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Move the CSI check into nvme_ns_report_zones to clean up the code
a little bit and prepare for further refactoring.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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Add the __releases annotation to tell sparse that nvme_ns_head_ctrl_ioctl
is expected to unlock head->srcu.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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nvme_ns_head_ctrl_ioctl is always used on multipath nodes, so just call
srcu_read_unlock directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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nvme_ns_head_ioctl is always used on multipath nodes, no need to
deal with the de-multiplexers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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nvme_ns_head_chr_ioctl is always used on multipath nodes, so just call
srcu_read_unlock and consolidate the two unlock paths.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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No need to use the braces around ~ operator.
No functionality change in this patch.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Remove the comment at the end of the switch that is not needed as
function is small enough.
No functionality change in this patch.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Remove the extra lines in the switch block that is not common practice
in the kernel code.
No functionality change in this patch.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Fix the comment style that matches existing code.
No functionality change in this patch.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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In our application, we need a way to force TCP connections to go out a
specific IP interface instead of letting Linux select the interface
based on the routing tables.
Add the 'host-iface' option to allow specifying the interface to use.
When the option host-iface is specified, the driver uses the specified
interface to set the option SO_BINDTODEVICE on the TCP socket before
connecting.
This new option is needed in addtion to the existing host-traddr for
the following reasons:
Specifying an IP interface by its associated IP address is less
intuitive than specifying the actual interface name and, in some cases,
simply doesn't work. That's because the association between interfaces
and IP addresses is not predictable. IP addresses can be changed or can
change by themselves over time (e.g. DHCP). Interface names are
predictable [1] and will persist over time. Consider the following
configuration.
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state ...
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 100.0.0.100/24 scope global lo
valid_lft forever preferred_lft forever
2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc ...
link/ether 08:00:27:21:65:ec brd ff:ff:ff:ff:ff:ff
inet 100.0.0.100/24 scope global enp0s3
valid_lft forever preferred_lft forever
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc ...
link/ether 08:00:27:4f:95:5c brd ff:ff:ff:ff:ff:ff
inet 100.0.0.100/24 scope global enp0s8
valid_lft forever preferred_lft forever
The above is a VM that I configured with the same IP address
(100.0.0.100) on all interfaces. Doing a reverse lookup to identify the
unique interface associated with 100.0.0.100 does not work here. And
this is why the option host_iface is required. I understand that the
above config does not represent a standard host system, but I'm using
this to prove a point: "We can never know how users will configure
their systems". By te way, The above configuration is perfectly fine
by Linux.
The current TCP implementation for host_traddr performs a
bind()-before-connect(). This is a common construct to set the source
IP address on a TCP socket before connecting. This has no effect on how
Linux selects the interface for the connection. That's because Linux
uses the Weak End System model as described in RFC1122 [2]. On the other
hand, setting the Source IP Address has benefits and should be supported
by linux-nvme. In fact, setting the Source IP Address is a mandatory
FedGov requirement (e.g. connection to a RADIUS/TACACS+ server).
Consider the following configuration.
$ ip addr list dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc ...
link/ether 08:00:27:4f:95:5c brd ff:ff:ff:ff:ff:ff
inet 192.168.56.101/24 brd 192.168.56.255 scope global enp0s8
valid_lft 426sec preferred_lft 426sec
inet 192.168.56.102/24 scope global secondary enp0s8
valid_lft forever preferred_lft forever
inet 192.168.56.103/24 scope global secondary enp0s8
valid_lft forever preferred_lft forever
inet 192.168.56.104/24 scope global secondary enp0s8
valid_lft forever preferred_lft forever
Here we can see that several addresses are associated with interface
enp0s8. By default, Linux always selects the default IP address,
192.168.56.101, as the source address when connecting over interface
enp0s8. Some users, however, want the ability to specify a different
source address (e.g., 192.168.56.102, 192.168.56.103, ...). The option
host_traddr can be used as-is to perform this function.
In conclusion, I believe that we need 2 options for TCP connections.
One that can be used to specify an interface (host-iface). And one that
can be used to set the source address (host-traddr). Users should be
allowed to use one or the other, or both, or none. Of course, the
documentation for host_traddr will need some clarification. It should
state that when used for TCP connection, this option only sets the
source address. And the documentation for host_iface should say that
this option is only available for TCP connections.
References:
[1] https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/
[2] https://tools.ietf.org/html/rfc1122
Tested both IPv4 and IPv6 connections.
Signed-off-by: Martin Belanger <martin.belanger@dell.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The documentation around the StorageD3Enable property hints that it
should be made on the PCI device. This is where newer AMD systems set
the property and it's required for S0i3 support.
So rather than look for nodes of the root port only present on Intel
systems, switch to the companion ACPI device for all systems.
David Box from Intel indicated this should work on Intel as well.
Link: https://lore.kernel.org/linux-nvme/YK6gmAWqaRmvpJXb@google.com/T/#m900552229fa455867ee29c33b854845fce80ba70
Link: https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/power-management-for-storage-hardware-devices-intro
Fixes: df4f9bc4fb9c ("nvme-pci: add support for ACPI StorageD3Enable property")
Suggested-by: Liang Prike <Prike.Liang@amd.com>
Acked-by: Raul E Rangel <rrangel@chromium.org>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The algorithm that was used until now for building the APST configuration
table has been found to produce entries with excessively long ITPT
(idle time prior to transition) for devices declaring relatively long
entry and exit latencies for non-operational power states. This leads
to unnecessary waste of power and, as a result, failure to pass
mandatory power consumption tests on Chromebook platforms.
The new algorithm is based on two predefined ITPT values and two
predefined latency tolerances. Based on these values, as well as on
exit and entry latencies reported by the device, the algorithm looks
for up to 2 suitable non-operational power states to use as primary
and secondary APST transition targets. The predefined values are
supplied to the nvme driver as module parameters:
- apst_primary_timeout_ms (default: 100)
- apst_secondary_timeout_ms (default: 2000)
- apst_primary_latency_tol_us (default: 15000)
- apst_secondary_latency_tol_us (default: 100000)
The algorithm echoes the approach used by Intel's and Microsoft's drivers
on Windows. The specific default parameter values are also based on those
drivers. Yet, this patch doesn't introduce the ability to dynamically
regenerate the APST table in the event of switching the power source from
AC to battery and back. Adding this functionality may be considered in the
future. In the meantime, the timeouts and tolerances reflect a compromise
between values used by Microsoft for AC and battery scenarios.
In most NVMe devices the new algorithm causes them to implement a more
aggressive power saving policy. While beneficial in most cases, this
sometimes comes at the price of a higher IO processing latency in certain
scenarios as well as at the price of a potential impact on the drive's
endurance (due to more frequent context saving when entering deep non-
operational states). So in order to provide a fallback for systems where
these regressions cannot be tolerated, the patch allows to revert to
the legacy behavior by setting either apst_primary_timeout_ms or
apst_primary_latency_tol_us parameter to 0. Eventually (and possibly after
fine tuning the default values of the module parameters) the legacy behavior
can be removed.
TESTING.
The new algorithm has been extensively tested. Initially, simulations were
used to compare APST tables generated by old and new algorithms for a wide
range of devices. After that, power consumption, performance and latencies
were measured under different workloads on devices from multiple vendors
(WD, Intel, Samsung, Hynix, Kioxia). Below is the description of the tests
and the findings.
General observations.
The effect the patch has on the APST table varies depending on the entry and
exit latencies advertised by the devices. For some devices, the effect is
negligible (e.g. Kioxia KBG40ZNS), for some significant, making the
transitions to PS3 and PS4 much quicker (e.g. WD SN530, Intel 760P), or making
the sleep deeper, PS4 rather than PS3 after a similar amount of time (e.g.
SK Hynix BC511). For some devices (e.g. Samsung PM991) the effect is mixed:
the initial transition happens after a longer idle time, but takes the device
to a lower power state.
Workflows.
In order to evaluate the patch's effect on the power consumption and latency,
7 workflows were used for each device. The workflows were designed to test
the scenarios where significant differences between the old and new behaviors
are most likely. Each workflow was tested twice: with the new and with the
old APST table generation implementation. Power consumption, performance and
latency were measured in the process. The following workflows were used:
1) Consecutive write at the maximum rate with IO depth of 2, with no pauses
2) Repeated pattern of 1000 consecutive writes of 4K packets followed by 50ms
idle time
3) Repeated pattern of 1000 consecutive writes of 4K packets followed by 150ms
idle time
4) Repeated pattern of 1000 consecutive writes of 4K packets followed by 500ms
idle time
5) Repeated pattern of 1000 consecutive writes of 4K packets followed by 1.5s
idle time
6) Repeated pattern of 1000 consecutive writes of 4K packets followed by 5s
idle time
7) Repeated pattern of a single random read of a 4K packet followed by 150ms
idle time
Power consumption
Actual power consumption measurements produced predictable results in
accordance with the APST mechanism's theory of operation.
Devices with long entry and exit latencies such as WD SN530 showed huge
improvement on scenarios 4,5 and 6 of up to 62%. Devices such as Kioxia
KBG40ZNS where the resulting APST table looks virtually identical with
both legacy and new algorithms, showed little or no change in the average power
consumption on all workflows. Devices with extra short latencies such as
Samsung PM991 showed moderate increase in power consumption of up to 18% in
worst case scenarios.
In addition, on Intel and Samsung devices a more complex impact was observed
on scenarios 3, 4 and 7. Our understanding is that due to longer stay in deep
non-operational states between the writes the devices start performing background
operations leading to an increase of power consumption. With the old APST tables
part of these operations are delayed until the scenario is over and a longer idle
period begins, but eventually this extra power is consumed anyway.
Performance.
In terms of performance measured on sustained write or read scenarios, the
effect of the patch is minimal as in this case the device doesn't enter low power
states.
Latency
As expected, in devices where the patch causes a more aggressive power saving
policy (e.g. WD SN530, Intel 760P), an increase in latency was observed in
certain scenarios. Workflow number 7, specifically designed to simulate the
worst case scenario as far as latency is concerned, indeed shows a sharp
increase in average latency (~2ms -> ~53ms on Intel 760P and 0.6 -> 10ms on
WD SN530). The latency increase on other workloads and other devices is much
milder or non-existent.
Signed-off-by: Alexey Bogoslavsky <alexey.bogoslavsky@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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The variable ret is being initialized with a value that is never read,
it is being updated later on. The assignment is redundant and can be
removed.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows
that, in the worst scenario, could lead to heap overflows.
This code was detected with the help of Coccinelle and, audited and
fixed manually.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20210513203730.GA212128@embeddedor
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The tags used for an IO scheduler are currently per hctx.
As such, when q->nr_hw_queues grows, so does the request queue total IO
scheduler tag depth.
This may cause problems for SCSI MQ HBAs whose total driver depth is
fixed.
Ming and Yanhui report higher CPU usage and lower throughput in scenarios
where the fixed total driver tag depth is appreciably lower than the total
scheduler tag depth:
https://lore.kernel.org/linux-block/440dfcfc-1a2c-bd98-1161-cec4d78c6dfc@huawei.com/T/#mc0d6d4f95275a2743d1c8c3e4dc9ff6c9aa3a76b
In that scenario, since the scheduler tag is got first, much contention
is introduced since a driver tag may not be available after we have got
the sched tag.
Improve this scenario by introducing request queue-wide tags for when
a tagset-wide sbitmap is used. The static sched requests are still
allocated per hctx, as requests are initialised per hctx, as in
blk_mq_init_request(..., hctx_idx, ...) ->
set->ops->init_request(.., hctx_idx, ...).
For simplicity of resizing the request queue sbitmap when updating the
request queue depth, just init at the max possible size, so we don't need
to deal with the possibly with swapping out a new sbitmap for old if
we need to grow.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/1620907258-30910-3-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The tag allocation code to alloc the sbitmap pairs is common for regular
bitmaps tags and shared sbitmap, so refactor into a common function.
Also remove superfluous "flags" argument from blk_mq_init_shared_sbitmap().
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/1620907258-30910-2-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Before we free request queue, clearing flush request reference in
tags->rqs[], so that potential UAF can be avoided.
Based on one patch written by David Jeffery.
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210511152236.763464-5-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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refcount_inc_not_zero() in bt_tags_iter() still may read one freed
request.
Fix the issue by the following approach:
1) hold a per-tags spinlock when reading ->rqs[tag] and calling
refcount_inc_not_zero in bt_tags_iter()
2) clearing stale request referred via ->rqs[tag] before freeing
request pool, the per-tags spinlock is held for clearing stale
->rq[tag]
So after we cleared stale requests, bt_tags_iter() won't observe
freed request any more, also the clearing will wait for pending
request reference.
The idea of clearing ->rqs[] is borrowed from John Garry's previous
patch and one recent David's patch.
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: David Jeffery <djeffery@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210511152236.763464-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter(), and
this way will prevent the request from being re-used when ->fn is
running. The approach is same as what we do during handling timeout.
Fix request use-after-free(UAF) related with completion race or queue
releasing:
- If one rq is referred before rq->q is frozen, then queue won't be
frozen before the request is released during iteration.
- If one rq is referred after rq->q is frozen, refcount_inc_not_zero()
will return false, and we won't iterate over this request.
However, still one request UAF not covered: refcount_inc_not_zero() may
read one freed request, and it will be handled in next patch.
Tested-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210511152236.763464-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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For flush request, rq->end_io() may be called two times, one is from
timeout handling(blk_mq_check_expired()), another is from normal
completion(__blk_mq_end_request()).
Move blk_account_io_flush() after flush_rq->ref drops to zero, so
io accounting can be done just once for flush request.
Fixes: b68663186577 ("block: add iostat counters for flush requests")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210511152236.763464-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Align to common code conventions.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20210511155319.1885277-1-mgurtovoy@nvidia.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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blkcg has always rejected to attach if any of the member tasks has shared
io_context. The rationale was that io_contexts can be shared across
different cgroups making it impossible to define what the appropriate
control behavior should be. However, this check causes more problems than it
solves:
* The check prevents controller enable and migrations but not CLONE_IO
itself, which can lead to surprises as the outcome changes depending on
the order of operations.
* Sharing within a cgroup is fine but the check can't distinguish that. This
leads to unnecessary conflicts with the recent CLONE_IO usage in io_uring.
io_context sharing doesn't make any difference for rq_qos based controllers
and the way it's used is safe as long as tasks aren't migrated dynamically
which is the vast majority of use cases. While we can try to make the check
more precise to avoid false positives, the added complexity doesn't seem
worthwhile. Let's just drop blkcg_can_attach().
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/YJrTvHbrRDbJjw+S@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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The mutex ktio_spawn_lock is initialized statically.
It is unnecessary to initialize by mutex_init().
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210511113440.3772053-1-yangyingliang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Now block_dump feature is gone, remove all comments in docs.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210313030146.2882027-4-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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We have already delete block_dump feature in mark_inode_dirty() because
it can be replaced by tracepoints, now we also remove the part in
submit_bio() for the same reason. The part of block dump feature in
submit_bio() dump the write process, write region and sectors on the
target disk into kernel message. it can be replaced by
block_bio_queue tracepoint in submit_bio_checks(), so we do not need
block_dump anymore, remove the whole block_dump feature.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210313030146.2882027-3-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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block_dump is an old debugging interface, one of it's functions is used
to print the information about who write which file on disk. If we
enable block_dump through /proc/sys/vm/block_dump and turn on debug log
level, we can gather information about write process name, target file
name and disk from kernel message. This feature is realized in
block_dump___mark_inode_dirty(), it print above information into kernel
message directly when marking inode dirty, so it is noisy and can easily
trigger log storm. At the same time, get the dentry refcount is also not
safe, we found it will lead to deadlock on ext4 file system with
data=journal mode.
After tracepoints has been introduced into the kernel, we got a
tracepoint in __mark_inode_dirty(), which is a better replacement of
block_dump___mark_inode_dirty(). The only downside is that it only trace
the inode number and not a file name, but it probably doesn't matter
because the original printed file name in block_dump is not accurate in
some cases, and we can still find it through the inode number and device
id. So this patch delete the dirting inode part of block_dump feature.
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210313030146.2882027-2-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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In commit d6995da31122 ("hugetlb: use page.private for hugetlb specific
page flags") the use of PagePrivate to indicate a reservation count
should be restored at free time was changed to the hugetlb specific flag
HPageRestoreReserve. Changes to a userfaultfd error path as well as a
VM_BUG_ON() in remove_inode_hugepages() were overlooked.
Users could see incorrect hugetlb reserve counts if they experience an
error with a UFFDIO_COPY operation. Specifically, this would be the
result of an unlikely copy_huge_page_from_user error. There is not an
increased chance of hitting the VM_BUG_ON.
Link: https://lkml.kernel.org/r/20210521233952.236434-1-mike.kravetz@oracle.com
Fixes: d6995da31122 ("hugetlb: use page.private for hugetlb specific page flags")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Mina Almasry <almasry.mina@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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lib/bitfield_kunit.c: In function `test_bitfields_constants':
lib/bitfield_kunit.c:93:1: warning: the frame size of 7456 bytes is larger than 2048 bytes [-Wframe-larger-than=]
}
^
As the description of BITFIELD_KUNIT in lib/Kconfig.debug, it "Only useful
for kernel devs running the KUnit test harness, and not intended for
inclusion into a production build". Therefore, it is not worth modifying
variable 'test_bitfields_constants' to clear this warning. Just suppress
it.
Link: https://lkml.kernel.org/r/20210518094533.7652-1-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Vitor Massaru Iha <vitor@massaru.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
People Cc me and I don't have time.
Link: https://lkml.kernel.org/r/YKarMxHJBIhMHQIh@localhost.localdomain
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
GENMASK() has an input check which uses __builtin_choose_expr() to
enable a compile time sanity check of its inputs if they are known at
compile time.
However, it turns out that __builtin_constant_p() does not always return
a compile time constant [0]. It was thought this problem was fixed with
gcc 4.9 [1], but apparently this is not the case [2].
Switch to use __is_constexpr() instead which always returns a compile time
constant, regardless of its inputs.
Link: https://lore.kernel.org/lkml/42b4342b-aefc-a16a-0d43-9f9c0d63ba7a@rasmusvillemoes.dk [0]
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=19449 [1]
Link: https://lore.kernel.org/lkml/1ac7bbc2-45d9-26ed-0b33-bf382b8d858b@I-love.SAKURA.ne.jp [2]
Link: https://lkml.kernel.org/r/20210511203716.117010-1-rikard.falkeborn@gmail.com
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Commit 9bf3bc949f8a ("watchdog: cleanup handling of false positives")
tried to handle a virtual host stopped by the host a more
straightforward and cleaner way.
But it introduced a risk of false softlockup reports. The virtual host
might be stopped at any time, for example between
kvm_check_and_clear_guest_paused() and is_softlockup(). As a result,
is_softlockup() might read the updated jiffies and detects a softlockup.
A solution might be to put back kvm_check_and_clear_guest_paused() after
is_softlockup() and detect it. But it would put back the cycle that
complicates the logic.
In fact, the handling of all the timestamps is not reliable. The code
does not guarantee when and how many times the timestamps are read. For
example, "period_ts" might be touched anytime also from NMI and re-read in
is_softlockup(). It works just by chance.
Fix all the problems by making the code even more explicit.
1. Make sure that "now" and "period_ts" timestamps are read only once.
They might be changed at anytime by NMI or when the virtual guest is
stopped by the host. Note that "now" timestamp does this implicitly
because "jiffies" is marked volatile.
2. "now" time must be read first. The state of "period_ts" will
decide whether it will be used or the period will get restarted.
3. kvm_check_and_clear_guest_paused() must be called before reading
"period_ts". It touches the variable when the guest was stopped.
As a result, "now" timestamp is used only when the watchdog was not
touched and the guest not stopped in the meantime. "period_ts" is
restarted in all other situations.
Link: https://lkml.kernel.org/r/YKT55gw+RZfyoFf7@alley
Fixes: 9bf3bc949f8aeefeacea4b ("watchdog: cleanup handling of false positives")
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reported-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
With CONFIG_DEBUG_PAGEALLOC enabled, the kernel should also untag the
object pointer, as done in get_freepointer().
Failing to do so reportedly leads to SLUB freelist corruptions that
manifest as boot-time crashes.
Link: https://lkml.kernel.org/r/20210514072228.534418-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Elliot Berman <eberman@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Fix the link error by adding '-static':
gcc -Wall -Wl,-z,max-page-size=0x1000 -pie load_address.c -o /home/yang/linux/tools/testing/selftests/exec/load_address_4096
/usr/bin/ld: /tmp/ccopEGun.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `stderr@@GLIBC_2.17' which may bind externally can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: /tmp/ccopEGun.o(.text+0x158): unresolvable R_AARCH64_ADR_PREL_PG_HI21 relocation against symbol `stderr@@GLIBC_2.17'
/usr/bin/ld: final link failed: bad value
collect2: error: ld returned 1 exit status
make: *** [Makefile:25: tools/testing/selftests/exec/load_address_4096] Error 1
Link: https://lkml.kernel.org/r/20210514092422.2367367-1-yangyingliang@huawei.com
Fixes: 206e22f01941 ("tools/testing/selftests: add self-test for verifying load alignment")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Cc: Chris Kennelly <ckennelly@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
do_mq_timedreceive calls wq_sleep with a stack local address. The
sender (do_mq_timedsend) uses this address to later call pipelined_send.
This leads to a very hard to trigger race where a do_mq_timedreceive
call might return and leave do_mq_timedsend to rely on an invalid
address, causing the following crash:
RIP: 0010:wake_q_add_safe+0x13/0x60
Call Trace:
__x64_sys_mq_timedsend+0x2a9/0x490
do_syscall_64+0x80/0x680
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f5928e40343
The race occurs as:
1. do_mq_timedreceive calls wq_sleep with the address of `struct
ext_wait_queue` on function stack (aliased as `ewq_addr` here) - it
holds a valid `struct ext_wait_queue *` as long as the stack has not
been overwritten.
2. `ewq_addr` gets added to info->e_wait_q[RECV].list in wq_add, and
do_mq_timedsend receives it via wq_get_first_waiter(info, RECV) to call
__pipelined_op.
3. Sender calls __pipelined_op::smp_store_release(&this->state,
STATE_READY). Here is where the race window begins. (`this` is
`ewq_addr`.)
4. If the receiver wakes up now in do_mq_timedreceive::wq_sleep, it
will see `state == STATE_READY` and break.
5. do_mq_timedreceive returns, and `ewq_addr` is no longer guaranteed
to be a `struct ext_wait_queue *` since it was on do_mq_timedreceive's
stack. (Although the address may not get overwritten until another
function happens to touch it, which means it can persist around for an
indefinite time.)
6. do_mq_timedsend::__pipelined_op() still believes `ewq_addr` is a
`struct ext_wait_queue *`, and uses it to find a task_struct to pass to
the wake_q_add_safe call. In the lucky case where nothing has
overwritten `ewq_addr` yet, `ewq_addr->task` is the right task_struct.
In the unlucky case, __pipelined_op::wake_q_add_safe gets handed a
bogus address as the receiver's task_struct causing the crash.
do_mq_timedsend::__pipelined_op() should not dereference `this` after
setting STATE_READY, as the receiver counterpart is now free to return.
Change __pipelined_op to call wake_q_add_safe on the receiver's
task_struct returned by get_task_struct, instead of dereferencing `this`
which sits on the receiver's stack.
As Manfred pointed out, the race potentially also exists in
ipc/msg.c::expunge_all and ipc/sem.c::wake_up_sem_queue_prepare. Fix
those in the same way.
Link: https://lkml.kernel.org/r/20210510102950.12551-1-varad.gautam@suse.com
Fixes: c5b2cbdbdac563 ("ipc/mqueue.c: update/document memory barriers")
Fixes: 8116b54e7e23ef ("ipc/sem.c: document and update memory barriers")
Fixes: 0d97a82ba830d8 ("ipc/msg.c: update and document memory barriers")
Signed-off-by: Varad Gautam <varad.gautam@suse.com>
Reported-by: Matthias von Faber <matthias.vonfaber@aox-tech.de>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
While reviewing [1] I came across commit d3378e86d182 ("mm/gup: check
page posion status for coredump.") and noticed that this patch is broken
in two ways. First it doesn't really prevent hwpoison pages from being
dumped because hwpoison pages can be marked asynchornously at any time
after the check. Secondly, and more importantly, the patch introduces a
ref count leak because get_dump_page takes a reference on the page which
is not released.
It also seems that the patch was merged incorrectly because there were
follow up changes not included as well as discussions on how to address
the underlying problem [2]
Therefore revert the original patch.
Link: http://lkml.kernel.org/r/20210429122519.15183-4-david@redhat.com [1]
Link: http://lkml.kernel.org/r/57ac524c-b49a-99ec-c1e4-ef5027bfb61b@redhat.com [2]
Link: https://lkml.kernel.org/r/20210505135407.31590-1-mhocko@kernel.org
Fixes: d3378e86d182 ("mm/gup: check page posion status for coredump.")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Aili Yao <yaoaili@kingsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
clang sometimes decides not to inline shuffle_zone(), but it calls a
__meminit function. Without the extra __meminit annotation we get this
warning:
WARNING: modpost: vmlinux.o(.text+0x2a86d4): Section mismatch in reference from the function shuffle_zone() to the function .meminit.text:__shuffle_zone()
The function shuffle_zone() references
the function __meminit __shuffle_zone().
This is often because shuffle_zone lacks a __meminit
annotation or the annotation of __shuffle_zone is wrong.
shuffle_free_memory() did not show the same problem in my tests, but it
could happen in theory as well, so mark both as __meminit.
Link: https://lkml.kernel.org/r/20210514135952.2928094-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
When multiple PCI devices get assigned to a guest right at boot, libxl
incrementally populates the backend tree. The writes for the first of
the devices trigger the backend watch. In turn xen_pcibk_setup_backend()
will set the XenBus state to Initialised, at which point no further
reconfigures would happen unless a device got hotplugged. Arrange for
reconfigure to also get triggered from the backend watch handler.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/2337cbd6-94b9-4187-9862-c03ea12e0c61@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
|
|
The commit referenced below was incomplete: It merely affected what
would get written to the vdev-<N> xenstore node. The guest would still
find the function at the original function number as long as
__xen_pcibk_get_pci_dev() wouldn't be in sync. The same goes for AER wrt
__xen_pcibk_get_pcifront_dev().
Undo overriding the function to zero and instead make sure that VFs at
function zero remain alone in their slot. This has the added benefit of
improving overall capacity, considering that there's only a total of 32
slots available right now (PCI segment and bus can both only ever be
zero at present).
Fixes: 8a5248fe10b1 ("xen PV passthru: assign SR-IOV virtual functions to separate virtual slots")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/8def783b-404c-3452-196d-3f3fd4d72c9e@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
|
|
xen_setup_gdt(), via xen_load_gdt_boot(), wants to adjust page tables.
For this to work when NX is not available, x86_configure_nx() needs to
be called first.
[jgross] Note that this is a revert of 36104cb9012a82e73 ("x86/xen:
Delay get_cpu_cap until stack canary is established"), which is possible
now that we no longer support running as PV guest in 32-bit mode.
Cc: <stable.vger.kernel.org> # 5.9
Fixes: 36104cb9012a82e73 ("x86/xen: Delay get_cpu_cap until stack canary is established")
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/12a866b0-9e89-59f7-ebeb-a2a6cec0987a@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
|
|
[ 612.157429] ==================================================================
[ 612.158275] BUG: KASAN: use-after-free in process_one_work+0x90/0x9b0
[ 612.158801] Read of size 8 at addr ffff88810a31ca60 by task kworker/2:9/2382
[ 612.159611] CPU: 2 PID: 2382 Comm: kworker/2:9 Tainted: G
OE 5.13.0-rc2+ #98
[ 612.159623] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.14.0-1.fc33 04/01/2014
[ 612.159640] Workqueue: 0x0 (deferredclose)
[ 612.159669] Call Trace:
[ 612.159685] dump_stack+0xbb/0x107
[ 612.159711] print_address_description.constprop.0+0x18/0x140
[ 612.159733] ? process_one_work+0x90/0x9b0
[ 612.159743] ? process_one_work+0x90/0x9b0
[ 612.159754] kasan_report.cold+0x7c/0xd8
[ 612.159778] ? lock_is_held_type+0x80/0x130
[ 612.159789] ? process_one_work+0x90/0x9b0
[ 612.159812] kasan_check_range+0x145/0x1a0
[ 612.159834] process_one_work+0x90/0x9b0
[ 612.159877] ? pwq_dec_nr_in_flight+0x110/0x110
[ 612.159914] ? spin_bug+0x90/0x90
[ 612.159967] worker_thread+0x3b6/0x6c0
[ 612.160023] ? process_one_work+0x9b0/0x9b0
[ 612.160038] kthread+0x1dc/0x200
[ 612.160051] ? kthread_create_worker_on_cpu+0xd0/0xd0
[ 612.160092] ret_from_fork+0x1f/0x30
[ 612.160399] Allocated by task 2358:
[ 612.160757] kasan_save_stack+0x1b/0x40
[ 612.160768] __kasan_kmalloc+0x9b/0xd0
[ 612.160778] cifs_new_fileinfo+0xb0/0x960 [cifs]
[ 612.161170] cifs_open+0xadf/0xf20 [cifs]
[ 612.161421] do_dentry_open+0x2aa/0x6b0
[ 612.161432] path_openat+0xbd9/0xfa0
[ 612.161441] do_filp_open+0x11d/0x230
[ 612.161450] do_sys_openat2+0x115/0x240
[ 612.161460] __x64_sys_openat+0xce/0x140
When mod_delayed_work is called to modify the delay of pending work,
it might return false and queue a new work when pending work is
already scheduled or when try to grab pending work failed.
So, Increase the reference count when new work is scheduled to
avoid use-after-free.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
These ioctl definitions in xfs_fs.h are part of the userspace ABI and
were mistakenly removed during the 5.13 merge window.
Fixes: 9fefd5db08ce ("xfs: convert to fileattr")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
|
|
sc->ip is the inode that's being scrubbed, which means that it's not set
for scrub types that don't involve inodes. If one of those scrubbers
(e.g. inode btrees) returns EDEADLOCK, we'll trip over the null pointer.
Fix that by reporting either the file being examined or the file that
was used to call scrub.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
|
|
If a realtime allocation fails because we can't find a sufficiently
large free extent satisfying locality rules, relax the locality rules
and try again. This reduces the occurrence of short writes to realtime
files when the write size is large and the free space is fragmented.
This was originally discovered by running generic/186 with the realtime
reflink patchset and a 128k cow extent size hint, but the short write
symptoms can manifest with a 128k extent size hint and no reflink, so
apply the fix now.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
|
|
The scv implementation missed updating syscall return value and error
value get/set functions to deal with the changed register ABI. This
broke ptrace PTRACE_GET_SYSCALL_INFO as well as some kernel auditing
and tracing functions.
Fix. tools/testing/selftests/ptrace/get_syscall_info now passes when
scv is used.
Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: "Dmitry V. Levin" <ldv@altlinux.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210520111931.2597127-2-npiggin@gmail.com
|
|
The sc and scv 0 system calls have different ABI conventions, and
ptracers need to know which system call type is being used if they want
to look at the syscall registers.
Document that pt_regs.trap can be used for this, and fix one in-tree user
to work with scv 0 syscalls.
Fixes: 7fa95f9adaee ("powerpc/64s: system call support for scv/rfscv instructions")
Cc: stable@vger.kernel.org # v5.9+
Reported-by: "Dmitry V. Levin" <ldv@altlinux.org>
Suggested-by: "Dmitry V. Levin" <ldv@altlinux.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210520111931.2597127-1-npiggin@gmail.com
|
|
When BLKRRPART is called concurrently with del_gendisk, the partitions
rescan can create a stale partition that will never be be cleaned up.
Fix this by checking the the disk is up before rescanning partitions
while under bd_mutex.
Signed-off-by: Gulam Mohamed <gulam.mohamed@oracle.com>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210514131842.1600568-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
As an artifact of how gendisk lookup used to work in earlier kernels,
GENHD_FL_UP is only cleared very late in del_gendisk, and a global lock
is used to prevent opens from succeeding while del_gendisk is tearing
down the gendisk. Switch to clearing the flag early and under bd_mutex
so that callers can use bd_mutex to stabilize the flag, which removes
the need for the global mutex.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210514131842.1600568-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
When multiple processes write data to the same block group on a
compressed zoned filesystem, the underlying device could report I/O
errors and data corruption is possible.
This happens because on a zoned file system, compressed data writes
where sent to the device via a REQ_OP_WRITE instead of a
REQ_OP_ZONE_APPEND operation. But with REQ_OP_WRITE and parallel
submission it cannot be guaranteed that the data is always submitted
aligned to the underlying zone's write pointer.
The change to using REQ_OP_ZONE_APPEND instead of REQ_OP_WRITE on a
zoned filesystem is non intrusive on a regular file system or when
submitting to a conventional zone on a zoned filesystem, as it is
guarded by btrfs_use_zone_append.
Reported-by: David Sterba <dsterba@suse.com>
Fixes: 9d294a685fbc ("btrfs: zoned: enable to mount ZONED incompat flag")
CC: stable@vger.kernel.org # 5.12.x: e380adfc213a13: btrfs: zoned: pass start block to btrfs_use_zone_append
CC: stable@vger.kernel.org # 5.12.x
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
btrfs_use_zone_append only needs the passed in extent_map's block_start
member, so there's no need to pass in the full extent map.
This also enables the use of btrfs_use_zone_append in places where we only
have a start byte but no extent_map.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
Christoph Hellwig
Chaitanya Kulkarni
Martin Belanger
Mario Limonciello
Alexey Bogoslavsky
Colin Ian King
Gustavo A. R. Silva
John Garry
Ming Lei
Max Gurtovoy
Tejun Heo
Yang Yingliang
zhangyi (F)
Linus Torvalds
Mike Kravetz
Zhen Lei
Alexey Dobriyan
Rikard Falkeborn
Petr Mladek
Alexander Potapenko
Varad Gautam
Michal Hocko
Arnd Bergmann
Jan Beulich
Rohith Surabattula
Darrick J. Wong
Nicholas Piggin
Gulam Mohamed
Johannes Thumshirn