Andi Kleen [Mon, 8 May 2017 22:58:50 +0000 (15:58 -0700)]
kref: remove WARN_ON for NULL release functions
The kref functions check for NULL release functions. This WARN_ON seems
rather pointless. We will eventually release and then just crash
nicely. It is also somewhat expensive because these functions are
inlined in a lot of places. Removing the WARN_ONs saves around 2.3k in
this kernel (likely more in others with more drivers)
Laura Abbott [Mon, 8 May 2017 22:57:59 +0000 (15:57 -0700)]
treewide: move set_memory_* functions away from cacheflush.h
Patch series "set_memory_* functions header refactor", v3.
The set_memory_* APIs came out of a desire to have a better way to
change memory attributes. Many of these attributes were linked to cache
functionality so the prototypes were put in cacheflush.h. These days,
the APIs have grown and have a much wider use than just cache APIs. To
support this growth, split off set_memory_* and friends into a separate
header file to avoid growing cacheflush.h for APIs that have nothing to
do with caches.
The only problem is that many people are not aware that they really want
to give __GFP_HIGHMEM along with other flags because there is really no
reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages
which are mapped to the kernel vmalloc space. About half of users don't
use this flag, though. This signals that we make the API unnecessarily
too complex.
This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to
be mapped to the vmalloc space. Current users which add __GFP_HIGHMEM
are simplified and drop the flag.
Huang Ying [Mon, 8 May 2017 22:57:40 +0000 (15:57 -0700)]
mm, swap: use kvzalloc to allocate some swap data structures
Now vzalloc() is used in swap code to allocate various data structures,
such as swap cache, swap slots cache, cluster info, etc. Because the
size may be too large on some system, so that normal kzalloc() may fail.
But using kzalloc() has some advantages, for example, less memory
fragmentation, less TLB pressure, etc. So change the data structure
allocation in swap code to use kvzalloc() which will try kzalloc()
firstly, and fallback to vzalloc() if kzalloc() failed.
In general, although kmalloc() will reduce the number of high-order
pages in short term, vmalloc() will cause more pain for memory
fragmentation in the long term. And the swap data structure allocation
that is changed in this patch is expected to be long term allocation.
From Dave Hansen:
"for example, we have a two-page data structure. vmalloc() takes two
effectively random order-0 pages, probably from two different 2M pages
and pins them. That "kills" two 2M pages. kmalloc(), allocating two
*contiguous* pages, will not cross a 2M boundary. That means it will
only "kill" the possibility of a single 2M page. More 2M pages == less
fragmentation.
The allocation in this patch occurs during swap on time, which is
usually done during system boot, so usually we have high opportunity to
allocate the contiguous pages successfully.
The allocation for swap_map[] in struct swap_info_struct is not changed,
because that is usually quite large and vmalloc_to_page() is used for
it. That makes it a little harder to change.
Michal Hocko [Mon, 8 May 2017 22:57:37 +0000 (15:57 -0700)]
drivers/md/bcache/super.c: use kvmalloc
bcache_device_init uses kmalloc for small requests and vmalloc for those
which are larger than 64 pages. This alone is a strange criterion.
Moreover kmalloc can fallback to vmalloc on the failure. Let's simply
use kvmalloc instead as it knows how to handle the fallback properly
Michal Hocko [Mon, 8 May 2017 22:57:34 +0000 (15:57 -0700)]
drivers/md/dm-ioctl.c: use kvmalloc rather than opencoded variant
copy_params uses kmalloc with vmalloc fallback. We already have a
helper for that - kvmalloc. This caller requires GFP_NOIO semantic so
it hasn't been converted with many others by previous patches. All we
need to achieve this semantic is to use the scope
memalloc_noio_{save,restore} around kvmalloc.
Michal Hocko [Mon, 8 May 2017 22:57:31 +0000 (15:57 -0700)]
net: use kvmalloc with __GFP_REPEAT rather than open coded variant
fq_alloc_node, alloc_netdev_mqs and netif_alloc* open code kmalloc with
vmalloc fallback. Use the kvmalloc variant instead. Keep the
__GFP_REPEAT flag based on explanation from Eric:
"At the time, tests on the hardware I had in my labs showed that
vmalloc() could deliver pages spread all over the memory and that was
a small penalty (once memory is fragmented enough, not at boot time)"
The way how the code is constructed means, however, that we prefer to go
and hit the OOM killer before we fall back to the vmalloc for requests
<=32kB (with 4kB pages) in the current code. This is rather disruptive
for something that can be achived with the fallback. On the other hand
__GFP_REPEAT doesn't have any useful semantic for these requests. So
the effect of this patch is that requests which fit into 32kB will fall
back to vmalloc easier now.
Michal Hocko [Mon, 8 May 2017 22:57:27 +0000 (15:57 -0700)]
treewide: use kv[mz]alloc* rather than opencoded variants
There are many code paths opencoding kvmalloc. Let's use the helper
instead. The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator. E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation. This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously. There is no guarantee something like that happens
though.
This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.
Michal Hocko [Mon, 8 May 2017 22:57:24 +0000 (15:57 -0700)]
fs/xattr.c: zero out memory copied to userspace in getxattr
getxattr uses vmalloc to allocate memory if kzalloc fails. This is
filled by vfs_getxattr and then copied to the userspace. vmalloc,
however, doesn't zero out the memory so if the specific implementation
of the xattr handler is sloppy we can theoretically expose a kernel
memory. There is no real sign this is really the case but let's make
sure this will not happen and use vzalloc instead.
Michal Hocko [Mon, 8 May 2017 22:57:21 +0000 (15:57 -0700)]
net/ipv6/ila/ila_xlat.c: simplify a strange allocation pattern
alloc_ila_locks seemed to c&p from alloc_bucket_locks allocation pattern
which is quite unusual. The default allocation size is 320 *
sizeof(spinlock_t) which is sub page unless lockdep is enabled when the
performance benefit is really questionable and not worth the subtle code
IMHO. Also note that the context when we call ila_init_net (modprobe or
a task creating a net namespace) has to be properly configured.
Let's just simplify the code and use kvmalloc helper which is a
transparent way to use kmalloc with vmalloc fallback.
Michal Hocko [Mon, 8 May 2017 22:57:18 +0000 (15:57 -0700)]
lib/rhashtable.c: simplify a strange allocation pattern
alloc_bucket_locks allocation pattern is quite unusual. We are
preferring vmalloc when CONFIG_NUMA is enabled. The rationale is that
vmalloc will respect the memory policy of the current process and so the
backing memory will get distributed over multiple nodes if the requester
is configured properly. At least that is the intention, in reality
rhastable is shrunk and expanded from a kernel worker so no mempolicy
can be assumed.
Let's just simplify the code and use kvmalloc helper, which is a
transparent way to use kmalloc with vmalloc fallback, if the caller is
allowed to block and use the flag otherwise.
Michal Hocko [Mon, 8 May 2017 22:57:15 +0000 (15:57 -0700)]
mm: support __GFP_REPEAT in kvmalloc_node for >32kB
vhost code uses __GFP_REPEAT when allocating vhost_virtqueue resp.
vhost_vsock because it would really like to prefer kmalloc to the
vmalloc fallback - see 23cc5a991c7a ("vhost-net: extend device
allocation to vmalloc") for more context. Michael Tsirkin has also
noted:
"__GFP_REPEAT overhead is during allocation time. Using vmalloc means
all accesses are slowed down. Allocation is not on data path, accesses
are."
The similar applies to other vhost_kvzalloc users.
Let's teach kvmalloc_node to handle __GFP_REPEAT properly. There are
two things to be careful about. First we should prevent from the OOM
killer and so have to involve __GFP_NORETRY by default and secondly
override __GFP_REPEAT for !costly order requests as the __GFP_REPEAT is
ignored for !costly orders.
Supporting __GFP_REPEAT like semantic for !costly request is possible it
would require changes in the page allocator. This is out of scope of
this patch.
This patch shouldn't introduce any functional change.
Michal Hocko [Mon, 8 May 2017 22:57:12 +0000 (15:57 -0700)]
mm, vmalloc: properly track vmalloc users
__vmalloc_node_flags used to be static inline but this has changed by
"mm: introduce kv[mz]alloc helpers" because kvmalloc_node needs to use
it as well and the code is outside of the vmalloc proper. I haven't
realized that changing this will lead to a subtle bug though. The
function is responsible to track the caller as well. This caller is
then printed by /proc/vmallocinfo. If __vmalloc_node_flags is not
inline then we would get only direct users of __vmalloc_node_flags as
callers (e.g. v[mz]alloc) which reduces usefulness of this debugging
feature considerably. It simply doesn't help to see that the given
range belongs to vmalloc as a caller:
Michal Hocko [Mon, 8 May 2017 22:57:09 +0000 (15:57 -0700)]
mm: introduce kv[mz]alloc helpers
Patch series "kvmalloc", v5.
There are many open coded kmalloc with vmalloc fallback instances in the
tree. Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.
As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.
Most callers, I could find, have been converted to use the helper
instead. This is patch 6. There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.
Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code. Yet we do not have any common helper
for that and so users have invented their own helpers. Some of them are
really creative when doing so. Let's just add kv[mz]alloc and make sure
it is implemented properly. This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures. This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.
This patch also changes some existing users and removes helpers which
are specific for them. In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL). Those need to be
fixed separately.
While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers. Existing ones would have to die
slowly.
Davidlohr Bueso [Mon, 8 May 2017 22:57:06 +0000 (15:57 -0700)]
sysv,ipc: cacheline align kern_ipc_perm
Assign 'struct kern_ipc_perm' its own cacheline to avoid false sharing
with sysv ipc calls.
While the structure itself is rather read-mostly throughout the lifespan
of ipc, the spinlock causes most of the invalidations. One example is
commit 31a7c4746e9 ("ipc/sem.c: cacheline align the ipc spinlock for
semaphores"). Therefore, extend this to all ipc.
The effect of cacheline alignment on sems can be seen in sembench, which
deals mostly with semtimedop wait/wakes is seen to improve raw
throughput (worker loops) between 8 to 12% on a 24-core x86 with over 4
threads.
Arnd Bergmann [Mon, 8 May 2017 22:57:00 +0000 (15:57 -0700)]
initramfs: use vfs_stat/lstat directly
sys_newlstat is a system call implementation that is meant for user
space, and that copies kernel-internal data structure to the user
format, which is not needed for in-kernel users.
Further, as we rearrange the system call implementation so we can extend
it with 64-bit time_t, the prototype for sys_newlstat changes.
This changes the initramfs code to use vfs_lstat directly, to get it out
of the way of the time_t changes, and make it slightly more efficient in
the process. Along the same lines we also replace sys_stat and
sys_stat64 with vfs_stat.
Daniel Thompson [Mon, 8 May 2017 22:56:57 +0000 (15:56 -0700)]
initramfs: provide a way to ignore image provided by bootloader
Many "embedded" architectures provide CMDLINE_FORCE to allow the kernel
to override the command line provided by an inflexible bootloader.
However there is currrently no way for the kernel to override the
initramfs image provided by the bootloader meaning there are still ways
for bootloaders to make things difficult for us.
Fix this by introducing INITRAMFS_FORCE which can prevent the kernel
from loading the bootloader supplied image.
We use CMDLINE_FORCE (and its friend CMDLINE_EXTEND) to imply that the
system has an inflexible bootloader. This allow us to avoid presenting
this config option to users of systems where inflexible bootloaders
aren't usually a problem.
Dmitry Vyukov [Mon, 8 May 2017 22:56:51 +0000 (15:56 -0700)]
lib/fault-inject.c: use correct check for interrupts
in_interrupt() also returns true when bh is disabled in task context.
That's not what fail_task() wants to check. Use the new in_task()
predicate that does the right thing.
Dmitry Vyukov [Mon, 8 May 2017 22:56:48 +0000 (15:56 -0700)]
kcov: simplify interrupt check
in_interrupt() semantics are confusing and wrong for most users as it
also returns true when bh is disabled. Thus we open coded a proper
check for interrupts in __sanitizer_cov_trace_pc() with a lengthy
explanatory comment.
Kirill Tkhai [Mon, 8 May 2017 22:56:41 +0000 (15:56 -0700)]
pidns: expose task pid_ns_for_children to userspace
pid_ns_for_children set by a task is known only to the task itself, and
it's impossible to identify it from outside.
It's a big problem for checkpoint/restore software like CRIU, because it
can't correctly handle tasks, that do setns(CLONE_NEWPID) in proccess of
their work.
This patch solves the problem, and it exposes pid_ns_for_children to ns
directory in standard way with the name "pid_for_children":
~# ls /proc/5531/ns -l | grep pid
lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid -> pid:[4026531836]
lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid_for_children -> pid:[4026532286]
Kirill Tkhai [Mon, 8 May 2017 22:56:38 +0000 (15:56 -0700)]
ns: allow ns_entries to have custom symlink content
Patch series "Expose task pid_ns_for_children to userspace".
pid_ns_for_children set by a task is known only to the task itself, and
it's impossible to identify it from outside.
It's a big problem for checkpoint/restore software like CRIU, because it
can't correctly handle tasks, that do setns(CLONE_NEWPID) in proccess of
their work. If they have a custom pid_ns_for_children before dump, they
must have the same ns after restore. Otherwise, restored task bumped
into enviroment it does not expect.
This patchset solves the problem. It exposes pid_ns_for_children to ns
directory in standard way with the name "pid_for_children":
~# ls /proc/5531/ns -l | grep pid
lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid -> pid:[4026531836]
lrwxrwxrwx 1 root root 0 Jan 14 16:38 pid_for_children -> pid:[4026532286]
This patch (of 2):
Make possible to have link content prefix yyy different from the link
name xxx:
Kirill Tkhai [Mon, 8 May 2017 22:56:34 +0000 (15:56 -0700)]
pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()
alloc_pidmap() advances pid_namespace::last_pid. When first pid
allocation fails, then next created process will have pid 2 and
pid_ns_prepare_proc() won't be called. So, pid_namespace::proc_mnt will
never be initialized (not to mention that there won't be a child
reaper).
I saw crash stack of such case on kernel 3.10:
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: proc_flush_task+0x8f/0x1b0
Call Trace:
release_task+0x3f/0x490
wait_consider_task.part.10+0x7ff/0xb00
do_wait+0x11f/0x280
SyS_wait4+0x7d/0x110
We may fix this by restore of last_pid in 0 or by prohibiting of futher
allocations. Since there was a similar issue in Oleg Nesterov's commit 314a8ad0f18a ("pidns: fix free_pid() to handle the first fork failure").
and it was fixed via prohibiting allocation, let's follow this way, and
do the same.
Hari Bathini [Mon, 8 May 2017 22:56:31 +0000 (15:56 -0700)]
powerpc/fadump: update documentation about crashkernel parameter reuse
As we are reusing crashkernel parameter instead of fadump_reserve_mem
parameter to specify the memory to reserve for fadump's crash kernel,
update the documentation accordingly.
Hari Bathini [Mon, 8 May 2017 22:56:28 +0000 (15:56 -0700)]
powerpc/fadump: reuse crashkernel parameter for fadump memory reservation
fadump supports specifying memory to reserve for fadump's crash kernel
with fadump_reserve_mem kernel parameter. This parameter currently
supports passing a fixed memory size, like fadump_reserve_mem=<size>
only. This patch aims to add support for other syntaxes like
range-based memory size
<range1>:<size1>[,<range2>:<size2>,<range3>:<size3>,...] which allows
using the same parameter to boot the kernel with different system RAM
sizes.
As crashkernel parameter already supports the above mentioned syntaxes,
this patch deprecates fadump_reserve_mem parameter and reuses
crashkernel parameter instead, to specify memory for fadump's crash
kernel memory reservation as well. If any offset is provided in
crashkernel parameter, it will be ignored in case of fadump, as fadump
reserves memory at end of RAM.
Advantages using crashkernel parameter instead of fadump_reserve_mem
parameter are one less kernel parameter overall, code reuse and support
for multiple syntaxes to specify memory.
Hari Bathini [Mon, 8 May 2017 22:56:24 +0000 (15:56 -0700)]
powerpc/fadump: remove dependency with CONFIG_KEXEC
Now that crashkernel parameter parsing and vmcoreinfo related code is
moved under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE, remove
dependency with CONFIG_KEXEC for CONFIG_FA_DUMP. While here, get rid of
definitions of fadump_append_elf_note() & fadump_final_note() functions
to reuse similar functions compiled under CONFIG_CRASH_CORE.
Hari Bathini [Mon, 8 May 2017 22:56:21 +0000 (15:56 -0700)]
ia64: reuse append_elf_note() and final_note() functions
Get rid of multiple definitions of append_elf_note() & final_note()
functions. Reuse these functions compiled under CONFIG_CRASH_CORE Also,
define Elf_Word and use it instead of generic u32 or the more specific
Elf64_Word.
Hari Bathini [Mon, 8 May 2017 22:56:18 +0000 (15:56 -0700)]
crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE
Patch series "kexec/fadump: remove dependency with CONFIG_KEXEC and
reuse crashkernel parameter for fadump", v4.
Traditionally, kdump is used to save vmcore in case of a crash. Some
architectures like powerpc can save vmcore using architecture specific
support instead of kexec/kdump mechanism. Such architecture specific
support also needs to reserve memory, to be used by dump capture kernel.
crashkernel parameter can be a reused, for memory reservation, by such
architecture specific infrastructure.
This patchset removes dependency with CONFIG_KEXEC for crashkernel
parameter and vmcoreinfo related code as it can be reused without kexec
support. Also, crashkernel parameter is reused instead of
fadump_reserve_mem to reserve memory for fadump.
The first patch moves crashkernel parameter parsing and vmcoreinfo
related code under CONFIG_CRASH_CORE instead of CONFIG_KEXEC_CORE. The
second patch reuses the definitions of append_elf_note() & final_note()
functions under CONFIG_CRASH_CORE in IA64 arch code. The third patch
removes dependency on CONFIG_KEXEC for firmware-assisted dump (fadump)
in powerpc. The next patch reuses crashkernel parameter for reserving
memory for fadump, instead of the fadump_reserve_mem parameter. This
has the advantage of using all syntaxes crashkernel parameter supports,
for fadump as well. The last patch updates fadump kernel documentation
about use of crashkernel parameter.
This patch (of 5):
Traditionally, kdump is used to save vmcore in case of a crash. Some
architectures like powerpc can save vmcore using architecture specific
support instead of kexec/kdump mechanism. Such architecture specific
support also needs to reserve memory, to be used by dump capture kernel.
crashkernel parameter can be a reused, for memory reservation, by such
architecture specific infrastructure.
But currently, code related to vmcoreinfo and parsing of crashkernel
parameter is built under CONFIG_KEXEC_CORE. This patch introduces
CONFIG_CRASH_CORE and moves the above mentioned code under this config,
allowing code reuse without dependency on CONFIG_KEXEC. There is no
functional change with this patch.
Alexey Dobriyan [Mon, 8 May 2017 22:56:15 +0000 (15:56 -0700)]
cpumask: make "nr_cpumask_bits" unsigned
Bit searching functions accept "unsigned long" indices but
"nr_cpumask_bits" is "int" which is signed, so inevitable sign
extensions occur on x86_64. Those MOVSX are #1 MOVSX bloat by number of
uses across whole kernel.
Change "nr_cpumask_bits" to unsigned, this number can't be negative
after all. It allows to do implicit zero-extension on x86_64 without
MOVSX.
Change signed comparisons into unsigned comparisons where necessary.
Other uses looks fine because it is either argument passed to a function
or comparison is already unsigned.
Net win on allyesconfig type of kernel: ~2.8 KB (!)
Same arguments apply to "nr_cpu_ids" but I haven't yet found enough
courage to delve into this issue (and proper fix may require new type
"cpu_t" which is whole separate story).
Hoeun Ryu [Mon, 8 May 2017 22:56:11 +0000 (15:56 -0700)]
fork: free vmapped stacks in cache when cpus are offline
Using virtually mapped stack, kernel stacks are allocated via vmalloc.
In the current implementation, two stacks per cpu can be cached when
tasks are freed and the cached stacks are used again in task
duplications. But the cached stacks may remain unfreed even when cpu
are offline. By adding a cpu hotplug callback to free the cached stacks
when a cpu goes offline, the pages of the cached stacks are not wasted.
Kees Cook [Mon, 8 May 2017 22:56:08 +0000 (15:56 -0700)]
reiserfs: use designated initializers
Prepare to mark sensitive kernel structures for randomization by making
sure they're using designated initializers. These were identified
during allyesconfig builds of x86, arm, and arm64, with most initializer
fixes extracted from grsecurity.
Joe Perches [Mon, 8 May 2017 22:56:05 +0000 (15:56 -0700)]
checkpatch: improve the SUSPECT_CODE_INDENT test
The current SUSPECT_CODE_INDENT test does not recognize several
defective code style defects where code following a logical test is
inappropriately indented.
Before this patch, for code like:
if (foo)
bar();
checkpatch would not emit a warning.
Improve the test to warn when code after a logical test has the same
indentation as the logical test.
Perform the same indentation test for "else" blocks too.
Joe Perches [Mon, 8 May 2017 22:56:02 +0000 (15:56 -0700)]
checkpatch: improve the embedded function name test for patch contexts
The current test works only for a single patch context as it is done in
the foreach ($rawlines) loop that precedes the loop where the actual
$context_function variable is used.
Move the set of $context_function into the foreach (@lines) loop where
it is useful for each patch context.
When using checkpatch on out-of-tree code, it may occur that some
project-specific types are used, which will cause spurious warnings.
Add the --typedefsfile option as a way to extend the known types and
deal with this issue.
This was developed for OP-TEE [1]. We run a Travis job on all pull
requests [2], and checkpatch is part of that. The typical false warning
we get on a regular basis is with some pointers to functions returning
TEE_Result [3], which is a typedef from the GlobalPlatform APIs. We
consider it is acceptable to use GP types in the OP-TEE core
implementation, that's why this patch would be helpful for us.
Wei Wang [Mon, 8 May 2017 22:55:54 +0000 (15:55 -0700)]
checkpatch: special audit for revert commit line
Currently checkpatch.pl does not recognize git's default commit revert
message and will complain about the hash format. Add special audit for
revert commit message line to fix it.
Joe Perches [Mon, 8 May 2017 22:55:42 +0000 (15:55 -0700)]
checkpatch: allow space leading blank lines in email headers
Allow a leading space and otherwise blank link in the email headers as
it can be a line wrapped Spamassassin multiple line string or any other
valid rfc 2822/5322 email header.
The line with space causes checkpatch to erroneously think that it's in
the content body, as opposed to headers and thus flag a mail header as
an unwrapped long comment line.
Joe Perches [Mon, 8 May 2017 22:55:39 +0000 (15:55 -0700)]
checkpatch: improve EMBEDDED_FUNCTION_NAME test
The existing behavior relies on patch context to identify function
declarations. Add the ability to find function declarations when there
is an open brace in column 1.
This finds function declarations only in specific single line forms
where the function name is on a single line like:
Joe Perches [Mon, 8 May 2017 22:55:36 +0000 (15:55 -0700)]
checkpatch: add ability to find bad uses of vsprintf %p<foo> extensions
%pK was at least once misused at %pk in an out-of-tree module. This
lead to some security concerns. Add the ability to track single and
multiple line statements for misuses of %p<foo>.
Config EXPERIMENTAL has been removed from kernel in 2013 (see commit 3d374d09f16f: "final removal of CONFIG_EXPERIMENTAL"), there is no any
reason to do these checks now.
firmware/Makefile: force recompilation if makefile changes
If you modify the target asm we currently do not force the recompilation
of the firmware files. The target asm is in the firmware/Makefile, peg
this file as a dependency to require re-compilation of firmware targets
when the asm changes.
Revert "lib/test_sort.c: make it explicitly non-modular"
Patch series "lib: add module support to sort tests".
This patch series allows to compile the array-based and linked list sort
test code either to loadable modules, or builtin into the kernel.
It's very valuable to have modular tests, so you can run them just by
insmodding the test modules, instead of needing a separate kernel that
runs them at boot.
It's very valuable to have modular tests, so you can run them just by
insmodding the test modules, instead of needing a separate kernel that
runs them at boot.
Tetsuo Handa [Mon, 8 May 2017 22:55:11 +0000 (15:55 -0700)]
kernel/hung_task.c: defer showing held locks
When I was running my testcase which may block hundreds of threads on fs
locks, I got lockup due to output from debug_show_all_locks() added by
commit b2d4c2edb2e4 ("locking/hung_task: Show all locks").
For example, if 1000 threads were blocked in TASK_UNINTERRUPTIBLE state
and 500 out of 1000 threads hold some lock, debug_show_all_locks() from
for_each_process_thread() loop will report locks held by 500 threads for
1000 times. This is a too much noise.
In order to make sure rcu_lock_break() is called frequently, we should
avoid calling debug_show_all_locks() from for_each_process_thread() loop
because debug_show_all_locks() effectively calls for_each_process_thread()
loop. Let's defer calling debug_show_all_locks() till before panic() or
leaving for_each_process_thread() loop.
jiffies.h: declare jiffies and jiffies_64 with ____cacheline_aligned_in_smp
jiffies_64 is defined in kernel/time/timer.c with
____cacheline_aligned_in_smp, however this macro is not part of the
declaration of jiffies and jiffies_64 in jiffies.h.
As a result clang generates the following warning:
kernel/time/timer.c:57:26: error: section does not match previous declaration [-Werror,-Wsection]
__visible u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
^
include/linux/cache.h:39:36: note: expanded from macro '__cacheline_aligned_in_smp'
^
include/linux/cache.h:34:4: note: expanded from macro '__cacheline_aligned'
__section__(".data..cacheline_aligned")))
^
include/linux/jiffies.h:77:12: note: previous attribute is here
extern u64 __jiffy_data jiffies_64;
^
include/linux/jiffies.h:70:38: note: expanded from macro '__jiffy_data'
Lorenzo Stoakes [Mon, 8 May 2017 22:55:02 +0000 (15:55 -0700)]
drivers/virt/fsl_hypervisor.c: use get_user_pages_unlocked()
Moving from get_user_pages() to get_user_pages_unlocked() simplifies the
code and takes advantage of VM_FAULT_RETRY functionality when faulting
in pages.
Vlastimil Babka [Mon, 8 May 2017 22:54:52 +0000 (15:54 -0700)]
mm, compaction: finish whole pageblock to reduce fragmentation
The main goal of direct compaction is to form a high-order page for
allocation, but it should also help against long-term fragmentation when
possible.
Most lower-than-pageblock-order compactions are for non-movable
allocations, which means that if we compact in a movable pageblock and
terminate as soon as we create the high-order page, it's unlikely that
the fallback heuristics will claim the whole block. Instead there might
be a single unmovable page in a pageblock full of movable pages, and the
next unmovable allocation might pick another pageblock and increase
long-term fragmentation.
To help against such scenarios, this patch changes the termination
criteria for compaction so that the current pageblock is finished even
though the high-order page already exists. Note that it might be
possible that the high-order page formed elsewhere in the zone due to
parallel activity, but this patch doesn't try to detect that.
This is only done with sync compaction, because async compaction is
limited to pageblock of the same migratetype, where it cannot result in
a migratetype fallback. (Async compaction also eagerly skips
order-aligned blocks where isolation fails, which is against the goal of
migrating away as much of the pageblock as possible.)
As a result of this patch, long-term memory fragmentation should be
reduced.
In testing based on 4.9 kernel with stress-highalloc from mmtests
configured for order-4 GFP_KERNEL allocations, this patch has reduced
the number of unmovable allocations falling back to movable pageblocks
by 20%. The number
Vlastimil Babka [Mon, 8 May 2017 22:54:49 +0000 (15:54 -0700)]
mm, compaction: restrict async compaction to pageblocks of same migratetype
The migrate scanner in async compaction is currently limited to
MIGRATE_MOVABLE pageblocks. This is a heuristic intended to reduce
latency, based on the assumption that non-MOVABLE pageblocks are
unlikely to contain movable pages.
However, with the exception of THP's, most high-order allocations are
not movable. Should the async compaction succeed, this increases the
chance that the non-MOVABLE allocations will fallback to a MOVABLE
pageblock, making the long-term fragmentation worse.
This patch attempts to help the situation by changing async direct
compaction so that the migrate scanner only scans the pageblocks of the
requested migratetype. If it's a non-MOVABLE type and there are such
pageblocks that do contain movable pages, chances are that the
allocation can succeed within one of such pageblocks, removing the need
for a fallback. If that fails, the subsequent sync attempt will ignore
this restriction.
In testing based on 4.9 kernel with stress-highalloc from mmtests
configured for order-4 GFP_KERNEL allocations, this patch has reduced
the number of unmovable allocations falling back to movable pageblocks
by 30%. The number of movable allocations falling back is reduced by
12%.
Vlastimil Babka [Mon, 8 May 2017 22:54:40 +0000 (15:54 -0700)]
mm, page_alloc: count movable pages when stealing from pageblock
When stealing pages from pageblock of a different migratetype, we count
how many free pages were stolen, and change the pageblock's migratetype
if more than half of the pageblock was free. This might be too
conservative, as there might be other pages that are not free, but were
allocated with the same migratetype as our allocation requested.
While we cannot determine the migratetype of allocated pages precisely
(at least without the page_owner functionality enabled), we can count
pages that compaction would try to isolate for migration - those are
either on LRU or __PageMovable(). The rest can be assumed to be
MIGRATE_RECLAIMABLE or MIGRATE_UNMOVABLE, which we cannot easily
distinguish. This counting can be done as part of free page stealing
with little additional overhead.
The page stealing code is changed so that it considers free pages plus
pages of the "good" migratetype for the decision whether to change
pageblock's migratetype.
The result should be more accurate migratetype of pageblocks wrt the
actual pages in the pageblocks, when stealing from semi-occupied
pageblocks. This should help the efficiency of page grouping by
mobility.
In testing based on 4.9 kernel with stress-highalloc from mmtests
configured for order-4 GFP_KERNEL allocations, this patch has reduced
the number of unmovable allocations falling back to movable pageblocks
by 47%. The number of movable allocations falling back to other
pageblocks are increased by 55%, but these events don't cause permanent
fragmentation, so the tradeoff should be positive. Later patches also
offset the movable fallback increase to some extent.
Vlastimil Babka [Mon, 8 May 2017 22:54:37 +0000 (15:54 -0700)]
mm, page_alloc: split smallest stolen page in fallback
The __rmqueue_fallback() function is called when there's no free page of
requested migratetype, and we need to steal from a different one.
There are various heuristics to make this event infrequent and reduce
permanent fragmentation. The main one is to try stealing from a
pageblock that has the most free pages, and possibly steal them all at
once and convert the whole pageblock. Precise searching for such
pageblock would be expensive, so instead the heuristics walks the free
lists from MAX_ORDER down to requested order and assumes that the block
with highest-order free page is likely to also have the most free pages
in total.
Chances are that together with the highest-order page, we steal also
pages of lower orders from the same block. But then we still split the
highest order page. This is wasteful and can contribute to
fragmentation instead of avoiding it.
This patch thus changes __rmqueue_fallback() to just steal the page(s)
and put them on the freelist of the requested migratetype, and only
report whether it was successful. Then we pick (and eventually split)
the smallest page with __rmqueue_smallest(). This all happens under
zone lock, so nobody can steal it from us in the process. This should
reduce fragmentation due to fallbacks. At worst we are only stealing a
single highest-order page and waste some cycles by moving it between
lists and then removing it, but fallback is not exactly hot path so that
should not be a concern. As a side benefit the patch removes some
duplicate code by reusing __rmqueue_smallest().
Vlastimil Babka [Mon, 8 May 2017 22:54:33 +0000 (15:54 -0700)]
mm, compaction: remove redundant watermark check in compact_finished()
When detecting whether compaction has succeeded in forming a high-order
page, __compact_finished() employs a watermark check, followed by an own
search for a suitable page in the freelists. This is not ideal for two
reasons:
- The watermark check also searches high-order freelists, but has a
less strict criteria wrt fallback. It's therefore redundant and waste
of cycles. This was different in the past when high-order watermark
check attempted to apply reserves to high-order pages.
- The watermark check might actually fail due to lack of order-0 pages.
Compaction can't help with that, so there's no point in continuing
because of that. It's possible that high-order page still exists and
it terminates.
This patch therefore removes the watermark check. This should save some
cycles and terminate compaction sooner in some cases.
Vlastimil Babka [Mon, 8 May 2017 22:54:30 +0000 (15:54 -0700)]
mm, compaction: reorder fields in struct compact_control
Patch series "try to reduce fragmenting fallbacks", v3.
Last year, Johannes Weiner has reported a regression in page mobility
grouping [1] and while the exact cause was not found, I've come up with
some ways to improve it by reducing the number of allocations falling
back to different migratetype and causing permanent fragmentation.
The series was tested with mmtests stress-highalloc modified to do
GFP_KERNEL order-4 allocations, on 4.9 with "mm, vmscan: fix zone
balance check in prepare_kswapd_sleep" (without that, kcompactd indeed
wasn't woken up) on UMA machine with 4GB memory. There were 5 repeats
of each run, as the extfrag stats are quite volatile (note the stats
below are sums, not averages, as it was less perl hacking for me).
Success rate are the same, already high due to the low allocation order
used, so I'm not including them.
Compaction stats:
(the patches are stacked, and I haven't measured the non-functional-changes
patches separately)
Compaction stats are mostly within noise until patch 4, which decreases
the number of compactions, and migrations. Part of that could be due to
more pageblocks marked as unmovable, and async compaction skipping
those. This changes a bit with patch 7, but not so much. Patch 8
increases free scanner stats and migrations, which comes from the
changed termination criteria. Interestingly number of compactions
decreases - probably the fully compacted pageblock satisfies multiple
subsequent allocations, so it amortizes.
Next comes the extfrag tracepoint, where "fragmenting" means that an
allocation had to fallback to a pageblock of another migratetype which
wasn't fully free (which is almost all of the fallbacks). I have
locally added another tracepoint for "Page steal" into
steal_suitable_fallback() which triggers in situations where we are
allowed to do move_freepages_block(). If we decide to also do
set_pageblock_migratetype(), it's "Pages steal with pageblock" with
break down for which allocation migratetype we are stealing and from
which fallback migratetype. The last part "due to counting" comes from
patch 4 and counts the events where the counting of movable pages
allowed us to change pageblock's migratetype, while the number of free
pages alone wouldn't be enough to cross the threshold.
patch 1 patch 2 patch 3 patch 4 patch 7 patch 8
Page alloc extfrag event 10155066852296810164959156220801372706813140319
Extfrag fragmenting 10149231851702510159040156169251372139113134792
Extfrag fragmenting for unmovable 159504 168500 184177 97835 70625 56948
Extfrag fragmenting unmovable placed with movable 153613 163549 172693 91740 64099 50917
Extfrag fragmenting unmovable placed with reclaim. 5891 4951 11484 6095 6526 6031
Extfrag fragmenting for reclaimable 4738 4829 6345 4822 5640 5378
Extfrag fragmenting reclaimable placed with movable 1836 1902 1851 1579 1739 1760
Extfrag fragmenting reclaimable placed with unmov. 2902 2927 4494 3243 3901 3618
Extfrag fragmenting for movable 998498983436969968518155142681364512613072466
Pages steal 179954 192291 210880 123254 94545 81486
Pages steal with pageblock 22153 18943 20154 33562 29969 33444
Pages steal with pageblock for unmovable 14350 12858 13256 20660 19003 20852
Pages steal with pageblock for unmovable from mov. 12812 11402 11683 19072 17467 19298
Pages steal with pageblock for unmovable from recl. 1538 1456 1573 1588 1536 1554
Pages steal with pageblock for movable 7114 5489 5965 11787 10012 11493
Pages steal with pageblock for movable from unmov. 6885 5291 5541 11179 9525 10885
Pages steal with pageblock for movable from recl. 229 198 424 608 487 608
Pages steal with pageblock for reclaimable 689 596 933 1115 954 1099
Pages steal with pageblock for reclaimable from unmov. 273 219 537 658 547 667
Pages steal with pageblock for reclaimable from mov. 416 377 396 457 407 432
Pages steal with pageblock due to counting 11834 10075 7530
... for unmovable 8993 7381 4616
... for movable 2792 2653 2851
... for reclaimable 49 41 63
What we can see is that "Extfrag fragmenting for unmovable" and "...
placed with movable" drops with almost each patch, which is good as we
are polluting less movable pageblocks with unmovable pages.
The most significant change is patch 4 with movable page counting. On
the other hand it increases "Extfrag fragmenting for movable" by 50%.
"Pages steal" drops though, so these movable allocation fallbacks find
only small free pages and are not allowed to steal whole pageblocks
back. "Pages steal with pageblock" raises, because the patch increases
the chances of pageblock migratetype changes to happen. This affects
all migratetypes.
The summary is that patch 4 is not a clear win wrt these stats, but I
believe that the tradeoff it makes is a good one. There's less
pollution of movable pageblocks by unmovable allocations. There's less
stealing between pageblock, and those that remain have higher chance of
changing migratetype also the pageblock itself, so it should more
faithfully reflect the migratetype of the pages within the pageblock.
The increase of movable allocations falling back to unmovable pageblock
might look dramatic, but those allocations can be migrated by compaction
when needed, and other patches in the series (7-9) improve that aspect.
Patches 7 and 8 continue the trend of reduced unmovable fallbacks and
also reduce the impact on movable fallbacks from patch 4.
While currently there are (mostly by accident) no holes in struct
compact_control (on x86_64), but we are going to add more bool flags, so
place them all together to the end of the structure. While at it, just
order all fields from largest to smallest.
Jon Mason [Mon, 8 May 2017 21:48:35 +0000 (17:48 -0400)]
net: mdio-mux: bcm-iproc: call mdiobus_free() in error path
If an error is encountered in mdio_mux_init(), the error path will call
mdiobus_free(). Since mdiobus_register() has been called prior to
mdio_mux_init(), the bus->state will not be MDIOBUS_UNREGISTERED. This
causes a BUG_ON() in mdiobus_free(). To correct this issue, add an
error path for mdio_mux_init() which calls mdiobus_unregister() prior to
mdiobus_free().
Signed-off-by: Jon Mason <[email protected]> Fixes: 98bc865a1ec8 ("net: mdio-mux: Add MDIO mux driver for iProc SoCs") Acked-by: Florian Fainelli <[email protected]> Signed-off-by: David S. Miller <[email protected]>
ide: don't call memcpy with the same source and destination
The parisc architecture recently reimplemented the memcpy function and
their reimplementation crashed when source and destination overlapped.
The crash happened in the function ide_complete_cmd where memcpy is called
with the same source and destination pointer. According to the C
specification, memcpy behavior is undefined if the source and destination
range overlaps. This patches fixes the undefined behavior.
net: ethernet: ti: cpsw: adjust cpsw fifos depth for fullduplex flow control
When users set flow control using ethtool the bits are set properly in the
CPGMAC_SL MACCONTROL register, but the FIFO depth in the respective Port n
Maximum FIFO Blocks (Pn_MAX_BLKS) registers remains set to the minimum size
reset value. When receive flow control is enabled on a port, the port's
associated FIFO block allocation must be adjusted. The port RX allocation
must increase to accommodate the flow control runout. The TRM recommends
numbers of 5 or 6.
Hence, apply required Port FIFO configuration to
Pn_MAX_BLKS.Pn_TX_MAX_BLKS=0xF and Pn_MAX_BLKS.Pn_RX_MAX_BLKS=0x5 during
interface initialization.
WANG Cong [Mon, 8 May 2017 17:12:13 +0000 (10:12 -0700)]
ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf
For each netns (except init_net), we initialize its null entry
in 3 places:
1) The template itself, as we use kmemdup()
2) Code around dst_init_metrics() in ip6_route_net_init()
3) ip6_route_dev_notify(), which is supposed to initialize it after
loopback registers
Unfortunately the last one still happens in a wrong order because
we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to
net->loopback_dev's idev, thus we have to do that after we add
idev to loopback. However, this notifier has priority == 0 same as
ipv6_dev_notf, and ipv6_dev_notf is registered after
ip6_route_dev_notifier so it is called actually after
ip6_route_dev_notifier. This is similar to commit 2f460933f58e
("ipv6: initialize route null entry in addrconf_init()") which
fixes init_net.
Fix it by picking a smaller priority for ip6_route_dev_notifier.
Also, we have to release the refcnt accordingly when unregistering
loopback_dev because device exit functions are called before subsys
exit functions.
David S. Miller [Mon, 8 May 2017 20:02:23 +0000 (16:02 -0400)]
Merge tag 'mac80211-for-davem-2017-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211
Johannes Berg says:
====================
A couple more fixes:
* don't try to authenticate during reconfiguration, which causes
drivers to get confused
* fix a kernel-doc warning for a recently merged change
* fix MU-MIMO group configuration (relevant only for monitor mode)
* more rate flags fix: remove stray RX_ENC_FLAG_40MHZ
* fix IBSS probe response allocation size
====================
Jim Baxter [Mon, 8 May 2017 12:49:57 +0000 (13:49 +0100)]
net: cdc_ncm: Fix TX zero padding
The zero padding that is added to NTB's does
not zero the memory correctly.
This is because the skb_put modifies the value
of skb_out->len which results in the memset
command not setting any memory to zero as
(ctx->tx_max - skb_out->len) == 0.
I have resolved this by storing the size of
the memory to be zeroed before the skb_put
and using this in the memset call.
Linus Torvalds [Mon, 8 May 2017 19:37:56 +0000 (12:37 -0700)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"ARM:
- HYP mode stub supports kexec/kdump on 32-bit
- improved PMU support
- virtual interrupt controller performance improvements
- support for userspace virtual interrupt controller (slower, but
necessary for KVM on the weird Broadcom SoCs used by the Raspberry
Pi 3)
MIPS:
- basic support for hardware virtualization (ImgTec P5600/P6600/I6400
and Cavium Octeon III)
PPC:
- in-kernel acceleration for VFIO
s390:
- support for guests without storage keys
- adapter interruption suppression
x86:
- usual range of nVMX improvements, notably nested EPT support for
accessed and dirty bits
- emulation of CPL3 CPUID faulting
generic:
- first part of VCPU thread request API
- kvm_stat improvements"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
kvm: nVMX: Don't validate disabled secondary controls
KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick
Revert "KVM: Support vCPU-based gfn->hva cache"
tools/kvm: fix top level makefile
KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING
KVM: Documentation: remove VM mmap documentation
kvm: nVMX: Remove superfluous VMX instruction fault checks
KVM: x86: fix emulation of RSM and IRET instructions
KVM: mark requests that need synchronization
KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
KVM: add explicit barrier to kvm_vcpu_kick
KVM: perform a wake_up in kvm_make_all_cpus_request
KVM: mark requests that do not need a wakeup
KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up
KVM: x86: always use kvm_make_request instead of set_bit
KVM: add kvm_{test,clear}_request to replace {test,clear}_bit
s390: kvm: Cpu model support for msa6, msa7 and msa8
KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK
kvm: better MWAIT emulation for guests
KVM: x86: virtualize cpuid faulting
...
Linus Torvalds [Mon, 8 May 2017 19:32:00 +0000 (12:32 -0700)]
Merge branch 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
"Lots of little things this time:
- allow modules to be autoloaded according to the HWCAP feature bits
(used primarily for crypto modules)
- split module core and init PLT sections, since the core code and
init code could be placed far apart, and the PLT sections need to
be local to the code block.
- three patches from Chris Brandt to allow Cortex-A9 L2 cache
optimisations to be disabled where a SoC didn't wire up the out of
band signals.
- NoMMU compliance fixes, avoiding corruption of vector table which
is not being used at this point, and avoiding possible register
state corruption when switching mode.
- fixmap memory attribute compliance update.
- remove unnecessary locking from update_sections_early()
- ftrace fix for DEBUG_RODATA with !FRAME_POINTER"
* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8672/1: mm: remove tasklist locking from update_sections_early()
ARM: 8671/1: V7M: Preserve registers across switch from Thread to Handler mode
ARM: 8670/1: V7M: Do not corrupt vector table around v7m_invalidate_l1 call
ARM: 8668/1: ftrace: Fix dynamic ftrace with DEBUG_RODATA and !FRAME_POINTER
ARM: 8667/3: Fix memory attribute inconsistencies when using fixmap
ARM: 8663/1: wire up HWCAP/HWCAP2 feature bits to the CPU modalias
ARM: 8666/1: mm: dump: Add domain to output
ARM: 8662/1: module: split core and init PLT sections
ARM: 8661/1: dts: r7s72100: add l2 cache
ARM: 8660/1: shmobile: r7s72100: Enable L2 cache
ARM: 8659/1: l2c: allow CA9 optimizations to be disabled
Linus Torvalds [Mon, 8 May 2017 19:29:46 +0000 (12:29 -0700)]
Merge tag 'xtensa-20170507' of git://github.com/jcmvbkbc/linux-xtensa
Pull Xtensa updates from Max Filippov:
- clearly mark references to spilled register locations with SPILL_SLOT
macros
- clean up xtensa ptrace: use generic tracehooks, move internal kernel
definitions from uapi/asm to asm, make locally-used functions static,
fix code style and alignment
- use command line parameters passed to ISS as kernel command line.
* tag 'xtensa-20170507' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: clean up access to spilled registers locations
xtensa: use generic tracehooks
xtensa: move internal ptrace definitions from uapi/asm to asm
xtensa: clean up xtensa/kernel/ptrace.c
xtensa: drop unused fast_io_protect function
xtensa: use ITLB_HIT_BIT instead of hardcoded number
xtensa: ISS: update kernel command line in platform_setup
xtensa: ISS: add argc/argv simcall definitions
xtensa: ISS: cleanup setup.c
Linus Torvalds [Mon, 8 May 2017 19:24:17 +0000 (12:24 -0700)]
Merge tag 'for-f2fs-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've focused on enhancing performance with regards to
block allocation, GC, and discard/in-place-update IO controls. There
are a bunch of clean-ups as well as minor bug fixes.
Enhancements:
- disable heap-based allocation by default
- issue small-sized discard commands by default
- change the policy of data hotness for logging
- distinguish IOs in terms of size and wbc type
- start SSR earlier to avoid foreground GC
- enhance data structures managing discard commands
- enhance in-place update flow
- add some more fault injection routines
- secure one more xattr entry
Bug fixes:
- calculate victim cost for GC correctly
- remain correct victim segment number for GC
- race condition in nid allocator and initializer
- stale pointer produced by atomic_writes
- fix missing REQ_SYNC for flush commands
- handle missing errors in more corner cases"
* tag 'for-f2fs-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (111 commits)
f2fs: fix a mount fail for wrong next_scan_nid
f2fs: enhance scalability of trace macro
f2fs: relocate inode_{,un}lock in F2FS_IOC_SETFLAGS
f2fs: Make flush bios explicitely sync
f2fs: show available_nids in f2fs/status
f2fs: flush dirty nats periodically
f2fs: introduce CP_TRIMMED_FLAG to avoid unneeded discard
f2fs: allow cpc->reason to indicate more than one reason
f2fs: release cp and dnode lock before IPU
f2fs: shrink size of struct discard_cmd
f2fs: don't hold cmd_lock during waiting discard command
f2fs: nullify fio->encrypted_page for each writes
f2fs: sanity check segment count
f2fs: introduce valid_ipu_blkaddr to clean up
f2fs: lookup extent cache first under IPU scenario
f2fs: reconstruct code to write a data page
f2fs: introduce __wait_discard_cmd
f2fs: introduce __issue_discard_cmd
f2fs: enable small discard by default
f2fs: delay awaking discard thread
...
stmmaceth 0000:00:14.6 eth0: Link is Up - 100Mbps/Full - flow control off
IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: stmmac_xmit+0xf1/0x1080
Fix this by adding necessary settings.
P.S. I split fix to three patches according to what each of them adds.
====================