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 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>
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Merge tag 'for-linus-v4.13-2' of 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
An errseq_t is a way of recording errors in one place, and allowing any
number of "subscribers" to tell whether an error has been set again
since a previous time.
It's implemented as an unsigned 32-bit value that is managed with atomic
operations. The low order bits are designated to hold an error code
(max size of MAX_ERRNO). The upper bits are used as a counter.
The API works with consumers sampling an errseq_t value at a particular
point in time. Later, that value can be used to tell whether new errors
have been set since that time.
Note that there is a 1 in 512k risk of collisions here if new errors
are being recorded frequently, since we have so few bits to use as a
counter. To mitigate this, one bit is used as a flag to tell whether the
value has been sampled since a new value was recorded. That allows
us to avoid bumping the counter if no one has sampled it since it
was last bumped.
Later patches will build on this infrastructure to change how writeback
errors are tracked in the kernel.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Here is the "big" char/misc driver patchset for 4.13-rc1.
Lots of stuff in here, a large thunderbolt update, w1 driver header
reorg, the new mux driver subsystem, google firmware driver updates, and
a raft of other smaller things. Full details in the shortlog.
All of these have been in linux-next for a while with the only reported
issue being a merge problem with this tree and the jc-docs tree in the
w1 documentation area. The fix should be obvious for what to do when it
happens, if not, we can send a follow-up patch for it afterward.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc updates from Greg KH:
"Here is the "big" char/misc driver patchset for 4.13-rc1.
Lots of stuff in here, a large thunderbolt update, w1 driver header
reorg, the new mux driver subsystem, google firmware driver updates,
and a raft of other smaller things. Full details in the shortlog.
All of these have been in linux-next for a while with the only
reported issue being a merge problem with this tree and the jc-docs
tree in the w1 documentation area"
* tag 'char-misc-4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (147 commits)
misc: apds990x: Use sysfs_match_string() helper
mei: drop unreachable code in mei_start
mei: validate the message header only in first fragment.
DocBook: w1: Update W1 file locations and names in DocBook
mux: adg792a: always require I2C support
nvmem: rockchip-efuse: add support for rk322x-efuse
nvmem: core: add locking to nvmem_find_cell
nvmem: core: Call put_device() in nvmem_unregister()
nvmem: core: fix leaks on registration errors
nvmem: correct Broadcom OTP controller driver writes
w1: Add subsystem kernel public interface
drivers/fsi: Add module license to core driver
drivers/fsi: Use asynchronous slave mode
drivers/fsi: Add hub master support
drivers/fsi: Add SCOM FSI client device driver
drivers/fsi/gpio: Add tracepoints for GPIO master
drivers/fsi: Add GPIO based FSI master
drivers/fsi: Document FSI master sysfs files in ABI
drivers/fsi: Add error handling for slave
drivers/fsi: Add tracepoints for low-level operations
...
Add a little helper for crc4 calculations. This works 4-bits-at-a-time,
using a simple table approach.
We will need this in the FSI core code, as well as any master
implementations that need to calculate CRCs in software.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Chris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The sparse-based checking for non-RCU accesses to RCU-protected pointers
has been around for a very long time, and it is now the only type of
sparse-based checking that is optional. This commit therefore makes
it unconditional.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Extract the linked list sorting test code into its own source file, to
allow to compile it either to a loadable module, or builtin into the
kernel.
Link: http://lkml.kernel.org/r/1488287219-15832-4-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Gortmaker <paul.gortmaker@windriver.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>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.12:
API:
- Add batch registration for acomp/scomp
- Change acomp testing to non-unique compressed result
- Extend algorithm name limit to 128 bytes
- Require setkey before accept(2) in algif_aead
Algorithms:
- Add support for deflate rfc1950 (zlib)
Drivers:
- Add accelerated crct10dif for powerpc
- Add crc32 in stm32
- Add sha384/sha512 in ccp
- Add 3des/gcm(aes) for v5 devices in ccp
- Add Queue Interface (QI) backend support in caam
- Add new Exynos RNG driver
- Add ThunderX ZIP driver
- Add driver for hardware random generator on MT7623 SoC"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (101 commits)
crypto: stm32 - Fix OF module alias information
crypto: algif_aead - Require setkey before accept(2)
crypto: scomp - add support for deflate rfc1950 (zlib)
crypto: scomp - allow registration of multiple scomps
crypto: ccp - Change ISR handler method for a v5 CCP
crypto: ccp - Change ISR handler method for a v3 CCP
crypto: crypto4xx - rename ce_ring_contol to ce_ring_control
crypto: testmgr - Allow ecb(cipher_null) in FIPS mode
Revert "crypto: arm64/sha - Add constant operand modifier to ASM_EXPORT"
crypto: ccp - Disable interrupts early on unload
crypto: ccp - Use only the relevant interrupt bits
hwrng: mtk - Add driver for hardware random generator on MT7623 SoC
dt-bindings: hwrng: Add Mediatek hardware random generator bindings
crypto: crct10dif-vpmsum - Fix missing preempt_disable()
crypto: testmgr - replace compression known answer test
crypto: acomp - allow registration of multiple acomps
hwrng: n2 - Use devm_kcalloc() in n2rng_probe()
crypto: chcr - Fix error handling related to 'chcr_alloc_shash'
padata: get_next is never NULL
crypto: exynos - Add new Exynos RNG driver
...
The md5_transform function is no longer used any where in the tree,
except for the crypto api's actual implementation of md5, so we can drop
the function from lib and put it as a static function of the crypto
file, where it belongs. There should be no new users of md5_transform,
anyway, since there are more modern ways of doing what it once achieved.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull IDR rewrite from Matthew Wilcox:
"The most significant part of the following is the patch to rewrite the
IDR & IDA to be clients of the radix tree. But there's much more,
including an enhancement of the IDA to be significantly more space
efficient, an IDR & IDA test suite, some improvements to the IDR API
(and driver changes to take advantage of those improvements), several
improvements to the radix tree test suite and RCU annotations.
The IDR & IDA rewrite had a good spin in linux-next and Andrew's tree
for most of the last cycle. Coupled with the IDR test suite, I feel
pretty confident that any remaining bugs are quite hard to hit. 0-day
did a great job of watching my git tree and pointing out problems; as
it hit them, I added new test-cases to be sure not to be caught the
same way twice"
Willy goes on to expand a bit on the IDR rewrite rationale:
"The radix tree and the IDR use very similar data structures.
Merging the two codebases lets us share the memory allocation pools,
and results in a net deletion of 500 lines of code. It also opens up
the possibility of exposing more of the features of the radix tree to
users of the IDR (and I have some interesting patches along those
lines waiting for 4.12)
It also shrinks the size of the 'struct idr' from 40 bytes to 24 which
will shrink a fair few data structures that embed an IDR"
* 'idr-4.11' of git://git.infradead.org/users/willy/linux-dax: (32 commits)
radix tree test suite: Add config option for map shift
idr: Add missing __rcu annotations
radix-tree: Fix __rcu annotations
radix-tree: Add rcu_dereference and rcu_assign_pointer calls
radix tree test suite: Run iteration tests for longer
radix tree test suite: Fix split/join memory leaks
radix tree test suite: Fix leaks in regression2.c
radix tree test suite: Fix leaky tests
radix tree test suite: Enable address sanitizer
radix_tree_iter_resume: Fix out of bounds error
radix-tree: Store a pointer to the root in each node
radix-tree: Chain preallocated nodes through ->parent
radix tree test suite: Dial down verbosity with -v
radix tree test suite: Introduce kmalloc_verbose
idr: Return the deleted entry from idr_remove
radix tree test suite: Build separate binaries for some tests
ida: Use exceptional entries for small IDAs
ida: Move ida_bitmap to a percpu variable
Reimplement IDR and IDA using the radix tree
radix-tree: Add radix_tree_iter_delete
...
Pull locking fixes from Ingo Molnar:
"The main change is the uninlining of large refcount_t APIs, plus a
header dependency fix.
Note that the uninlining allowed us to enable the underflow/overflow
warnings unconditionally and remove the debug Kconfig switch: this
might trigger new warnings in buggy code and turn
crashes/use-after-free bugs into less harmful memory leaks"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/refcounts: Add missing kernel.h header to have UINT_MAX defined
locking/refcounts: Out-of-line everything
Bart Van Assche noted that the ib DMA mapping code was significantly
similar enough to the core DMA mapping code that with a few changes
it was possible to remove the IB DMA mapping code entirely and
switch the RDMA stack to use the core DMA mapping code. This resulted
in a nice set of cleanups, but touched the entire tree. This branch
will be submitted separately to Linus at the end of the merge window
as per normal practice for tree wide changes like this.
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Merge tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma
Pull rdma DMA mapping updates from Doug Ledford:
"Drop IB DMA mapping code and use core DMA code instead.
Bart Van Assche noted that the ib DMA mapping code was significantly
similar enough to the core DMA mapping code that with a few changes it
was possible to remove the IB DMA mapping code entirely and switch the
RDMA stack to use the core DMA mapping code.
This resulted in a nice set of cleanups, but touched the entire tree
and has been kept separate for that reason."
* tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (37 commits)
IB/rxe, IB/rdmavt: Use dma_virt_ops instead of duplicating it
IB/core: Remove ib_device.dma_device
nvme-rdma: Switch from dma_device to dev.parent
RDS: net: Switch from dma_device to dev.parent
IB/srpt: Modify a debug statement
IB/srp: Switch from dma_device to dev.parent
IB/iser: Switch from dma_device to dev.parent
IB/IPoIB: Switch from dma_device to dev.parent
IB/rxe: Switch from dma_device to dev.parent
IB/vmw_pvrdma: Switch from dma_device to dev.parent
IB/usnic: Switch from dma_device to dev.parent
IB/qib: Switch from dma_device to dev.parent
IB/qedr: Switch from dma_device to dev.parent
IB/ocrdma: Switch from dma_device to dev.parent
IB/nes: Remove a superfluous assignment statement
IB/mthca: Switch from dma_device to dev.parent
IB/mlx5: Switch from dma_device to dev.parent
IB/mlx4: Switch from dma_device to dev.parent
IB/i40iw: Remove a superfluous assignment statement
IB/hns: Switch from dma_device to dev.parent
...
Along with the addition made to Kconfig.debug, the prior existing but
permanently disabled test function has been slightly refactored.
Patch has been tested using QEMU 2.1.2 with a .config obtained through
'make defconfig' (x86_64) and manually enabling the option.
[arnd@arndb.de: move sort self-test into a separate file]
Link: http://lkml.kernel.org/r/20170112110657.3123790-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/HE1PR09MB0394B0418D504DCD27167D4FD49B0@HE1PR09MB0394.eurprd09.prod.outlook.com
Signed-off-by: Kostenzer Felix <fkostenzer@live.at>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Extract the glob test code into its own source file, to allow to compile
it either to a loadable module, or builtin into the kernel.
Link: http://lkml.kernel.org/r/1483470276-10517-2-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Extract the crc32 test code into its own source file, to allow to
compile it either to a loadable module, or builtin into the kernel.
Link: http://lkml.kernel.org/r/1483470276-10517-1-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus asked to please make this real C code.
And since size then isn't an issue what so ever anymore, remove the
debug knob and make all WARN()s unconditional.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dwindsor@gmail.com
Cc: elena.reshetova@intel.com
Cc: gregkh@linuxfoundation.org
Cc: ishkamiel@gmail.com
Cc: keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'drm-for-v4.11-less-shouty' of git://people.freedesktop.org/~airlied/linux
Pull drm updates from Dave Airlie:
"This is the main drm pull request for v4.11.
Nothing too major, the tinydrm and mmu-less support should make
writing smaller drivers easier for some of the simpler platforms, and
there are a bunch of documentation updates.
Intel grew displayport MST audio support which is hopefully useful to
people, and FBC is on by default for GEN9+ (so people know where to
look for regressions). AMDGPU has a lot of fixes that would like new
firmware files installed for some GPUs.
Other than that it's pretty scattered all over.
I may have a follow up pull request as I know BenH has a bunch of AST
rework and fixes and I'd like to get those in once they've been tested
by AST, and I've got at least one pull request I'm just trying to get
the author to fix up.
Core:
- drm_mm reworked
- Connector list locking and iterators
- Documentation updates
- Format handling rework
- MMU-less support for fbdev helpers
- drm_crtc_from_index helper
- Core CRC API
- Remove drm_framebuffer_unregister_private
- Debugfs cleanup
- EDID/Infoframe fixes
- Release callback
- Tinydrm support (smaller drivers for simple hw)
panel:
- Add support for some new simple panels
i915:
- FBC by default for gen9+
- Shared dpll cleanups and docs
- GEN8 powerdomain cleanup
- DMC support on GLK
- DP MST audio support
- HuC loading support
- GVT init ordering fixes
- GVT IOMMU workaround fix
amdgpu/radeon:
- Power/clockgating improvements
- Preliminary SR-IOV support
- TTM buffer priority and eviction fixes
- SI DPM quirks removed due to firmware fixes
- Powerplay improvements
- VCE/UVD powergating fixes
- Cleanup SI GFX code to match CI/VI
- Support for > 2 displays on 3/5 crtc asics
- SI headless fixes
nouveau:
- Rework securre boot code in prep for GP10x secure boot
- Channel recovery improvements
- Initial power budget code
- MMU rework preperation
vmwgfx:
- Bunch of fixes and cleanups
exynos:
- Runtime PM support for MIC driver
- Cleanups to use atomic helpers
- UHD Support for TM2/TM2E boards
- Trigger mode fix for Rinato board
etnaviv:
- Shader performance fix
- Command stream validator fixes
- Command buffer suballocator
rockchip:
- CDN DisplayPort support
- IOMMU support for arm64 platform
imx-drm:
- Fix i.MX5 TV encoder probing
- Remove lower fb size limits
msm:
- Support for HW cursor on MDP5 devices
- DSI encoder cleanup
- GPU DT bindings cleanup
sti:
- stih410 cleanups
- Create fbdev at binding
- HQVDP fixes
- Remove stih416 chip functionality
- DVI/HDMI mode selection fixes
- FPS statistic reporting
omapdrm:
- IRQ code cleanup
dwi-hdmi bridge:
- Cleanups and fixes
adv-bridge:
- Updates for nexus
sii8520 bridge:
- Add interlace mode support
- Rework HDMI and lots of fixes
qxl:
- probing/teardown cleanups
ZTE drm:
- HDMI audio via SPDIF interface
- Video Layer overlay plane support
- Add TV encoder output device
atmel-hlcdc:
- Rework fbdev creation logic
tegra:
- OF node fix
fsl-dcu:
- Minor fixes
mali-dp:
- Assorted fixes
sunxi:
- Minor fix"
[ This was the "fixed" pull, that still had build warnings due to people
not even having build tested the result. I'm not a happy camper
I've fixed the things I noticed up in this merge. - Linus ]
* tag 'drm-for-v4.11-less-shouty' of git://people.freedesktop.org/~airlied/linux: (1177 commits)
lib/Kconfig: make PRIME_NUMBERS not user selectable
drm/tinydrm: helpers: Properly fix backlight dependency
drm/tinydrm: mipi-dbi: Fix field width specifier warning
drm/tinydrm: mipi-dbi: Silence: ‘cmd’ may be used uninitialized
drm/sti: fix build warnings in sti_drv.c and sti_vtg.c files
drm/amd/powerplay: fix PSI feature on Polars12
drm/amdgpu: refuse to reserve io mem for split VRAM buffers
drm/ttm: fix use-after-free races in vm fault handling
drm/tinydrm: Add support for Multi-Inno MI0283QT display
dt-bindings: Add Multi-Inno MI0283QT binding
dt-bindings: display/panel: Add common rotation property
of: Add vendor prefix for Multi-Inno
drm/tinydrm: Add MIPI DBI support
drm/tinydrm: Add helper functions
drm: Add DRM support for tiny LCD displays
drm/amd/amdgpu: post card if there is real hw resetting performed
drm/nouveau/tmr: provide backtrace when a timeout is hit
drm/nouveau/pci/g92: Fix rearm
drm/nouveau/drm/therm/fan: add a fallback if no fan control is specified in the vbios
drm/nouveau/hwmon: expose power_max and power_crit
..
Pull networking updates from David Miller:
"Highlights:
1) Support TX_RING in AF_PACKET TPACKET_V3 mode, from Sowmini
Varadhan.
2) Simplify classifier state on sk_buff in order to shrink it a bit.
From Willem de Bruijn.
3) Introduce SIPHASH and it's usage for secure sequence numbers and
syncookies. From Jason A. Donenfeld.
4) Reduce CPU usage for ICMP replies we are going to limit or
suppress, from Jesper Dangaard Brouer.
5) Introduce Shared Memory Communications socket layer, from Ursula
Braun.
6) Add RACK loss detection and allow it to actually trigger fast
recovery instead of just assisting after other algorithms have
triggered it. From Yuchung Cheng.
7) Add xmit_more and BQL support to mvneta driver, from Simon Guinot.
8) skb_cow_data avoidance in esp4 and esp6, from Steffen Klassert.
9) Export MPLS packet stats via netlink, from Robert Shearman.
10) Significantly improve inet port bind conflict handling, especially
when an application is restarted and changes it's setting of
reuseport. From Josef Bacik.
11) Implement TX batching in vhost_net, from Jason Wang.
12) Extend the dummy device so that VF (virtual function) features,
such as configuration, can be more easily tested. From Phil
Sutter.
13) Avoid two atomic ops per page on x86 in bnx2x driver, from Eric
Dumazet.
14) Add new bpf MAP, implementing a longest prefix match trie. From
Daniel Mack.
15) Packet sample offloading support in mlxsw driver, from Yotam Gigi.
16) Add new aquantia driver, from David VomLehn.
17) Add bpf tracepoints, from Daniel Borkmann.
18) Add support for port mirroring to b53 and bcm_sf2 drivers, from
Florian Fainelli.
19) Remove custom busy polling in many drivers, it is done in the core
networking since 4.5 times. From Eric Dumazet.
20) Support XDP adjust_head in virtio_net, from John Fastabend.
21) Fix several major holes in neighbour entry confirmation, from
Julian Anastasov.
22) Add XDP support to bnxt_en driver, from Michael Chan.
23) VXLAN offloads for enic driver, from Govindarajulu Varadarajan.
24) Add IPVTAP driver (IP-VLAN based tap driver) from Sainath Grandhi.
25) Support GRO in IPSEC protocols, from Steffen Klassert"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1764 commits)
Revert "ath10k: Search SMBIOS for OEM board file extension"
net: socket: fix recvmmsg not returning error from sock_error
bnxt_en: use eth_hw_addr_random()
bpf: fix unlocking of jited image when module ronx not set
arch: add ARCH_HAS_SET_MEMORY config
net: napi_watchdog() can use napi_schedule_irqoff()
tcp: Revert "tcp: tcp_probe: use spin_lock_bh()"
net/hsr: use eth_hw_addr_random()
net: mvpp2: enable building on 64-bit platforms
net: mvpp2: switch to build_skb() in the RX path
net: mvpp2: simplify MVPP2_PRS_RI_* definitions
net: mvpp2: fix indentation of MVPP2_EXT_GLOBAL_CTRL_DEFAULT
net: mvpp2: remove unused register definitions
net: mvpp2: simplify mvpp2_bm_bufs_add()
net: mvpp2: drop useless fields in mvpp2_bm_pool and related code
net: mvpp2: remove unused 'tx_skb' field of 'struct mvpp2_tx_queue'
net: mvpp2: release reference to txq_cpu[] entry after unmapping
net: mvpp2: handle too large value in mvpp2_rx_time_coal_set()
net: mvpp2: handle too large value handling in mvpp2_rx_pkts_coal_set()
net: mvpp2: remove useless arguments in mvpp2_rx_{pkts, time}_coal_set
...
Where we use the radix tree iteration macros, we need to annotate 'slot'
with __rcu. Make sure we don't forget any new places in the future with
the same CFLAGS check used for radix-tree.c.
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Many places were missing __rcu annotations. A few places needed a few
lines of explanation about why it was safe to not use RCU accessors.
Add a custom CFLAGS setting to the Makefile to ensure that new patches
don't miss RCU annotations.
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
This introduces a infrastructure for management of linear priority
areas. Priority order in an array matters, however order of items inside
a priority group does not matter.
As an initial implementation, L-sort algorithm is used. It is quite
trivial. More advanced algorithm called P-sort will be introduced as a
follow-up. The infrastructure is prepared for other algos.
Alongside this, a testing module is introduced as well.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The "half md4" transform should not be used by any new code. And
fortunately, it's only used now by ext4. Since ext4 supports several
hashing methods, at some point it might be desirable to move to
something like SipHash. As an intermediate step, remove half md4 from
cryptohash.h and lib, and make it just a local function in ext4's
hash.c. There's precedent for doing this; the other function ext can use
for its hashes -- TEA -- is also implemented in the same place. Also, by
being a local function, this might allow gcc to perform some additional
optimizations.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Several RDMA drivers (hfi1, qib and rxe) expect that ib_sge.addr
is a virtual address. Provide DMA mapping operations that are
suitable for these drivers.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Reduce the kernel size by only building dma_noop_ops for those
architectures that actually use it. This was suggested by
Christoph Hellwig.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>
SipHash is a 64-bit keyed hash function that is actually a
cryptographically secure PRF, like HMAC. Except SipHash is super fast,
and is meant to be used as a hashtable keyed lookup function, or as a
general PRF for short input use cases, such as sequence numbers or RNG
chaining.
For the first usage:
There are a variety of attacks known as "hashtable poisoning" in which an
attacker forms some data such that the hash of that data will be the
same, and then preceeds to fill up all entries of a hashbucket. This is
a realistic and well-known denial-of-service vector. Currently
hashtables use jhash, which is fast but not secure, and some kind of
rotating key scheme (or none at all, which isn't good). SipHash is meant
as a replacement for jhash in these cases.
There are a modicum of places in the kernel that are vulnerable to
hashtable poisoning attacks, either via userspace vectors or network
vectors, and there's not a reliable mechanism inside the kernel at the
moment to fix it. The first step toward fixing these issues is actually
getting a secure primitive into the kernel for developers to use. Then
we can, bit by bit, port things over to it as deemed appropriate.
While SipHash is extremely fast for a cryptographically secure function,
it is likely a bit slower than the insecure jhash, and so replacements
will be evaluated on a case-by-case basis based on whether or not the
difference in speed is negligible and whether or not the current jhash usage
poses a real security risk.
For the second usage:
A few places in the kernel are using MD5 or SHA1 for creating secure
sequence numbers, syn cookies, port numbers, or fast random numbers.
SipHash is a faster and more fitting, and more secure replacement for MD5
in those situations. Replacing MD5 and SHA1 with SipHash for these uses is
obvious and straight-forward, and so is submitted along with this patch
series. There shouldn't be much of a debate over its efficacy.
Dozens of languages are already using this internally for their hash
tables and PRFs. Some of the BSDs already use this in their kernels.
SipHash is a widely known high-speed solution to a widely known set of
problems, and it's time we catch-up.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
First -misc pull for 4.11:
- drm_mm rework + lots of selftests (Chris Wilson)
- new connector_list locking+iterators
- plenty of kerneldoc updates
- format handling rework from Ville
- atomic helper changes from Maarten for better plane corner-case handling
in drivers, plus the i915 legacy cursor patch that needs this
- bridge cleanup from Laurent
- plus plenty of small stuff all over
- also contains a merge of the 4.10 docs tree so that we could apply the
dma-buf kerneldoc patches
It's a lot more than usual, but due to the merge window blackout it also
covers about 4 weeks, so all in line again on a per-week basis. The more
annoying part with no pull request for 4 weeks is managing cross-tree
work. The -intel pull request I'll follow up with does conflict quite a
bit with -misc here. Longer-term (if drm-misc keeps growing) a
drm-next-queued to accept pull request for the next merge window during
this time might be useful.
I'd also like to backmerge -rc2+this into drm-intel next week, we have
quite a pile of patches waiting for the stuff in here.
* tag 'drm-misc-next-2016-12-30' of git://anongit.freedesktop.org/git/drm-misc: (126 commits)
drm: Add kerneldoc markup for new @scan parameters in drm_mm
drm/mm: Document locking rules
drm: Use drm_mm_insert_node_in_range_generic() for everyone
drm: Apply range restriction after color adjustment when allocation
drm: Wrap drm_mm_node.hole_follows
drm: Apply tight eviction scanning to color_adjust
drm: Simplify drm_mm scan-list manipulation
drm: Optimise power-of-two alignments in drm_mm_scan_add_block()
drm: Compute tight evictions for drm_mm_scan
drm: Fix application of color vs range restriction when scanning drm_mm
drm: Unconditionally do the range check in drm_mm_scan_add_block()
drm: Rename prev_node to hole in drm_mm_scan_add_block()
drm: Fix O= out-of-tree builds for selftests
drm: Extract struct drm_mm_scan from struct drm_mm
drm: Add asserts to catch overflow in drm_mm_init() and drm_mm_init_scan()
drm: Simplify drm_mm_clean()
drm: Detect overflow in drm_mm_reserve_node()
drm: Fix kerneldoc for drm_mm_scan_remove_block()
drm: Promote drm_mm alignment to u64
drm: kselftest for drm_mm and restricted color eviction
...
Prime numbers are interesting for testing components that use multiplies
and divides, such as testing DRM's struct drm_mm alignment computations.
v2: Move to lib/, add selftest
v3: Fix initial constants (exclude 0/1 from being primes)
v4: More RCU markup to keep 0day/sparse happy
v5: Fix RCU unwind on module exit, add to kselftests
v6: Tidy computation of bitmap size
v7: for_each_prime_number_from()
v8: Compose small-primes using BIT() for easier verification
v9: Move rcu dance entirely into callers.
v10: Improve quote for Betrand's Postulate (aka Chebyshev's theorem)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222144514.3911-1-chris@chris-wilson.co.uk
hotcpu_notifier(), cpu_notifier(), __hotcpu_notifier(), __cpu_notifier(),
register_hotcpu_notifier(), register_cpu_notifier(),
__register_hotcpu_notifier(), __register_cpu_notifier(),
unregister_hotcpu_notifier(), unregister_cpu_notifier(),
__unregister_hotcpu_notifier(), __unregister_cpu_notifier()
are unused now. Remove them and all related code.
Remove also the now pointless cpu notifier error injection mechanism. The
states can be executed step by step and error rollback is the same as cpu
down, so any state transition can be tested w/o requiring the notifier
error injection.
Some CPU hotplug states are kept as they are (ab)used for hotplug state
tracking.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161221192112.005642358@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There's no point in collecting coverage from lib/stackdepot.c, as it is
not a function of syscall inputs. Disabling kcov instrumentation for that
file will reduce the coverage noise level.
Link: http://lkml.kernel.org/r/1474640972-104131-1-git-send-email-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull block layer updates from Jens Axboe:
"This is the main pull request for block layer changes in 4.9.
As mentioned at the last merge window, I've changed things up and now
do just one branch for core block layer changes, and driver changes.
This avoids dependencies between the two branches. Outside of this
main pull request, there are two topical branches coming as well.
This pull request contains:
- A set of fixes, and a conversion to blk-mq, of nbd. From Josef.
- Set of fixes and updates for lightnvm from Matias, Simon, and Arnd.
Followup dependency fix from Geert.
- General fixes from Bart, Baoyou, Guoqing, and Linus W.
- CFQ async write starvation fix from Glauber.
- Add supprot for delayed kick of the requeue list, from Mike.
- Pull out the scalable bitmap code from blk-mq-tag.c and make it
generally available under the name of sbitmap. Only blk-mq-tag uses
it for now, but the blk-mq scheduling bits will use it as well.
From Omar.
- bdev thaw error progagation from Pierre.
- Improve the blk polling statistics, and allow the user to clear
them. From Stephen.
- Set of minor cleanups from Christoph in block/blk-mq.
- Set of cleanups and optimizations from me for block/blk-mq.
- Various nvme/nvmet/nvmeof fixes from the various folks"
* 'for-4.9/block' of git://git.kernel.dk/linux-block: (54 commits)
fs/block_dev.c: return the right error in thaw_bdev()
nvme: Pass pointers, not dma addresses, to nvme_get/set_features()
nvme/scsi: Remove power management support
nvmet: Make dsm number of ranges zero based
nvmet: Use direct IO for writes
admin-cmd: Added smart-log command support.
nvme-fabrics: Add host_traddr options field to host infrastructure
nvme-fabrics: revise host transport option descriptions
nvme-fabrics: rework nvmf_get_address() for variable options
nbd: use BLK_MQ_F_BLOCKING
blkcg: Annotate blkg_hint correctly
cfq: fix starvation of asynchronous writes
blk-mq: add flag for drivers wanting blocking ->queue_rq()
blk-mq: remove non-blocking pass in blk_mq_map_request
blk-mq: get rid of manual run of queue with __blk_mq_run_hw_queue()
block: export bio_free_pages to other modules
lightnvm: propagate device_add() error code
lightnvm: expose device geometry through sysfs
lightnvm: control life of nvm_dev in driver
blk-mq: register device instead of disk
...
This commit introduces a generic library to estimate either the min or
max value of a time-varying variable over a recent time window. This
is code originally from Kathleen Nichols. The current form of the code
is from Van Jacobson.
A single struct minmax_sample will track the estimated windowed-max
value of the series if you call minmax_running_max() or the estimated
windowed-min value of the series if you call minmax_running_min().
Nearly equivalent code is already in place for minimum RTT estimation
in the TCP stack. This commit extracts that code and generalizes it to
handle both min and max. Moving the code here reduces the footprint
and complexity of the TCP code base and makes the filter generally
available for other parts of the codebase, including an upcoming TCP
congestion control module.
This library works well for time series where the measurements are
smoothly increasing or decreasing.
Signed-off-by: Van Jacobson <vanj@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a generally useful data structure, so make it available to
anyone else who might want to use it. It's also a nice cleanup
separating the allocation logic from the rest of the tag handling logic.
The code is behind a new Kconfig option, CONFIG_SBITMAP, which is only
selected by CONFIG_BLOCK for now.
This should be a complete noop functionality-wise.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
There are three usercopy warnings which are currently being silenced for
gcc 4.6 and newer:
1) "copy_from_user() buffer size is too small" compile warning/error
This is a static warning which happens when object size and copy size
are both const, and copy size > object size. I didn't see any false
positives for this one. So the function warning attribute seems to
be working fine here.
Note this scenario is always a bug and so I think it should be
changed to *always* be an error, regardless of
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS.
2) "copy_from_user() buffer size is not provably correct" compile warning
This is another static warning which happens when I enable
__compiletime_object_size() for new compilers (and
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS). It happens when object size
is const, but copy size is *not*. In this case there's no way to
compare the two at build time, so it gives the warning. (Note the
warning is a byproduct of the fact that gcc has no way of knowing
whether the overflow function will be called, so the call isn't dead
code and the warning attribute is activated.)
So this warning seems to only indicate "this is an unusual pattern,
maybe you should check it out" rather than "this is a bug".
I get 102(!) of these warnings with allyesconfig and the
__compiletime_object_size() gcc check removed. I don't know if there
are any real bugs hiding in there, but from looking at a small
sample, I didn't see any. According to Kees, it does sometimes find
real bugs. But the false positive rate seems high.
3) "Buffer overflow detected" runtime warning
This is a runtime warning where object size is const, and copy size >
object size.
All three warnings (both static and runtime) were completely disabled
for gcc 4.6 with the following commit:
2fb0815c9e ("gcc4: disable __compiletime_object_size for GCC 4.6+")
That commit mistakenly assumed that the false positives were caused by a
gcc bug in __compiletime_object_size(). But in fact,
__compiletime_object_size() seems to be working fine. The false
positives were instead triggered by #2 above. (Though I don't have an
explanation for why the warnings supposedly only started showing up in
gcc 4.6.)
So remove warning #2 to get rid of all the false positives, and re-enable
warnings #1 and #3 by reverting the above commit.
Furthermore, since #1 is a real bug which is detected at compile time,
upgrade it to always be an error.
Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer
needed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
important is the use of a ChaCha20-based CRNG for /dev/urandom, which
is faster, more efficient, and easier to make scalable for
silly/abusive userspace programs that want to read from /dev/urandom
in a tight loop on NUMA systems.
This set of patches also improves entropy gathering on VM's running on
Microsoft Azure, and will take advantage of a hw random number
generator (if present) to initialize the /dev/urandom pool.
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Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random
Pull random driver updates from Ted Ts'o:
"A number of improvements for the /dev/random driver; the most
important is the use of a ChaCha20-based CRNG for /dev/urandom, which
is faster, more efficient, and easier to make scalable for
silly/abusive userspace programs that want to read from /dev/urandom
in a tight loop on NUMA systems.
This set of patches also improves entropy gathering on VM's running on
Microsoft Azure, and will take advantage of a hw random number
generator (if present) to initialize the /dev/urandom pool"
(It turns out that the random tree hadn't been in linux-next this time
around, because it had been dropped earlier as being too quiet. Oh
well).
* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
random: strengthen input validation for RNDADDTOENTCNT
random: add backtracking protection to the CRNG
random: make /dev/urandom scalable for silly userspace programs
random: replace non-blocking pool with a Chacha20-based CRNG
random: properly align get_random_int_hash
random: add interrupt callback to VMBus IRQ handler
random: print a warning for the first ten uninitialized random users
random: initialize the non-blocking pool via add_hwgenerator_randomness()
People complained about ARCH_HWEIGHT_CFLAGS and how it throws a wrench
into kcov, lto, etc, experimentations.
Add asm versions for __sw_hweight{32,64}() and do explicit saving and
restoring of clobbered registers. This gets rid of the special calling
convention. We get to call those functions on !X86_FEATURE_POPCNT CPUs.
We still need to hardcode POPCNT and register operands as some old gas
versions which we support, do not know about POPCNT.
Btw, remove redundant REX prefix from 32-bit POPCNT because alternatives
can do padding now.
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1464605787-20603-1-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It appears that somehow I missed a test of the latest UUID rework which
landed in the kernel. Present a small test module to avoid such cases
in the future.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull string hash improvements from George Spelvin:
"This series does several related things:
- Makes the dcache hash (fs/namei.c) useful for general kernel use.
(Thanks to Bruce for noticing the zero-length corner case)
- Converts the string hashes in <linux/sunrpc/svcauth.h> to use the
above.
- Avoids 64-bit multiplies in hash_64() on 32-bit platforms. Two
32-bit multiplies will do well enough.
- Rids the world of the bad hash multipliers in hash_32.
This finishes the job started in commit 689de1d6ca ("Minimal
fix-up of bad hashing behavior of hash_64()")
The vast majority of Linux architectures have hardware support for
32x32-bit multiply and so derive no benefit from "simplified"
multipliers.
The few processors that do not (68000, h8/300 and some models of
Microblaze) have arch-specific implementations added. Those
patches are last in the series.
- Overhauls the dcache hash mixing.
The patch in commit 0fed3ac866 ("namei: Improve hash mixing if
CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion.
Replaced with a much more careful design that's simultaneously
faster and better. (My own invention, as there was noting suitable
in the literature I could find. Comments welcome!)
- Modify the hash_name() loop to skip the initial HASH_MIX(). This
would let us salt the hash if we ever wanted to.
- Sort out partial_name_hash().
The hash function is declared as using a long state, even though
it's truncated to 32 bits at the end and the extra internal state
contributes nothing to the result. And some callers do odd things:
- fs/hfs/string.c only allocates 32 bits of state
- fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes
- Modify bytemask_from_count to handle inputs of 1..sizeof(long)
rather than 0..sizeof(long)-1. This would simplify users other
than full_name_hash"
Special thanks to Bruce Fields for testing and finding bugs in v1. (I
learned some humbling lessons about "obviously correct" code.)
On the arch-specific front, the m68k assembly has been tested in a
standalone test harness, I've been in contact with the Microblaze
maintainers who mostly don't care, as the hardware multiplier is never
omitted in real-world applications, and I haven't heard anything from
the H8/300 world"
* 'hash' of git://ftp.sciencehorizons.net/linux:
h8300: Add <asm/hash.h>
microblaze: Add <asm/hash.h>
m68k: Add <asm/hash.h>
<linux/hash.h>: Add support for architecture-specific functions
fs/namei.c: Improve dcache hash function
Eliminate bad hash multipliers from hash_32() and hash_64()
Change hash_64() return value to 32 bits
<linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string()
fs/namei.c: Add hashlen_string() function
Pull out string hash to <linux/stringhash.h>
This is just the infrastructure; there are no users yet.
This is modelled on CONFIG_ARCH_RANDOM; a CONFIG_ symbol declares
the existence of <asm/hash.h>.
That file may define its own versions of various functions, and define
HAVE_* symbols (no CONFIG_ prefix!) to suppress the generic ones.
Included is a self-test (in lib/test_hash.c) that verifies the basics.
It is NOT in general required that the arch-specific functions compute
the same thing as the generic, but if a HAVE_* symbol is defined with
the value 1, then equality is tested.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Philippe De Muyter <phdm@macq.eu>
Cc: linux-m68k@lists.linux-m68k.org
Cc: Alistair Francis <alistai@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: uclinux-h8-devel@lists.sourceforge.jp
Lots of code does
node = next_node(node, XXX);
if (node == MAX_NUMNODES)
node = first_node(XXX);
so create next_node_in() to do this and use it in various places.
[mhocko@suse.com: use next_node_in() helper]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Hui Zhu <zhuhui@xiaomi.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch includes the usual quota of driver updates (bnx2fc, mp3sas,
hpsa, ncr5380, lpfc, hisi_sas, snic, aacraid, megaraid_sas) there's
also a multiqueue update for scsi_debug, assorted bug fixes and a few
other minor updates (refactor of scsi_sg_pools into generic code, alua
and VPD updates, and struct timeval conversions).
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"First round of SCSI updates for the 4.6+ merge window.
This batch includes the usual quota of driver updates (bnx2fc, mp3sas,
hpsa, ncr5380, lpfc, hisi_sas, snic, aacraid, megaraid_sas). There's
also a multiqueue update for scsi_debug, assorted bug fixes and a few
other minor updates (refactor of scsi_sg_pools into generic code, alua
and VPD updates, and struct timeval conversions)"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (138 commits)
mpt3sas: Used "synchronize_irq()"API to synchronize timed-out IO & TMs
mpt3sas: Set maximum transfer length per IO to 4MB for VDs
mpt3sas: Updating mpt3sas driver version to 13.100.00.00
mpt3sas: Fix initial Reference tag field for 4K PI drives.
mpt3sas: Handle active cable exception event
mpt3sas: Update MPI header to 2.00.42
Revert "lpfc: Delete unnecessary checks before the function call mempool_destroy"
eata_pio: missing break statement
hpsa: Fix type ZBC conditional checks
scsi_lib: Decode T10 vendor IDs
scsi_dh_alua: do not fail for unknown VPD identification
scsi_debug: use locally assigned naa
scsi_debug: uuid for lu name
scsi_debug: vpd and mode page work
scsi_debug: add multiple queue support
bfa: fix bfa_fcb_itnim_alloc() error handling
megaraid_sas: Downgrade two success messages to info
cxlflash: Fix to resolve dead-lock during EEH recovery
scsi_debug: rework resp_report_luns
scsi_debug: use pdt constants
...
Now it's ready to move the mempool based SG chained allocator code from
SCSI driver to lib/sg_pool.c, which will be compiled only based on a Kconfig
symbol CONFIG_SG_POOL.
SCSI selects CONFIG_SG_POOL.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
By accident I stumbled across code that is no longer used. According
to git grep, the global functions in lib/proportions.c are not used
anywhere. This patch removes the old, unused code.
Peter Zijlstra further commented:
"Ah indeed, that got replaced with the flex proportion code a while back."
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4265b49bed713fbe3faaf8c05da0e1792f09c0b3.1459432020.git.rcochran@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implement the stack depot and provide CONFIG_STACKDEPOT. Stack depot
will allow KASAN store allocation/deallocation stack traces for memory
chunks. The stack traces are stored in a hash table and referenced by
handles which reside in the kasan_alloc_meta and kasan_free_meta
structures in the allocated memory chunks.
IRQ stack traces are cut below the IRQ entry point to avoid unnecessary
duplication.
Right now stackdepot support is only enabled in SLAB allocator. Once
KASAN features in SLAB are on par with those in SLUB we can switch SLUB
to stackdepot as well, thus removing the dependency on SLUB stack
bookkeeping, which wastes a lot of memory.
This patch is based on the "mm: kasan: stack depots" patch originally
prepared by Dmitry Chernenkov.
Joonsoo has said that he plans to reuse the stackdepot code for the
mm/page_owner.c debugging facility.
[akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t]
[aryabinin@virtuozzo.com: comment style fixes]
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing). Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system. A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/). However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.
kcov does not aim to collect as much coverage as possible. It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g. scheduler, locking).
Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes. Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch). I've
dropped the second mode for simplicity.
This patch adds the necessary support on kernel side. The complimentary
compiler support was added in gcc revision 231296.
We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:
https://github.com/google/syzkaller/wiki/Found-Bugs
We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation". For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.
Why not gcov. Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat. A
typical coverage can be just a dozen of basic blocks (e.g. an invalid
input). In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M). Cost of
kcov depends only on number of executed basic blocks/edges. On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.
kcov exposes kernel PCs and control flow to user-space which is
insecure. But debugfs should not be mapped as user accessible.
Based on a patch by Quentin Casasnovas.
[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: David Drysdale <drysdale@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds basic polling support for vhost.
Reworks virtio to optionally use DMA API, fixing it on Xen.
Balloon stats gained a new entry.
Using the new napi_alloc_skb speeds up virtio net.
virtio blk stats can now be read while another VCPU
us busy inflating or deflating the balloon.
Plus misc cleanups in various places.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio/vhost updates from Michael Tsirkin:
"New features, performance improvements, cleanups:
- basic polling support for vhost
- rework virtio to optionally use DMA API, fixing it on Xen
- balloon stats gained a new entry
- using the new napi_alloc_skb speeds up virtio net
- virtio blk stats can now be read while another VCPU is busy
inflating or deflating the balloon
plus misc cleanups in various places"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_net: replace netdev_alloc_skb_ip_align() with napi_alloc_skb()
vhost_net: basic polling support
vhost: introduce vhost_vq_avail_empty()
vhost: introduce vhost_has_work()
virtio_balloon: Allow to resize and update the balloon stats in parallel
virtio_balloon: Use a workqueue instead of "vballoon" kthread
virtio/s390: size of SET_IND payload
virtio/s390: use dev_to_virtio
vhost: rename vhost_init_used()
vhost: rename cross-endian helpers
virtio_blk: VIRTIO_BLK_F_WCE->VIRTIO_BLK_F_FLUSH
vring: Use the DMA API on Xen
virtio_pci: Use the DMA API if enabled
virtio_mmio: Use the DMA API if enabled
virtio: Add improved queue allocation API
virtio_ring: Support DMA APIs
vring: Introduce vring_use_dma_api()
s390/dma: Allow per device dma ops
alpha/dma: use common noop dma ops
dma: Provide simple noop dma ops
We are going to require dma_ops for several common drivers, even for
systems that do have an identity mapping. Lets provide some minimal
no-op dma_ops that can be used for that purpose.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
