The declaration for swsusp_arch_resume() marks it as 'asmlinkage',
but the definition in x86-32 does not, and it fails to include
the header with the declaration. This leads to a warning when
building with link-time-optimizations:
kernel/power/power.h:108:23: error: type of 'swsusp_arch_resume' does not match original declaration [-Werror=lto-type-mismatch]
extern asmlinkage int swsusp_arch_resume(void);
^
arch/x86/power/hibernate_32.c:148:0: note: 'swsusp_arch_resume' was previously declared here
int swsusp_arch_resume(void)
This moves the declaration into a globally visible header file
and fixes up both x86 definitions to match it.
Johan Hovold [Wed, 31 Jan 2018 05:59:21 +0000 (16:59 +1100)]
ASoC: mt8173-rt5650: fix child-node lookup
This driver used the wrong OF-helper when looking up the optional
capture-codec child node during probe. Instead of searching just
children of the sound node, a tree-wide depth-first search starting at
the unrelated platform node was done. Not only could this end up
matching an unrelated node or no node at all; the platform node could
also be prematurely freed since of_find_node_by_name() drops a reference
to its first argument. This particular pattern has been observed leading
to crashes after probe deferrals in other drivers.
Fix this by dropping the broken call to of_find_node_by_name() and
keeping only the second, correct lookup using of_get_child_by_name()
while taking care not to bail out if the optional node is missing.
Note that this also addresses two capture-codec node-reference leaks
(one for each of the original helper calls).
Compile tested only.
Fixes: d349caeb0510 ("ASoC: mediatek: Add second I2S on mt8173-rt5650 machine driver") Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Mark Brown <[email protected]>
KaiChieh Chuang [Mon, 5 Feb 2018 05:00:00 +0000 (13:00 +0800)]
ASoC: dapm: fix debugfs read using path->connected
This fix a bug in dapm_widget_power_read_file(),
where it may sent opposite order of source/sink widget
into the p->connected().
for example,
static int connected_check(source, sink);
{"w_sink", NULL, "w_source", connected_check}
the dapm_widget_power_read_file() will query p->connected()
in following case
p->conneted("w_source", "w_sink")
p->conneted("w_sink", "w_source")
we should avoid the last case, since it's the wrong order (source/sink)
as declared in snd_soc_dapm_route.
Ulf Hansson [Tue, 23 Jan 2018 20:43:08 +0000 (21:43 +0100)]
PM / domains: Fix up domain-idle-states OF parsing
Commit b539cc82d493 (PM / Domains: Ignore domain-idle-states that are
not compatible), made it possible to ignore non-compatible
domain-idle-states OF nodes. However, in case that happens while doing
the OF parsing, the number of elements in the allocated array would
exceed the numbers actually needed, thus wasting memory.
Fix this by pre-iterating the genpd OF node and counting the number of
compatible domain-idle-states nodes, before doing the allocation. While
doing this, it makes sense to rework the code a bit to avoid open coding,
of parts responsible for the OF node iteration.
Let's also take the opportunity to clarify the function header for
of_genpd_parse_idle_states(), about what is being returned in case of
errors.
Fixes: b539cc82d493 (PM / Domains: Ignore domain-idle-states that are not compatible) Signed-off-by: Ulf Hansson <[email protected]> Reviewed-by: Lina Iyer <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
Felix Fietkau [Wed, 7 Feb 2018 08:49:02 +0000 (09:49 +0100)]
netfilter: nf_flow_offload: fix use-after-free and a resource leak
flow_offload_del frees the flow, so all associated resource must be
freed before.
Since the ct entry in struct flow_offload_entry was allocated by
flow_offload_alloc, it should be freed by flow_offload_free to take care
of the error handling path when flow_offload_add fails.
While at it, make flow_offload_del static, since it should never be
called directly, only from the gc step
Prarit Bhargava [Thu, 18 Jan 2018 15:09:51 +0000 (10:09 -0500)]
ACPI: SPCR: Make SPCR available to x86
SPCR is currently only enabled or ARM64 and x86 can use SPCR to setup
an early console.
General fixes include updating Documentation & Kconfig (for x86),
updating comments, and changing parse_spcr() to acpi_parse_spcr(),
and earlycon_init_is_deferred to earlycon_acpi_spcr_enable to be
more descriptive.
On x86, many systems have a valid SPCR table but the table version is
not 2 so the table version check must be a warning.
On ARM64 when the kernel parameter earlycon is used both the early console
and console are enabled. On x86, only the earlycon should be enabled by
by default. Modify acpi_parse_spcr() to allow options for initializing
the early console and console separately.
ACPI / CPPC: Use 64-bit arithmetic instead of 32-bit
Add suffix ULL to constant 500 in order to give the compiler complete
information about the proper arithmetic to use. Notice that this
constant is used in a context that expects an expression of type
u64 (64 bits, unsigned).
The expression NUM_RETRIES * cppc_ss->latency at line 578, which at
preprocessing time translates to 500 * cppc_ss->latency is currently
being evaluated using 32-bit arithmetic.
Shunyong Yang [Tue, 6 Feb 2018 06:37:12 +0000 (14:37 +0800)]
ACPI / tables: Add IORT to injectable table list
Loading IORT table from initrd can be used to fix severe firmware
IORT defects temporarily before platform/BIOS vendor releases an
upgraded BIOS binary.
Moreover, it is very powerful to debug SMMU node/device probe, MSI
allocation, stream id translation and IORT table from firmware.
It is also very useful to enable SMMU and devices behind SMMU before
firmware is ready.
This patch adds ACPI_SIG_IORT to the table, which enables IORT
from initrd to override which from firmware.
Linus Torvalds [Wed, 7 Feb 2018 03:57:31 +0000 (19:57 -0800)]
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
- membarrier updates (Mathieu Desnoyers)
- SMP balancing optimizations (Mel Gorman)
- stats update optimizations (Peter Zijlstra)
- RT scheduler race fixes (Steven Rostedt)
- misc fixes and updates
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Use a recently used CPU as an idle candidate and the basis for SIS
sched/fair: Do not migrate if the prev_cpu is idle
sched/fair: Restructure wake_affine*() to return a CPU id
sched/fair: Remove unnecessary parameters from wake_affine_idle()
sched/rt: Make update_curr_rt() more accurate
sched/rt: Up the root domain ref count when passing it around via IPIs
sched/rt: Use container_of() to get root domain in rto_push_irq_work_func()
sched/core: Optimize update_stats_*()
sched/core: Optimize ttwu_stat()
membarrier/selftest: Test private expedited sync core command
membarrier/arm64: Provide core serializing command
membarrier/x86: Provide core serializing command
membarrier: Provide core serializing command, *_SYNC_CORE
lockin/x86: Implement sync_core_before_usermode()
locking: Introduce sync_core_before_usermode()
membarrier/selftest: Test global expedited command
membarrier: Provide GLOBAL_EXPEDITED command
membarrier: Document scheduler barrier requirements
powerpc, membarrier: Skip memory barrier in switch_mm()
membarrier/selftest: Test private expedited command
Linus Torvalds [Wed, 7 Feb 2018 03:28:19 +0000 (19:28 -0800)]
Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixlets from Ingo Molnar:
"An endianness fix and a jump labels branch hint update"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/qrwlock: include asm/byteorder.h as needed
jump_label: Add branch hints to static_branch_{un,}likely()
1) Fix error path in netdevsim, from Jakub Kicinski.
2) Default values listed in tcp_wmem and tcp_rmem documentation were
inaccurate, from Tonghao Zhang.
3) Fix route leaks in SCTP, both for ipv4 and ipv6. From Alexey Kodanev
and Tommi Rantala.
4) Fix "MASK < Y" meant to be "MASK << Y" in xgbe driver, from Wolfram
Sang.
5) Use after free in u32_destroy_key(), from Paolo Abeni.
6) Fix two TX issues in be2net driver, from Suredh Reddy.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (25 commits)
be2net: Handle transmit completion errors in Lancer
be2net: Fix HW stall issue in Lancer
RDS: IB: Fix null pointer issue
nfp: fix kdoc warnings on nested structures
sample/bpf: fix erspan metadata
net: erspan: fix erspan config overwrite
net: erspan: fix metadata extraction
cls_u32: fix use after free in u32_destroy_key()
net: amd-xgbe: fix comparison to bitshift when dealing with a mask
net: phy: Handle not having GPIO enabled in the kernel
ibmvnic: fix empty firmware version and errors cleanup
sctp: fix dst refcnt leak in sctp_v4_get_dst
sctp: fix dst refcnt leak in sctp_v6_get_dst()
dwc-xlgmac: remove Jie Deng as co-maintainer
doc: Change the min default value of tcp_wmem/tcp_rmem.
samples/bpf: use bpf_set_link_xdp_fd
libbpf: add missing SPDX-License-Identifier
libbpf: add error reporting in XDP
libbpf: add function to setup XDP
tools: add netlink.h and if_link.h in tools uapi
...
Eric Biggers [Tue, 6 Feb 2018 23:42:08 +0000 (15:42 -0800)]
pipe: read buffer limits atomically
The pipe buffer limits are accessed without any locking, and may be
changed at any time by the sysctl handlers. In theory this could cause
problems for expressions like the following:
... since the assembly code might reference the 'pipe_user_pages_hard'
memory location multiple times, and if the admin removes the limit by
setting it to 0, there is a very brief window where processes could
incorrectly observe the limit to be exceeded.
Fix this by loading the limits with READ_ONCE() prior to use.
Eric Biggers [Tue, 6 Feb 2018 23:42:05 +0000 (15:42 -0800)]
pipe: simplify round_pipe_size()
round_pipe_size() calculates the number of pages the requested size
corresponds to, then rounds the page count up to the next power of 2.
However, it also rounds everything < PAGE_SIZE up to PAGE_SIZE.
Therefore, there's no need to actually translate the size into a page
count; we just need to round the size up to the next power of 2.
We do need to verify the size isn't greater than (1 << 31), since on
32-bit systems roundup_pow_of_two() would be undefined in that case. But
that can just be combined with the UINT_MAX check which we need anyway
now.
Finally, update pipe_set_size() to not redundantly check the return value
of round_pipe_size() for the "invalid size" case twice.
Eric Biggers [Tue, 6 Feb 2018 23:42:00 +0000 (15:42 -0800)]
pipe: reject F_SETPIPE_SZ with size over UINT_MAX
A pipe's size is represented as an 'unsigned int'. As expected, writing a
value greater than UINT_MAX to /proc/sys/fs/pipe-max-size fails with
EINVAL. However, the F_SETPIPE_SZ fcntl silently truncates such values to
32 bits, rather than failing with EINVAL as expected. (It *does* fail
with EINVAL for values above (1 << 31) but <= UINT_MAX.)
Fix this by moving the check against UINT_MAX into round_pipe_size() which
is called in both cases.
Eric Biggers [Tue, 6 Feb 2018 23:41:53 +0000 (15:41 -0800)]
pipe: actually allow root to exceed the pipe buffer limits
pipe-user-pages-hard and pipe-user-pages-soft are only supposed to apply
to unprivileged users, as documented in both Documentation/sysctl/fs.txt
and the pipe(7) man page.
However, the capabilities are actually only checked when increasing a
pipe's size using F_SETPIPE_SZ, not when creating a new pipe. Therefore,
if pipe-user-pages-hard has been set, the root user can run into it and be
unable to create pipes. Similarly, if pipe-user-pages-soft has been set,
the root user can run into it and have their pipes limited to 1 page each.
Fix this by allowing the privileged override in both cases.
Eric Biggers [Tue, 6 Feb 2018 23:41:49 +0000 (15:41 -0800)]
pipe, sysctl: remove pipe_proc_fn()
pipe_proc_fn() is no longer needed, as it only calls through to
proc_dopipe_max_size(). Just put proc_dopipe_max_size() in the ctl_table
entry directly, and remove the unneeded EXPORT_SYMBOL() and the ENOSYS
stub for it.
(The reason the ENOSYS stub isn't needed is that the pipe-max-size
ctl_table entry is located directly in 'kern_table' rather than being
registered separately. Therefore, the entry is already only defined when
the kernel is built with sysctl support.)
Eric Biggers [Tue, 6 Feb 2018 23:41:45 +0000 (15:41 -0800)]
pipe, sysctl: drop 'min' parameter from pipe-max-size converter
Patch series "pipe: buffer limits fixes and cleanups", v2.
This series simplifies the sysctl handler for pipe-max-size and fixes
another set of bugs related to the pipe buffer limits:
- The root user wasn't allowed to exceed the limits when creating new
pipes.
- There was an off-by-one error when checking the limits, so a limit of
N was actually treated as N - 1.
- F_SETPIPE_SZ accepted values over UINT_MAX.
- Reading the pipe buffer limits could be racy.
This patch (of 7):
Before validating the given value against pipe_min_size,
do_proc_dopipe_max_size_conv() calls round_pipe_size(), which rounds the
value up to pipe_min_size. Therefore, the second check against
pipe_min_size is redundant. Remove it.
Arnd Bergmann [Tue, 6 Feb 2018 23:41:41 +0000 (15:41 -0800)]
kasan: rework Kconfig settings
We get a lot of very large stack frames using gcc-7.0.1 with the default
-fsanitize-address-use-after-scope --param asan-stack=1 options, which can
easily cause an overflow of the kernel stack, e.g.
drivers/gpu/drm/i915/gvt/handlers.c:2434:1: warning: the frame size of 46176 bytes is larger than 3072 bytes
drivers/net/wireless/ralink/rt2x00/rt2800lib.c:5650:1: warning: the frame size of 23632 bytes is larger than 3072 bytes
lib/atomic64_test.c:250:1: warning: the frame size of 11200 bytes is larger than 3072 bytes
drivers/gpu/drm/i915/gvt/handlers.c:2621:1: warning: the frame size of 9208 bytes is larger than 3072 bytes
drivers/media/dvb-frontends/stv090x.c:3431:1: warning: the frame size of 6816 bytes is larger than 3072 bytes
fs/fscache/stats.c:287:1: warning: the frame size of 6536 bytes is larger than 3072 bytes
To reduce this risk, -fsanitize-address-use-after-scope is now split out
into a separate CONFIG_KASAN_EXTRA Kconfig option, leading to stack
frames that are smaller than 2 kilobytes most of the time on x86_64. An
earlier version of this patch also prevented combining KASAN_EXTRA with
KASAN_INLINE, but that is no longer necessary with gcc-7.0.1.
All patches to get the frame size below 2048 bytes with CONFIG_KASAN=y
and CONFIG_KASAN_EXTRA=n have been merged by maintainers now, so we can
bring back that default now. KASAN_EXTRA=y still causes lots of
warnings but now defaults to !COMPILE_TEST to disable it in
allmodconfig, and it remains disabled in all other defconfigs since it
is a new option. I arbitrarily raise the warning limit for KASAN_EXTRA
to 3072 to reduce the noise, but an allmodconfig kernel still has around
50 warnings on gcc-7.
I experimented a bit more with smaller stack frames and have another
follow-up series that reduces the warning limit for 64-bit architectures
to 1280 bytes (without CONFIG_KASAN).
With earlier versions of this patch series, I also had patches to address
the warnings we get with KASAN and/or KASAN_EXTRA, using a
"noinline_if_stackbloat" annotation.
That annotation now got replaced with a gcc-8 bugfix (see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715) and a workaround for
older compilers, which means that KASAN_EXTRA is now just as bad as
before and will lead to an instant stack overflow in a few extreme
cases.
This reverts parts of commit 3f181b4d8652 ("lib/Kconfig.debug: disable
-Wframe-larger-than warnings with KASAN=y"). Two patches in linux-next
should be merged first to avoid introducing warnings in an allmodconfig
build: 3cd890dbe2a4 ("media: dvb-frontends: fix i2c access helpers for KASAN") 16c3ada89cff ("media: r820t: fix r820t_write_reg for KASAN")
Do we really need to backport this?
I think we do: without this patch, enabling KASAN will lead to
unavoidable kernel stack overflow in certain device drivers when built
with gcc-7 or higher on linux-4.10+ or any version that contains a
backport of commit c5caf21ab0cf8. Most people are probably still on
older compilers, but it will get worse over time as they upgrade their
distros.
The warnings we get on kernels older than this should all be for code
that uses dangerously large stack frames, though most of them do not
cause an actual stack overflow by themselves.The asan-stack option was
added in linux-4.0, and commit 3f181b4d8652 ("lib/Kconfig.debug:
disable -Wframe-larger-than warnings with KASAN=y") effectively turned
off the warning for allmodconfig kernels, so I would like to see this
fix backported to any kernels later than 4.0.
I have done dozens of fixes for individual functions with stack frames
larger than 2048 bytes with asan-stack, and I plan to make sure that
all those fixes make it into the stable kernels as well (most are
already there).
Part of the complication here is that asan-stack (from 4.0) was
originally assumed to always require much larger stacks, but that
turned out to be a combination of multiple gcc bugs that we have now
worked around and fixed, but sanitize-address-use-after-scope (from
v4.10) has a much higher inherent stack usage and also suffers from at
least three other problems that we have analyzed but not yet fixed
upstream, each of them makes the stack usage more severe than it should
be.
The file was converted from print_symbol() to %pf some time ago in
commit ef26f20cd117 ("genirq: Print threaded handler in spurious debug
output"). kallsyms does not seem to be needed anymore.
The file was converted from print_symbol() to %pSR a while ago in commit 071361d3473e ("mm: Convert print_symbol to %pSR"). kallsyms does not
seem to be needed anymore.
Shakeel Butt [Tue, 6 Feb 2018 23:40:59 +0000 (15:40 -0800)]
vfs: remove might_sleep() from clear_inode()
Commit 7994e6f72543 ("vfs: Move waiting for inode writeback from
end_writeback() to evict_inode()") removed inode_sync_wait() from
end_writeback() and commit dbd5768f87ff ("vfs: Rename end_writeback() to
clear_inode()") renamed end_writeback() to clear_inode().
After these patches there is no sleeping operation in clear_inode().
So, remove might_sleep() from it.
Jonathan Haws [Tue, 6 Feb 2018 23:40:52 +0000 (15:40 -0800)]
ipc/mqueue.c: have RT tasks queue in by priority in wq_add()
Previous behavior added tasks to the work queue using the static_prio
value instead of the dynamic priority value in prio. This caused RT tasks
to be added to the work queue in a FIFO manner rather than by priority.
Normal tasks were handled by priority.
This fix utilizes the dynamic priority of the task to ensure that both RT
and normal tasks are added to the work queue in priority order. Utilizing
the dynamic priority (prio) rather than the base priority (normal_prio)
was chosen to ensure that if a task had a boosted priority when it was
added to the work queue, it would be woken sooner to to ensure that it
releases any other locks it may be holding in a more timely manner. It is
understood that the task could have a lower priority when it wakes than
when it was added to the queue in this (unlikely) case.
As described in the title, this patch fixes <ipc>id_ds inconsistency when
<ipc>ctl_stat executes concurrently with some ds-changing function, e.g.
shmat, msgsnd or whatever.
For instance, if shmctl(IPC_STAT) is running concurrently
with shmat, following data structure can be returned:
{... shm_lpid = 0, shm_nattch = 1, ...}
Similarly to type mismatch checks, new GCC 8.x and Clang also changed for
ABI for returns_nonnull checks. While we can update our code to conform
the new ABI it's more reasonable to just remove it. Because it's just
dead code, we don't have any single user of returns_nonnull attribute in
the whole kernel.
And AFAIU the advantage that this attribute could bring would be mitigated
by -fno-delete-null-pointer-checks cflag that we use to build the kernel.
So it's unlikely we will have a lot of returns_nonnull attribute in
future.
Andrey Ryabinin [Tue, 6 Feb 2018 23:40:42 +0000 (15:40 -0800)]
lib/ubsan: add type mismatch handler for new GCC/Clang
UBSAN=y fails to build with new GCC/clang:
arch/x86/kernel/head64.o: In function `sanitize_boot_params':
arch/x86/include/asm/bootparam_utils.h:37: undefined reference to `__ubsan_handle_type_mismatch_v1'
because Clang and GCC 8 slightly changed ABI for 'type mismatch' errors.
Compiler now uses new __ubsan_handle_type_mismatch_v1() function with
slightly modified 'struct type_mismatch_data'.
Let's add new 'struct type_mismatch_data_common' which is independent from
compiler's layout of 'struct type_mismatch_data'. And make
__ubsan_handle_type_mismatch[_v1]() functions transform compiler-dependent
type mismatch data to our internal representation. This way, we can
support both old and new compilers with minimal amount of change.
Dmitry Vyukov [Tue, 6 Feb 2018 23:40:28 +0000 (15:40 -0800)]
kcov: detect double association with a single task
Currently KCOV_ENABLE does not check if the current task is already
associated with another kcov descriptor. As the result it is possible
to associate a single task with more than one kcov descriptor, which
later leads to a memory leak of the old descriptor. This relation is
really meant to be one-to-one (task has only one back link).
Arnd Bergmann [Tue, 6 Feb 2018 23:40:21 +0000 (15:40 -0800)]
pps: parport: use timespec64 instead of timespec
getnstimeofday() is deprecated, so I'm converting this to use
ktime_get_real_ts64() as a safe replacement. I considered using
ktime_get_real() instead, but since the algorithm here depends on the
exact timing, I decided to introduce fewer changes and leave the code
that determines the nanoseconds since the last seconds wrap untouched.
It's not entirely clear to me whether we should also change the time
base to CLOCK_BOOTTIME or CLOCK_TAI. With boottime, we would be
independent of changes due to settimeofday() and only see the speed
adjustment from the upstream clock source, with the downside of having
the signal be at an arbirary offset from the start of the UTC second
signal. With CLOCK_TAI, we would use the same offset from the UTC
second as before and still suffer from settimeofday() adjustments, but
would be less confused during leap seconds.
Both boottime and tai only offer usable (i.e. avoiding ktime_t to
timespec64 conversion) interfaces for ktime_t though, so either way,
changing it wouldn't take significantly more work. CLOCK_MONOTONIC
could be used with ktime_get_ts64(), but would lose synchronization
across a suspend/resume cycle, which seems worse.
Markus Elfring [Tue, 6 Feb 2018 23:39:51 +0000 (15:39 -0800)]
rapidio: improve a size determination in five functions
Replace the specification of data structures by pointer dereferences as
the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style
convention.
This issue was detected by using the Coccinelle software.
When creating a file inside a directory that has the setgid flag set, give
the new file the group ID of the parent, and also the setgid flag if it is
a directory itself.
Arnd Bergmann [Tue, 6 Feb 2018 23:39:21 +0000 (15:39 -0800)]
nilfs2: use time64_t internally
The superblock and segment timestamps are used only internally in nilfs2
and can be read out using sysfs.
Since we are using the old 'get_seconds()' interface and store the data
as timestamps, the behavior differs slightly between 64-bit and 32-bit
kernels, the latter will show incorrect timestamps after 2038 in sysfs,
and presumably fail completely in 2106 as comparisons go wrong.
This changes nilfs2 to use time64_t with ktime_get_real_seconds() to
handle timestamps, making the behavior consistent and correct on both
32-bit and 64-bit machines.
The on-disk format already uses 64-bit timestamps, so nothing changes
there.
Alexey Dobriyan [Tue, 6 Feb 2018 23:39:13 +0000 (15:39 -0800)]
elf: fix NT_FILE integer overflow
If vm.max_map_count bumped above 2^26 (67+ mil) and system has enough RAM
to allocate all the VMAs (~12.8 GB on Fedora 27 with 200-byte VMAs), then
it should be possible to overflow 32-bit "size", pass paranoia check,
allocate very little vmalloc space and oops while writing into vmalloc
guard page...
But I didn't test this, only coredump of regular process.
Joe Perches [Tue, 6 Feb 2018 23:39:06 +0000 (15:39 -0800)]
checkpatch: avoid some false positives for TABSTOP declaration test
Using an open bracket after what seems to be a declaration can also be a
function definition and declaration argument line continuation so remove
the open bracket from the possible declaration/definition matching.
Joe Perches [Tue, 6 Feb 2018 23:39:03 +0000 (15:39 -0800)]
checkpatch: exclude drivers/staging from if with unnecessary parentheses test
Greg KH doesn't like this test so exclude the staging directory from the
implied --strict only test unless --strict is actually used on the
command-line.
Allow lines with URL to exceed the 80 char limit for improved interaction
in adaption to ongoing but undocumented practice.
$ git grep -E '://\S{77}.*' -- '*.[ch]'
As per RFC3986 [1], the URL format allows for alphanum, +, - and .
characters in the scheme before the separator :// as long as it starts
with a letter (e.g. https, git, f.-+).
Recognition of URIs without more context information is prone to false
positives and thus currently left out of the heuristics.
$rawline is used in the check as comments are removed from $line.
Pravin Shedge [Tue, 6 Feb 2018 23:38:42 +0000 (15:38 -0800)]
lib/test_sort.c: add module unload support
test_sort.c performs array-based and linked list sort test. Code allows
to compile either as a loadable modules or builtin into the kernel.
Current code is not allow to unload the test_sort.ko module after
successful completion.
This patch adds support to unload the "test_sort.ko" module by adding
module_exit support.
Previous patch was implemented auto unload support by returning -EAGAIN
from module_init() function on successful case, but this approach is not
ideal.
The auto-unload might seem like a nice optimization, but it encourages
inconsistent behaviour. And behaviour that is different from all other
normal modules.
Vincent Legoll [Tue, 6 Feb 2018 23:38:38 +0000 (15:38 -0800)]
lib/: make RUNTIME_TESTS a menuconfig to ease disabling it all
No need to get into the submenu to disable all related config entries.
This makes it easier to disable all RUNTIME_TESTS config options without
entering the submenu. It will also enable one to see that en/dis-abled
state from the outside menu.
This is only intended to change menuconfig UI, not change the config
dependencies.
Clement Courbet [Tue, 6 Feb 2018 23:38:34 +0000 (15:38 -0800)]
lib: optimize cpumask_next_and()
We've measured that we spend ~0.6% of sys cpu time in cpumask_next_and().
It's essentially a joined iteration in search for a non-zero bit, which is
currently implemented as a lookup join (find a nonzero bit on the lhs,
lookup the rhs to see if it's set there).
Implement a direct join (find a nonzero bit on the incrementally built
join). Also add generic bitmap benchmarks in the new `test_find_bit`
module for new function (see `find_next_and_bit` in [2] and [3] below).
For cpumask_next_and, direct benchmarking shows that it's 1.17x to 14x
faster with a geometric mean of 2.1 on 32 CPUs [1]. No impact on memory
usage. Note that on Arm, the new pure-C implementation still outperforms
the old one that uses a mix of C and asm (`find_next_bit`) [3].
[1] Approximate benchmark code:
```
unsigned long src1p[nr_cpumask_longs] = {pattern1};
unsigned long src2p[nr_cpumask_longs] = {pattern2};
for (/*a bunch of repetitions*/) {
for (int n = -1; n <= nr_cpu_ids; ++n) {
asm volatile("" : "+rm"(src1p)); // prevent any optimization
asm volatile("" : "+rm"(src2p));
unsigned long result = cpumask_next_and(n, src1p, src2p);
asm volatile("" : "+rm"(result));
}
}
```
Yury Norov [Tue, 6 Feb 2018 23:38:31 +0000 (15:38 -0800)]
lib/find_bit_benchmark.c: improvements
As suggested in review comments:
* printk: align numbers using whitespaces instead of tabs;
* return error value from init() to avoid calling rmmod if testing again;
* use ktime_get instead of get_cycles as some arches don't support it;
lib/stackdepot.c: use a non-instrumented version of memcmp()
stackdepot used to call memcmp(), which compiler tools normally
instrument, therefore every lookup used to unnecessarily call instrumented
code. This is somewhat ok in the case of KASAN, but under KMSAN a lot of
time was spent in the instrumentation.
Andy Shevchenko [Tue, 6 Feb 2018 23:38:20 +0000 (15:38 -0800)]
include/linux/bitmap.h: make bitmap_fill() and bitmap_zero() consistent
Behaviour of bitmap_fill() differs from bitmap_zero() in a way how bits
behind bitmap are handed. bitmap_zero() clears entire bitmap by unsigned
long boundary, while bitmap_fill() mimics bitmap_set().
Here we change bitmap_fill() behaviour to be consistent with bitmap_zero()
and add a note to documentation.
The change might reveal some bugs in the code where unused bits are
handled differently and in such cases bitmap_set() has to be used.
Andy Shevchenko [Tue, 6 Feb 2018 23:38:17 +0000 (15:38 -0800)]
lib/test_bitmap.c: clean up test_zero_fill_copy() test case and rename
Since we have separate explicit test cases for bitmap_zero() /
bitmap_clear() and bitmap_fill() / bitmap_set(), clean up
test_zero_fill_copy() to only test bitmap_copy() functionality and thus
rename a function to reflect the changes.
While here, replace bitmap_fill() by bitmap_set() with proper values.