The software breakpoint handlers are hooked in directly from ptrace,
which makes it difficult to add additional handlers for things like
kprobes and kgdb.
This patch moves the handling code into debug-monitors.c, where we can
dispatch to different debug subsystems more easily.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This adds support for advertising the presence of ARMv8 Crypto
Extensions in the Aarch32 execution state to 32-bit ELF binaries
running in 32-bit compat mode under the arm64 kernel.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add support for the ELF auxv entry AT_HWCAP2 when running 32-bit
ELF binaries in compat mode.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add ELF_HWCAP2 to the set of auxv entries that is passed to
a 32-bit ELF program running in 32-bit compat mode under a
64-bit kernel.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Advertise the optional cryptographic and CRC32 instructions to
user space where present. Several hwcap bits [3-7] are allocated.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
[bit 2 is taken now so use bits 3-7 instead]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Under arm64 elf_hwcap is a 32 bit quantity, but it is stored in
a 64 bit auxiliary ELF field and glibc reads hwcap as 64 bit.
This patch widens elf_hwcap to be 64 bit.
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Take the hwcaps changes from 46efe547ac to
facilitate cherry-picking later hwcaps changes, while skipping the timer
changes that actually enable event streams for now. The timer changes
depend on some non-trivial changes made after 3.10, and can safely be
dropped: the kernel will just continue reporting that HWCAP_EVTSTRM is
not available.
Bug: 17431179
Change-Id: I41548846f8cd7ae8147a2b115cc0f84708e29552
Signed-off-by: Greg Hackmann <ghackmann@google.com>
A port of 8608d7c441 to ARM64. Both the
original code and this port are limited to dumping kernel addresses, so
don't bother if the registers are from a userspace process.
Change-Id: Idc76804c54efaaeb70311cbb500c54db6dac4525
Signed-off-by: Greg Hackmann <ghackmann@google.com>
From: Cylen Yao <cylen.yao@mediatek.com>
common_tunables should be static.
Change-Id: I502ee3062bece5082fea7861eff2f6237e25cede
Signed-off-by: Todd Poynor <toddpoynor@google.com>
There are a couple of seq_files which use the single_open() interface.
This interface requires that the whole output must fit into a single
buffer.
E.g. for /proc/stat allocation failures have been observed because an
order-4 memory allocation failed due to memory fragmentation. In such
situations reading /proc/stat is not possible anymore.
Therefore change the seq_file code to fallback to vmalloc allocations
which will usually result in a couple of order-0 allocations and hence
also work if memory is fragmented.
For reference a call trace where reading from /proc/stat failed:
sadc: page allocation failure: order:4, mode:0x1040d0
CPU: 1 PID: 192063 Comm: sadc Not tainted 3.10.0-123.el7.s390x #1
[...]
Call Trace:
show_stack+0x6c/0xe8
warn_alloc_failed+0xd6/0x138
__alloc_pages_nodemask+0x9da/0xb68
__get_free_pages+0x2e/0x58
kmalloc_order_trace+0x44/0xc0
stat_open+0x5a/0xd8
proc_reg_open+0x8a/0x140
do_dentry_open+0x1bc/0x2c8
finish_open+0x46/0x60
do_last+0x382/0x10d0
path_openat+0xc8/0x4f8
do_filp_open+0x46/0xa8
do_sys_open+0x114/0x1f0
sysc_tracego+0x14/0x1a
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: David Rientjes <rientjes@google.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thorsten Diehl <thorsten.diehl@de.ibm.com>
Cc: Andrea Righi <andrea@betterlinux.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Stefan Bader <stefan.bader@canonical.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts:
fs/seq_file.c
Change-Id: I009080dd017b020ffd5e812e5b472bdb8349217a
too many places open-code it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
mm/util.c
security/apparmor/include/apparmor.h
Change-Id: Ie8602e0199282dc462921cb7217158d1998853b0
Now arm64 defers reloading FPSIMD state, but this optimization also
introduces the bug after cpu resume back from low power mode.
The reason is after the cpu has been powered off, s/w need set the
cpu's fpsimd_last_state to NULL so that it will force to reload
FPSIMD state for the thread, otherwise there has the chance to meet
the condition for both the task's fpsimd_state.cpu field contains the
id of the current cpu, and the cpu's fpsimd_last_state per-cpu variable
points to the task's fpsimd_state, so finally kernel will skip to reload
the context during it return back to userland.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Leo Yan <leoy@marvell.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit 5f888a1d33 (ARM64: perf: support dwarf unwinding in compat mode)
changes user_stack_pointer() to return the compat SP for 32-bit tasks
but without brackets around the whole definition, with possible issues
on the call sites (noticed with a subsequent fix for KSTK_ESP).
Fixes: 5f888a1d33 (ARM64: perf: support dwarf unwinding in compat mode)
Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The KSTK_ESP macro is used to determine the user stack pointer for a
given task. In particular, this is used to to report the '[stack]' VMA
in /proc/self/maps, which is used by Android to determine the stack
location for children of the main thread.
This patch fixes the macro to use user_stack_pointer instead of directly
returning sp. This means that we report w13 instead of sp, since the
former is used as the stack pointer when executing in AArch32 state.
Cc: <stable@vger.kernel.org>
Reported-by: Serban Constantinescu <Serban.Constantinescu@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This is for similarity with thread_saved_(pc|sp) and to avoid some
compiler warnings in the audit code.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add support for unwinding using the dwarf information in compat
mode. Using the correct user stack pointer allows perf to record
the frames correctly in the native and compat modes.
Note that although the dwarf frame unwinding works ok using
libunwind in native mode (on ARMv7 & ARMv8), some changes are
required to the libunwind code for the compat mode. Those changes
are posted separately on the libunwind mailing list.
Tested on ARMv8 platform with v8 and compat v7 binaries, the latter
are statically built.
Signed-off-by: Jean Pihet <jean.pihet@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
pfn_valid() returns a false positive when the lower (64 - PAGE_SHIFT)
bits match a valid pfn but some of the upper bits are set. This caused
a kernel panic in kpageflags_read() when a userspace utility parsed
/proc/*/pagemap, neglected to discard the upper flag bits, and tried to
lseek()+read() from the corresponding offset in /proc/kpageflags.
A valid pfn will never have the upper PAGE_SHIFT bits set, so simply
check for this before passing the pfn to memblock_is_memory().
Change-Id: Ief5d8cd4dd93cbecd545a634a8d5885865cb5970
Signed-off-by: Greg Hackmann <ghackmann@google.com>
This enables support for the generic CPU feature modalias implementation that
wires up optional CPU features to udev based module autoprobing.
A file <asm/cpufeature.h> is provided that maps CPU feature numbers to
elf_hwcap bits, which is the standard way on arm64 to advertise optional CPU
features both internally and to user space.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[catalin.marinas@arm.com: removed unnecessary "!!"]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Conflicts:
arch/arm64/Kconfig
Change-Id: Ief16b3197cd0564d8cf8aa82e9614bcda6399fe5
This adds the function blkcipher_aead_walk_virt_block, which allows the caller
to use the blkcipher walk API to handle the input and output scatterlists.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In order to allow other uses of the blkcipher walk API than the blkcipher
algos themselves, this patch copies some of the transform data members to the
walk struct so the transform is only accessed at walk init time.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch modifies kernel_neon_begin() and kernel_neon_end(), so
they may be called from any context. To address the case where only
a couple of registers are needed, kernel_neon_begin_partial(u32) is
introduced which takes as a parameter the number of bottom 'n' NEON
q-registers required. To mark the end of such a partial section, the
regular kernel_neon_end() should be used.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Conflicts:
arch/arm64/include/asm/neon.h
Change-Id: Ifc7c6aa77e2ab8dd98bb9975cccab54e09693ab7
If a task gets scheduled out and back in again and nothing has touched
its FPSIMD state in the mean time, there is really no reason to reload
it from memory. Similarly, repeated calls to kernel_neon_begin() and
kernel_neon_end() will preserve and restore the FPSIMD state every time.
This patch defers the FPSIMD state restore to the last possible moment,
i.e., right before the task returns to userland. If a task does not return to
userland at all (for any reason), the existing FPSIMD state is preserved
and may be reused by the owning task if it gets scheduled in again on the
same CPU.
This patch adds two more functions to abstract away from straight FPSIMD
register file saves and restores:
- fpsimd_restore_current_state -> ensure current's FPSIMD state is loaded
- fpsimd_flush_task_state -> invalidate live copies of a task's FPSIMD state
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Conflicts:
arch/arm64/kernel/fpsimd.c
Change-Id: Ib1c0d8d0afb3c248cd4d060eb35877530dd92fdc
There are two tacit assumptions in the FPSIMD handling code that will no longer
hold after the next patch that optimizes away some FPSIMD state restores:
. the FPSIMD registers of this CPU contain the userland FPSIMD state of
task 'current';
. when switching to a task, its FPSIMD state will always be restored from
memory.
This patch adds the following functions to abstract away from straight FPSIMD
register file saves and restores:
- fpsimd_preserve_current_state -> ensure current's FPSIMD state is saved
- fpsimd_update_current_state -> replace current's FPSIMD state
Where necessary, the signal handling and fork code are updated to use the above
wrappers instead of poking into the FPSIMD registers directly.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Conflicts:
arch/arm64/kernel/fpsimd.c
Change-Id: I53ae7082427cb1c5cc32e1f2ddbd4218115601ba
This patch adds support for advertising optional CPU features over udev
using the modalias, and for declaring compatibility with/dependency upon
such a feature in a module.
The mapping between feature numbers and actual features should be provided
by the architecture in a file called <asm/cpufeature.h> which exports the
following functions/macros:
- cpu_feature(FEAT), a preprocessor macro that maps token FEAT to a
numeric index;
- bool cpu_have_feature(n), returning whether this CPU has support for
feature #n;
- MAX_CPU_FEATURES, an upper bound for 'n' in the previous function.
The feature can then be enabled by setting CONFIG_GENERIC_CPU_AUTOPROBE
for the architecture.
For instance, a module that registers its module init function using
module_cpu_feature_match(FEAT_X, module_init_function)
will be probed automatically when the CPU's support for the 'FEAT_X'
feature is advertised over udev, and will only allow the module to be
loaded by hand if the 'FEAT_X' feature is supported.
Change-Id: Icae8e3ff347235fc72a5b41279f0afdb34fb161a
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cryptsetup fails on arm64 when using kernel encryption via AF_ALG socket.
See https://bugzilla.redhat.com/show_bug.cgi?id=1122937
The bug is caused by incorrect handling of unaligned data in
arch/arm64/crypto/aes-glue.c. Cryptsetup creates a buffer that is aligned
on 8 bytes, but not on 16 bytes. It opens AF_ALG socket and uses the
socket to encrypt data in the buffer. The arm64 crypto accelerator causes
data corruption or crashes in the scatterwalk_pagedone.
This patch fixes the bug by passing the residue bytes that were not
processed as the last parameter to blkcipher_walk_done.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This fixes the following build failure when building with CONFIG_MODVERSIONS
enabled:
CC [M] arch/arm64/crypto/aes-glue-ce.o
ld: cannot find arch/arm64/crypto/aes-glue-ce.o: No such file or directory
make[1]: *** [arch/arm64/crypto/aes-ce-blk.o] Error 1
make: *** [arch/arm64/crypto] Error 2
The $(obj)/aes-glue-%.o rule only creates $(obj)/.tmp_aes-glue-ce.o, it
should use if_changed_rule instead of if_changed_dep.
Signed-off-by: Andreas Schwab <schwab@suse.de>
[ardb: mention CONFIG_MODVERSIONS in commit log]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patches modifies the GHASH secure hash implementation to switch to a
faster, polynomial multiplication based reduction instead of one that uses
shifts and rotates.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This fixes a bug in the GHASH algorithm resulting in the calculated hash to be
incorrect if the input is presented in chunks whose size is not a multiple of
16 bytes.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Fixes: fdd2389457 ("arm64/crypto: GHASH secure hash using ARMv8 Crypto Extensions")
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This adds ARMv8 implementations of AES in ECB, CBC, CTR and XTS modes,
both for ARMv8 with Crypto Extensions and for plain ARMv8 NEON.
The Crypto Extensions version can only run on ARMv8 implementations that
have support for these optional extensions.
The plain NEON version is a table based yet time invariant implementation.
All S-box substitutions are performed in parallel, leveraging the wide range
of ARMv8's tbl/tbx instructions, and the huge NEON register file, which can
comfortably hold the entire S-box and still have room to spare for doing the
actual computations.
The key expansion routines were borrowed from aes_generic.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds support for the AES-CCM encryption algorithm for CPUs that
have support for the AES part of the ARM v8 Crypto Extensions.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds support for the AES symmetric encryption algorithm for CPUs
that have support for the AES part of the ARM v8 Crypto Extensions.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
This is a port to ARMv8 (Crypto Extensions) of the Intel implementation of the
GHASH Secure Hash (used in the Galois/Counter chaining mode). It relies on the
optional PMULL/PMULL2 instruction (polynomial multiply long, what Intel call
carry-less multiply).
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds support for the SHA-224 and SHA-256 Secure Hash Algorithms
for CPUs that have support for the SHA-2 part of the ARM v8 Crypto Extensions.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds support for the SHA-1 Secure Hash Algorithm for CPUs that
have support for the SHA-1 part of the ARM v8 Crypto Extensions.
Change-Id: I29fafd308e17aff6e0d59938c106fae6ad7fe78e
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Conflicts:
arch/arm64/Makefile
Applying restrictive seccomp filter programs to large or diverse
codebases often requires handling threads which may be started early in
the process lifetime (e.g., by code that is linked in). While it is
possible to apply permissive programs prior to process start up, it is
difficult to further restrict the kernel ABI to those threads after that
point.
This change adds a new seccomp syscall flag to SECCOMP_SET_MODE_FILTER for
synchronizing thread group seccomp filters at filter installation time.
When calling seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
filter) an attempt will be made to synchronize all threads in current's
threadgroup to its new seccomp filter program. This is possible iff all
threads are using a filter that is an ancestor to the filter current is
attempting to synchronize to. NULL filters (where the task is running as
SECCOMP_MODE_NONE) are also treated as ancestors allowing threads to be
transitioned into SECCOMP_MODE_FILTER. If prctrl(PR_SET_NO_NEW_PRIVS,
...) has been set on the calling thread, no_new_privs will be set for
all synchronized threads too. On success, 0 is returned. On failure,
the pid of one of the failing threads will be returned and no filters
will have been applied.
The race conditions against another thread are:
- requesting TSYNC (already handled by sighand lock)
- performing a clone (already handled by sighand lock)
- changing its filter (already handled by sighand lock)
- calling exec (handled by cred_guard_mutex)
The clone case is assisted by the fact that new threads will have their
seccomp state duplicated from their parent before appearing on the tasklist.
Holding cred_guard_mutex means that seccomp filters cannot be assigned
while in the middle of another thread's exec (potentially bypassing
no_new_privs or similar). The call to de_thread() may kill threads waiting
for the mutex.
Changes across threads to the filter pointer includes a barrier.
Based on patches by Will Drewry.
Suggested-by: Julien Tinnes <jln@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
This changes the mode setting helper to allow threads to change the
seccomp mode from another thread. We must maintain barriers to keep
TIF_SECCOMP synchronized with the rest of the seccomp state.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Conflicts:
kernel/seccomp.c
Change-Id: I091ffa55d8f4e83ff02558a55e2b4dc76ac26905
Normally, task_struct.seccomp.filter is only ever read or modified by
the task that owns it (current). This property aids in fast access
during system call filtering as read access is lockless.
Updating the pointer from another task, however, opens up race
conditions. To allow cross-thread filter pointer updates, writes to the
seccomp fields are now protected by the sighand spinlock (which is shared
by all threads in the thread group). Read access remains lockless because
pointer updates themselves are atomic. However, writes (or cloning)
often entail additional checking (like maximum instruction counts)
which require locking to perform safely.
In the case of cloning threads, the child is invisible to the system
until it enters the task list. To make sure a child can't be cloned from
a thread and left in a prior state, seccomp duplication is additionally
moved under the sighand lock. Then parent and child are certain have
the same seccomp state when they exit the lock.
Based on patches by Will Drewry and David Drysdale.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Conflicts:
kernel/fork.c
Change-Id: Ie01ece43b610867013f7d0e0a2a7be0b9077630f
In preparation for adding seccomp locking, move filter creation away
from where it is checked and applied. This will allow for locking where
no memory allocation is happening. The validation, filter attachment,
and seccomp mode setting can all happen under the future locks.
For extreme defensiveness, I've added a BUG_ON check for the calculated
size of the buffer allocation in case BPF_MAXINSN ever changes, which
shouldn't ever happen. The compiler should actually optimize out this
check since the test above it makes it impossible.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Conflicts:
kernel/seccomp.c
Change-Id: I8d89f80a5b4f2826d90474dcea441c41f0af6594
This adds the new "seccomp" syscall with both an "operation" and "flags"
parameter for future expansion. The third argument is a pointer value,
used with the SECCOMP_SET_MODE_FILTER operation. Currently, flags must
be 0. This is functionally equivalent to prctl(PR_SET_SECCOMP, ...).
In addition to the TSYNC flag later in this patch series, there is a
non-zero chance that this syscall could be used for configuring a fixed
argument area for seccomp-tracer-aware processes to pass syscall arguments
in the future. Hence, the use of "seccomp" not simply "seccomp_add_filter"
for this syscall. Additionally, this syscall uses operation, flags,
and user pointer for arguments because strictly passing arguments via
a user pointer would mean seccomp itself would be unable to trivially
filter the seccomp syscall itself.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
Conflicts:
arch/x86/syscalls/syscall_32.tbl
arch/x86/syscalls/syscall_64.tbl
include/uapi/asm-generic/unistd.h
kernel/seccomp.c
Change-Id: Id7a365079829fd9164315dec75d6ee415c29b176
Separates the two mode setting paths to make things more readable with
fewer #ifdefs within function bodies.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
To support splitting mode 1 from mode 2, extract the mode checking and
assignment logic into common functions.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
In preparation for having other callers of the seccomp mode setting
logic, split the prctl entry point away from the core logic that performs
seccomp mode setting.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
