attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with const
attribute_group. So mark the non-const structs as const.
Roman Gushchin [Wed, 6 Sep 2017 23:21:50 +0000 (16:21 -0700)]
cgroup: revert fa06235b8eb0 ("cgroup: reset css on destruction")
Commit fa06235b8eb0 ("cgroup: reset css on destruction") caused
css_reset callback to be called from the offlining path. Although it
solves the problem mentioned in the commit description ("For instance,
memory cgroup needs to reset memory.low, otherwise pages charged to a
dead cgroup might never get reclaimed."), generally speaking, it's not
correct.
An offline cgroup can still be a resource domain, and we shouldn't grant
it more resources than it had before deletion.
For instance, if an offline memory cgroup has dirty pages, we should
still imply i/o limits during writeback.
The css_reset callback is designed to return the cgroup state into the
original state, that means reset all limits and counters. It's
spomething different from the offlining, and we shouldn't use it from
the offlining path. Instead, we should adjust necessary settings from
the per-controller css_offline callbacks (e.g. reset memory.low).
Roman Gushchin [Wed, 6 Sep 2017 23:21:47 +0000 (16:21 -0700)]
mm, memcg: reset memory.low during memcg offlining
A removed memory cgroup with a defined memory.low and some belonging
pagecache has very low chances to be freed.
If a cgroup has been removed, there is likely no memory pressure inside
the cgroup, and the pagecache is protected from the external pressure by
the defined low limit. The cgroup will be freed only after the reclaim
of all belonging pages. And it will not happen until there are any
reclaimable memory in the system. That means, there is a good chance,
that a cold pagecache will reside in the memory for an undefined amount
of time, wasting system resources.
This problem was fixed earlier by fa06235b8eb0 ("cgroup: reset css on
destruction"), but it's not a best way to do it, as we can't really
reset all limits/counters during cgroup offlining.
Jan Kara [Wed, 6 Sep 2017 23:21:37 +0000 (16:21 -0700)]
fs: use pagevec_lookup_range() in page_cache_seek_hole_data()
We want only pages from given range in page_cache_seek_hole_data(). Use
pagevec_lookup_range() instead of pagevec_lookup() and remove
unnecessary code.
Note that the check for getting less pages than desired can be removed
because index gets updated by pagevec_lookup_range().
Jan Kara [Wed, 6 Sep 2017 23:21:27 +0000 (16:21 -0700)]
ext4: use pagevec_lookup_range() in ext4_find_unwritten_pgoff()
Use pagevec_lookup_range() in ext4_find_unwritten_pgoff() since we are
interested only in pages in the given range. Simplify the logic as a
result of not getting pages out of range and index getting automatically
advanced.
Jan Kara [Wed, 6 Sep 2017 23:21:24 +0000 (16:21 -0700)]
fs: fix performance regression in clean_bdev_aliases()
Commit e64855c6cfaa ("fs: Add helper to clean bdev aliases under a bh
and use it") added a wrapper for clean_bdev_aliases() that invalidates
bdev aliases underlying a single buffer head.
However this has caused a performance regression for bonnie++ benchmark
on ext4 filesystem when delayed allocation is turned off (ext3 mode) -
average of 3 runs:
The reason for this regression is that clean_bdev_aliases() is slower
when called for a single block because pagevec_lookup() it uses will end
up iterating through the radix tree until it finds a page (which may
take a while) but we are only interested whether there's a page at a
particular index.
Fix the problem by using pagevec_lookup_range() instead which avoids the
needless iteration.
Jan Kara [Wed, 6 Sep 2017 23:21:21 +0000 (16:21 -0700)]
mm: implement find_get_pages_range()
Implement a variant of find_get_pages() that stops iterating at given
index. This may be substantial performance gain if the mapping is
sparse. See following commit for details. Furthermore lots of users of
this function (through pagevec_lookup()) actually want a range lookup
and all of them are currently open-coding this.
Also create corresponding pagevec_lookup_range() function.
Jan Kara [Wed, 6 Sep 2017 23:21:18 +0000 (16:21 -0700)]
mm: make pagevec_lookup() update index
Make pagevec_lookup() (and underlying find_get_pages()) update index to
the next page where iteration should continue. Most callers want this
and also pagevec_lookup_tag() already does this.
Jan Kara [Wed, 6 Sep 2017 23:21:15 +0000 (16:21 -0700)]
fscache: remove unused ->now_uncached callback
Patch series "Ranged pagevec lookup", v2.
In this series I make pagevec_lookup() update the index (to be
consistent with pagevec_lookup_tag() and also as a preparation for
ranged lookups), provide ranged variant of pagevec_lookup() and use it
in places where it makes sense. This not only removes some common code
but is also a measurable performance win for some use cases (see patch
4/10) where radix tree is sparse and searching & grabing of a page after
the end of the range has measurable overhead.
Michal Hocko [Wed, 6 Sep 2017 23:21:11 +0000 (16:21 -0700)]
mm, vmscan: do not loop on too_many_isolated for ever
Tetsuo Handa has reported[1][2][3] that direct reclaimers might get
stuck in too_many_isolated loop basically for ever because the last few
pages on the LRU lists are isolated by the kswapd which is stuck on fs
locks when doing the pageout or slab reclaim. This in turn means that
there is nobody to actually trigger the oom killer and the system is
basically unusable.
too_many_isolated has been introduced by commit 35cd78156c49 ("vmscan:
throttle direct reclaim when too many pages are isolated already") to
prevent from pre-mature oom killer invocations because back then no
reclaim progress could indeed trigger the OOM killer too early.
But since the oom detection rework in commit 0a0337e0d1d1 ("mm, oom:
rework oom detection") the allocation/reclaim retry loop considers all
the reclaimable pages and throttles the allocation at that layer so we
can loosen the direct reclaim throttling.
Make shrink_inactive_list loop over too_many_isolated bounded and
returns immediately when the situation hasn't resolved after the first
sleep.
Replace congestion_wait by a simple schedule_timeout_interruptible
because we are not really waiting on the IO congestion in this path.
Please note that this patch can theoretically cause the OOM killer to
trigger earlier while there are many pages isolated for the reclaim
which makes progress only very slowly. This would be obvious from the
oom report as the number of isolated pages are printed there. If we
ever hit this should_reclaim_retry should consider those numbers in the
evaluation in one way or another.
zsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage is not inuse
Getting -EBUSY from zs_page_migrate will make migration slow (retry) or
fail (zs_page_putback will schedule_work free_work, but it cannot ensure
the success).
I noticed this issue because my Kernel patched
(https://lkml.org/lkml/2014/5/28/113) that will remove retry in
__alloc_contig_migrate_range.
This retry will handle the -EBUSY because it will re-isolate the page
and re-call migrate_pages. Without it will make cma_alloc fail at once
with -EBUSY.
According to the review from Minchan Kim in
https://lkml.org/lkml/2014/5/28/113, I update the patch to skip
unnecessary loops but not return -EBUSY if zspage is not inuse.
Following is what I got with highalloc-performance in a vbox with 2 cpu
1G memory 512 zram as swap. And the swappiness is set to 100.
ori ne
orig new
Minor Faults 5080511350830235
Major Faults 43918 56530
Swap Ins 42087 55680
Swap Outs 89718 104700
Allocation stalls 0 0
DMA allocs 57787 52364
DMA32 allocs 4796459948043563
Normal allocs 0 0
Movable allocs 0 0
Direct pages scanned 45493 23167
Kswapd pages scanned 15652221725078
Kswapd pages reclaimed 13422221503037
Direct pages reclaimed 45615 25186
Kswapd efficiency 85% 87%
Kswapd velocity 1897.101 1949.042
Direct efficiency 100% 108%
Direct velocity 55.139 26.175
Percentage direct scans 2% 1%
Zone normal velocity 1952.240 1975.217
Zone dma32 velocity 0.000 0.000
Zone dma velocity 0.000 0.000
Page writes by reclaim 89764.000 105233.000
Page writes file 46 533
Page writes anon 89718 104700
Page reclaim immediate 21457 3699
Sector Reads 32596883441368
Sector Writes 36672523754836
Page rescued immediate 0 0
Slabs scanned 10428721160855
Direct inode steals 8042 10089
Kswapd inode steals 54295 29170
Kswapd skipped wait 0 0
THP fault alloc 175 154
THP collapse alloc 226 289
THP splits 0 0
THP fault fallback 11 14
THP collapse fail 3 2
Compaction stalls 536 646
Compaction success 322 358
Compaction failures 214 288
Page migrate success 119608 111063
Page migrate failure 2723 2593
Compaction pages isolated 250179 232652
Compaction migrate scanned 91318329942306
Compaction free scanned 20932722613998
Compaction cost 192 189
NUMA alloc hit 4712455547193990
NUMA alloc miss 0 0
NUMA interleave hit 0 0
NUMA alloc local 4712455547193990
NUMA base PTE updates 0 0
NUMA huge PMD updates 0 0
NUMA page range updates 0 0
NUMA hint faults 0 0
NUMA hint local faults 0 0
NUMA hint local percent 100 100
NUMA pages migrated 0 0
AutoNUMA cost 0% 0%
mm: always flush VMA ranges affected by zap_page_range
Nadav Amit report zap_page_range only specifies that the caller protect
the VMA list but does not specify whether it is held for read or write
with callers using either. madvise holds mmap_sem for read meaning that
a parallel zap operation can unmap PTEs which are then potentially
skipped by madvise which potentially returns with stale TLB entries
present. While the API could be extended, it would be a difficult API
to use. This patch causes zap_page_range() to always consider flushing
the full affected range. For small ranges or sparsely populated
mappings, this may result in one additional spurious TLB flush. For
larger ranges, it is possible that the TLB has already been flushed and
the overhead is negligible. Either way, this approach is safer overall
and avoids stale entries being present when madvise returns.
This can be illustrated with the following program provided by Nadav
Amit and slightly modified. With the patch applied, it has an exit code
of 0 indicating a stale TLB entry did not leak to userspace.
---8<---
volatile int sync_step = 0;
volatile char *p;
static inline unsigned long rdtsc()
{
unsigned long hi, lo;
__asm__ __volatile__ ("rdtsc" : "=a"(lo), "=d"(hi));
return lo | (hi << 32);
}
static inline void wait_rdtsc(unsigned long cycles)
{
unsigned long tsc = rdtsc();
mm/hugetlb.c: make huge_pte_offset() consistent and document behaviour
When walking the page tables to resolve an address that points to
!p*d_present() entry, huge_pte_offset() returns inconsistent values
depending on the level of page table (PUD or PMD).
It returns NULL in the case of a PUD entry while in the case of a PMD
entry, it returns a pointer to the page table entry.
A similar inconsitency exists when handling swap entries - returns NULL
for a PUD entry while a pointer to the pte_t is retured for the PMD
entry.
Update huge_pte_offset() to make the behaviour consistent - return a
pointer to the pte_t for hugepage or swap entries. Only return NULL in
instances where we have a p*d_none() entry and the size parameter
doesn't match the hugepage size at this level of the page table.
Document the behaviour to clarify the expected behaviour of this
function. This is to set clear semantics for architecture specific
implementations of huge_pte_offset().
Discussions on the arm64 implementation of huge_pte_offset()
(http://www.spinics.net/lists/linux-mm/msg133699.html) showed that there
is benefit from returning a pte_t* in the case of p*d_none().
The fault handling code in hugetlb_fault() can handle p*d_none() entries
and saves an extra round trip to huge_pte_alloc(). Other callers of
huge_pte_offset() should be ok as well.
These functions are the only bits of generic code that use
{pud,pmd}_pfn() without checking for CONFIG_TRANSPARENT_HUGEPAGE. This
works fine on x86, the only arch with devmap support, since the *_pfn()
functions are always defined there, but this isn't true for every
architecture.
Mike Kravetz [Wed, 6 Sep 2017 23:20:55 +0000 (16:20 -0700)]
mm/mremap: fail map duplication attempts for private mappings
mremap will attempt to create a 'duplicate' mapping if old_size == 0 is
specified. In the case of private mappings, mremap will actually create
a fresh separate private mapping unrelated to the original. This does
not fit with the design semantics of mremap as the intention is to
create a new mapping based on the original.
Therefore, return EINVAL in the case where an attempt is made to
duplicate a private mapping. Also, print a warning message (once) if
such an attempt is made.
mm, page_owner: don't grab zone->lock for init_pages_in_zone()
init_pages_in_zone() is run under zone->lock, which means a long lock
time and disabled interrupts on large machines. This is currently not
an issue since it runs early in boot, but a later patch will change
that.
However, like other pfn scanners, we don't actually need zone->lock even
when other cpus are running. The only potentially dangerous operation
here is reading bogus buddy page owner due to race, and we already know
how to handle that. The worst that can happen is that we skip some
early allocated pages, which should not affect the debugging power of
page_owner noticeably.
mm, page_ext: periodically reschedule during page_ext_init()
page_ext_init() can take long on large machines, so add a cond_resched()
point after each section is processed. This will allow moving the init
to a later point at boot without triggering lockup reports.
In init_pages_in_zone() we currently use the generic set_page_owner()
function to initialize page_owner info for early allocated pages. This
means we needlessly do lookup_page_ext() twice for each page, and more
importantly save_stack(), which has to unwind the stack and find the
corresponding stack depot handle. Because the stack is always the same
for the initialization, unwind it once in init_pages_in_zone() and reuse
the handle. Also avoid the repeated lookup_page_ext().
This can significantly reduce boot times with page_owner=on on large
machines, especially for kernels built without frame pointer, where the
stack unwinding is noticeably slower.
Michal Hocko [Wed, 6 Sep 2017 23:20:41 +0000 (16:20 -0700)]
mm, sparse, page_ext: drop ugly N_HIGH_MEMORY branches for allocations
Commit f52407ce2dea ("memory hotplug: alloc page from other node in
memory online") has introduced N_HIGH_MEMORY checks to only use NUMA
aware allocations when there is some memory present because the
respective node might not have any memory yet at the time and so it
could fail or even OOM.
Things have changed since then though. Zonelists are now always
initialized before we do any allocations even for hotplug (see 959ecc48fc75 ("mm/memory_hotplug.c: fix building of node hotplug
zonelist")).
Therefore these checks are not really needed. In fact caller of the
allocator should never care about whether the node is populated because
that might change at any time.
Michal Hocko [Wed, 6 Sep 2017 23:20:37 +0000 (16:20 -0700)]
mm, memory_hotplug: get rid of zonelists_mutex
zonelists_mutex was introduced by commit 4eaf3f64397c ("mem-hotplug: fix
potential race while building zonelist for new populated zone") to
protect zonelist building from races. This is no longer needed though
because both memory online and offline are fully serialized. New users
have grown since then.
Notably setup_per_zone_wmarks wants to prevent from races between memory
hotplug, khugepaged setup and manual min_free_kbytes update via sysctl
(see cfd3da1e49bb ("mm: Serialize access to min_free_kbytes"). Let's
add a private lock for that purpose. This will not prevent from seeing
halfway through memory hotplug operation but that shouldn't be a big
deal becuse memory hotplug will update watermarks explicitly so we will
eventually get a full picture. The lock just makes sure we won't race
when updating watermarks leading to weird results.
Also __build_all_zonelists manipulates global data so add a private lock
for it as well. This doesn't seem to be necessary today but it is more
robust to have a lock there.
While we are at it make sure we document that memory online/offline
depends on a full serialization either via mem_hotplug_begin() or
device_lock.
Michal Hocko [Wed, 6 Sep 2017 23:20:34 +0000 (16:20 -0700)]
mm, page_alloc: remove stop_machine from build_all_zonelists
build_all_zonelists has been (ab)using stop_machine to make sure that
zonelists do not change while somebody is looking at them. This is is
just a gross hack because a) it complicates the context from which we
can call build_all_zonelists (see 3f906ba23689 ("mm/memory-hotplug:
switch locking to a percpu rwsem")) and b) is is not really necessary
especially after "mm, page_alloc: simplify zonelist initialization" and
c) it doesn't really provide the protection it claims (see below).
Updates of the zonelists happen very seldom, basically only when a zone
becomes populated during memory online or when it loses all the memory
during offline. A racing iteration over zonelists could either miss a
zone or try to work on one zone twice. Both of these are something we
can live with occasionally because there will always be at least one
zone visible so we are not likely to fail allocation too easily for
example.
Please note that the original stop_machine approach doesn't really
provide a better exclusion because the iteration might be interrupted
half way (unless the whole iteration is preempt disabled which is not
the case in most cases) so the some zones could still be seen twice or a
zone missed.
I have run the pathological online/offline of the single memblock in the
movable zone while stressing the same small node with some memory
pressure.
Node 1, zone DMA
pages free 0
min 0
low 0
high 0
spanned 0
present 0
managed 0
protection: (0, 943, 943, 943)
Node 1, zone DMA32
pages free 227310
min 8294
low 10367
high 12440
spanned 262112
present 262112
managed 241436
protection: (0, 0, 0, 0)
Node 1, zone Normal
pages free 0
min 0
low 0
high 0
spanned 0
present 0
managed 0
protection: (0, 0, 0, 1024)
Node 1, zone Movable
pages free 32722
min 85
low 117
high 149
spanned 32768
present 32768
managed 32768
protection: (0, 0, 0, 0)
root@test1:/sys/devices/system/node/node1# while true
do
echo offline > memory34/state
echo online_movable > memory34/state
done
root@test1:/mnt/data/test/linux-3.7-rc5# numactl --preferred=1 make -j4
and it survived without any unexpected behavior. While this is not
really a great testing coverage it should exercise the allocation path
quite a lot.
Michal Hocko [Wed, 6 Sep 2017 23:20:30 +0000 (16:20 -0700)]
mm, page_alloc: simplify zonelist initialization
build_zonelists gradually builds zonelists from the nearest to the most
distant node. As we do not know how many populated zones we will have
in each node we rely on the _zoneref to terminate initialized part of
the zonelist by a NULL zone. While this is functionally correct it is
quite suboptimal because we cannot allow updaters to race with zonelists
users because they could see an empty zonelist and fail the allocation
or hit the OOM killer in the worst case.
We can do much better, though. We can store the node ordering into an
already existing node_order array and then give this array to
build_zonelists_in_node_order and do the whole initialization at once.
zonelists consumers still might see halfway initialized state but that
should be much more tolerateable because the list will not be empty and
they would either see some zone twice or skip over some zone(s) in the
worst case which shouldn't lead to immediate failures.
While at it let's simplify build_zonelists_node which is rather
confusing now. It gets an index into the zoneref array and returns the
updated index for the next iteration. Let's rename the function to
build_zonerefs_node to better reflect its purpose and give it zoneref
array to update. The function doesn't the index anymore. It just
returns the number of added zones so that the caller can advance the
zonered array start for the next update.
This patch alone doesn't introduce any functional change yet, though, it
is merely a preparatory work for later changes.
Michal Hocko [Wed, 6 Sep 2017 23:20:27 +0000 (16:20 -0700)]
mm, memory_hotplug: remove explicit build_all_zonelists from try_online_node
try_online_node calls hotadd_new_pgdat which already calls
build_all_zonelists. So the additional call is redundant. Even though
hotadd_new_pgdat will only initialize zonelists of the new node this is
the right thing to do because such a node doesn't have any memory so
other zonelists would ignore all the zones from this node anyway.
Michal Hocko [Wed, 6 Sep 2017 23:20:24 +0000 (16:20 -0700)]
mm, memory_hotplug: drop zone from build_all_zonelists
build_all_zonelists gets a zone parameter to initialize zone's pagesets.
There is only a single user which gives a non-NULL zone parameter and
that one doesn't really need the rest of the build_all_zonelists (see
commit 6dcd73d7011b ("memory-hotplug: allocate zone's pcp before
onlining pages")).
Therefore remove setup_zone_pageset from build_all_zonelists and call it
from its only user directly. This will also remove a pointless zonlists
rebuilding which is always good.
Michal Hocko [Wed, 6 Sep 2017 23:20:20 +0000 (16:20 -0700)]
mm, page_alloc: do not set_cpu_numa_mem on empty nodes initialization
__build_all_zonelists reinitializes each online cpu local node for
CONFIG_HAVE_MEMORYLESS_NODES. This makes sense because previously
memory less nodes could gain some memory during memory hotplug and so
the local node should be changed for CPUs close to such a node. It
makes less sense to do that unconditionally for a newly creaded NUMA
node which is still offline and without any memory.
Let's also simplify the cpu loop and use for_each_online_cpu instead of
an explicit cpu_online check for all possible cpus.
Michal Hocko [Wed, 6 Sep 2017 23:20:17 +0000 (16:20 -0700)]
mm, page_alloc: remove boot pageset initialization from memory hotplug
boot_pageset is a boot time hack which gets superseded by normal
pagesets later in the boot process. It makes zero sense to reinitialize
it again and again during memory hotplug.
Michal Hocko [Wed, 6 Sep 2017 23:20:13 +0000 (16:20 -0700)]
mm, page_alloc: rip out ZONELIST_ORDER_ZONE
Patch series "cleanup zonelists initialization", v1.
This is aimed at cleaning up the zonelists initialization code we have
but the primary motivation was bug report [2] which got resolved but the
usage of stop_machine is just too ugly to live. Most patches are
straightforward but 3 of them need a special consideration.
Patch 1 removes zone ordered zonelists completely. I am CCing linux-api
because this is a user visible change. As I argue in the patch
description I do not think we have a strong usecase for it these days.
I have kept sysctl in place and warn into the log if somebody tries to
configure zone lists ordering. If somebody has a real usecase for it we
can revert this patch but I do not expect anybody will actually notice
runtime differences. This patch is not strictly needed for the rest but
it made patch 6 easier to implement.
Patch 7 removes stop_machine from build_all_zonelists without adding any
special synchronization between iterators and updater which I _believe_
is acceptable as explained in the changelog. I hope I am not missing
anything.
Patch 8 then removes zonelists_mutex which is kind of ugly as well and
not really needed AFAICS but a care should be taken when double checking
my thinking.
This patch (of 9):
Supporting zone ordered zonelists costs us just a lot of code while the
usefulness is arguable if existent at all. Mel has already made node
ordering default on 64b systems. 32b systems are still using
ZONELIST_ORDER_ZONE because it is considered better to fallback to a
different NUMA node rather than consume precious lowmem zones.
This argument is, however, weaken by the fact that the memory reclaim
has been reworked to be node rather than zone oriented. This means that
lowmem requests have to skip over all highmem pages on LRUs already and
so zone ordering doesn't save the reclaim time much. So the only
advantage of the zone ordering is under a light memory pressure when
highmem requests do not ever hit into lowmem zones and the lowmem
pressure doesn't need to reclaim.
Considering that 32b NUMA systems are rather suboptimal already and it
is generally advisable to use 64b kernel on such a HW I believe we
should rather care about the code maintainability and just get rid of
ZONELIST_ORDER_ZONE altogether. Keep systcl in place and warn if
somebody tries to set zone ordering either from kernel command line or
the sysctl.
Minchan Kim [Wed, 6 Sep 2017 23:20:07 +0000 (16:20 -0700)]
zram: read page from backing device
This patch enables read IO from backing device. For the feature, it
implements two IO read functions to transfer data from backing storage.
One is asynchronous IO function and other is synchronous one.
A reason I need synchrnous IO is due to partial write which need to
complete read IO before the overwriting partial data.
We can make the partial IO's case asynchronous, too but at the moment, I
don't feel adding more complexity to support such rare use cases so want
to go with simple.
Minchan Kim [Wed, 6 Sep 2017 23:20:03 +0000 (16:20 -0700)]
zram: write incompressible pages to backing device
This patch enables write IO to transfer data to backing device. For
that, it implements write_to_bdev function which creates new bio and
chaining with parent bio to make the parent bio asynchrnous.
For rw_page which don't have parent bio, it submit owned bio and handle
IO completion by zram_page_end_io.
Also, this patch defines new flag ZRAM_WB to mark written page for later
read IO.
Minchan Kim [Wed, 6 Sep 2017 23:20:00 +0000 (16:20 -0700)]
zram: identify asynchronous IO's return value
For upcoming asynchronous IO like writeback, zram_rw_page should be
aware of that whether requested IO was completed or submitted
successfully, otherwise error.
For the goal, zram_bvec_rw has three return values.
-errno: returns error number
0: IO request is done synchronously
1: IO request is issued successfully.
Minchan Kim [Wed, 6 Sep 2017 23:19:57 +0000 (16:19 -0700)]
zram: add free space management in backing device
With backing device, zram needs management of free space of backing
device.
This patch adds bitmap logic to manage free space which is very naive.
However, it would be simple enough as considering uncompressible pages's
frequenty in zram.
Minchan Kim [Wed, 6 Sep 2017 23:19:44 +0000 (16:19 -0700)]
zram: clean up duplicated codes in __zram_bvec_write
Patch series "writeback incompressible pages to storage", v1.
zRam is useful for memory saving with compressible pages but sometime,
workload can be changed and system has lots of incompressible pages
which is very harmful for zram.
This patch supports writeback feature of zram so admin can set up a
block device and with it, zram can save the memory via writing out the
incompressile pages once it found it's incompressible pages (1/4 comp
ratio) instead of keeping the page in memory.
[1-3] is just clean up and [4-8] is step by step feature enablement.
[4-8] is logically not bisectable(ie, logical unit separation)
although I tried to compiled out without breaking but I think it would
be better to review.
This patch (of 9):
__zram_bvec_write has some of duplicated logic for zram meta data
handling of same_page|compressed_page. This patch aims to clean it up
without behavior change.
Michal Hocko [Wed, 6 Sep 2017 23:19:40 +0000 (16:19 -0700)]
mm, memory_hotplug: remove zone restrictions
Historically we have enforced that any kernel zone (e.g ZONE_NORMAL) has
to precede the Movable zone in the physical memory range. The purpose
of the movable zone is, however, not bound to any physical memory
restriction. It merely defines a class of migrateable and reclaimable
memory.
There are users (e.g. CMA) who might want to reserve specific physical
memory ranges for their own purpose. Moreover our pfn walkers have to
be prepared for zones overlapping in the physical range already because
we do support interleaving NUMA nodes and therefore zones can interleave
as well. This means we can allow each memory block to be associated
with a different zone.
Loosen the current onlining semantic and allow explicit onlining type on
any memblock. That means that online_{kernel,movable} will be allowed
regardless of the physical address of the memblock as long as it is
offline of course. This might result in moveble zone overlapping with
other kernel zones. Default onlining then becomes a bit tricky but
still sensible. echo online > memoryXY/state will online the given
block to
1) the default zone if the given range is outside of any zone
2) the enclosing zone if such a zone doesn't interleave with
any other zone
3) the default zone if more zones interleave for this range
where default zone is movable zone only if movable_node is enabled
otherwise it is a kernel zone.
Here is an example of the semantic with (movable_node is not present but
it work in an analogous way). We start with following memblocks, all of
them offline:
As we can see all other blocks can still be onlined both into Normal and
Movable zones and the Normal is default because the Movable zone spans
only block37 now.
root@test1:/sys/devices/system/node/node1# echo online_movable > memory41/state
memory34/valid_zones:Normal
memory35/valid_zones:Normal Movable
memory36/valid_zones:Normal Movable
memory37/valid_zones:Movable
memory38/valid_zones:Movable Normal
memory39/valid_zones:Movable Normal
memory40/valid_zones:Movable Normal
memory41/valid_zones:Movable
Now the default zone for blocks 37-41 has changed because movable zone
spans that range.
Implementation wise the change is quite straightforward. We can get rid
of allow_online_pfn_range altogether. online_pages allows only offline
nodes already. The original default_zone_for_pfn will become
default_kernel_zone_for_pfn. New default_zone_for_pfn implements the
above semantic. zone_for_pfn_range is slightly reorganized to implement
kernel and movable online type explicitly and MMOP_ONLINE_KEEP becomes a
catch all default behavior.
Michal Hocko [Wed, 6 Sep 2017 23:19:37 +0000 (16:19 -0700)]
mm, memory_hotplug: display allowed zones in the preferred ordering
Prior to commit f1dd2cd13c4b ("mm, memory_hotplug: do not associate
hotadded memory to zones until online") we used to allow to change the
valid zone types of a memory block if it is adjacent to a different zone
type.
This fact was reflected in memoryNN/valid_zones by the ordering of
printed zones. The first one was default (echo online > memoryNN/state)
and the other one could be onlined explicitly by online_{movable,kernel}.
This behavior was removed by the said patch and as such the ordering was
not all that important. In most cases a kernel zone would be default
anyway. The only exception is movable_node handled by "mm,
memory_hotplug: support movable_node for hotpluggable nodes".
Let's reintroduce this behavior again because later patch will remove
the zone overlap restriction and so user will be allowed to online
kernel resp. movable block regardless of its placement. Original
behavior will then become significant again because it would be
non-trivial for users to see what is the default zone to online into.
Implementation is really simple. Pull out zone selection out of
move_pfn_range into zone_for_pfn_range helper and use it in
show_valid_zones to display the zone for default onlining and then both
kernel and movable if they are allowed. Default online zone is not
duplicated.
Wei Yang [Wed, 6 Sep 2017 23:19:33 +0000 (16:19 -0700)]
mm/memory_hotplug: just build zonelist for newly added node
Commit 9adb62a5df9c ("mm/hotplug: correctly setup fallback zonelists
when creating new pgdat") tries to build the correct zonelist for a
newly added node, while it is not necessary to rebuild it for already
exist nodes.
In build_zonelists(), it will iterate on nodes with memory. For a newly
added node, it will have memory until node_states_set_node() is called
in online_pages().
This patch avoids rebuilding the zonelists for already existing nodes.
build_zonelists_node() uses managed_zone(zone) checks, so it should not
include empty zones anyway. So effectively we avoid some pointless work
under stop_machine().
Chris Wilson [Wed, 6 Sep 2017 23:19:30 +0000 (16:19 -0700)]
drm/i915: wire up shrinkctl->nr_scanned
shrink_slab() allows us to report back the number of objects we
successfully scanned (out of the target shrinkctl->nr_to_scan). As
report the number of pages owned by each GEM object as a separate item
to the shrinker, we cannot precisely control the number of shrinker
objects we scan on each pass; and indeed may free more than requested.
If we fail to tell the shrinker about the number of objects we process,
it will continue to hold a grudge against us as any objects left
unscanned are added to the next reclaim -- and so we will keep on
"unfairly" shrinking our own slab in comparison to other slabs.
Chris Wilson [Wed, 6 Sep 2017 23:19:26 +0000 (16:19 -0700)]
mm: track actual nr_scanned during shrink_slab()
Some shrinkers may only be able to free a bunch of objects at a time,
and so free more than the requested nr_to_scan in one pass.
Whilst other shrinkers may find themselves even unable to scan as many
objects as they counted, and so underreport. Account for the extra
freed/scanned objects against the total number of objects we intend to
scan, otherwise we may end up penalising the slab far more than
intended. Similarly, we want to add the underperforming scan to the
deferred pass so that we try harder and harder in future passes.
Alexander Popov [Wed, 6 Sep 2017 23:19:22 +0000 (16:19 -0700)]
mm/slub.c: add a naive detection of double free or corruption
Add an assertion similar to "fasttop" check in GNU C Library allocator
as a part of SLAB_FREELIST_HARDENED feature. An object added to a
singly linked freelist should not point to itself. That helps to detect
some double free errors (e.g. CVE-2017-2636) without slub_debug and
KASAN.
This SLUB free list pointer obfuscation code is modified from Brad
Spengler/PaX Team's code in the last public patch of grsecurity/PaX
based on my understanding of the code. Changes or omissions from the
original code are mine and don't reflect the original grsecurity/PaX
code.
This adds a per-cache random value to SLUB caches that is XORed with
their freelist pointer address and value. This adds nearly zero
overhead and frustrates the very common heap overflow exploitation
method of overwriting freelist pointers.
A recent example of the attack is written up here:
- free_kmem_cache_nodes() frees the cache node before nulling out a
reference to it
- init_kmem_cache_nodes() publishes the cache node before initializing
it
Neither of these matter at runtime because the cache nodes cannot be
looked up by any other thread. But it's neater and more consistent to
reorder these.
There is code duplication between sec_name() and sech_name(). Simplify
sec_name() by re-using sech_name(). Also, move them up to remove the
forward declaration of sec_name().
Ross Zwisler [Wed, 6 Sep 2017 23:18:54 +0000 (16:18 -0700)]
dax: explain how read(2)/write(2) addresses are validated
Add a comment explaining how the user addresses provided to read(2) and
write(2) are validated in the DAX I/O path.
We call dax_copy_from_iter() or copy_to_iter() on these without calling
access_ok() first in the DAX code, and there was a concern that the user
might be able to read/write to arbitrary kernel addresses with this
path.
Ross Zwisler [Wed, 6 Sep 2017 23:18:51 +0000 (16:18 -0700)]
dax: move all DAX radix tree defs to fs/dax.c
Now that we no longer insert struct page pointers in DAX radix trees the
page cache code no longer needs to know anything about DAX exceptional
entries. Move all the DAX exceptional entry definitions from dax.h to
fs/dax.c.
Ross Zwisler [Wed, 6 Sep 2017 23:18:43 +0000 (16:18 -0700)]
dax: use common 4k zero page for dax mmap reads
When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree.
This has three major drawbacks:
1) It consumes memory unnecessarily. For every 4k page that is read via
a DAX mmap() over a hole, we allocate a new page cache page. This
means that if you read 1GiB worth of pages, you end up using 1GiB of
zeroed memory. This is easily visible by looking at the overall
memory consumption of the system or by looking at /proc/[pid]/smaps:
2) It is slower than using a common zero page because each page fault
has more work to do. Instead of just inserting a common zero page we
have to allocate a page cache page, zero it, and then insert it. Here
are the average latencies of dax_load_hole() as measured by ftrace on
a random test box:
Old method, using zeroed page cache pages: 3.4 us
New method, using the common 4k zero page: 0.8 us
This was the average latency over 1 GiB of sequential reads done by
this simple fio script:
3) The fact that we had to check for both DAX exceptional entries and
for page cache pages in the radix tree made the DAX code more
complex.
Solve these issues by following the lead of the DAX PMD code and using a
common 4k zero page instead. As with the PMD code we will now insert a
DAX exceptional entry into the radix tree instead of a struct page
pointer which allows us to remove all the special casing in the DAX
code.
Note that we do still pretty aggressively check for regular pages in the
DAX radix tree, especially where we take action based on the bits set in
the page. If we ever find a regular page in our radix tree now that
most likely means that someone besides DAX is inserting pages (which has
happened lots of times in the past), and we want to find that out early
and fail loudly.
This solution also removes the extra memory consumption. Here is that
same /proc/[pid]/smaps after 1GiB of reading from a hole with the new
code:
Overall system memory consumption is similarly improved.
Another major change is that we remove dax_pfn_mkwrite() from our fault
flow, and instead rely on the page fault itself to make the PTE dirty
and writeable. The following description from the patch adding the
vm_insert_mixed_mkwrite() call explains this a little more:
"To be able to use the common 4k zero page in DAX we need to have our
PTE fault path look more like our PMD fault path where a PTE entry
can be marked as dirty and writeable as it is first inserted rather
than waiting for a follow-up dax_pfn_mkwrite() =>
finish_mkwrite_fault() call.
Right now we can rely on having a dax_pfn_mkwrite() call because we
can distinguish between these two cases in do_wp_page():
case 1: 4k zero page => writable DAX storage
case 2: read-only DAX storage => writeable DAX storage
This distinction is made by via vm_normal_page(). vm_normal_page()
returns false for the common 4k zero page, though, just as it does
for DAX ptes. Instead of special casing the DAX + 4k zero page case
we will simplify our DAX PTE page fault sequence so that it matches
our DAX PMD sequence, and get rid of the dax_pfn_mkwrite() helper.
We will instead use dax_iomap_fault() to handle write-protection
faults.
This means that insert_pfn() needs to follow the lead of
insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If
'mkwrite' is set insert_pfn() will do the work that was previously
done by wp_page_reuse() as part of the dax_pfn_mkwrite() call path"
Ross Zwisler [Wed, 6 Sep 2017 23:18:35 +0000 (16:18 -0700)]
mm: add vm_insert_mixed_mkwrite()
When servicing mmap() reads from file holes the current DAX code
allocates a page cache page of all zeroes and places the struct page
pointer in the mapping->page_tree radix tree. This has three major
drawbacks:
1) It consumes memory unnecessarily. For every 4k page that is read via
a DAX mmap() over a hole, we allocate a new page cache page. This
means that if you read 1GiB worth of pages, you end up using 1GiB of
zeroed memory.
2) It is slower than using a common zero page because each page fault
has more work to do. Instead of just inserting a common zero page we
have to allocate a page cache page, zero it, and then insert it.
3) The fact that we had to check for both DAX exceptional entries and
for page cache pages in the radix tree made the DAX code more
complex.
This series solves these issues by following the lead of the DAX PMD
code and using a common 4k zero page instead. This reduces memory usage
and decreases latencies for some workloads, and it simplifies the DAX
code, removing over 100 lines in total.
This patch (of 5):
To be able to use the common 4k zero page in DAX we need to have our PTE
fault path look more like our PMD fault path where a PTE entry can be
marked as dirty and writeable as it is first inserted rather than
waiting for a follow-up dax_pfn_mkwrite() => finish_mkwrite_fault()
call.
Right now we can rely on having a dax_pfn_mkwrite() call because we can
distinguish between these two cases in do_wp_page():
case 1: 4k zero page => writable DAX storage
case 2: read-only DAX storage => writeable DAX storage
This distinction is made by via vm_normal_page(). vm_normal_page()
returns false for the common 4k zero page, though, just as it does for
DAX ptes. Instead of special casing the DAX + 4k zero page case we will
simplify our DAX PTE page fault sequence so that it matches our DAX PMD
sequence, and get rid of the dax_pfn_mkwrite() helper. We will instead
use dax_iomap_fault() to handle write-protection faults.
This means that insert_pfn() needs to follow the lead of
insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If 'mkwrite'
is set insert_pfn() will do the work that was previously done by
wp_page_reuse() as part of the dax_pfn_mkwrite() call path.
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.14:
API:
- Defer scompress scratch buffer allocation to first use.
- Add __crypto_xor that takes separte src and dst operands.
- Add ahash multiple registration interface.
- Revamped aead/skcipher algif code to fix async IO properly.
Drivers:
- Add non-SIMD fallback code path on ARM for SVE.
- Add AMD Security Processor framework for ccp.
- Add support for RSA in ccp.
- Add XTS-AES-256 support for CCP version 5.
- Add support for PRNG in sun4i-ss.
- Add support for DPAA2 in caam.
- Add ARTPEC crypto support.
- Add Freescale RNGC hwrng support.
- Add Microchip / Atmel ECC driver.
- Add support for STM32 HASH module"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (116 commits)
crypto: af_alg - get_page upon reassignment to TX SGL
crypto: cavium/nitrox - Fix an error handling path in 'nitrox_probe()'
crypto: inside-secure - fix an error handling path in safexcel_probe()
crypto: rockchip - Don't dequeue the request when device is busy
crypto: cavium - add release_firmware to all return case
crypto: sahara - constify platform_device_id
MAINTAINERS: Add ARTPEC crypto maintainer
crypto: axis - add ARTPEC-6/7 crypto accelerator driver
crypto: hash - add crypto_(un)register_ahashes()
dt-bindings: crypto: add ARTPEC crypto
crypto: algif_aead - fix comment regarding memory layout
crypto: ccp - use dma_mapping_error to check map error
lib/mpi: fix build with clang
crypto: sahara - Remove leftover from previous used spinlock
crypto: sahara - Fix dma unmap direction
crypto: af_alg - consolidation of duplicate code
crypto: caam - Remove unused dentry members
crypto: ccp - select CONFIG_CRYPTO_RSA
crypto: ccp - avoid uninitialized variable warning
crypto: serpent - improve __serpent_setkey with UBSAN
...
1) Support ipv6 checksum offload in sunvnet driver, from Shannon
Nelson.
2) Move to RB-tree instead of custom AVL code in inetpeer, from Eric
Dumazet.
3) Allow generic XDP to work on virtual devices, from John Fastabend.
4) Add bpf device maps and XDP_REDIRECT, which can be used to build
arbitrary switching frameworks using XDP. From John Fastabend.
5) Remove UFO offloads from the tree, gave us little other than bugs.
6) Remove the IPSEC flow cache, from Florian Westphal.
7) Support ipv6 route offload in mlxsw driver.
8) Support VF representors in bnxt_en, from Sathya Perla.
9) Add support for forward error correction modes to ethtool, from
Vidya Sagar Ravipati.
10) Add time filter for packet scheduler action dumping, from Jamal Hadi
Salim.
11) Extend the zerocopy sendmsg() used by virtio and tap to regular
sockets via MSG_ZEROCOPY. From Willem de Bruijn.
12) Significantly rework value tracking in the BPF verifier, from Edward
Cree.
13) Add new jump instructions to eBPF, from Daniel Borkmann.
14) Rework rtnetlink plumbing so that operations can be run without
taking the RTNL semaphore. From Florian Westphal.
15) Support XDP in tap driver, from Jason Wang.
16) Add 32-bit eBPF JIT for ARM, from Shubham Bansal.
17) Add Huawei hinic ethernet driver.
18) Allow to report MD5 keys in TCP inet_diag dumps, from Ivan
Delalande.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1780 commits)
i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq
i40e: avoid NVM acquire deadlock during NVM update
drivers: net: xgene: Remove return statement from void function
drivers: net: xgene: Configure tx/rx delay for ACPI
drivers: net: xgene: Read tx/rx delay for ACPI
rocker: fix kcalloc parameter order
rds: Fix non-atomic operation on shared flag variable
net: sched: don't use GFP_KERNEL under spin lock
vhost_net: correctly check tx avail during rx busy polling
net: mdio-mux: add mdio_mux parameter to mdio_mux_init()
rxrpc: Make service connection lookup always check for retry
net: stmmac: Delete dead code for MDIO registration
gianfar: Fix Tx flow control deactivation
cxgb4: Ignore MPS_TX_INT_CAUSE[Bubble] for T6
cxgb4: Fix pause frame count in t4_get_port_stats
cxgb4: fix memory leak
tun: rename generic_xdp to skb_xdp
tun: reserve extra headroom only when XDP is set
net: dsa: bcm_sf2: Configure IMP port TC2QOS mapping
net: dsa: bcm_sf2: Advertise number of egress queues
...
Merge tag 'wberr-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull writeback error handling updates from Jeff Layton:
"This pile continues the work from last cycle on better tracking
writeback errors. In v4.13 we added some basic errseq_t infrastructure
and converted a few filesystems to use it.
This set continues refining that infrastructure, adds documentation,
and converts most of the other filesystems to use it. The main
exception at this point is the NFS client"
* tag 'wberr-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
ecryptfs: convert to file_write_and_wait in ->fsync
mm: remove optimizations based on i_size in mapping writeback waits
fs: convert a pile of fsync routines to errseq_t based reporting
gfs2: convert to errseq_t based writeback error reporting for fsync
fs: convert sync_file_range to use errseq_t based error-tracking
mm: add file_fdatawait_range and file_write_and_wait
fuse: convert to errseq_t based error tracking for fsync
mm: consolidate dax / non-dax checks for writeback
Documentation: add some docs for errseq_t
errseq: rename __errseq_set to errseq_set
Merge tag 'locks-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull file locking updates from Jeff Layton:
"This pile just has a few file locking fixes from Ben Coddington. There
are a couple of cleanup patches + an attempt to bring sanity to the
l_pid value that is reported back to userland on an F_GETLK request.
After a few gyrations, he came up with a way for filesystems to
communicate to the VFS layer code whether the pid should be translated
according to the namespace or presented as-is to userland"
* tag 'locks-v4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
locks: restore a warn for leaked locks on close
fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks
fs/locks: Use allocation rather than the stack in fcntl_getlk()
Merge tag 'dlm-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm
Pull dlm updates from David Teigland:
"This set includes a bunch of minor code cleanups that have
accumulated, probably from code analyzers people like to run. There is
one nice fix that avoids some socket leaks by switching to use
sock_create_lite()"
* tag 'dlm-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
dlm: use sock_create_lite inside tcp_accept_from_sock
uapi linux/dlm_netlink.h: include linux/dlmconstants.h
dlm: avoid double-free on error path in dlm_device_{register,unregister}
dlm: constify kset_uevent_ops structure
dlm: print log message when cluster name is not set
dlm: Delete an unnecessary variable initialisation in dlm_ls_start()
dlm: Improve a size determination in two functions
dlm: Use kcalloc() in two functions
dlm: Use kmalloc_array() in make_member_array()
dlm: Delete an error message for a failed memory allocation in dlm_recover_waiters_pre()
dlm: Improve a size determination in dlm_recover_waiters_pre()
dlm: Use kcalloc() in dlm_scan_waiters()
dlm: Improve a size determination in table_seq_start()
dlm: Add spaces for better code readability
dlm: Replace six seq_puts() calls by seq_putc()
dlm: Make dismatch error message more clear
dlm: Fix kernel memory disclosure
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"Scalability improvements when allocating inodes, and some
miscellaneous bug fixes and cleanups"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: avoid Y2038 overflow in recently_deleted()
ext4: fix fault handling when mounted with -o dax,ro
ext4: fix quota inconsistency during orphan cleanup for read-only mounts
ext4: fix incorrect quotaoff if the quota feature is enabled
ext4: remove useless test and assignment in strtohash functions
ext4: backward compatibility support for Lustre ea_inode implementation
ext4: remove timebomb in ext4_decode_extra_time()
ext4: use sizeof(*ptr)
ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets
ext4: reduce lock contention in __ext4_new_inode
ext4: cleanup goto next group
ext4: do not unnecessarily allocate buffer in recently_deleted()
Merge tag 'xfs-4.14-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull XFS updates from Darrick Wong:
"Here are the changes for xfs for 4.14. Most of these are cleanups and
fixes for bad behavior, as we're mostly focusing on improving
reliablity this cycle (read: there's potentially a lot of stuff on the
horizon for 4.15 so better to spend a few weeks killing other bugs
now).
Summary:
- Write unmount record for a ro mount to avoid unnecessary log replay
- Clean up orphaned inodes when mounting fs readonly
- Resubmit inode log items when buffer writeback fails to avoid
umount hang
- Fix log recovery corruption problems when log headers wrap around
the end
- Avoid infinite loop searching for free inodes when inode counters
are wrong
- Evict inodes involved with log redo so that we don't leak them
later
- Fix a potential race between reclaim and inode cluster freeing
- Refactor the inode joining code w.r.t. transaction rolling &
deferred ops
- Fix a bug where the log doesn't properly deal with dirty buffers
that are about to become ordered buffers
- Fix the extent swap code to deal with making dirty buffers ordered
properly
- Consolidate page fault handlers
- Refactor the incore extent manipulation functions to use the iext
abstractions instead of directly modifying with extent data
- Disable crashy chattr +/-x until we fix it
- Don't allow us to set S_DAX for v2 inodes
- Various cleanups
- Clarify some documentation
- Fix a problem where fsync and a log commit race to send the disk a
flush command, resulting in a small window where power fail data
loss could occur
- Simplify some rmap operations in the fcollapse code
- Fix some use-after-free problems in async writeback"
* tag 'xfs-4.14-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (44 commits)
xfs: use kmem_free to free return value of kmem_zalloc
xfs: open code end_buffer_async_write in xfs_finish_page_writeback
xfs: don't set v3 xflags for v2 inodes
xfs: fix compiler warnings
fsmap: fix documentation of FMR_OF_LAST
xfs: simplify the rmap code in xfs_bmse_merge
xfs: remove unused flags arg from xfs_file_iomap_begin_delay
xfs: fix incorrect log_flushed on fsync
xfs: disable per-inode DAX flag
xfs: replace xfs_qm_get_rtblks with a direct call to xfs_bmap_count_leaves
xfs: rewrite xfs_bmap_count_leaves using xfs_iext_get_extent
xfs: use xfs_iext_*_extent helpers in xfs_bmap_split_extent_at
xfs: use xfs_iext_*_extent helpers in xfs_bmap_shift_extents
xfs: move some code around inside xfs_bmap_shift_extents
xfs: use xfs_iext_get_extent in xfs_bmap_first_unused
xfs: switch xfs_bmap_local_to_extents to use xfs_iext_insert
xfs: add a xfs_iext_update_extent helper
xfs: consolidate the various page fault handlers
iomap: return VM_FAULT_* codes from iomap_page_mkwrite
xfs: relog dirty buffers during swapext bmbt owner change
...
Merge tag 'gfs2-4.14.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull GFS2 updates from Bob Peterson:
"We've got a whopping 29 GFS2 patches for this merge window, mainly
because we held some back from the previous merge window until we
could get them perfected and well tested. We have a couple patch sets,
including my patch set for protecting glock gl_object and Andreas
Gruenbacher's patch set to fix the long-standing shrink- slab hang,
plus a bunch of assorted bugs and cleanups.
Summary:
- I fixed a bug whereby an IO error would lead to a double-brelse.
- Andreas Gruenbacher made a minor cleanup to call his relatively new
function, gfs2_holder_initialized, rather than doing it manually.
This was just missed by a previous patch set.
- Jan Kara fixed a bug whereby the SGID was being cleared when
inheriting ACLs.
- Andreas found a bug and fixed it in his previous patch, "Get rid of
flush_delayed_work in gfs2_evict_inode". A call to
flush_delayed_work was deleted from *gfs2_inode_lookup and added to
gfs2_create_inode.
- Wang Xibo found and fixed a list_add call in inode_go_lock that
specified the parameters in the wrong order.
- Coly Li submitted a patch to add the REQ_PRIO to some of GFS2's
metadata reads that were accidentally missing them.
- I submitted a 4-patch set to protect the glock gl_object field.
GFS2 was setting and checking gl_object with no locking mechanism,
so the value was occasionally stomped on, which caused file system
corruption.
- I submitted a small cleanup to function gfs2_clear_rgrpd. It was
needlessly adding rgrp glocks to the lru list, then pulling them
back off immediately. The rgrp glocks don't use the lru list
anyway, so doing so was just a waste of time.
- I submitted a patch that checks the GLOF_LRU flag on a glock before
trying to remove it from the lru_list. This avoids a lot of
unnecessary spin_lock contention.
- I submitted a patch to delete GFS2's debugfs files only after we
evict all the glocks. Before this patch, GFS2 would delete the
debugfs files, and if unmount hung waiting for a glock, there was
no way to debug the problem. Now, if a hang occurs during umount,
we can examine the debugfs files to figure out why it's hung.
- Andreas Gruenbacher submitted a patch to fix some trivial typos.
- Andreas also submitted a five-part patch set to fix the
longstanding hang involving the slab shrinker: dlm requires memory,
calls the inode shrinker, which calls gfs2's evict, which calls
back into DLM before it can evict an inode.
- Abhi Das submitted a patch to forcibly flush the active items list
to relieve memory pressure. This fixes a long-standing bug whereby
GFS2 was getting hung permanently in balance_dirty_pages.
- Thomas Tai submitted a patch to fix a slab corruption problem due
to a residual pointer left in the lock_dlm lockstruct.
- I submitted a patch to withdraw the file system if IO errors are
encountered while writing to the journals or statfs system file
which were previously not being sent back up. Before, some IO
errors were sometimes not be detected for several hours, and at
recovery time, the journal errors made journal replay impossible.
- Andreas has a patch to fix an annoying format-truncation compiler
warning so GFS2 compiles cleanly.
- I have a patch that fixes a handful of sparse compiler warnings.
- Andreas fixed up an useless gl_object warning caused by an earlier
patch.
- Arvind Yadav added a patch to properly constify our rhashtable
params declare.
- I added a patch to fix a regression caused by the non-recursive
delete and truncate patch that caused file system blocks to not be
properly freed.
- Ernesto A. Fernández added a patch to fix a place where GFS2 would
send back the wrong return code setting extended attributes.
- Ernesto also added a patch to fix a case in which GFS2 was
improperly setting an inode's i_mode, potentially granting access
to the wrong users"
* tag 'gfs2-4.14.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (29 commits)
gfs2: preserve i_mode if __gfs2_set_acl() fails
gfs2: don't return ENODATA in __gfs2_xattr_set unless replacing
GFS2: Fix non-recursive truncate bug
gfs2: constify rhashtable_params
GFS2: Fix gl_object warnings
GFS2: Fix up some sparse warnings
gfs2: Silence gcc format-truncation warning
GFS2: Withdraw for IO errors writing to the journal or statfs
gfs2: fix slab corruption during mounting and umounting gfs file system
gfs2: forcibly flush ail to relieve memory pressure
gfs2: Clean up waiting on glocks
gfs2: Defer deleting inodes under memory pressure
gfs2: gfs2_evict_inode: Put glocks asynchronously
gfs2: Get rid of gfs2_set_nlink
gfs2: gfs2_glock_get: Wait on freeing glocks
gfs2: Fix trivial typos
GFS2: Delete debugfs files only after we evict the glocks
GFS2: Don't waste time locking lru_lock for non-lru glocks
GFS2: Don't bother trying to add rgrps to the lru list
GFS2: Clear gl_object when deleting an inode in gfs2_delete_inode
...
Chris Wilson [Wed, 6 Sep 2017 11:14:05 +0000 (12:14 +0100)]
drm/i915: Re-enable GTT following a device reset
Ville Syrjälä spotted that PGETBL_CTL was losing its enable bit upon a
reset. That was causing the display to show garbage on his 945gm. On my
i915gm the effect was far more severe; re-enabling the display following
the reset without PGETBL_CTL being enabled lead to an immediate hard
hang.
We do have a routine to re-enable PGETBL_CTL which is applicable to
gen2-4, although on gen4 it is documented that a graphics reset doesn't
alter the register (no such wording is given for gen3) and should be safe
to call to punch back in the enable bit. However, that leaves the question
of whether we need to completely re-initialise the register and the
rest of the GSM. For g33/pnv/gen4+, where we do have a configurable
page table, its contents do seem to be kept, and so we should be able to
recover without having to reinitialise the GTT from scratch (as prior to
g33, that register is configured by the BIOS and we leave alone except
for the enable bit).
This appears to have been broken by commit 5fbd0418eef2 ("drm/i915:
Re-enable GGTT earlier during resume on pre-gen6 platforms"), which
moved the intel_enable_gtt() from i915_gem_init_hw() (also used by
reset) to add it earlier during hw init and resume, missing the reset
path.
v2: Find the culprit, rearrange ggtt_enable to be before gem_init_hw to
match init/resume
Ville Syrjälä [Fri, 1 Sep 2017 16:54:34 +0000 (19:54 +0300)]
drm/i915: Annotate user relocs with __user
Add the missing __user to the urelocs cast to fix the following sparse
warning:
i915_gem_execbuffer.c:1541:47: warning: cast removes address space of expression
i915_gem_execbuffer.c:1541:62: warning: incorrect type in argument 2 (different address spaces)
i915_gem_execbuffer.c:1541:62: expected void const [noderef] <asn:1>*from
i915_gem_execbuffer.c:1541:62: got char *
David S. Miller [Wed, 6 Sep 2017 03:03:40 +0000 (20:03 -0700)]
Merge branch '40GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net-queue
Jeff Kirsher says:
====================
Intel Wired LAN Driver Updates 2017-09-05
This series contains fixes for i40e only.
These two patches fix an issue where our nvmupdate tool does not work on RHEL 7.4
and newer kernels, in fact, the use of the nvmupdate tool on newer kernels can
cause the cards to be non-functional unless these patches are applied.
Anjali reworks the locking around accessing the NVM so that NVM acquire timeouts
do not occur which was causing the failed firmware updates.
Jake correctly updates the wb_desc when reading the NVM through the AdminQ.
====================
Jacob Keller [Fri, 1 Sep 2017 20:43:08 +0000 (13:43 -0700)]
i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq
When introducing the functions to read the NVM through the AdminQ, we
did not correctly mark the wb_desc.
Fixes: 7073f46e443e ("i40e: Add AQ commands for NVM Update for X722", 2015-06-05) Signed-off-by: Jacob Keller <[email protected]> Tested-by: Andrew Bowers <[email protected]> Signed-off-by: Jeff Kirsher <[email protected]>
i40e: avoid NVM acquire deadlock during NVM update
X722 devices use the AdminQ to access the NVM, and this requires taking
the AdminQ lock. Because of this, we lock the AdminQ during
i40e_read_nvm(), which is also called in places where the lock is
already held, such as the firmware update path which wants to lock once
and then unlock when finished after performing several tasks.
Although this should have only affected X722 devices, commit 96a39aed25e6 ("i40e: Acquire NVM lock before reads on all devices",
2016-12-02) added locking for all NVM reads, regardless of device
family.
This resulted in us accidentally causing NVM acquire timeouts on all
devices, causing failed firmware updates which left the eeprom in
a corrupt state.
Create unsafe non-locked variants of i40e_read_nvm_word and
i40e_read_nvm_buffer, __i40e_read_nvm_word and __i40e_read_nvm_buffer
respectively. These variants will not take the NVM lock and are expected
to only be called in places where the NVM lock is already held if
needed.
Since the only caller of i40e_read_nvm_buffer() was in such a path,
remove it entirely in favor of the unsafe version. If necessary we can
always add it back in the future.
Additionally, we now need to hold the NVM lock in i40e_validate_checksum
because the call to i40e_calc_nvm_checksum now assumes that the NVM lock
is held. We can further move the call to read I40E_SR_SW_CHECKSUM_WORD
up a bit so that we do not need to acquire the NVM lock twice.
This should resolve firmware updates and also fix potential raise that
could have caused the driver to report an invalid NVM checksum upon
driver load.
The function calls to kcalloc use wrong parameter order and incorrect flags
values. GFP_KERNEL is used instead of flags now and the order is corrected.
The change was done using the following coccinelle script:
rds: Fix non-atomic operation on shared flag variable
The bits in m_flags in struct rds_message are used for a plurality of
reasons, and from different contexts. To avoid any missing updates to
m_flags, use the atomic set_bit() instead of the non-atomic equivalent.
Jason Wang [Tue, 5 Sep 2017 01:22:05 +0000 (09:22 +0800)]
vhost_net: correctly check tx avail during rx busy polling
We check tx avail through vhost_enable_notify() in the past which is
wrong since it only checks whether or not guest has filled more
available buffer since last avail idx synchronization which was just
done by vhost_vq_avail_empty() before. What we really want is checking
pending buffers in the avail ring. Fix this by calling
vhost_vq_avail_empty() instead.
This issue could be noticed by doing netperf TCP_RR benchmark as
client from guest (but not host). With this fix, TCP_RR from guest to
localhost restores from 1375.91 trans per sec to 55235.28 trans per
sec on my laptop (Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz).
Fixes: 030881372460 ("vhost_net: basic polling support") Signed-off-by: Jason Wang <[email protected]> Signed-off-by: David S. Miller <[email protected]>
David Howells [Mon, 4 Sep 2017 14:28:28 +0000 (15:28 +0100)]
rxrpc: Make service connection lookup always check for retry
When an RxRPC service packet comes in, the target connection is looked up
by an rb-tree search under RCU and a read-locked seqlock; the seqlock retry
check is, however, currently skipped if we got a match, but probably
shouldn't be in case the connection we found gets replaced whilst we're
doing a search.
Make the lookup procedure always go through need_seqretry(), even if the
lookup was successful. This makes sure we always pick up on a write-lock
event.
On the other hand, since we don't take a ref on the object, but rely on RCU
to prevent its destruction after dropping the seqlock, I'm not sure this is
necessary.
net: stmmac: Delete dead code for MDIO registration
This code is no longer used, the logging function was changed by commit fbca164776e4 ("net: stmmac: Use the right logging function in stmmac_mdio_register").
It was previously showing information about the type of the IRQ, if it's
polled, ignored or a normal interrupt. As we don't want information loss,
I have moved this code to phy_attached_print().
Fixes: fbca164776e4 ("net: stmmac: Use the right logging function in stmmac_mdio_register") Signed-off-by: Romain Perier <[email protected]> Signed-off-by: David S. Miller <[email protected]>
The wrong register is checked for the Tx flow control bit,
it should have been maccfg1 not maccfg2.
This went unnoticed for so long probably because the impact is
hardly visible, not to mention the tangled code from adjust_link().
First, link flow control (i.e. handling of Rx/Tx link level pause frames)
is disabled by default (needs to be enabled via 'ethtool -A').
Secondly, maccfg2 always returns 0 for tx_flow_oldval (except for a few
old boards), which results in Tx flow control remaining always on
once activated.
Fixes: 45b679c9a3ccd9e34f28e6ec677b812a860eb8eb ("gianfar: Implement PAUSE frame generation support") Signed-off-by: Claudiu Manoil <[email protected]> Signed-off-by: David S. Miller <[email protected]>
projects / linux.git / log