Commit 23baf831a3 ("mm, treewide: redefine MAX_ORDER sanely")
changed the meaning of MAX_ORDER from exclusive to inclusive. So, we
can allocate compound pages with up to 1 << MAX_ORDER pages.
Reflect this change in dm-crypt and start trying to allocate compound
pages with MAX_ORDER.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
The commit 5721d4e5a9 enhanced dm-verity, so that it can verify blocks
from tasklets rather than from workqueues. This reportedly improves
performance significantly.
However, dm-verity was using the flag CRYPTO_TFM_REQ_MAY_SLEEP from
tasklets which resulted in warnings about sleeping function being called
from non-sleeping context.
BUG: sleeping function called from invalid context at crypto/internal.h:206
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 14, name: ksoftirqd/0
preempt_count: 100, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 PID: 14 Comm: ksoftirqd/0 Tainted: G W 6.7.0-rc1 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x32/0x50
__might_resched+0x110/0x160
crypto_hash_walk_done+0x54/0xb0
shash_ahash_update+0x51/0x60
verity_hash_update.isra.0+0x4a/0x130 [dm_verity]
verity_verify_io+0x165/0x550 [dm_verity]
? free_unref_page+0xdf/0x170
? psi_group_change+0x113/0x390
verity_tasklet+0xd/0x70 [dm_verity]
tasklet_action_common.isra.0+0xb3/0xc0
__do_softirq+0xaf/0x1ec
? smpboot_thread_fn+0x1d/0x200
? sort_range+0x20/0x20
run_ksoftirqd+0x15/0x30
smpboot_thread_fn+0xed/0x200
kthread+0xdc/0x110
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x28/0x40
? kthread_complete_and_exit+0x20/0x20
ret_from_fork_asm+0x11/0x20
</TASK>
This commit fixes dm-verity so that it doesn't use the flags
CRYPTO_TFM_REQ_MAY_SLEEP and CRYPTO_TFM_REQ_MAY_BACKLOG from tasklets. The
crypto API would do GFP_ATOMIC allocation instead, it could return -ENOMEM
and we catch -ENOMEM in verity_tasklet and requeue the request to the
workqueue.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v6.0+
Fixes: 5721d4e5a9 ("dm verity: Add optional "try_verify_in_tasklet" feature")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
dm-bufio has a no-sleep mode. When activated (with the
DM_BUFIO_CLIENT_NO_SLEEP flag), the bufio client is read-only and we
could call dm_bufio_get from tasklets. This is used by dm-verity.
Unfortunately, commit 450e8dee51 ("dm bufio: improve concurrent IO
performance") broke this and the kernel would warn that cache_get()
was calling down_read() from no-sleeping context. The bug can be
reproduced by using "veritysetup open" with the "--use-tasklets"
flag.
This commit fixes dm-bufio, so that the tasklet mode works again, by
expanding use of the 'no_sleep_enabled' static_key to conditionally
use either a rw_semaphore or rwlock_t (which are colocated in the
buffer_tree structure using a union).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v6.4
Fixes: 450e8dee51 ("dm bufio: improve concurrent IO performance")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
This is small refactoring of dm-delay - we avoid duplicate logic in
flush_delayed_bios and flush_delayed_bios_fast and join these two
functions into one.
We also add cond_resched() to flush_delayed_bios because the list may have
unbounded number of entries.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
This commit fixes the following bugs introduced by commit 70bbeb29fa
("dm delay: for short delays, use kthread instead of timers and wq"):
* the function flush_worker_fn has no exit path - on unload, this
function will just loop and consume 100% CPU without any progress
* the wake-up mechanism in flush_worker_fn is racy - a wake up will be
missed if the process adds entries to the delayed_bios list just
before set_current_state(TASK_INTERRUPTIBLE)
* flush_delayed_bios_fast submits a bio while holding a global mutex;
this may deadlock if we have multiple stacked dm-delay devices and
the underlying device attempts to acquire the mutex too
* if the target constructor fails, it will call delay_dtr. delay_dtr
would attempt to free dc->timer_lock without it being initialized by
the constructor.
* if the target constructor's kthread allocation fails, delay_dtr
would crash trying to dereference dc->worker because it is non-NULL
due to ERR_PTR.
Fixes: 70bbeb29fa ("dm delay: for short delays, use kthread instead of timers and wq")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
In delay_presuspend, we set the atomic variable may_delay and then stop
the timer and flush pending bios. The intention here is to prevent the
delay target from re-arming the timer again.
However, this test is racy. Suppose that one thread goes to delay_bio,
sees that dc->may_delay is one and proceeds; now, another thread executes
delay_presuspend, it sets dc->may_delay to zero, deletes the timer and
flushes pending bios. Then, the first thread continues and adds the bio to
delayed->list despite the fact that dc->may_delay is false.
Fix this bug by changing may_delay's type from atomic_t to bool and
only access it while holding the delayed_bios_lock mutex. Note that we
don't have to grab the mutex in delay_resume because there are no bios
in flight at this point.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Pull MM updates from Andrew Morton:
"Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Kemeng Shi has contributed some compation maintenance work in the
series 'Fixes and cleanups to compaction'
- Joel Fernandes has a patchset ('Optimize mremap during mutual
alignment within PMD') which fixes an obscure issue with mremap()'s
pagetable handling during a subsequent exec(), based upon an
implementation which Linus suggested
- More DAMON/DAMOS maintenance and feature work from SeongJae Park i
the following patch series:
mm/damon: misc fixups for documents, comments and its tracepoint
mm/damon: add a tracepoint for damos apply target regions
mm/damon: provide pseudo-moving sum based access rate
mm/damon: implement DAMOS apply intervals
mm/damon/core-test: Fix memory leaks in core-test
mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
- In the series 'Do not try to access unaccepted memory' Adrian
Hunter provides some fixups for the recently-added 'unaccepted
memory' feature. To increase the feature's checking coverage. 'Plug
a few gaps where RAM is exposed without checking if it is
unaccepted memory'
- In the series 'cleanups for lockless slab shrink' Qi Zheng has done
some maintenance work which is preparation for the lockless slab
shrinking code
- Qi Zheng has redone the earlier (and reverted) attempt to make slab
shrinking lockless in the series 'use refcount+RCU method to
implement lockless slab shrink'
- David Hildenbrand contributes some maintenance work for the rmap
code in the series 'Anon rmap cleanups'
- Kefeng Wang does more folio conversions and some maintenance work
in the migration code. Series 'mm: migrate: more folio conversion
and unification'
- Matthew Wilcox has fixed an issue in the buffer_head code which was
causing long stalls under some heavy memory/IO loads. Some cleanups
were added on the way. Series 'Add and use bdev_getblk()'
- In the series 'Use nth_page() in place of direct struct page
manipulation' Zi Yan has fixed a potential issue with the direct
manipulation of hugetlb page frames
- In the series 'mm: hugetlb: Skip initialization of gigantic tail
struct pages if freed by HVO' has improved our handling of gigantic
pages in the hugetlb vmmemmep optimizaton code. This provides
significant boot time improvements when significant amounts of
gigantic pages are in use
- Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
rationalization and folio conversions in the hugetlb code
- Yin Fengwei has improved mlock()'s handling of large folios in the
series 'support large folio for mlock'
- In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
added statistics for memcg v1 users which are available (and
useful) under memcg v2
- Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
prctl so that userspace may direct the kernel to not automatically
propagate the denial to child processes. The series is named 'MDWE
without inheritance'
- Kefeng Wang has provided the series 'mm: convert numa balancing
functions to use a folio' which does what it says
- In the series 'mm/ksm: add fork-exec support for prctl' Stefan
Roesch makes is possible for a process to propagate KSM treatment
across exec()
- Huang Ying has enhanced memory tiering's calculation of memory
distances. This is used to permit the dax/kmem driver to use 'high
bandwidth memory' in addition to Optane Data Center Persistent
Memory Modules (DCPMM). The series is named 'memory tiering:
calculate abstract distance based on ACPI HMAT'
- In the series 'Smart scanning mode for KSM' Stefan Roesch has
optimized KSM by teaching it to retain and use some historical
information from previous scans
- Yosry Ahmed has fixed some inconsistencies in memcg statistics in
the series 'mm: memcg: fix tracking of pending stats updates
values'
- In the series 'Implement IOCTL to get and optionally clear info
about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
which permits us to atomically read-then-clear page softdirty
state. This is mainly used by CRIU
- Hugh Dickins contributed the series 'shmem,tmpfs: general
maintenance', a bunch of relatively minor maintenance tweaks to
this code
- Matthew Wilcox has increased the use of the VMA lock over
file-backed page faults in the series 'Handle more faults under the
VMA lock'. Some rationalizations of the fault path became possible
as a result
- In the series 'mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()' David Hildenbrand has implemented some
cleanups and folio conversions
- In the series 'various improvements to the GUP interface' Lorenzo
Stoakes has simplified and improved the GUP interface with an eye
to providing groundwork for future improvements
- Andrey Konovalov has sent along the series 'kasan: assorted fixes
and improvements' which does those things
- Some page allocator maintenance work from Kemeng Shi in the series
'Two minor cleanups to break_down_buddy_pages'
- In thes series 'New selftest for mm' Breno Leitao has developed
another MM self test which tickles a race we had between madvise()
and page faults
- In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
and an optimization to the core pagecache code
- Nhat Pham has added memcg accounting for hugetlb memory in the
series 'hugetlb memcg accounting'
- Cleanups and rationalizations to the pagemap code from Lorenzo
Stoakes, in the series 'Abstract vma_merge() and split_vma()'
- Audra Mitchell has fixed issues in the procfs page_owner code's new
timestamping feature which was causing some misbehaviours. In the
series 'Fix page_owner's use of free timestamps'
- Lorenzo Stoakes has fixed the handling of new mappings of sealed
files in the series 'permit write-sealed memfd read-only shared
mappings'
- Mike Kravetz has optimized the hugetlb vmemmap optimization in the
series 'Batch hugetlb vmemmap modification operations'
- Some buffer_head folio conversions and cleanups from Matthew Wilcox
in the series 'Finish the create_empty_buffers() transition'
- As a page allocator performance optimization Huang Ying has added
automatic tuning to the allocator's per-cpu-pages feature, in the
series 'mm: PCP high auto-tuning'
- Roman Gushchin has contributed the patchset 'mm: improve
performance of accounted kernel memory allocations' which improves
their performance by ~30% as measured by a micro-benchmark
- folio conversions from Kefeng Wang in the series 'mm: convert page
cpupid functions to folios'
- Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
kmemleak'
- Qi Zheng has improved our handling of memoryless nodes by keeping
them off the allocation fallback list. This is done in the series
'handle memoryless nodes more appropriately'
- khugepaged conversions from Vishal Moola in the series 'Some
khugepaged folio conversions'"
[ bcachefs conflicts with the dynamically allocated shrinkers have been
resolved as per Stephen Rothwell in
https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/
with help from Qi Zheng.
The clone3 test filtering conflict was half-arsed by yours truly ]
* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
mm/damon/sysfs: update monitoring target regions for online input commit
mm/damon/sysfs: remove requested targets when online-commit inputs
selftests: add a sanity check for zswap
Documentation: maple_tree: fix word spelling error
mm/vmalloc: fix the unchecked dereference warning in vread_iter()
zswap: export compression failure stats
Documentation: ubsan: drop "the" from article title
mempolicy: migration attempt to match interleave nodes
mempolicy: mmap_lock is not needed while migrating folios
mempolicy: alloc_pages_mpol() for NUMA policy without vma
mm: add page_rmappable_folio() wrapper
mempolicy: remove confusing MPOL_MF_LAZY dead code
mempolicy: mpol_shared_policy_init() without pseudo-vma
mempolicy trivia: use pgoff_t in shared mempolicy tree
mempolicy trivia: slightly more consistent naming
mempolicy trivia: delete those ancient pr_debug()s
mempolicy: fix migrate_pages(2) syscall return nr_failed
kernfs: drop shared NUMA mempolicy hooks
hugetlbfs: drop shared NUMA mempolicy pretence
mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
...
Pull sysctl updates from Luis Chamberlain:
"To help make the move of sysctls out of kernel/sysctl.c not incur a
size penalty sysctl has been changed to allow us to not require the
sentinel, the final empty element on the sysctl array. Joel Granados
has been doing all this work. On the v6.6 kernel we got the major
infrastructure changes required to support this. For v6.7-rc1 we have
all arch/ and drivers/ modified to remove the sentinel. Both arch and
driver changes have been on linux-next for a bit less than a month. It
is worth re-iterating the value:
- this helps reduce the overall build time size of the kernel and run
time memory consumed by the kernel by about ~64 bytes per array
- the extra 64-byte penalty is no longer inncurred now when we move
sysctls out from kernel/sysctl.c to their own files
For v6.8-rc1 expect removal of all the sentinels and also then the
unneeded check for procname == NULL.
The last two patches are fixes recently merged by Krister Johansen
which allow us again to use softlockup_panic early on boot. This used
to work but the alias work broke it. This is useful for folks who want
to detect softlockups super early rather than wait and spend money on
cloud solutions with nothing but an eventual hung kernel. Although
this hadn't gone through linux-next it's also a stable fix, so we
might as well roll through the fixes now"
* tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (23 commits)
watchdog: move softlockup_panic back to early_param
proc: sysctl: prevent aliased sysctls from getting passed to init
intel drm: Remove now superfluous sentinel element from ctl_table array
Drivers: hv: Remove now superfluous sentinel element from ctl_table array
raid: Remove now superfluous sentinel element from ctl_table array
fw loader: Remove the now superfluous sentinel element from ctl_table array
sgi-xp: Remove the now superfluous sentinel element from ctl_table array
vrf: Remove the now superfluous sentinel element from ctl_table array
char-misc: Remove the now superfluous sentinel element from ctl_table array
infiniband: Remove the now superfluous sentinel element from ctl_table array
macintosh: Remove the now superfluous sentinel element from ctl_table array
parport: Remove the now superfluous sentinel element from ctl_table array
scsi: Remove now superfluous sentinel element from ctl_table array
tty: Remove now superfluous sentinel element from ctl_table array
xen: Remove now superfluous sentinel element from ctl_table array
hpet: Remove now superfluous sentinel element from ctl_table array
c-sky: Remove now superfluous sentinel element from ctl_talbe array
powerpc: Remove now superfluous sentinel element from ctl_table arrays
riscv: Remove now superfluous sentinel element from ctl_table array
x86/vdso: Remove now superfluous sentinel element from ctl_table array
...
Pull device mapper updates from Mike Snitzer:
- Update DM core to directly call the map function for both the linear
and stripe targets; which are provided by DM core
- Various updates to use new safer string functions
- Update DM core to respect REQ_NOWAIT flag in normal bios so that
memory allocations are always attempted with GFP_NOWAIT
- Add Mikulas Patocka to MAINTAINERS as a DM maintainer!
- Improve DM delay target's handling of short delays (< 50ms) by using
a kthread to check expiration of IOs rather than timers and a wq
- Update the DM error target so that it works with zoned storage. This
helps xfstests to provide proper IO error handling coverage when
testing a filesystem with native zoned storage support
- Update both DM crypt and integrity targets to improve performance by
using crypto_shash_digest() rather than init+update+final sequence
- Fix DM crypt target by backfilling missing memory allocation
accounting for compound pages
* tag 'for-6.7/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm crypt: account large pages in cc->n_allocated_pages
dm integrity: use crypto_shash_digest() in sb_mac()
dm crypt: use crypto_shash_digest() in crypt_iv_tcw_whitening()
dm error: Add support for zoned block devices
dm delay: for short delays, use kthread instead of timers and wq
MAINTAINERS: add Mikulas Patocka as a DM maintainer
dm: respect REQ_NOWAIT flag in normal bios issued to DM
dm: enhance alloc_multiple_bios() to be more versatile
dm: make __send_duplicate_bios return unsigned int
dm log userspace: replace deprecated strncpy with strscpy
dm ioctl: replace deprecated strncpy with strscpy_pad
dm crypt: replace open-coded kmemdup_nul
dm cache metadata: replace deprecated strncpy with strscpy
dm: shortcut the calls to linear_map and stripe_map
Pull block updates from Jens Axboe:
- Improvements to the queue_rqs() support, and adding null_blk support
for that as well (Chengming)
- Series improving badblocks support (Coly)
- Key store support for sed-opal (Greg)
- IBM partition string handling improvements (Jan)
- Make number of ublk devices supported configurable (Mike)
- Cancelation improvements for ublk (Ming)
- MD pull requests via Song:
- Handle timeout in md-cluster, by Denis Plotnikov
- Cleanup pers->prepare_suspend, by Yu Kuai
- Rewrite mddev_suspend(), by Yu Kuai
- Simplify md_seq_ops, by Yu Kuai
- Reduce unnecessary locking array_state_store(), by Mariusz
Tkaczyk
- Make rdev add/remove independent from daemon thread, by Yu Kuai
- Refactor code around quiesce() and mddev_suspend(), by Yu Kuai
- NVMe pull request via Keith:
- nvme-auth updates (Mark)
- nvme-tcp tls (Hannes)
- nvme-fc annotaions (Kees)
- Misc cleanups and improvements (Jiapeng, Joel)
* tag 'for-6.7/block-2023-10-30' of git://git.kernel.dk/linux: (95 commits)
block: ublk_drv: Remove unused function
md: cleanup pers->prepare_suspend()
nvme-auth: allow mixing of secret and hash lengths
nvme-auth: use transformed key size to create resp
nvme-auth: alloc nvme_dhchap_key as single buffer
nvmet-tcp: use 'spin_lock_bh' for state_lock()
powerpc/pseries: PLPKS SED Opal keystore support
block: sed-opal: keystore access for SED Opal keys
block:sed-opal: SED Opal keystore
ublk: simplify aborting request
ublk: replace monitor with cancelable uring_cmd
ublk: quiesce request queue when aborting queue
ublk: rename mm_lock as lock
ublk: move ublk_cancel_dev() out of ub->mutex
ublk: make sure io cmd handled in submitter task context
ublk: don't get ublk device reference in ublk_abort_queue()
ublk: Make ublks_max configurable
ublk: Limit dev_id/ub_number values
md-cluster: check for timeout while a new disk adding
nvme: rework NVME_AUTH Kconfig selection
...
The commit 5054e778fc ("dm crypt: allocate compound pages if
possible") changed dm-crypt to use compound pages to improve
performance. Unfortunately, there was an oversight: the allocation of
compound pages was not accounted at all. Normal pages are accounted in
a percpu counter cc->n_allocated_pages and dm-crypt is limited to
allocate at most 2% of memory. Because compound pages were not
accounted at all, dm-crypt could allocate memory over the 2% limit.
Fix this by adding the accounting of compound pages, so that memory
consumption of dm-crypt is properly limited.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 5054e778fc ("dm crypt: allocate compound pages if possible")
Cc: stable@vger.kernel.org # v6.5+
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Simplify sb_mac() by using crypto_shash_digest() instead of an
init+update+final sequence. This should also improve performance.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Simplify crypt_iv_tcw_whitening() by using crypto_shash_digest() instead
of an init+update+final sequence. This should also improve performance.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
dm-error is used in several test cases in the xfstests test suite to
check the handling of IO errors in file systems. However, with several
file systems getting native support for zoned block devices (e.g.
btrfs and f2fs), dm-error's lack of zoned block device support creates
problems as the file system attempts executing zone commands (e.g. a
zone append operation) against a dm-error non-zoned block device,
which causes various issues in the block layer (e.g. WARN_ON
triggers).
This commit adds supports for zoned block devices to dm-error, allowing
a DM device table containing an error target to be exposed as a zoned
block device (if all targets have a compatible zoned model support and
mapping). This is done as follows:
1) Allow passing 2 arguments to an error target, similar to dm-linear:
a backing device and a start sector. These arguments are optional and
dm-error retains its characteristics if the arguments are not
specified.
2) Implement the iterate_devices method so that dm-core can normally
check the zone support and restrictions (e.g. zone alignment of the
targets). When the backing device arguments are not specified, the
iterate_devices method never calls the fn() argument.
When no backing device is specified, as before, we assume that the DM
device is not zoned. When the backing device arguments are specified,
the zoned model of the DM device will depend on the backing device
type:
- If the backing device is zoned and its model and mapping is
compatible with other targets of the device, the resulting device
will be zoned, with the dm-error mapped portion always returning
errors (similar to the default non-zoned case).
- If the backing device is not zoned, then the DM device will not be
either.
This zone support for dm-error requires the definition of a functional
report_zones operation so that dm_revalidate_zones() can operate
correctly and resources for emulating zone append operations
initialized. This is necessary for cases where dm-error is used to
partially map a device and have an overall correct handling of zone
append. This means that dm-error does not fail report zones operations.
Two changes that are not obvious are included to avoid issues:
1) dm_table_supports_zoned_model() is changed to directly check if
the backing device of a wildcard target (= dm-error target) is
zoned. Otherwise, we wouldn't be able to catch the invalid setup of
dm-error without a backing device (non zoned case) being combined
with zoned targets.
2) dm_table_supports_dax() is modified to return false if the wildcard
target is found. Otherwise, when dm-error is set without a backing
device, we end up with a NULL pointer dereference in
set_dax_synchronous (dax_dev is NULL). This is consistent with the
current behavior because dm_table_supports_dax() always returned
false for targets that do not define the iterate_devices method.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
DM delay's current design of using timers and wq to realize the delays
is insufficient for delays below ~50ms.
This commit enhances the design to use a kthread to flush the expired
delays, trading some CPU time (in some cases) for better delay
accuracy and delays closer to what the user requested for smaller
delays. The new design is chosen as long as all the delays are below
50ms.
Since bios can't be completed in interrupt context using a kthread
is probably the most reasonable way to approach this.
Testing with
echo "0 2097152 zero" | dmsetup create dm-zeros
for i in $(seq 0 20);
do
echo "0 2097152 delay /dev/mapper/dm-zeros 0 $i" | dmsetup create dm-delay-${i}ms;
done
Some performance numbers for comparison, on beaglebone black (single
core) CONFIG_HZ_1000=y:
fio --name=1msread --rw=randread --bs=4k --runtime=60 --time_based \
--filename=/dev/mapper/dm-delay-1ms
Theoretical maximum: 1000 IOPS
Previous: 250 IOPS
Kthread: 500 IOPS
fio --name=10msread --rw=randread --bs=4k --runtime=60 --time_based \
--filename=/dev/mapper/dm-delay-10ms
Theoretical maximum: 100 IOPS
Previous: 45 IOPS
Kthread: 50 IOPS
fio --name=1mswrite --rw=randwrite --direct=1 --bs=4k --runtime=60 \
--time_based --filename=/dev/mapper/dm-delay-1ms
Theoretical maximum: 1000 IOPS
Previous: 498 IOPS
Kthread: 1000 IOPS
fio --name=10mswrite --rw=randwrite --direct=1 --bs=4k --runtime=60 \
--time_based --filename=/dev/mapper/dm-delay-10ms
Theoretical maximum: 100 IOPS
Previous: 90 IOPS
Kthread: 100 IOPS
(This one is just to prove the new design isn't impacting throughput,
not really about delays):
fio --name=10mswriteasync --rw=randwrite --direct=1 --bs=4k \
--runtime=60 --time_based --filename=/dev/mapper/dm-delay-10ms \
--numjobs=32 --iodepth=64 --ioengine=libaio --group_reporting
Previous: 13.3k IOPS
Kthread: 13.3k IOPS
Signed-off-by: Christian Loehle <christian.loehle@arm.com>
[Harshit: kthread_create error handling fix in delay_ctr]
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Pull hardening updates from Kees Cook:
"One of the more voluminous set of changes is for adding the new
__counted_by annotation[1] to gain run-time bounds checking of
dynamically sized arrays with UBSan.
- Add LKDTM test for stuck CPUs (Mark Rutland)
- Improve LKDTM selftest behavior under UBSan (Ricardo Cañuelo)
- Refactor more 1-element arrays into flexible arrays (Gustavo A. R.
Silva)
- Analyze and replace strlcpy and strncpy uses (Justin Stitt, Azeem
Shaikh)
- Convert group_info.usage to refcount_t (Elena Reshetova)
- Add __counted_by annotations (Kees Cook, Gustavo A. R. Silva)
- Add Kconfig fragment for basic hardening options (Kees Cook, Lukas
Bulwahn)
- Fix randstruct GCC plugin performance mode to stay in groups (Kees
Cook)
- Fix strtomem() compile-time check for small sources (Kees Cook)"
* tag 'hardening-v6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (56 commits)
hwmon: (acpi_power_meter) replace open-coded kmemdup_nul
reset: Annotate struct reset_control_array with __counted_by
kexec: Annotate struct crash_mem with __counted_by
virtio_console: Annotate struct port_buffer with __counted_by
ima: Add __counted_by for struct modsig and use struct_size()
MAINTAINERS: Include stackleak paths in hardening entry
string: Adjust strtomem() logic to allow for smaller sources
hardening: x86: drop reference to removed config AMD_IOMMU_V2
randstruct: Fix gcc-plugin performance mode to stay in group
mailbox: zynqmp: Annotate struct zynqmp_ipi_pdata with __counted_by
drivers: thermal: tsens: Annotate struct tsens_priv with __counted_by
irqchip/imx-intmux: Annotate struct intmux_data with __counted_by
KVM: Annotate struct kvm_irq_routing_table with __counted_by
virt: acrn: Annotate struct vm_memory_region_batch with __counted_by
hwmon: Annotate struct gsc_hwmon_platform_data with __counted_by
sparc: Annotate struct cpuinfo_tree with __counted_by
isdn: kcapi: replace deprecated strncpy with strscpy_pad
isdn: replace deprecated strncpy with strscpy
NFS/flexfiles: Annotate struct nfs4_ff_layout_segment with __counted_by
nfs41: Annotate struct nfs4_file_layout_dsaddr with __counted_by
...
Pull initial bcachefs updates from Kent Overstreet:
"Here's the bcachefs filesystem pull request.
One new patch since last week: the exportfs constants ended up
conflicting with other filesystems that are also getting added to the
global enum, so switched to new constants picked by Amir.
The only new non fs/bcachefs/ patch is the objtool patch that adds
bcachefs functions to the list of noreturns. The patch that exports
osq_lock() has been dropped for now, per Ingo"
* tag 'bcachefs-2023-10-30' of https://evilpiepirate.org/git/bcachefs: (2781 commits)
exportfs: Change bcachefs fid_type enum to avoid conflicts
bcachefs: Refactor memcpy into direct assignment
bcachefs: Fix drop_alloc_keys()
bcachefs: snapshot_create_lock
bcachefs: Fix snapshot skiplists during snapshot deletion
bcachefs: bch2_sb_field_get() refactoring
bcachefs: KEY_TYPE_error now counts towards i_sectors
bcachefs: Fix handling of unknown bkey types
bcachefs: Switch to unsafe_memcpy() in a few places
bcachefs: Use struct_size()
bcachefs: Correctly initialize new buckets on device resize
bcachefs: Fix another smatch complaint
bcachefs: Use strsep() in split_devs()
bcachefs: Add iops fields to bch_member
bcachefs: Rename bch_sb_field_members -> bch_sb_field_members_v1
bcachefs: New superblock section members_v2
bcachefs: Add new helper to retrieve bch_member from sb
bcachefs: bucket_lock() is now a sleepable lock
bcachefs: fix crc32c checksum merge byte order problem
bcachefs: Fix bch2_inode_delete_keys()
...
Coverity has noticed that the printing of error message in
register_cache() uses already freed bdev_handle to get to bdev. In fact
the problem has been there even before commit "bcache: Convert to
bdev_open_by_path()" just a bit more subtle one - cache object itself
could have been freed by the time we looked at ca->bdev and we don't
hold any reference to bdev either so even that could in principle go
away (due to device unplug or similar). Fix all these problems by
printing the error message before closing the bdev.
Fixes: dc893f51d24a ("bcache: Convert to bdev_open_by_path()")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231004093757.11560-1-jack@suse.cz
Asked-by: Coly Li <colyli@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Update DM core's normal IO submission to allocate required memory
using GFP_NOWAIT if REQ_NOWAIT is set.
Tested with simple test provided in commit a9ce385344 ("dm: don't
attempt to queue IO under RCU protection") that was enhanced to check
error codes. Also tested using fio's pvsync2 with nowait=1.
But testing with induced GFP_NOWAIT allocation failures wasn't
performed (yet).
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
alloc_multiple_bios() has the useful ability to try allocating bios
with GFP_NOWAIT but will fallback to using GFP_NOIO. The callers
service both empty flush bios and abnormal bios (e.g. discard).
alloc_multiple_bios() enhancements offered in this commit:
- don't require table_devices_lock if num_bios = 1
- allow caller to pass GFP_NOWAIT to do usual GFP_NOWAIT with GFP_NOIO
fallback
- allow caller to pass GFP_NOIO to _only_ allocate using GFP_NOIO
Flush bios with data may be issued to DM with REQ_NOWAIT, as such it
makes sense to attempt servicing them with GFP_NOWAIT allocations.
But abnormal IO should never be issued using REQ_NOWAIT (if that
changes in the future that's fine, but no sense supporting it now).
While at it, rename __send_changing_extent_only() to
__send_abnormal_io().
[Thanks to both Ming and Mikulas for help with translating known
possible IO scenarios to requirements.]
Suggested-by: Ming Lei <ming.lei@redhat.com>
Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
All the callers cast the value returned by __send_duplicate_bios to
unsigned int type, so we can return unsigned int as well.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
We expect `spec->target_type` to be NUL-terminated based on its use with
a format string after `dm_table_add_target()` is called
| r = dm_table_add_target(table, spec->target_type,
| (sector_t) spec->sector_start,
| (sector_t) spec->length,
| target_params);
... wherein `spec->target_type` is passed as parameter `type` and later
printed with DMERR:
| DMERR("%s: %s: unknown target type", dm_device_name(t->md), type);
It appears that `spec` is not zero-allocated and thus NUL-padding may be
required in this ioctl context.
Considering the above, a suitable replacement is `strscpy_pad` due to
the fact that it guarantees NUL-termination whilst maintaining the
NUL-padding behavior that strncpy provides.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://github.com/KSPP/linux/issues/90
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
It seems `cmd->policy_name` is intended to be NUL-terminated based on a
now changed line of code from Commit (c6b4fcbad0 "dm: add cache
target"):
| if (strcmp(cmd->policy_name, policy_name)) { // ...
However, now a length-bounded strncmp is used:
| if (strncmp(cmd->policy_name, policy_name, sizeof(cmd->policy_name)))
... which means NUL-terminated may not strictly be required. However, I
believe the intent of the code is clear and we should maintain
NUL-termination of policy_names.
Moreover, __begin_transaction_flags() zero-allocates `cmd` before
calling read_superblock_fields():
| cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
Also, `disk_super->policy_name` is zero-initialized
| memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name));
... therefore any NUL-padding is redundant.
Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
Remove sentinel from raid_table
Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
raid5 is the only personality to suspend array in check_reshape() and
start_reshape() callback, suspend and quiesce() callback can both wait
for all normal io to be done, and prevent new io to be dispatched, the
difference is that suspend is implemented in common layer, and quiesce()
callback is implemented in raid5.
In order to cleanup all the usage of mddev_suspend(), the new apis
__mddev_suspend() need to be called before 'reconfig_mutex' is held,
and it's not good to affect all the personalities in common layer just
for raid5. Hence replace suspend with quiesce() callaback, prepare to
reomove all the users of mddev_suspend().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-17-yukuai1@huaweicloud.com
User can write 'remove' and 're-add' to trigger array reconfiguration
through sysfs, suspend array in this case so that io won't concurrent
with array reconfiguration.
And now that all the caller of add_bound_rdev() alread suspend the
array, remove mddev_suspend/resume() from add_bound_rdev() as well.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-12-yukuai1@huaweicloud.com
The new helpers suspend the array first and then lock the array,
Prepare to refactor from:
mddev_lock/lock_nointr
mddev_suspend
...
mddev_resuem
mddev_lock
With:
mddev_suspend_and_lock/lock_nointr
...
mddev_unlock_and_resume
After all the use cases is refactored, mddev_suspend/resume() will be
removed.
And mddev_suspend_and_lock() will also replace mddev_lock() for the case
that the array will be reconfigured, in order to synchronize with io to
prevent problems in many corner cases.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-6-yukuai1@huaweicloud.com
Advantages for new apis:
- reconfig_mutex is not required;
- the weird logical that suspend array hold 'reconfig_mutex' for
mddev_check_recovery() to update superblock is not needed;
- the specail handling, 'pers->prepare_suspend', for raid456 is not
needed;
- It's safe to be called at any time once mddev is allocated, and it's
designed to be used from slow path where array configuration is changed;
- the new helpers is designed to be called before mddev_lock(), hence
it support to be interrupted by user as well.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-5-yukuai1@huaweicloud.com
Prepare to cleanup pers->prepare_suspend(), which is used to fix a
deadlock in raid456 by returning error for io that is waiting for
reshape to make progress in mddev_suspend().
This change will allow reshape to make progress while waiting for io to
be done in mddev_suspend() in following patches.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-4-yukuai1@huaweicloud.com
