers any
process, including unprivileged ones, to securely restrict
themselves.
Landlock is inspired by seccomp-bpf but instead of filtering
syscalls and their raw arguments, a Landlock rule can restrict the
use of kernel objects like file hierarchies, according to the
kernel semantic. Landlock also takes inspiration from other OS
sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD
Pledge/Unveil.
In this current form, Landlock misses some access-control features.
This enables to minimize this patch series and ease review. This
series still addresses multiple use cases, especially with the
combined use of seccomp-bpf: applications with built-in sandboxing,
init systems, security sandbox tools and security-oriented APIs [2]"
The cover letter and v34 posting is here:
https://lore.kernel.org/linux-security-module/20210422154123.13086-1-mic@digikod.net/
See also:
https://landlock.io/
This code has had extensive design discussion and review over several
years"
Link: https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@schaufler-ca.com/ [1]
Link: https://lore.kernel.org/lkml/f646e1c7-33cf-333f-070c-0a40ad0468cd@digikod.net/ [2]
* tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
landlock: Enable user space to infer supported features
landlock: Add user and kernel documentation
samples/landlock: Add a sandbox manager example
selftests/landlock: Add user space tests
landlock: Add syscall implementations
arch: Wire up Landlock syscalls
fs,security: Add sb_delete hook
landlock: Support filesystem access-control
LSM: Infrastructure management of the superblock
landlock: Add ptrace restrictions
landlock: Set up the security framework and manage credentials
landlock: Add ruleset and domain management
landlock: Add object management
Pull Microblaze updates from Michal Simek:
"No new features, just about cleaning up some code and moving to
generic syscall solution used by other architectures:
- Switch to generic syscall scripts
- Some small fixes"
* tag 'microblaze-v5.13' of git://git.monstr.eu/linux-2.6-microblaze:
microblaze: add 'fallthrough' to memcpy/memset/memmove
microblaze: Fix a typo
microblaze: tag highmem_setup() with __meminit
microblaze: syscalls: switch to generic syscallhdr.sh
microblaze: syscalls: switch to generic syscalltbl.sh
Pull io_uring thread rewrite from Jens Axboe:
"This converts the io-wq workers to be forked off the tasks in question
instead of being kernel threads that assume various bits of the
original task identity.
This kills > 400 lines of code from io_uring/io-wq, and it's the worst
part of the code. We've had several bugs in this area, and the worry
is always that we could be missing some pieces for file types doing
unusual things (recent /dev/tty example comes to mind, userfaultfd
reads installing file descriptors is another fun one... - both of
which need special handling, and I bet it's not the last weird oddity
we'll find).
With these identical workers, we can have full confidence that we're
never missing anything. That, in itself, is a huge win. Outside of
that, it's also more efficient since we're not wasting space and code
on tracking state, or switching between different states.
I'm sure we're going to find little things to patch up after this
series, but testing has been pretty thorough, from the usual
regression suite to production. Any issue that may crop up should be
manageable.
There's also a nice series of further reductions we can do on top of
this, but I wanted to get the meat of it out sooner rather than later.
The general worry here isn't that it's fundamentally broken. Most of
the little issues we've found over the last week have been related to
just changes in how thread startup/exit is done, since that's the main
difference between using kthreads and these kinds of threads. In fact,
if all goes according to plan, I want to get this into the 5.10 and
5.11 stable branches as well.
That said, the changes outside of io_uring/io-wq are:
- arch setup, simple one-liner to each arch copy_thread()
implementation.
- Removal of net and proc restrictions for io_uring, they are no
longer needed or useful"
* tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits)
io-wq: remove now unused IO_WQ_BIT_ERROR
io_uring: fix SQPOLL thread handling over exec
io-wq: improve manager/worker handling over exec
io_uring: ensure SQPOLL startup is triggered before error shutdown
io-wq: make buffered file write hashed work map per-ctx
io-wq: fix race around io_worker grabbing
io-wq: fix races around manager/worker creation and task exit
io_uring: ensure io-wq context is always destroyed for tasks
arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
io_uring: cleanup ->user usage
io-wq: remove nr_process accounting
io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS
net: remove cmsg restriction from io_uring based send/recvmsg calls
Revert "proc: don't allow async path resolution of /proc/self components"
Revert "proc: don't allow async path resolution of /proc/thread-self components"
io_uring: move SQPOLL thread io-wq forked worker
io-wq: make io_wq_fork_thread() available to other users
io-wq: only remove worker from free_list, if it was there
io_uring: remove io_identity
io_uring: remove any grabbing of context
...
Pull Kbuild updates from Masahiro Yamada:
- Fix false-positive build warnings for ARCH=ia64 builds
- Optimize dictionary size for module compression with xz
- Check the compiler and linker versions in Kconfig
- Fix misuse of extra-y
- Support DWARF v5 debug info
- Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
exceeded the limit
- Add generic syscall{tbl,hdr}.sh for cleanups across arches
- Minor cleanups of genksyms
- Minor cleanups of Kconfig
* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
kbuild: remove deprecated 'always' and 'hostprogs-y/m'
kbuild: parse C= and M= before changing the working directory
kbuild: reuse this-makefile to define abs_srctree
kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
kconfig: omit --oldaskconfig option for 'make config'
kconfig: fix 'invalid option' for help option
kconfig: remove dead code in conf_askvalue()
kconfig: clean up nested if-conditionals in check_conf()
kconfig: Remove duplicate call to sym_get_string_value()
Makefile: Remove # characters from compiler string
Makefile: reuse CC_VERSION_TEXT
kbuild: check the minimum linker version in Kconfig
kbuild: remove ld-version macro
scripts: add generic syscallhdr.sh
scripts: add generic syscalltbl.sh
arch: syscalls: remove $(srctree)/ prefix from syscall tables
arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
gen_compile_commands: prune some directories
kbuild: simplify access to the kernel's version
...
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the
sense that we don't assign ->set_child_tid with our own structure. Just
ensure that every arch sets up the PF_IO_WORKER threads like kthreads
in the arch implementation of copy_thread().
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The 'syscall' variables are not directly used in the commands.
Remove the $(srctree)/ prefix because we can rely on VPATH.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The rules in these Makefiles cannot detect the command line change
because the prerequisite 'FORCE' is missing.
Adding 'FORCE' will result in the headers being rebuilt every time
because the 'targets' additions are also wrong; the file paths in
'targets' must be relative to the current Makefile.
Fix all of them so the if_changed rules work correctly.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
