| Age | Commit message (Collapse) | Author |
|---|
|
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
The hardlockup detector on x86 uses a performance counter based on unhalted
CPU cycles and a periodic hrtimer. The hrtimer period is about 2/5 of the
performance counter period, so the hrtimer should fire 2-3 times before the
performance counter NMI fires. The NMI code checks whether the hrtimer
fired since the last invocation. If not, it assumess a hard lockup.
The calculation of those periods is based on the nominal CPU
frequency. Turbo modes increase the CPU clock frequency and therefore
shorten the period of the perf/NMI watchdog. With extreme Turbo-modes (3x
nominal frequency) the perf/NMI period is shorter than the hrtimer period
which leads to false positives.
A simple fix would be to shorten the hrtimer period, but that comes with
the side effect of more frequent hrtimer and softlockup thread wakeups,
which is not desired.
Implement a low pass filter, which checks the perf/NMI period against
kernel time. If the perf/NMI fires before 4/5 of the watchdog period has
elapsed then the event is ignored and postponed to the next perf/NMI.
That solves the problem and avoids the overhead of shorter hrtimer periods
and more frequent softlockup thread wakeups.
Fixes: 58687acba592 ("lockup_detector: Combine nmi_watchdog and softlockup detector")
Reported-and-tested-by: Kan Liang <Kan.liang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: dzickus@redhat.com
Cc: prarit@redhat.com
Cc: ak@linux.intel.com
Cc: babu.moger@oracle.com
Cc: peterz@infradead.org
Cc: eranian@google.com
Cc: acme@redhat.com
Cc: stable@vger.kernel.org
Cc: atomlin@redhat.com
Cc: akpm@linux-foundation.org
Cc: torvalds@linux-foundation.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1708150931310.1886@nanos
|
|
CONFIG_LOCKDEP_COMPLETIONS truly non-interactive
The syntax to turn Kconfig options into non-interactive ones is to not offer
interactive prompt help texts. Remove them.
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
'complete' is an adjective and LOCKDEP_COMPLETE sounds like 'lockdep is complete',
so pick a better name that uses a noun.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/1502960261-16206-3-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Lockdep doesn't have to be made to work with crossrelease and just works
with them. Reword the title so that what the option does is clear.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/1502960261-16206-2-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Crossrelease support added the CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETE
options. It makes little sense to enable them when PROVE_LOCKING is disabled.
Make them non-interative options and part of PROVE_LOCKING to simplify the UI.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/1502960261-16206-1-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Conflicts:
include/linux/mm_types.h
mm/huge_memory.c
I removed the smp_mb__before_spinlock() like the following commit does:
8b1b436dd1cc ("mm, locking: Rework {set,clear,mm}_tlb_flush_pending()")
and fixed up the affected commits.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Commit 1203c8e6fb0a ("fault-inject: simplify access check for fail-nth")
unintentionally broke a conditional statement in should_fail(). Any
faults are not injected in the task context by the change when the
systematic fault injection is not used.
This change restores to the previous correct behaviour.
Link: http://lkml.kernel.org/r/1501633700-3488-1-git-send-email-akinobu.mita@gmail.com
Fixes: 1203c8e6fb0a ("fault-inject: simplify access check for fail-nth")
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Tested-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The break was in the wrong place so file system tests don't work as
intended, leaking memory at each test switch.
[mcgrof@kernel.org: massaged commit subject, noted memory leak issue without the fix]
Link: http://lkml.kernel.org/r/20170802211450.27928-6-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: David Binderman <dcb314@hotmail.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
We accidentally just drop the lock twice instead of taking it and then
releasing it. This isn't a big issue unless you are adding more than
one device to test on, and the kmod.sh doesn't do that yet, however this
obviously is the correct thing to do.
[mcgrof@kernel.org: massaged subject, explain what happens]
Link: http://lkml.kernel.org/r/20170802211450.27928-5-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Parsing with kstrtol() enables values to be negative, and we failed to
check for negative values when parsing with test_dev_config_update_uint_sync()
or test_dev_config_update_uint_range().
test_dev_config_update_uint_range() has a minimum check though so an
issue is not present there. test_dev_config_update_uint_sync() is only
used for the number of threads to use (config_num_threads_store()), and
indeed this would fail with an attempt for a large allocation.
Although the issue is only present in practice with the first fix both
by using kstrtoul() instead of kstrtol().
Link: http://lkml.kernel.org/r/20170802211450.27928-4-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Trivial fix to spelling mistake in snprintf text
[mcgrof@kernel.org: massaged commit message]
Link: http://lkml.kernel.org/r/20170802211450.27928-3-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michal Marek <mmarek@suse.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Although wait_for_completion() and its family can cause deadlock, the
lock correctness validator could not be applied to them until now,
because things like complete() are usually called in a different context
from the waiting context, which violates lockdep's assumption.
Thanks to CONFIG_LOCKDEP_CROSSRELEASE, we can now apply the lockdep
detector to those completion operations. Applied it.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: boqun.feng@gmail.com
Cc: kernel-team@lge.com
Cc: kirill@shutemov.name
Cc: npiggin@gmail.com
Cc: walken@google.com
Cc: willy@infradead.org
Link: http://lkml.kernel.org/r/1502089981-21272-10-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Lockdep is a runtime locking correctness validator that detects and
reports a deadlock or its possibility by checking dependencies between
locks. It's useful since it does not report just an actual deadlock but
also the possibility of a deadlock that has not actually happened yet.
That enables problems to be fixed before they affect real systems.
However, this facility is only applicable to typical locks, such as
spinlocks and mutexes, which are normally released within the context in
which they were acquired. However, synchronization primitives like page
locks or completions, which are allowed to be released in any context,
also create dependencies and can cause a deadlock.
So lockdep should track these locks to do a better job. The 'crossrelease'
implementation makes these primitives also be tracked.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: boqun.feng@gmail.com
Cc: kernel-team@lge.com
Cc: kirill@shutemov.name
Cc: npiggin@gmail.com
Cc: walken@google.com
Cc: willy@infradead.org
Link: http://lkml.kernel.org/r/1502089981-21272-6-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Pull networking fixes from David Miller:
1) Handle notifier registry failures properly in tun/tap driver, from
Tonghao Zhang.
2) Fix bpf verifier handling of subtraction bounds and add a testcase
for this, from Edward Cree.
3) Increase reset timeout in ftgmac100 driver, from Ben Herrenschmidt.
4) Fix use after free in prd_retire_rx_blk_timer_exired() in AF_PACKET,
from Cong Wang.
5) Fix SElinux regression due to recent UDP optimizations, from Paolo
Abeni.
6) We accidently increment IPSTATS_MIB_FRAGFAILS in the ipv6 code
paths, fix from Stefano Brivio.
7) Fix some mem leaks in dccp, from Xin Long.
8) Adjust MDIO_BUS kconfig deps to avoid build errors, from Arnd
Bergmann.
9) Mac address length check and buffer size fixes from Cong Wang.
10) Don't leak sockets in ipv6 udp early demux, from Paolo Abeni.
11) Fix return value when copy_from_user() fails in
bpf_prog_get_info_by_fd(), from Daniel Borkmann.
12) Handle PHY_HALTED properly in phy library state machine, from
Florian Fainelli.
13) Fix OOPS in fib_sync_down_dev(), from Ido Schimmel.
14) Fix truesize calculation in virtio_net which led to performance
regressions, from Michael S Tsirkin.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
samples/bpf: fix bpf tunnel cleanup
udp6: fix jumbogram reception
ppp: Fix a scheduling-while-atomic bug in del_chan
Revert "net: bcmgenet: Remove init parameter from bcmgenet_mii_config"
virtio_net: fix truesize for mergeable buffers
mv643xx_eth: fix of_irq_to_resource() error check
MAINTAINERS: Add more files to the PHY LIBRARY section
ipv4: fib: Fix NULL pointer deref during fib_sync_down_dev()
net: phy: Correctly process PHY_HALTED in phy_stop_machine()
sunhme: fix up GREG_STAT and GREG_IMASK register offsets
bpf: fix bpf_prog_get_info_by_fd to dump correct xlated_prog_len
tcp: avoid bogus gcc-7 array-bounds warning
net: tc35815: fix spelling mistake: "Intterrupt" -> "Interrupt"
bpf: don't indicate success when copy_from_user fails
udp6: fix socket leak on early demux
net: thunderx: Fix BGX transmit stall due to underflow
Revert "vhost: cache used event for better performance"
team: use a larger struct for mac address
net: check dev->addr_len for dev_set_mac_address()
phy: bcm-ns-usb3: fix MDIO_BUS dependency
...
|
|
I forgot one spot when introducing struct test_obj_val.
Fixes: e859afe1ee0c5 ("lib: test_rhashtable: fix for large entry counts")
Reported by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
During concurrent access testing, threadfunc() concatenated thread ID
and object index to create a unique key like so:
| tdata->objs[i].value = (tdata->id << 16) | i;
This breaks if a user passes an entries parameter of 64k or higher,
since 'i' might use more than 16 bits then. Effectively, this will lead
to duplicate keys in the table.
Fix the problem by introducing a struct holding object and thread ID and
using that as key instead of a single integer type field.
Fixes: f4a3e90ba5739 ("rhashtable-test: extend to test concurrency")
Reported by: Manuel Messner <mm@skelett.io>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
Fixes: df33767d ("uuid: hoist helpers uuid_equal() and uuid_copy() from xfs")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random
Pull random updates from Ted Ts'o:
"Add wait_for_random_bytes() and get_random_*_wait() functions so that
callers can more safely get random bytes if they can block until the
CRNG is initialized.
Also print a warning if get_random_*() is called before the CRNG is
initialized. By default, only one single-line warning will be printed
per boot. If CONFIG_WARN_ALL_UNSEEDED_RANDOM is defined, then a
warning will be printed for each function which tries to get random
bytes before the CRNG is initialized. This can get spammy for certain
architecture types, so it is not enabled by default"
* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
random: reorder READ_ONCE() in get_random_uXX
random: suppress spammy warnings about unseeded randomness
random: warn when kernel uses unseeded randomness
net/route: use get_random_int for random counter
net/neighbor: use get_random_u32 for 32-bit hash random
rhashtable: use get_random_u32 for hash_rnd
ceph: ensure RNG is seeded before using
iscsi: ensure RNG is seeded before use
cifs: use get_random_u32 for 32-bit lock random
random: add get_random_{bytes,u32,u64,int,long,once}_wait family
random: add wait_for_random_bytes() API
|
|
Unfortunately, on some models of some architectures getting a fully
seeded CRNG is extremely difficult, and so this can result in dmesg
getting spammed for a surprisingly long time. This is really bad from
a security perspective, and so architecture maintainers really need to
do what they can to get the CRNG seeded sooner after the system is
booted. However, users can't do anything actionble to address this,
and spamming the kernel messages log will only just annoy people.
For developers who want to work on improving this situation,
CONFIG_WARN_UNSEEDED_RANDOM has been renamed to
CONFIG_WARN_ALL_UNSEEDED_RANDOM. By default the kernel will always
print the first use of unseeded randomness. This way, hopefully the
security obsessed will be happy that there is _some_ indication when
the kernel boots there may be a potential issue with that architecture
or subarchitecture. To see all uses of unseeded randomness,
developers can enable CONFIG_WARN_ALL_UNSEEDED_RANDOM.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
|
|
This adds a new stress test driver for kmod: the kernel module loader.
The new stress test driver, test_kmod, is only enabled as a module right
now. It should be possible to load this as built-in and load tests
early (refer to the force_init_test module parameter), however since a
lot of test can get a system out of memory fast we leave this disabled
for now.
Using a system with 1024 MiB of RAM can *easily* get your kernel OOM
fast with this test driver.
The test_kmod driver exposes API knobs for us to fine tune simple
request_module() and get_fs_type() calls. Since these API calls only
allow each one parameter a test driver for these is rather simple.
Other factors that can help out test driver though are the number of
calls we issue and knowing current limitations of each. This exposes
configuration as much as possible through userspace to be able to build
tests directly from userspace.
Since it allows multiple misc devices its will eventually (once we add a
knob to let us create new devices at will) also be possible to perform
more tests in parallel, provided you have enough memory.
We only enable tests we know work as of right now.
Demo screenshots:
# tools/testing/selftests/kmod/kmod.sh
kmod_test_0001_driver: OK! - loading kmod test
kmod_test_0001_driver: OK! - Return value: 256 (MODULE_NOT_FOUND), expected MODULE_NOT_FOUND
kmod_test_0001_fs: OK! - loading kmod test
kmod_test_0001_fs: OK! - Return value: -22 (-EINVAL), expected -EINVAL
kmod_test_0002_driver: OK! - loading kmod test
kmod_test_0002_driver: OK! - Return value: 256 (MODULE_NOT_FOUND), expected MODULE_NOT_FOUND
kmod_test_0002_fs: OK! - loading kmod test
kmod_test_0002_fs: OK! - Return value: -22 (-EINVAL), expected -EINVAL
kmod_test_0003: OK! - loading kmod test
kmod_test_0003: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0004: OK! - loading kmod test
kmod_test_0004: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0005: OK! - loading kmod test
kmod_test_0005: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0006: OK! - loading kmod test
kmod_test_0006: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0005: OK! - loading kmod test
kmod_test_0005: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0006: OK! - loading kmod test
kmod_test_0006: OK! - Return value: 0 (SUCCESS), expected SUCCESS
XXX: add test restult for 0007
Test completed
You can also request for specific tests:
# tools/testing/selftests/kmod/kmod.sh -t 0001
kmod_test_0001_driver: OK! - loading kmod test
kmod_test_0001_driver: OK! - Return value: 256 (MODULE_NOT_FOUND), expected MODULE_NOT_FOUND
kmod_test_0001_fs: OK! - loading kmod test
kmod_test_0001_fs: OK! - Return value: -22 (-EINVAL), expected -EINVAL
Test completed
Lastly, the current available number of tests:
# tools/testing/selftests/kmod/kmod.sh --help
Usage: tools/testing/selftests/kmod/kmod.sh [ -t <4-number-digit> ]
Valid tests: 0001-0009
0001 - Simple test - 1 thread for empty string
0002 - Simple test - 1 thread for modules/filesystems that do not exist
0003 - Simple test - 1 thread for get_fs_type() only
0004 - Simple test - 2 threads for get_fs_type() only
0005 - multithreaded tests with default setup - request_module() only
0006 - multithreaded tests with default setup - get_fs_type() only
0007 - multithreaded tests with default setup test request_module() and get_fs_type()
0008 - multithreaded - push kmod_concurrent over max_modprobes for request_module()
0009 - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()
The following test cases currently fail, as such they are not currently
enabled by default:
# tools/testing/selftests/kmod/kmod.sh -t 0008
# tools/testing/selftests/kmod/kmod.sh -t 0009
To be sure to run them as intended please unload both of the modules:
o test_module
o xfs
And ensure they are not loaded on your system prior to testing them. If
you use these paritions for your rootfs you can change the default test
driver used for get_fs_type() by exporting it into your environment. For
example of other test defaults you can override refer to kmod.sh
allow_user_defaults().
Behind the scenes this is how we fine tune at a test case prior to
hitting a trigger to run it:
cat /sys/devices/virtual/misc/test_kmod0/config
echo -n "2" > /sys/devices/virtual/misc/test_kmod0/config_test_case
echo -n "ext4" > /sys/devices/virtual/misc/test_kmod0/config_test_fs
echo -n "80" > /sys/devices/virtual/misc/test_kmod0/config_num_threads
cat /sys/devices/virtual/misc/test_kmod0/config
echo -n "1" > /sys/devices/virtual/misc/test_kmod0/config_num_threads
Finally to trigger:
echo -n "1" > /sys/devices/virtual/misc/test_kmod0/trigger_config
The kmod.sh script uses the above constructs to build different test cases.
A bit of interpretation of the current failures follows, first two
premises:
a) When request_module() is used userspace figures out an optimized
version of module order for us. Once it finds the modules it needs, as
per depmod symbol dep map, it will finit_module() the respective
modules which are needed for the original request_module() request.
b) We have an optimization in place whereby if a kernel uses
request_module() on a module already loaded we never bother userspace
as the module already is loaded. This is all handled by kernel/kmod.c.
A few things to consider to help identify root causes of issues:
0) kmod 19 has a broken heuristic for modules being assumed to be
built-in to your kernel and will return 0 even though request_module()
failed. Upgrade to a newer version of kmod.
1) A get_fs_type() call for "xfs" will request_module() for "fs-xfs",
not for "xfs". The optimization in kernel described in b) fails to
catch if we have a lot of consecutive get_fs_type() calls. The reason
is the optimization in place does not look for aliases. This means two
consecutive get_fs_type() calls will bump kmod_concurrent, whereas
request_module() will not.
This one explanation why test case 0009 fails at least once for
get_fs_type().
2) If a module fails to load --- for whatever reason (kmod_concurrent
limit reached, file not yet present due to rootfs switch, out of
memory) we have a period of time during which module request for the
same name either with request_module() or get_fs_type() will *also*
fail to load even if the file for the module is ready.
This explains why *multiple* NULLs are possible on test 0009.
3) finit_module() consumes quite a bit of memory.
4) Filesystems typically also have more dependent modules than other
modules, its important to note though that even though a get_fs_type()
call does not incur additional kmod_concurrent bumps, since userspace
loads dependencies it finds it needs via finit_module_fd(), it *will*
take much more memory to load a module with a lot of dependencies.
Because of 3) and 4) we will easily run into out of memory failures with
certain tests. For instance test 0006 fails on qemu with 1024 MiB of RAM.
It panics a box after reaping all userspace processes and still not
having enough memory to reap.
[arnd@arndb.de: add dependencies for test module]
Link: http://lkml.kernel.org/r/20170630154834.3689272-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20170628223155.26472-3-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michal Marek <mmarek@suse.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The fail-nth file is created with 0666 and the access is permitted if
and only if the task is current.
This file is owned by the currnet user. So we can create it with 0644
and allow the owner to write it. This enables to watch the status of
task->fail_nth from another processes.
[akinobu.mita@gmail.com: don't convert unsigned type value as signed int]
Link: http://lkml.kernel.org/r/1492444483-9239-1-git-send-email-akinobu.mita@gmail.com
[akinobu.mita@gmail.com: avoid unwanted data race to task->fail_nth]
Link: http://lkml.kernel.org/r/1499962492-8931-1-git-send-email-akinobu.mita@gmail.com
Link: http://lkml.kernel.org/r/1491490561-10485-5-git-send-email-akinobu.mita@gmail.com
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
atomic64_inc_not_zero() returns a "truth value" which in C is
traditionally an int. That means callers are likely to expect the
result will fit in an int.
If an implementation returns a "true" value which does not fit in an
int, then there's a possibility that callers will truncate it when they
store it in an int.
In fact this happened in practice, see commit 966d2b04e070
("percpu-refcount: fix reference leak during percpu-atomic transition").
So add a test that the result fits in an int, even when the input
doesn't. This catches the case where an implementation just passes the
non-zero input value out as the result.
Link: http://lkml.kernel.org/r/1499775133-1231-1-git-send-email-mpe@ellerman.id.au
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Douglas Miller <dougmill@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Currently the writeback statistics code uses a percpu counters to hold
various statistics. Furthermore we have 2 families of functions - those
which disable local irq and those which doesn't and whose names begin
with double underscore. However, they both end up calling
__add_wb_stats which in turn calls percpu_counter_add_batch which is
already irq-safe.
Exploiting this fact allows to eliminated the __wb_* functions since
they don't add any further protection than we already have.
Furthermore, refactor the wb_* function to call __add_wb_stat directly
without the irq-disabling dance. This will likely result in better
runtime of code which deals with modifying the stat counters.
While at it also document why percpu_counter_add_batch is in fact
preempt and irq-safe since at least 3 people got confused.
Link: http://lkml.kernel.org/r/1498029937-27293-1-git-send-email-nborisov@suse.com
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time. Unlike glibc,
it covers buffer reads in addition to writes.
GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation. They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks. Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.
This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code. There will likely be issues caught in
regular use at runtime too.
Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:
* Some of the fortified string functions (strncpy, strcat), don't yet
place a limit on reads from the source based on __builtin_object_size of
the source buffer.
* Extending coverage to more string functions like strlcat.
* It should be possible to optionally use __builtin_object_size(x, 1) for
some functions (C strings) to detect intra-object overflows (like
glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
approach to avoid likely compatibility issues.
* The compile-time checks should be made available via a separate config
option which can be enabled by default (or always enabled) once enough
time has passed to get the issues it catches fixed.
Kees said:
"This is great to have. While it was out-of-tree code, it would have
blocked at least CVE-2016-3858 from being exploitable (improper size
argument to strlcpy()). I've sent a number of fixes for
out-of-bounds-reads that this detected upstream already"
[arnd@arndb.de: x86: fix fortified memcpy]
Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Split SOFTLOCKUP_DETECTOR from LOCKUP_DETECTOR, and split
HARDLOCKUP_DETECTOR_PERF from HARDLOCKUP_DETECTOR.
LOCKUP_DETECTOR implies the general boot, sysctl, and programming
interfaces for the lockup detectors.
An architecture that wants to use a hard lockup detector must define
HAVE_HARDLOCKUP_DETECTOR_PERF or HAVE_HARDLOCKUP_DETECTOR_ARCH.
Alternatively an arch can define HAVE_NMI_WATCHDOG, which provides the
minimum arch_touch_nmi_watchdog, and it otherwise does its own thing and
does not implement the LOCKUP_DETECTOR interfaces.
sparc is unusual in that it has started to implement some of the
interfaces, but not fully yet. It should probably be converted to a full
HAVE_HARDLOCKUP_DETECTOR_ARCH.
[npiggin@gmail.com: fix]
Link: http://lkml.kernel.org/r/20170617223522.66c0ad88@roar.ozlabs.ibm.com
Link: http://lkml.kernel.org/r/20170616065715.18390-4-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Tested-by: Babu Moger <babu.moger@oracle.com> [sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Add /proc/self/task/<current-tid>/fail-nth file that allows failing
0-th, 1-st, 2-nd and so on calls systematically.
Excerpt from the added documentation:
"Write to this file of integer N makes N-th call in the current task
fail (N is 0-based). Read from this file returns a single char 'Y' or
'N' that says if the fault setup with a previous write to this file
was injected or not, and disables the fault if it wasn't yet injected.
Note that this file enables all types of faults (slab, futex, etc).
This setting takes precedence over all other generic settings like
probability, interval, times, etc. But per-capability settings (e.g.
fail_futex/ignore-private) take precedence over it. This feature is
intended for systematic testing of faults in a single system call. See
an example below"
Why add a new setting:
1. Existing settings are global rather than per-task.
So parallel testing is not possible.
2. attr->interval is close but it depends on attr->count
which is non reset to 0, so interval does not work as expected.
3. Trying to model this with existing settings requires manipulations
of all of probability, interval, times, space, task-filter and
unexposed count and per-task make-it-fail files.
4. Existing settings are per-failure-type, and the set of failure
types is potentially expanding.
5. make-it-fail can't be changed by unprivileged user and aggressive
stress testing better be done from an unprivileged user.
Similarly, this would require opening the debugfs files to the
unprivileged user, as he would need to reopen at least times file
(not possible to pre-open before dropping privs).
The proposed interface solves all of the above (see the example).
We want to integrate this into syzkaller fuzzer. A prototype has found
10 bugs in kernel in first day of usage:
https://groups.google.com/forum/#!searchin/syzkaller/%22FAULT_INJECTION%22%7Csort:relevance
I've made the current interface work with all types of our sandboxes.
For setuid the secret sauce was prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) to
make /proc entries non-root owned. So I am fine with the current
version of the code.
[akpm@linux-foundation.org: fix build]
Link: http://lkml.kernel.org/r/20170328130128.101773-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Add a few initial respective tests for an array:
o Echoing values separated by spaces works
o Echoing only first elements will set first elements
o Confirm PAGE_SIZE limit still applies even if an array is used
Link: http://lkml.kernel.org/r/20170630224431.17374-7-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Test against a simple proc_douintvec() case. While at it, add a test
against UINT_MAX. Make sure UINT_MAX works, and UINT_MAX+1 will fail
and that negative values are not accepted.
Link: http://lkml.kernel.org/r/20170630224431.17374-6-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Test against a simple proc_dointvec() case. While at it, add a test
against INT_MAX. Make sure INT_MAX works, and INT_MAX+1 will fail.
Also test negative values work.
Link: http://lkml.kernel.org/r/20170630224431.17374-5-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
The existing tools/testing/selftests/sysctl/ tests include two test
cases, but these use existing production kernel sysctl interfaces. We
want to expand test coverage but we can't just be looking for random
safe production values to poke at, that's just insane!
Instead just dedicate a test driver for debugging purposes and port the
existing scripts to use it. This will make it easier for further tests
to be added.
Subsequent patches will extend our test coverage for sysctl.
The stress test driver uses a new license (GPL on Linux, copyleft-next
outside of Linux). Linus was fine with this [0] and later due to Ted's
and Alans's request ironed out an "or" language clause to use [1] which
is already present upstream.
[0] https://lkml.kernel.org/r/CA+55aFyhxcvD+q7tp+-yrSFDKfR0mOHgyEAe=f_94aKLsOu0Og@mail.gmail.com
[1] https://lkml.kernel.org/r/1495234558.7848.122.camel@linux.intel.com
Link: http://lkml.kernel.org/r/20170630224431.17374-2-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There is a slightly faster way (in terms of the number of instructions
being used) to calculate the position of a middle element, preserving
integer overflow safeness.
./scripts/bloat-o-meter lib/bsearch.o.old lib/bsearch.o.new
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-24 (-24)
function old new delta
bsearch 122 98 -24
TEST
INT array of size 100001, elements [0..100000]. gcc 7.1, Os, x86_64.
a) bsearch() of existing key "100001 - 2":
BASE
====
$ perf stat ./a.out
Performance counter stats for './a.out':
619.445196 task-clock:u (msec) # 0.999 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
133 page-faults:u # 0.215 K/sec
1,949,517,279 cycles:u # 3.147 GHz (83.06%)
181,017,938 stalled-cycles-frontend:u # 9.29% frontend cycles idle (83.05%)
82,959,265 stalled-cycles-backend:u # 4.26% backend cycles idle (67.02%)
4,355,706,383 instructions:u # 2.23 insn per cycle
# 0.04 stalled cycles per insn (83.54%)
1,051,539,242 branches:u # 1697.550 M/sec (83.54%)
15,263,381 branch-misses:u # 1.45% of all branches (83.43%)
0.620082548 seconds time elapsed
PATCHED
=======
$ perf stat ./a.out
Performance counter stats for './a.out':
475.097316 task-clock:u (msec) # 0.999 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
135 page-faults:u # 0.284 K/sec
1,487,467,717 cycles:u # 3.131 GHz (82.95%)
186,537,162 stalled-cycles-frontend:u # 12.54% frontend cycles idle (82.93%)
28,797,869 stalled-cycles-backend:u # 1.94% backend cycles idle (67.10%)
3,807,564,203 instructions:u # 2.56 insn per cycle
# 0.05 stalled cycles per insn (83.57%)
1,049,344,291 branches:u # 2208.693 M/sec (83.60%)
5,485 branch-misses:u # 0.00% of all branches (83.58%)
0.475760235 seconds time elapsed
b) bsearch() of un-existing key "100001 + 2":
BASE
====
$ perf stat ./a.out
Performance counter stats for './a.out':
499.244480 task-clock:u (msec) # 0.999 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
132 page-faults:u # 0.264 K/sec
1,571,194,855 cycles:u # 3.147 GHz (83.18%)
13,450,980 stalled-cycles-frontend:u # 0.86% frontend cycles idle (83.18%)
21,256,072 stalled-cycles-backend:u # 1.35% backend cycles idle (66.78%)
4,171,197,909 instructions:u # 2.65 insn per cycle
# 0.01 stalled cycles per insn (83.68%)
1,009,175,281 branches:u # 2021.405 M/sec (83.79%)
3,122 branch-misses:u # 0.00% of all branches (83.37%)
0.499871144 seconds time elapsed
PATCHED
=======
$ perf stat ./a.out
Performance counter stats for './a.out':
399.023499 task-clock:u (msec) # 0.998 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
134 page-faults:u # 0.336 K/sec
1,245,793,991 cycles:u # 3.122 GHz (83.39%)
11,529,273 stalled-cycles-frontend:u # 0.93% frontend cycles idle (83.46%)
12,116,311 stalled-cycles-backend:u # 0.97% backend cycles idle (66.92%)
3,679,710,005 instructions:u # 2.95 insn per cycle
# 0.00 stalled cycles per insn (83.47%)
1,009,792,625 branches:u # 2530.660 M/sec (83.46%)
2,590 branch-misses:u # 0.00% of all branches (83.12%)
0.399733539 seconds time elapsed
Link: http://lkml.kernel.org/r/20170607150457.5905-1-sergey.senozhatsky@gmail.com
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
[thomas@m3y3r.de: v3: fix arch specific implementations]
Link: http://lkml.kernel.org/r/1497890858.12931.7.camel@m3y3r.de
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
bucket_table_alloc() can be currently called with GFP_KERNEL or
GFP_ATOMIC. For the former we basically have an open coded kvzalloc()
while the later only uses kzalloc(). Let's simplify the code a bit by
the dropping the open coded path and replace it with kvzalloc().
Link: http://lkml.kernel.org/r/20170531155145.17111-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
... such that a user can specify visiting all the nodes in the tree
(intersects with the world). This is a nice opposite from the very
basic default query which is a single point.
Link: http://lkml.kernel.org/r/20170518174936.20265-5-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Add a 'max_endpoint' parameter such that users may easily limit the size
of the intervals that are randomly generated.
Link: http://lkml.kernel.org/r/20170518174936.20265-4-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Allows for more flexible debugging.
Link: http://lkml.kernel.org/r/20170518174936.20265-3-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Patch series "lib/interval_tree_test: some debugging improvements".
Here are some patches that update the interval_tree_test module allowing
users to pass finer grained options to run the actual test.
This patch (of 4):
It is a tristate after all, and also serves well for quick debugging.
Link: http://lkml.kernel.org/r/20170518174936.20265-2-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
gcc does generates stupid code sign extending data back and forth. Help
by using "unsigned int".
add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-61 (-61)
function old new delta
_parse_integer 128 123 -5
It _still_ does generate useless MOVSX but I don't know how to delete it:
0000000000000070 <_parse_integer>:
...
a0: 89 c2 mov edx,eax
a2: 83 e8 30 sub eax,0x30
a5: 83 f8 09 cmp eax,0x9
a8: 76 11 jbe bb <_parse_integer+0x4b>
aa: 83 ca 20 or edx,0x20
ad: 0f be c2 ===> movsx eax,dl <===
useless
b0: 8d 50 9f lea edx,[rax-0x61]
b3: 83 fa 05 cmp edx,0x5
Patch also helps on embedded archs which generally only like "int". On
arm "and 0xff" is generated which is waste because all values used in
comparisons are positive.
Link: http://lkml.kernel.org/r/20170514194720.GB32563@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Standard "while (*s)" test is unnecessary because NUL won't pass
valid-digit test anyway. Save one branch per parsed character.
Link: http://lkml.kernel.org/r/20170514193756.GA32563@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
We have eight users calling bitmap_clear for a single bit and seventeen
calling bitmap_set for a single bit. Rather than fix all of them to
call __clear_bit or __set_bit, turn bitmap_clear and bitmap_set into
inline functions and make this special case efficient.
Link: http://lkml.kernel.org/r/20170628153221.11322-3-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Patch series "Bitmap optimisations", v2.
These three bitmap patches use more efficient specialisations when the
compiler can figure out that it's safe to do so. Thanks to Rasmus's
eagle eyes, a nasty bug in v1 was avoided, and I've added a test case
which would have caught it.
This patch (of 4):
This version of the test is actually a no-op; the next patch will enable
it.
Link: http://lkml.kernel.org/r/20170628153221.11322-2-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Pull dmaengine updates from Vinod Koul:
- removal of AVR32 support in dw driver as AVR32 is gone
- new driver for Broadcom stream buffer accelerator (SBA) RAID driver
- add support for Faraday Technology FTDMAC020 in amba-pl08x driver
- IOMMU support in pl330 driver
- updates to bunch of drivers
* tag 'dmaengine-4.13-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (36 commits)
dmaengine: qcom_hidma: correct API violation for submit
dmaengine: zynqmp_dma: Remove max len check in zynqmp_dma_prep_memcpy
dmaengine: tegra-apb: Really fix runtime-pm usage
dmaengine: fsl_raid: make of_device_ids const.
dmaengine: qcom_hidma: allow ACPI/DT parameters to be overridden
dmaengine: fsldma: set BWC, DAHTS and SAHTS values correctly
dmaengine: Kconfig: Simplify the help text for MXS_DMA
dmaengine: pl330: Delete unused functions
dmaengine: Replace WARN_TAINT_ONCE() with pr_warn_once()
dmaengine: Kconfig: Extend the dependency for MXS_DMA
dmaengine: mxs: Use %zu for printing a size_t variable
dmaengine: ste_dma40: Cleanup scatterlist layering violations
dmaengine: imx-dma: cleanup scatterlist layering violations
dmaengine: use proper name for the R-Car SoC
dmaengine: imx-sdma: Fix compilation warning.
dmaengine: imx-sdma: Handle return value of clk_prepare_enable
dmaengine: pl330: Add IOMMU support to slave tranfers
dmaengine: DW DMAC: Handle return value of clk_prepare_enable
dmaengine: pl08x: use GENMASK() to create bitmasks
dmaengine: pl08x: Add support for Faraday Technology FTDMAC020
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull iov_iter hardening from Al Viro:
"This is the iov_iter/uaccess/hardening pile.
For one thing, it trims the inline part of copy_to_user/copy_from_user
to the minimum that *does* need to be inlined - object size checks,
basically. For another, it sanitizes the checks for iov_iter
primitives. There are 4 groups of checks: access_ok(), might_fault(),
object size and KASAN.
- access_ok() had been verified by whoever had set the iov_iter up.
However, that has happened in a function far away, so proving that
there's no path to actual copying bypassing those checks is hard
and proving that iov_iter has not been buggered in the meanwhile is
also not pleasant. So we want those redone in actual
copyin/copyout.
- might_fault() is better off consolidated - we know whether it needs
to be checked as soon as we enter iov_iter primitive and observe
the iov_iter flavour. No need to wait until the copyin/copyout. The
call chains are short enough to make sure we won't miss anything -
in fact, it's more robust that way, since there are cases where we
do e.g. forced fault-in before getting to copyin/copyout. It's not
quite what we need to check (in particular, combination of
iovec-backed and set_fs(KERNEL_DS) is almost certainly a bug, not a
cause to skip checks), but that's for later series. For now let's
keep might_fault().
- KASAN checks belong in copyin/copyout - at the same level where
other iov_iter flavours would've hit them in memcpy().
- object size checks should apply to *all* iov_iter flavours, not
just iovec-backed ones.
There are two groups of primitives - one gets the kernel object
described as pointer + size (copy_to_iter(), etc.) while another gets
it as page + offset + size (copy_page_to_iter(), etc.)
For the first group the checks are best done where we actually have a
chance to find the object size. In other words, those belong in inline
wrappers in uio.h, before calling into iov_iter.c. Same kind as we
have for inlined part of copy_to_user().
For the second group there is no object to look at - offset in page is
just a number, it bears no type information. So we do them in the
common helper called by iov_iter.c primitives of that kind. All it
currently does is checking that we are not trying to access outside of
the compound page; eventually we might want to add some sanity checks
on the page involved.
So the things we need in copyin/copyout part of iov_iter.c do not
quite match anything in uaccess.h (we want no zeroing, we *do* want
access_ok() and KASAN and we want no might_fault() or object size
checks done on that level). OTOH, these needs are simple enough to
provide a couple of helpers (static in iov_iter.c) doing just what we
need..."
* 'uaccess-work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
iov_iter: saner checks on copyin/copyout
iov_iter: sanity checks for copy to/from page primitives
iov_iter/hardening: move object size checks to inlined part
copy_{to,from}_user(): consolidate object size checks
copy_{from,to}_user(): move kasan checks and might_fault() out-of-line
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull Writeback error handling updates from Jeff Layton:
"This pile represents the bulk of the writeback error handling fixes
that I have for this cycle. Some of the earlier patches in this pile
may look trivial but they are prerequisites for later patches in the
series.
The aim of this set is to improve how we track and report writeback
errors to userland. Most applications that care about data integrity
will periodically call fsync/fdatasync/msync to ensure that their
writes have made it to the backing store.
For a very long time, we have tracked writeback errors using two flags
in the address_space: AS_EIO and AS_ENOSPC. Those flags are set when a
writeback error occurs (via mapping_set_error) and are cleared as a
side-effect of filemap_check_errors (as you noted yesterday). This
model really sucks for userland.
Only the first task to call fsync (or msync or fdatasync) will see the
error. Any subsequent task calling fsync on a file will get back 0
(unless another writeback error occurs in the interim). If I have
several tasks writing to a file and calling fsync to ensure that their
writes got stored, then I need to have them coordinate with one
another. That's difficult enough, but in a world of containerized
setups that coordination may even not be possible.
But wait...it gets worse!
The calls to filemap_check_errors can be buried pretty far down in the
call stack, and there are internal callers of filemap_write_and_wait
and the like that also end up clearing those errors. Many of those
callers ignore the error return from that function or return it to
userland at nonsensical times (e.g. truncate() or stat()). If I get
back -EIO on a truncate, there is no reason to think that it was
because some previous writeback failed, and a subsequent fsync() will
(incorrectly) return 0.
This pile aims to do three things:
1) ensure that when a writeback error occurs that that error will be
reported to userland on a subsequent fsync/fdatasync/msync call,
regardless of what internal callers are doing
2) report writeback errors on all file descriptions that were open at
the time that the error occurred. This is a user-visible change,
but I think most applications are written to assume this behavior
anyway. Those that aren't are unlikely to be hurt by it.
3) document what filesystems should do when there is a writeback
error. Today, there is very little consistency between them, and a
lot of cargo-cult copying. We need to make it very clear what
filesystems should do in this situation.
To achieve this, the set adds a new data type (errseq_t) and then
builds new writeback error tracking infrastructure around that. Once
all of that is in place, we change the filesystems to use the new
infrastructure for reporting wb errors to userland.
Note that this is just the initial foray into cleaning up this mess.
There is a lot of work remaining here:
1) convert the rest of the filesystems in a similar fashion. Once the
initial set is in, then I think most other fs' will be fairly
simple to convert. Hopefully most of those can in via individual
filesystem trees.
2) convert internal waiters on writeback to use errseq_t for
detecting errors instead of relying on the AS_* flags. I have some
draft patches for this for ext4, but they are not quite ready for
prime time yet.
This was a discussion topic this year at LSF/MM too. If you're
interested in the gory details, LWN has some good articles about this:
https://lwn.net/Articles/718734/
https://lwn.net/Articles/724307/"
* tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
btrfs: minimal conversion to errseq_t writeback error reporting on fsync
xfs: minimal conversion to errseq_t writeback error reporting
ext4: use errseq_t based error handling for reporting data writeback errors
fs: convert __generic_file_fsync to use errseq_t based reporting
block: convert to errseq_t based writeback error tracking
dax: set errors in mapping when writeback fails
Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors
mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error
fs: new infrastructure for writeback error handling and reporting
lib: add errseq_t type and infrastructure for handling it
mm: don't TestClearPageError in __filemap_fdatawait_range
mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails
jbd2: don't clear and reset errors after waiting on writeback
buffer: set errors in mapping at the time that the error occurs
fs: check for writeback errors after syncing out buffers in generic_file_fsync
buffer: use mapping_set_error instead of setting the flag
mm: fix mapping_set_error call in me_pagecache_dirty
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull DeviceTree updates from Rob Herring:
- vsprintf format specifier %pOF for device_node's. This will enable us
to stop storing the full node names. Conversion of users will happen
next cycle.
- Update documentation to point to DT specification instead of ePAPR.
- Split out graph and property functions to a separate file.
- New of-graph functions for ALSA
- Add vendor prefixes for RISC-V, Linksys, iWave Systems, Roofull,
Itead, and BananaPi.
- Improve dtx_diff utility filename printing.
* tag 'devicetree-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (32 commits)
of: document /sys/firmware/fdt
dt-bindings: Add RISC-V vendor prefix
vsprintf: Add %p extension "%pOF" for device tree
of: find_node_by_full_name rewrite to compare each level
of: use kbasename instead of open coding
dt-bindings: thermal: add file extension to brcm,ns-thermal
of: update ePAPR references to point to Devicetree Specification
scripts/dtc: dtx_diff - Show real file names in diff header
of: detect invalid phandle in overlay
of: be consistent in form of file mode
of: make __of_attach_node() static
of: address.c header comment typo
of: fdt.c header comment typo
of: make of_fdt_is_compatible() static
dt-bindings: display-timing.txt convert non-ascii characters to ascii
Documentation: remove overlay-notes reference to non-existent file
dt-bindings: usb: exynos-usb: Add missing required VDD properties
dt-bindings: Add vendor prefix for Linksys
MAINTAINERS: add device tree ABI documentation file
of: Add vendor prefix for iWave Systems Technologies Pvt. Ltd
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"libnvdimm updates for the latest ACPI and UEFI specifications. This
pull request also includes new 'struct dax_operations' enabling to
undo the abuse of copy_user_nocache() for copy operations to pmem.
The dax work originally missed 4.12 to address concerns raised by Al.
Summary:
- Introduce the _flushcache() family of memory copy helpers and use
them for persistent memory write operations on x86. The
_flushcache() semantic indicates that the cache is either bypassed
for the copy operation (movnt) or any lines dirtied by the copy
operation are written back (clwb, clflushopt, or clflush).
- Extend dax_operations with ->copy_from_iter() and ->flush()
operations. These operations and other infrastructure updates allow
all persistent memory specific dax functionality to be pushed into
libnvdimm and the pmem driver directly. It also allows dax-specific
sysfs attributes to be linked to a host device, for example:
/sys/block/pmem0/dax/write_cache
- Add support for the new NVDIMM platform/firmware mechanisms
introduced in ACPI 6.2 and UEFI 2.7. This support includes the v1.2
namespace label format, extensions to the address-range-scrub
command set, new error injection commands, and a new BTT
(block-translation-table) layout. These updates support inter-OS
and pre-OS compatibility.
- Fix a longstanding memory corruption bug in nfit_test.
- Make the pmem and nvdimm-region 'badblocks' sysfs files poll(2)
capable.
- Miscellaneous fixes and small updates across libnvdimm and the nfit
driver.
Acknowledgements that came after the branch was pushed: commit
6aa734a2f38e ("libnvdimm, region, pmem: fix 'badblocks'
sysfs_get_dirent() reference lifetime") was reviewed by Toshi Kani
<toshi.kani@hpe.com>"
* tag 'libnvdimm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (42 commits)
libnvdimm, namespace: record 'lbasize' for pmem namespaces
acpi/nfit: Issue Start ARS to retrieve existing records
libnvdimm: New ACPI 6.2 DSM functions
acpi, nfit: Show bus_dsm_mask in sysfs
libnvdimm, acpi, nfit: Add bus level dsm mask for pass thru.
acpi, nfit: Enable DSM pass thru for root functions.
libnvdimm: passthru functions clear to send
libnvdimm, btt: convert some info messages to warn/err
libnvdimm, region, pmem: fix 'badblocks' sysfs_get_dirent() reference lifetime
libnvdimm: fix the clear-error check in nsio_rw_bytes
libnvdimm, btt: fix btt_rw_page not returning errors
acpi, nfit: quiet invalid block-aperture-region warnings
libnvdimm, btt: BTT updates for UEFI 2.7 format
acpi, nfit: constify *_attribute_group
libnvdimm, pmem: disable dax flushing when pmem is fronting a volatile region
libnvdimm, pmem, dax: export a cache control attribute
dax: convert to bitmask for flags
dax: remove default copy_from_iter fallback
libnvdimm, nfit: enable support for volatile ranges
libnvdimm, pmem: fix persistence warning
...
|
|
* might_fault() is better checked in caller (and e.g. fault-in + kmap_atomic
codepath also needs might_fault() coverage)
* we have already done object size checks
* we have *NOT* done access_ok() recently enough; we rely upon the
iovec array having passed sanity checks back when it had been created
and not nothing having buggered it since. However, that's very much
non-local, so we'd better recheck that.
So the thing we want does not match anything in uaccess - we need
access_ok + kasan checks + raw copy without any zeroing. Just define
such helpers and use them here.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull user access str* updates from Al Viro:
"uaccess str...() dead code removal"
* 'uaccess.strlen' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
s390 keyboard.c: don't open-code strndup_user()
mips: get rid of unused __strnlen_user()
get rid of unused __strncpy_from_user() instances
kill strlen_user()
|
|
Pull dma-mapping infrastructure from Christoph Hellwig:
"This is the first pull request for the new dma-mapping subsystem
In this new subsystem we'll try to properly maintain all the generic
code related to dma-mapping, and will further consolidate arch code
into common helpers.
This pull request contains:
- removal of the DMA_ERROR_CODE macro, replacing it with calls to
->mapping_error so that the dma_map_ops instances are more self
contained and can be shared across architectures (me)
- removal of the ->set_dma_mask method, which duplicates the
->dma_capable one in terms of functionality, but requires more
duplicate code.
- various updates for the coherent dma pool and related arm code
(Vladimir)
- various smaller cleanups (me)"
* tag 'dma-mapping-4.13' of git://git.infradead.org/users/hch/dma-mapping: (56 commits)
ARM: dma-mapping: Remove traces of NOMMU code
ARM: NOMMU: Set ARM_DMA_MEM_BUFFERABLE for M-class cpus
ARM: NOMMU: Introduce dma operations for noMMU
drivers: dma-mapping: allow dma_common_mmap() for NOMMU
drivers: dma-coherent: Introduce default DMA pool
drivers: dma-coherent: Account dma_pfn_offset when used with device tree
dma: Take into account dma_pfn_offset
dma-mapping: replace dmam_alloc_noncoherent with dmam_alloc_attrs
dma-mapping: remove dmam_free_noncoherent
crypto: qat - avoid an uninitialized variable warning
au1100fb: remove a bogus dma_free_nonconsistent call
MAINTAINERS: add entry for dma mapping helpers
powerpc: merge __dma_set_mask into dma_set_mask
dma-mapping: remove the set_dma_mask method
powerpc/cell: use the dma_supported method for ops switching
powerpc/cell: clean up fixed mapping dma_ops initialization
tile: remove dma_supported and mapping_error methods
xen-swiotlb: remove xen_swiotlb_set_dma_mask
arm: implement ->dma_supported instead of ->set_dma_mask
mips/loongson64: implement ->dma_supported instead of ->set_dma_mask
...
|
