Patch series "add max arg to swappiness in memory.reclaim and lru_gen", v4.
This patchset adds max arg to swappiness in memory.reclaim and lru_gen for
anon only proactive memory reclaim.
With commit <68cd9050d871> ("mm: add swappiness= arg to memory.reclaim")
we can submit an additional swappiness=<val> argument to memory.reclaim.
It is very useful because we can dynamically adjust the reclamation ratio
based on the anonymous folios and file folios of each cgroup. For
example,when swappiness is set to 0, we only reclaim from file folios.
But we can not relciam memory just from anon folios.
This patchset introduces a new macro, SWAPPINESS_ANON_ONLY, defined as
MAX_SWAPPINESS + 1, represent the max arg semantics. It specifically
indicates that reclamation should occur only from anonymous pages.
Patch 1 adds swappiness=max arg to memory.reclaim suggested-by: Yosry
Ahmed
Patch 2 add more comments for cache_trim_mode from Johannes Weiner in [1].
Patch 3 add max arg to lru_gen for proactive memory reclaim in MGLRU. The
MGLRU already supports reclaiming exclusively from anonymous pages. This
patch formalizes that behavior by introducing a max parameter to represent
the corresponding semantics.
Patch 4 using SWAPPINESS_ANON_ONLY in MGLRU Using SWAPPINESS_ANON_ONLY
instead of MAX_SWAPPINESS + 1 to indicate reclaiming only from anonymous
pages makes the code more readable and explicit
Here is the previous discussion:
https://lore.kernel.org/all/20250314033350.1156370-1-hezhongkun.hzk@bytedance.com/https://lore.kernel.org/all/20250312094337.2296278-1-hezhongkun.hzk@bytedance.com/https://lore.kernel.org/all/20250318135330.3358345-1-hezhongkun.hzk@bytedance.com/
This patch (of 4):
With commit <68cd9050d871> ("mm: add swappiness= arg to memory.reclaim")
we can submit an additional swappiness=<val> argument to memory.reclaim.
It is very useful because we can dynamically adjust the reclamation ratio
based on the anonymous folios and file folios of each cgroup. For
example,when swappiness is set to 0, we only reclaim from file folios.
However,we have also encountered a new issue: when swappiness is set to
the MAX_SWAPPINESS, it may still only reclaim file folios.
So, we hope to add a new arg 'swappiness=max' in memory.reclaim where
proactive memory reclaim only reclaims from anonymous folios when
swappiness is set to max. The swappiness semantics from a user
perspective remain unchanged.
For example, something like this:
echo "2M swappiness=max" > /sys/fs/cgroup/memory.reclaim
will perform reclaim on the rootcg with a swappiness setting of 'max' (a
new mode) regardless of the file folios. Users have a more comprehensive
view of the application's memory distribution because there are many
metrics available. For example, if we find that a certain cgroup has a
large number of inactive anon folios, we can reclaim only those and skip
file folios, because with the zram/zswap, the IO tradeoff that
cache_trim_mode or other file first logic is making doesn't hold - file
refaults will cause IO, whereas anon decompression will not.
With this patch, the swappiness argument of memory.reclaim has a new
mode 'max', means reclaiming just from anonymous folios both in traditional
LRU and MGLRU.
Link: https://lkml.kernel.org/r/cover.1745225696.git.hezhongkun.hzk@bytedance.com
Link: https://lore.kernel.org/all/20250314141833.GA1316033@cmpxchg.org/ [1]
Link: https://lkml.kernel.org/r/519e12b9b1f8c31a01e228c8b4b91a2419684f77.1745225696.git.hezhongkun.hzk@bytedance.com
Signed-off-by: Zhongkun He <hezhongkun.hzk@bytedance.com>
Suggested-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Acked-by: Muchun Song <muchun.song@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Setting the max and high limits can trigger synchronous reclaim and/or
oom-kill if the usage is higher than the given limit. This behavior is
fine for newly created cgroups but it can cause issues for the node
controller while setting limits for existing cgroups.
In our production multi-tenant and overcommitted environment, we are
seeing priority inversion when the node controller dynamically adjusts the
limits of running jobs of different priorities. Based on the system
situation, the node controller may reduce the limits of lower priority
jobs and increase the limits of higher priority jobs. However we are
seeing node controller getting stuck for long period of time while
reclaiming from lower priority jobs while setting their limits and also
spends a lot of its own CPU.
One of the workaround we are trying is to fork a new process which sets
the limit of the lower priority job along with setting an alarm to get
itself killed if it get stuck in the reclaim for lower priority job.
However we are finding it very unreliable and costly. Either we need a
good enough time buffer for the alarm to be delivered after setting limit
and potentialy spend a lot of CPU in the reclaim or be unreliable in
setting the limit for much shorter but cheaper (less reclaim) alarms.
Let's introduce new limit setting option which does not trigger reclaim
and/or oom-kill and let the processes in the target cgroup to trigger
reclaim and/or throttling and/or oom-kill in their next charge request.
This will make the node controller on multi-tenant overcommitted
environment much more reliable.
Explanation from Johannes on side-effects of O_NONBLOCK limit change:
It's usually the allocating tasks inside the group bearing the cost of
limit enforcement and reclaim. This allows a (privileged) updater from
outside the group to keep that cost in there - instead of having to
help, from a context that doesn't necessarily make sense.
I suppose the tradeoff with that - and the reason why this was doing
sync reclaim in the first place - is that, if the group is idle and
not trying to allocate more, it can take indefinitely for the new
limit to actually be met.
It should be okay in most scenarios in practice. As the capacity is
reallocated from group A to B, B will exert pressure on A once it
tries to claim it and thereby shrink it down. If A is idle, that
shouldn't be hard. If A is running, it's likely to fault/allocate
soon-ish and then join the effort.
It does leave a (malicious) corner case where A is just busy-hitting
its memory to interfere with the clawback. This is comparable to
reclaiming memory.low overage from the outside, though, which is an
acceptable risk. Users of O_NONBLOCK just need to be aware.
Link: https://lkml.kernel.org/r/20250419183545.1982187-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard
regions", v2.
Introduce the PAGE_IS_GUARD flag in the PAGEMAP_SCAN ioctl to expose
information about guard regions. This allows userspace tools, such as
CRIU, to detect and handle guard regions.
Currently, CRIU utilizes PAGEMAP_SCAN as a more efficient alternative to
parsing /proc/pid/pagemap. Without this change, guard regions are
incorrectly reported as swap-anon regions, leading CRIU to attempt dumping
them and subsequently failing.
The series includes updates to the documentation and selftests to reflect
the new functionality.
This patch (of 3):
Introduce the PAGE_IS_GUARD flag in the PAGEMAP_SCAN ioctl to expose
information about guard regions. This allows userspace tools, such as
CRIU, to detect and handle guard regions.
Link: https://lkml.kernel.org/r/20250324065328.107678-1-avagin@google.com
Link: https://lkml.kernel.org/r/20250324065328.107678-2-avagin@google.com
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The writeback interface supports a page_index=N parameter which performs
writeback of the given page. Since we rarely need to writeback just one
single page, the typical use case involves a number of writeback calls,
each performing writeback of one page:
echo page_index=100 > zram0/writeback
...
echo page_index=200 > zram0/writeback
echo page_index=500 > zram0/writeback
...
echo page_index=700 > zram0/writeback
One obvious downside of this is that it increases the number of syscalls.
Less obvious, but a significantly more important downside, is that when
given only one page to post-process zram cannot perform an optimal target
selection. This becomes a critical limitation when writeback_limit is
enabled, because under writeback_limit we want to guarantee the highest
memory savings hence we first need to writeback pages that release the
highest amount of zsmalloc pool memory.
This patch adds page_indexes=LOW-HIGH parameter to the writeback
interface:
echo page_indexes=100-200 page_indexes=500-700 > zram0/writeback
This gives zram a chance to apply an optimal target selection strategy on
each iteration of the writeback loop.
We also now permit multiple page_index parameters per call (previously
zram would recognize only one page_index) and a mix or single pages and
page ranges:
echo page_index=42 page_index=99 page_indexes=100-200 \
page_indexes=500-700 > zram0/writeback
Apart from that the patch also unifies parameters passing and resembles
other "modern" zram device attributes (e.g. recompression), while the old
interface used a mixed scheme: values-less parameters for mode and a
key=value format for page_index. We still support the "old" value-less
format for compatibility reasons.
[senozhatsky@chromium.org: simplify parse_page_index() range checks, per Brian]
nk: https://lkml.kernel.org/r/20250404015327.2427684-1-senozhatsky@chromium.org
[sozhatsky@chromium.org: fix uninitialized variable in zram_writeback_slots(), per Dan]
nk: https://lkml.kernel.org/r/20250409112611.1154282-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20250327015818.4148660-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Richard Chang <richardycc@google.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When retpoline mitigation is enabled for spectre-v2, enabling
call-depth-tracking and RSB stuffing also mitigates ITS. Add cmdline option
indirect_target_selection=stuff to allow enabling RSB stuffing mitigation.
When retpoline mitigation is not enabled, =stuff option is ignored, and
default mitigation for ITS is deployed.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Ice Lake generation CPUs are not affected by guest/host isolation part of
ITS. If a user is only concerned about KVM guests, they can now choose a
new cmdline option "vmexit" that will not deploy the ITS mitigation when
CPU is not affected by guest/host isolation. This saves the performance
overhead of ITS mitigation on Ice Lake gen CPUs.
When "vmexit" option selected, if the CPU is affected by ITS guest/host
isolation, the default ITS mitigation is deployed.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Indirect Target Selection (ITS) is a bug in some pre-ADL Intel CPUs with
eIBRS. It affects prediction of indirect branch and RETs in the
lower half of cacheline. Due to ITS such branches may get wrongly predicted
to a target of (direct or indirect) branch that is located in the upper
half of the cacheline.
Scope of impact
===============
Guest/host isolation
--------------------
When eIBRS is used for guest/host isolation, the indirect branches in the
VMM may still be predicted with targets corresponding to branches in the
guest.
Intra-mode
----------
cBPF or other native gadgets can be used for intra-mode training and
disclosure using ITS.
User/kernel isolation
---------------------
When eIBRS is enabled user/kernel isolation is not impacted.
Indirect Branch Prediction Barrier (IBPB)
-----------------------------------------
After an IBPB, indirect branches may be predicted with targets
corresponding to direct branches which were executed prior to IBPB. This is
mitigated by a microcode update.
Add cmdline parameter indirect_target_selection=off|on|force to control the
mitigation to relocate the affected branches to an ITS-safe thunk i.e.
located in the upper half of cacheline. Also add the sysfs reporting.
When retpoline mitigation is deployed, ITS safe-thunks are not needed,
because retpoline sequence is already ITS-safe. Similarly, when call depth
tracking (CDT) mitigation is deployed (retbleed=stuff), ITS safe return
thunk is not used, as CDT prevents RSB-underflow.
To not overcomplicate things, ITS mitigation is not supported with
spectre-v2 lfence;jmp mitigation. Moreover, it is less practical to deploy
lfence;jmp mitigation on ITS affected parts anyways.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Turn the default 5 second test delay for hibernation into a
configurable module parameter, so users can determine how
long to wait in this pseudo-hibernate state before resuming
the system.
The configurable delay parameter has been added for suspend, so
add an analogous one for hibernation.
Example (wait 30 seconds);
# echo 30 > /sys/module/hibernate/parameters/pm_test_delay
# echo core > /sys/power/pm_test
Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patch.msgid.link/20250507063520.419635-1-zhangzihuan@kylinos.cn
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce a mount option to allow sysadmins to specify the maximum size
of an atomic write. If the filesystem can work with the supplied value,
that becomes the new guaranteed maximum.
The value mustn't be too big for the existing filesystem geometry (max
write size, max AG/rtgroup size). We dynamically recompute the
tr_atomic_write transaction reservation based on the given block size,
check that the current log size isn't less than the new minimum log size
constraints, and set a new maximum.
The actual software atomic write max is still computed based off of
tr_atomic_ioend the same way it has for the past few commits. Note also
that xfs_calc_atomic_write_log_geometry is non-static because mkfs will
need that.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Commit a3e8fe814a ("x86/build: Raise the minimum GCC version to 8.1")
raised the minimum compiler version as enforced by Kbuild to gcc-8.1
and clang-15 for x86.
This is actually the same gcc version that has been discussed as the
minimum for all architectures several times in the past, with little
objection. A previous concern was the kernel for SLE15-SP7 needing to
be built with gcc-7. As this ended up still using linux-6.4 and there
is no plan for an SP8, this is no longer a problem.
Change it for all architectures and adjust the documentation accordingly.
A few version checks can be removed in the process. The binutils
version 2.30 is the lowest version used in combination with gcc-8 on
common distros, so use that as the corresponding minimum.
Link: https://lore.kernel.org/lkml/20240925150059.3955569-32-ardb+git@google.com/
Link: https://lore.kernel.org/lkml/871q7yxrgv.wl-tiwai@suse.de/
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
With commit dcbb01fbb7 ("x86/pci: Remove old STA2x11 support"), the
STA2X11 Video Input Port driver is not needed and cannot be built anymore.
Remove the driver and its reference in media documentation.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Remove the duplicated section and while at it, turn spaces into tabs.
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Fixes: c7b67ddc3c ("xfs: document zoned rt specifics in admin-guide")
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Old microcode is bad for users and for kernel developers.
For users, it exposes them to known fixed security and/or functional
issues. These obviously rarely result in instant dumpster fires in
every environment. But it is as important to keep your microcode up
to date as it is to keep your kernel up to date.
Old microcode also makes kernels harder to debug. A developer looking
at an oops need to consider kernel bugs, known CPU issues and unknown
CPU issues as possible causes. If they know the microcode is up to
date, they can mostly eliminate known CPU issues as the cause.
Make it easier to tell if CPU microcode is out of date. Add a list
of released microcode. If the loaded microcode is older than the
release, tell users in a place that folks can find it:
/sys/devices/system/cpu/vulnerabilities/old_microcode
Tell kernel kernel developers about it with the existing taint
flag:
TAINT_CPU_OUT_OF_SPEC
== Discussion ==
When a user reports a potential kernel issue, it is very common
to ask them to reproduce the issue on mainline. Running mainline,
they will (independently from the distro) acquire a more up-to-date
microcode version list. If their microcode is old, they will
get a warning about the taint and kernel developers can take that
into consideration when debugging.
Just like any other entry in "vulnerabilities/", users are free to
make their own assessment of their exposure.
== Microcode Revision Discussion ==
The microcode versions in the table were generated from the Intel
microcode git repo:
8ac9378a8487 ("microcode-20241112 Release")
which as of this writing lags behind the latest microcode-20250211.
It can be argued that the versions that the kernel picks to call "old"
should be a revision or two old. Which specific version is picked is
less important to me than picking *a* version and enforcing it.
This repository contains only microcode versions that Intel has deemed
to be OS-loadable. It is quite possible that the BIOS has loaded a
newer microcode than the latest in this repo. If this happens, the
system is considered to have new microcode, not old.
Specifically, the sysfs file and taint flag answer the question:
Is the CPU running on the latest OS-loadable microcode,
or something even later that the BIOS loaded?
In other words, Intel never publishes an authoritative list of CPUs
and latest microcode revisions. Until it does, this is the best that
Linux can do.
Also note that the "intel-ucode-defs.h" file is simple, ugly and
has lots of magic numbers. That's on purpose and should allow a
single file to be shared across lots of stable kernel regardless of if
they have the new "VFM" infrastructure or not. It was generated with
a dumb script.
== FAQ ==
Q: Does this tell me if my system is secure or insecure?
A: No. It only tells you if your microcode was old when the
system booted.
Q: Should the kernel warn if the microcode list itself is too old?
A: No. New kernels will get new microcode lists, both mainline
and stable. The only way to have an old list is to be running
an old kernel in which case you have bigger problems.
Q: Is this for security or functional issues?
A: Both.
Q: If a given microcode update only has functional problems but
no security issues, will it be considered old?
A: Yes. All microcode image versions within a microcode release
are treated identically. Intel appears to make security
updates without disclosing them in the release notes. Thus,
all updates are considered to be security-relevant.
Q: Who runs old microcode?
A: Anybody with an old distro. This happens all the time inside
of Intel where there are lots of weird systems in labs that
might not be getting regular distro updates and might also
be running rather exotic microcode images.
Q: If I update my microcode after booting will it stop saying
"Vulnerable"?
A: No. Just like all the other vulnerabilies, you need to
reboot before the kernel will reassess your vulnerability.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: "Ahmed S. Darwish" <darwi@linutronix.de>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/all/20250421195659.CF426C07%40davehans-spike.ostc.intel.com
(cherry picked from commit 9127865b15eb0a1bd05ad7efe29489c44394bdc1)
Document the lifetime, nolifetime and max_open_zones mount options
added for zoned rt file systems.
Also add documentation describing the max_open_zones sysfs attribute
exposed in /sys/fs/xfs/<dev>/zoned/
Fixes: 4e4d520755 ("xfs: add the zoned space allocator")
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Presently we start garbage collection late - when we start running
out of free zones to backfill max_open_zones. This is a reasonable
default as it minimizes write amplification. The longer we wait,
the more blocks are invalidated and reclaim cost less in terms
of blocks to relocate.
Starting this late however introduces a risk of GC being outcompeted
by user writes. If GC can't keep up, user writes will be forced to
wait for free zones with high tail latencies as a result.
This is not a problem under normal circumstances, but if fragmentation
is bad and user write pressure is high (multiple full-throttle
writers) we will "bottom out" of free zones.
To mitigate this, introduce a zonegc_low_space tunable that lets the
user specify a percentage of how much of the unused space that GC
should keep available for writing. A high value will reclaim more of
the space occupied by unused blocks, creating a larger buffer against
write bursts.
This comes at a cost as write amplification is increased. To
illustrate this using a sample workload, setting zonegc_low_space to
60% avoids high (500ms) max latencies while increasing write
amplification by 15%.
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
DCCP was orphaned in 2021 by commit 054c4610bd ("MAINTAINERS: dccp:
move Gerrit Renker to CREDITS"), which noted that the last maintainer
had been inactive for five years.
In recent years, it has become a playground for syzbot, and most changes
to DCCP have been odd bug fixes triggered by syzbot. Apart from that,
the only changes have been driven by treewide or networking API updates
or adjustments related to TCP.
Thus, in 2023, we announced we would remove DCCP in 2025 via commit
b144fcaf46 ("dccp: Print deprecation notice.").
Since then, only one individual has contacted the netdev mailing list. [0]
There is ongoing research for Multipath DCCP. The repository is hosted
on GitHub [1], and development is not taking place through the upstream
community. While the repository is published under the GPLv2 license,
the scheduling part remains proprietary, with a LICENSE file [2] stating:
"This is not Open Source software."
The researcher mentioned a plan to address the licensing issue, upstream
the patches, and step up as a maintainer, but there has been no further
communication since then.
Maintaining DCCP for a decade without any real users has become a burden.
Therefore, it's time to remove it.
Removing DCCP will also provide significant benefits to TCP. It allows
us to freely reorganize the layout of struct inet_connection_sock, which
is currently shared with DCCP, and optimize it to reduce the number of
cachelines accessed in the TCP fast path.
Note that we keep DCCP netfilter modules as requested. [3]
Link: https://lore.kernel.org/netdev/20230710182253.81446-1-kuniyu@amazon.com/T/#u #[0]
Link: https://github.com/telekom/mp-dccp #[1]
Link: https://github.com/telekom/mp-dccp/blob/mpdccp_v03_k5.10/net/dccp/non_gpl_scheduler/LICENSE #[2]
Link: https://lore.kernel.org/netdev/Z_VQ0KlCRkqYWXa-@calendula/ #[3]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paul Moore <paul@paul-moore.com> (LSM and SELinux)
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Link: https://patch.msgid.link/20250410023921.11307-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
First of all, using 'mmio' prevents proper implementation of 8-bit accessors.
Second, it's simply inconsistent with uart8250 set of options. Rename it to
'mmio32'. While at it, remove rather misleading comment in the documentation.
From now on mmio32 is self-explanatory and pciserial supports not only 32-bit
MMIO accessors.
Also, while at it, fix the comment for the "pciserial" case. The comment
seems to be a copy'n'paste error when mentioning "serial" instead of
"pciserial" (with double quotes). Fix this.
With that, move it upper, so we don't calculate 'buf' twice.
Fixes: 3181424aea ("x86/early_printk: Add support for MMIO-based UARTs")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Denis Mukhin <dmukhin@ford.com>
Link: https://lore.kernel.org/r/20250407172214.792745-1-andriy.shevchenko@linux.intel.com
Pull more s390 updates from Vasily Gorbik:
- Fix machine check handler _CIF_MCCK_GUEST bit setting by adding the
missing base register for relocated lowcore address
- Fix build failure on older linkers by conditionally adding the
-no-pie linker option only when it is supported
- Fix inaccurate kernel messages in vfio-ap by providing descriptive
error notifications for AP queue sharing violations
- Fix PCI isolation logic by ensuring non-VF devices correctly return
false in zpci_bus_is_isolated_vf()
- Fix PCI DMA range map setup by using dma_direct_set_offset() to add a
proper sentinel element, preventing potential overruns and
translation errors
- Cleanup header dependency problems with asm-offsets.c
- Add fault info for unexpected low-address protection faults in user
mode
- Add support for HOTPLUG_SMT, replacing the arch-specific "nosmt"
handling with common code handling
- Use bitop functions to implement CPU flag helper functions to ensure
that bits cannot get lost if modified in different contexts on a CPU
- Remove unused machine_flags for the lowcore
* tag 's390-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/vfio-ap: Fix no AP queue sharing allowed message written to kernel log
s390/pci: Fix dev.dma_range_map missing sentinel element
s390/mm: Dump fault info in case of low address protection fault
s390/smp: Add support for HOTPLUG_SMT
s390: Fix linker error when -no-pie option is unavailable
s390/processor: Use bitop functions for cpu flag helper functions
s390/asm-offsets: Remove ASM_OFFSETS_C
s390/asm-offsets: Include ftrace_regs.h instead of ftrace.h
s390/kvm: Split kvm_host header file
s390/pci: Fix zpci_bus_is_isolated_vf() for non-VFs
s390/lowcore: Remove unused machine_flags
s390/entry: Fix setting _CIF_MCCK_GUEST with lowcore relocation
Pull RISC-V updates from Palmer Dabbelt:
- The sub-architecture selection Kconfig system has been cleaned up,
the documentation has been improved, and various detections have been
fixed
- The vector-related extensions dependencies are now validated when
parsing from device tree and in the DT bindings
- Misaligned access probing can be overridden via a kernel command-line
parameter, along with various fixes to misalign access handling
- Support for relocatable !MMU kernels builds
- Support for hpge pfnmaps, which should improve TLB utilization
- Support for runtime constants, which improves the d_hash()
performance
- Support for bfloat16, Zicbom, Zaamo, Zalrsc, Zicntr, Zihpm
- Various fixes, including:
- We were missing a secondary mmu notifier call when flushing the
tlb which is required for IOMMU
- Fix ftrace panics by saving the registers as expected by ftrace
- Fix a couple of stimecmp usage related to cpu hotplug
- purgatory_start is now aligned as per the STVEC requirements
- A fix for hugetlb when calculating the size of non-present PTEs
* tag 'riscv-for-linus-6.15-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (65 commits)
riscv: Add norvc after .option arch in runtime const
riscv: Make sure toolchain supports zba before using zba instructions
riscv/purgatory: 4B align purgatory_start
riscv/kexec_file: Handle R_RISCV_64 in purgatory relocator
selftests: riscv: fix v_exec_initval_nolibc.c
riscv: Fix hugetlb retrieval of number of ptes in case of !present pte
riscv: print hartid on bringup
riscv: Add norvc after .option arch in runtime const
riscv: Remove CONFIG_PAGE_OFFSET
riscv: Support CONFIG_RELOCATABLE on riscv32
asm-generic: Always define Elf_Rel and Elf_Rela
riscv: Support CONFIG_RELOCATABLE on NOMMU
riscv: Allow NOMMU kernels to access all of RAM
riscv: Remove duplicate CONFIG_PAGE_OFFSET definition
RISC-V: errata: Use medany for relocatable builds
dt-bindings: riscv: document vector crypto requirements
dt-bindings: riscv: add vector sub-extension dependencies
dt-bindings: riscv: d requires f
RISC-V: add f & d extension validation checks
RISC-V: add vector crypto extension validation checks
...
Pull ring-buffer updates from Steven Rostedt:
"Persistent buffer cleanups and simplifications.
It was mistaken that the physical memory returned from "reserve_mem"
had to be vmap()'d to get to it from a virtual address. But
reserve_mem already maps the memory to the virtual address of the
kernel so a simple phys_to_virt() can be used to get to the virtual
address from the physical memory returned by "reserve_mem". With this
new found knowledge, the code can be cleaned up and simplified.
- Enforce that the persistent memory is page aligned
As the buffers using the persistent memory are all going to be
mapped via pages, make sure that the memory given to the tracing
infrastructure is page aligned. If it is not, it will print a
warning and fail to map the buffer.
- Use phys_to_virt() to get the virtual address from reserve_mem
Instead of calling vmap() on the physical memory returned from
"reserve_mem", use phys_to_virt() instead.
As the memory returned by "memmap" or any other means where a
physical address is given to the tracing infrastructure, it still
needs to be vmap(). Since this memory can never be returned back to
the buddy allocator nor should it ever be memmory mapped to user
space, flag this buffer and up the ref count. The ref count will
keep it from ever being freed, and the flag will prevent it from
ever being memory mapped to user space.
- Use vmap_page_range() for memmap virtual address mapping
For the memmap buffer, instead of allocating an array of struct
pages, assigning them to the contiguous phsycial memory and then
passing that to vmap(), use vmap_page_range() instead
- Replace flush_dcache_folio() with flush_kernel_vmap_range()
Instead of calling virt_to_folio() and passing that to
flush_dcache_folio(), just call flush_kernel_vmap_range() directly.
This also fixes a bug where if a subbuffer was bigger than
PAGE_SIZE only the PAGE_SIZE portion would be flushed"
* tag 'trace-ringbuffer-v6.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Use flush_kernel_vmap_range() over flush_dcache_folio()
tracing: Use vmap_page_range() to map memmap ring buffer
tracing: Have reserve_mem use phys_to_virt() and separate from memmap buffer
tracing: Enforce the persistent ring buffer to be page aligned
Pull fuse updates from Miklos Szeredi:
- Allow connection to server to time out (Joanne Koong)
- If server doesn't support creating a hard link, return EPERM rather
than ENOSYS (Matt Johnston)
- Allow file names longer than 1024 chars (Bernd Schubert)
- Fix a possible race if request on io_uring queue is interrupted
(Bernd Schubert)
- Misc fixes and cleanups
* tag 'fuse-update-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: remove unneeded atomic set in uring creation
fuse: fix uring race condition for null dereference of fc
fuse: Increase FUSE_NAME_MAX to PATH_MAX
fuse: Allocate only namelen buf memory in fuse_notify_
fuse: add default_request_timeout and max_request_timeout sysctls
fuse: add kernel-enforced timeout option for requests
fuse: optmize missing FUSE_LINK support
fuse: Return EPERM rather than ENOSYS from link()
fuse: removed unused function fuse_uring_create() from header
fuse: {io-uring} Fix a possible req cancellation race
Pull non-MM updates from Andrew Morton:
- The series "powerpc/crash: use generic crashkernel reservation" from
Sourabh Jain changes powerpc's kexec code to use more of the generic
layers.
- The series "get_maintainer: report subsystem status separately" from
Vlastimil Babka makes some long-requested improvements to the
get_maintainer output.
- The series "ucount: Simplify refcounting with rcuref_t" from
Sebastian Siewior cleans up and optimizing the refcounting in the
ucount code.
- The series "reboot: support runtime configuration of emergency
hw_protection action" from Ahmad Fatoum improves the ability for a
driver to perform an emergency system shutdown or reboot.
- The series "Converge on using secs_to_jiffies() part two" from Easwar
Hariharan performs further migrations from msecs_to_jiffies() to
secs_to_jiffies().
- The series "lib/interval_tree: add some test cases and cleanup" from
Wei Yang permits more userspace testing of kernel library code, adds
some more tests and performs some cleanups.
- The series "hung_task: Dump the blocking task stacktrace" from Masami
Hiramatsu arranges for the hung_task detector to dump the stack of
the blocking task and not just that of the blocked task.
- The series "resource: Split and use DEFINE_RES*() macros" from Andy
Shevchenko provides some cleanups to the resource definition macros.
- Plus the usual shower of singleton patches - please see the
individual changelogs for details.
* tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
mailmap: consolidate email addresses of Alexander Sverdlin
fs/procfs: fix the comment above proc_pid_wchan()
relay: use kasprintf() instead of fixed buffer formatting
resource: replace open coded variant of DEFINE_RES()
resource: replace open coded variants of DEFINE_RES_*_NAMED()
resource: replace open coded variant of DEFINE_RES_NAMED_DESC()
resource: split DEFINE_RES_NAMED_DESC() out of DEFINE_RES_NAMED()
samples: add hung_task detector mutex blocking sample
hung_task: show the blocker task if the task is hung on mutex
kexec_core: accept unaccepted kexec segments' destination addresses
watchdog/perf: optimize bytes copied and remove manual NUL-termination
lib/interval_tree: fix the comment of interval_tree_span_iter_next_gap()
lib/interval_tree: skip the check before go to the right subtree
lib/interval_tree: add test case for span iteration
lib/interval_tree: add test case for interval_tree_iter_xxx() helpers
lib/rbtree: add random seed
lib/rbtree: split tests
lib/rbtree: enable userland test suite for rbtree related data structure
checkpatch: describe --min-conf-desc-length
scripts/gdb/symbols: determine KASLR offset on s390
...
Pull MM updates from Andrew Morton:
- The series "Enable strict percpu address space checks" from Uros
Bizjak uses x86 named address space qualifiers to provide
compile-time checking of percpu area accesses.
This has caused a small amount of fallout - two or three issues were
reported. In all cases the calling code was found to be incorrect.
- The series "Some cleanup for memcg" from Chen Ridong implements some
relatively monir cleanups for the memcontrol code.
- The series "mm: fixes for device-exclusive entries (hmm)" from David
Hildenbrand fixes a boatload of issues which David found then using
device-exclusive PTE entries when THP is enabled. More work is
needed, but this makes thins better - our own HMM selftests now
succeed.
- The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed
remove the z3fold and zbud implementations. They have been deprecated
for half a year and nobody has complained.
- The series "mm: further simplify VMA merge operation" from Lorenzo
Stoakes implements numerous simplifications in this area. No runtime
effects are anticipated.
- The series "mm/madvise: remove redundant mmap_lock operations from
process_madvise()" from SeongJae Park rationalizes the locking in the
madvise() implementation. Performance gains of 20-25% were observed
in one MADV_DONTNEED microbenchmark.
- The series "Tiny cleanup and improvements about SWAP code" from
Baoquan He contains a number of touchups to issues which Baoquan
noticed when working on the swap code.
- The series "mm: kmemleak: Usability improvements" from Catalin
Marinas implements a couple of improvements to the kmemleak
user-visible output.
- The series "mm/damon/paddr: fix large folios access and schemes
handling" from Usama Arif provides a couple of fixes for DAMON's
handling of large folios.
- The series "mm/damon/core: fix wrong and/or useless damos_walk()
behaviors" from SeongJae Park fixes a few issues with the accuracy of
kdamond's walking of DAMON regions.
- The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo
Stoakes changes the interaction between framebuffer deferred-io and
core MM. No functional changes are anticipated - this is preparatory
work for the future removal of page structure fields.
- The series "mm/damon: add support for hugepage_size DAMOS filter"
from Usama Arif adds a DAMOS filter which permits the filtering by
huge page sizes.
- The series "mm: permit guard regions for file-backed/shmem mappings"
from Lorenzo Stoakes extends the guard region feature from its
present "anon mappings only" state. The feature now covers shmem and
file-backed mappings.
- The series "mm: batched unmap lazyfree large folios during
reclamation" from Barry Song cleans up and speeds up the unmapping
for pte-mapped large folios.
- The series "reimplement per-vma lock as a refcount" from Suren
Baghdasaryan puts the vm_lock back into the vma. Our reasons for
pulling it out were largely bogus and that change made the code more
messy. This patchset provides small (0-10%) improvements on one
microbenchmark.
- The series "Docs/mm/damon: misc DAMOS filters documentation fixes and
improves" from SeongJae Park does some maintenance work on the DAMON
docs.
- The series "hugetlb/CMA improvements for large systems" from Frank
van der Linden addresses a pile of issues which have been observed
when using CMA on large machines.
- The series "mm/damon: introduce DAMOS filter type for unmapped pages"
from SeongJae Park enables users of DMAON/DAMOS to filter my the
page's mapped/unmapped status.
- The series "zsmalloc/zram: there be preemption" from Sergey
Senozhatsky teaches zram to run its compression and decompression
operations preemptibly.
- The series "selftests/mm: Some cleanups from trying to run them" from
Brendan Jackman fixes a pile of unrelated issues which Brendan
encountered while runnimg our selftests.
- The series "fs/proc/task_mmu: add guard region bit to pagemap" from
Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to
determine whether a particular page is a guard page.
- The series "mm, swap: remove swap slot cache" from Kairui Song
removes the swap slot cache from the allocation path - it simply
wasn't being effective.
- The series "mm: cleanups for device-exclusive entries (hmm)" from
David Hildenbrand implements a number of unrelated cleanups in this
code.
- The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual
implements a number of preparatoty cleanups to the GENERIC_PTDUMP
Kconfig logic.
- The series "mm/damon: auto-tune aggregation interval" from SeongJae
Park implements a feedback-driven automatic tuning feature for
DAMON's aggregation interval tuning.
- The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in
powerpc, sparc and x86 lazy MMU implementations. Ryan did this in
preparation for implementing lazy mmu mode for arm64 to optimize
vmalloc.
- The series "mm/page_alloc: Some clarifications for migratetype
fallback" from Brendan Jackman reworks some commentary to make the
code easier to follow.
- The series "page_counter cleanup and size reduction" from Shakeel
Butt cleans up the page_counter code and fixes a size increase which
we accidentally added late last year.
- The series "Add a command line option that enables control of how
many threads should be used to allocate huge pages" from Thomas
Prescher does that. It allows the careful operator to significantly
reduce boot time by tuning the parallalization of huge page
initialization.
- The series "Fix calculations in trace_balance_dirty_pages() for cgwb"
from Tang Yizhou fixes the tracing output from the dirty page
balancing code.
- The series "mm/damon: make allow filters after reject filters useful
and intuitive" from SeongJae Park improves the handling of allow and
reject filters. Behaviour is made more consistent and the documention
is updated accordingly.
- The series "Switch zswap to object read/write APIs" from Yosry Ahmed
updates zswap to the new object read/write APIs and thus permits the
removal of some legacy code from zpool and zsmalloc.
- The series "Some trivial cleanups for shmem" from Baolin Wang does as
it claims.
- The series "fs/dax: Fix ZONE_DEVICE page reference counts" from
Alistair Popple regularizes the weird ZONE_DEVICE page refcount
handling in DAX, permittig the removal of a number of special-case
checks.
- The series "refactor mremap and fix bug" from Lorenzo Stoakes is a
preparatoty refactoring and cleanup of the mremap() code.
- The series "mm: MM owner tracking for large folios (!hugetlb) +
CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in
which we determine whether a large folio is known to be mapped
exclusively into a single MM.
- The series "mm/damon: add sysfs dirs for managing DAMOS filters based
on handling layers" from SeongJae Park adds a couple of new sysfs
directories to ease the management of DAMON/DAMOS filters.
- The series "arch, mm: reduce code duplication in mem_init()" from
Mike Rapoport consolidates many per-arch implementations of
mem_init() into code generic code, where that is practical.
- The series "mm/damon/sysfs: commit parameters online via
damon_call()" from SeongJae Park continues the cleaning up of sysfs
access to DAMON internal data.
- The series "mm: page_ext: Introduce new iteration API" from Luiz
Capitulino reworks the page_ext initialization to fix a boot-time
crash which was observed with an unusual combination of compile and
cmdline options.
- The series "Buddy allocator like (or non-uniform) folio split" from
Zi Yan reworks the code to split a folio into smaller folios. The
main benefit is lessened memory consumption: fewer post-split folios
are generated.
- The series "Minimize xa_node allocation during xarry split" from Zi
Yan reduces the number of xarray xa_nodes which are generated during
an xarray split.
- The series "drivers/base/memory: Two cleanups" from Gavin Shan
performs some maintenance work on the drivers/base/memory code.
- The series "Add tracepoints for lowmem reserves, watermarks and
totalreserve_pages" from Martin Liu adds some more tracepoints to the
page allocator code.
- The series "mm/madvise: cleanup requests validations and
classifications" from SeongJae Park cleans up some warts which
SeongJae observed during his earlier madvise work.
- The series "mm/hwpoison: Fix regressions in memory failure handling"
from Shuai Xue addresses two quite serious regressions which Shuai
has observed in the memory-failure implementation.
- The series "mm: reliable huge page allocator" from Johannes Weiner
makes huge page allocations cheaper and more reliable by reducing
fragmentation.
- The series "Minor memcg cleanups & prep for memdescs" from Matthew
Wilcox is preparatory work for the future implementation of memdescs.
- The series "track memory used by balloon drivers" from Nico Pache
introduces a way to track memory used by our various balloon drivers.
- The series "mm/damon: introduce DAMOS filter type for active pages"
from Nhat Pham permits users to filter for active/inactive pages,
separately for file and anon pages.
- The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia
separates the proactive reclaim statistics from the direct reclaim
statistics.
- The series "mm/vmscan: don't try to reclaim hwpoison folio" from
Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim
code.
* tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits)
mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex()
x86/mm: restore early initialization of high_memory for 32-bits
mm/vmscan: don't try to reclaim hwpoison folio
mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper
cgroup: docs: add pswpin and pswpout items in cgroup v2 doc
mm: vmscan: split proactive reclaim statistics from direct reclaim statistics
selftests/mm: speed up split_huge_page_test
selftests/mm: uffd-unit-tests support for hugepages > 2M
docs/mm/damon/design: document active DAMOS filter type
mm/damon: implement a new DAMOS filter type for active pages
fs/dax: don't disassociate zero page entries
MM documentation: add "Unaccepted" meminfo entry
selftests/mm: add commentary about 9pfs bugs
fork: use __vmalloc_node() for stack allocation
docs/mm: Physical Memory: Populate the "Zones" section
xen: balloon: update the NR_BALLOON_PAGES state
hv_balloon: update the NR_BALLOON_PAGES state
balloon_compaction: update the NR_BALLOON_PAGES state
meminfo: add a per node counter for balloon drivers
mm: remove references to folio in __memcg_kmem_uncharge_page()
...
Introduce two new sysctls, "default_request_timeout" and
"max_request_timeout". These control how long (in seconds) a server can
take to reply to a request. If the server does not reply by the timeout,
then the connection will be aborted. The upper bound on these sysctl
values is 65535.
"default_request_timeout" sets the default timeout if no timeout is
specified by the fuse server on mount. 0 (default) indicates no default
timeout should be enforced. If the server did specify a timeout, then
default_request_timeout will be ignored.
"max_request_timeout" sets the max amount of time the server may take to
reply to a request. 0 (default) indicates no maximum timeout. If
max_request_timeout is set and the fuse server attempts to set a
timeout greater than max_request_timeout, the system will use
max_request_timeout as the timeout. Similarly, if default_request_timeout
is greater than max_request_timeout, the system will use
max_request_timeout as the timeout. If the server does not request a
timeout and default_request_timeout is set to 0 but max_request_timeout
is set, then the timeout will be max_request_timeout.
Please note that these timeouts are not 100% precise. The request may
take roughly an extra FUSE_TIMEOUT_TIMER_FREQ seconds beyond the set max
timeout due to how it's internally implemented.
$ sysctl -a | grep fuse.default_request_timeout
fs.fuse.default_request_timeout = 0
$ echo 65536 | sudo tee /proc/sys/fs/fuse/default_request_timeout
tee: /proc/sys/fs/fuse/default_request_timeout: Invalid argument
$ echo 65535 | sudo tee /proc/sys/fs/fuse/default_request_timeout
65535
$ sysctl -a | grep fuse.default_request_timeout
fs.fuse.default_request_timeout = 65535
$ echo 0 | sudo tee /proc/sys/fs/fuse/default_request_timeout
0
$ sysctl -a | grep fuse.default_request_timeout
fs.fuse.default_request_timeout = 0
[Luis Henriques: Limit the timeout to the range [FUSE_TIMEOUT_TIMER_FREQ,
fuse_max_req_timeout]]
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Luis Henriques <luis@igalia.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
