| Age | Commit message (Collapse) | Author |
|---|
|
Adds the support for HiSilicon NoC (Network on Chip) PMU which
will be used to monitor the events on the system bus. The PMU
device will be named after the SCL ID (either Super CPU cluster
or Super IO cluster) and the index ID, just similar to other
HiSilicon Uncore PMUs. Below PMU formats are provided besides
the event:
- ch: the transaction channel (data, request, response, etc) which
can be used to filter the counting.
- tt_en: tracetag filtering enable. Just as other HiSilicon Uncore
PMUs the NoC PMU supports only counting the transactions with
tracetag.
The NoC PMU doesn't have an interrupt to indicate the overflow.
However we have a 64 bit counter which is large enough and it's
nearly impossible to overflow.
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
While Designware PCIe PMU allows to count only one time based event
at a time, it allows to count all the lane events simultaneously.
After the patch one is able to count a group of lane events:
$ perf stat -e '{dwc_rootport/tx_memory_write,lane=1/,dwc_rootport/rx_memory_read,lane=0/}' dd if=/dev/nvme0n1 of=/dev/null bs=1M count=1
Earlier the events wouldn't have been counted successfully.
Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
As per admin guide documentation, "rodata=on" should be the default on
platforms. Documentation/admin-guide/kernel-parameters.txt describes
these options as
rodata= [KNL,EARLY]
on Mark read-only kernel memory as read-only (default).
off Leave read-only kernel memory writable for debugging.
full Mark read-only kernel memory and aliases as read-only
[arm64]
But on arm64 platform, RODATA_FULL_DEFAULT_ENABLED is enabled by default,
so "rodata=full" is the default instead.
For parity with other architectures, namely x86, rework 'rodata=on' to
match the current "full" behaviour and replace 'rodata=full' with a new
'rodata=noalias' option which retains writable aliases in the direct map
for memory regions outside of the kernel image.
Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
|
|
Commit 21d59d00221e4e ("xfs: remove deprecated sysctl knobs") moves
recently-removed sysctls to the removed sysctls table but fails to
extend the table, hence triggering Sphinx warning:
Documentation/admin-guide/xfs.rst:365: ERROR: Malformed table.
Text in column margin in table line 8.
============================= =======
Name Removed
============================= =======
fs.xfs.xfsbufd_centisec v4.0
fs.xfs.age_buffer_centisecs v4.0
fs.xfs.irix_symlink_mode v6.18
fs.xfs.irix_sgid_inherit v6.18
fs.xfs.speculative_cow_prealloc_lifetime v6.18
============================= ======= [docutils]
Extend "Name" column of the table to fit the now-longest sysctl, which
is fs.xfs.speculative_cow_prealloc_lifetime.
Fixes: 21d59d00221e ("xfs: remove deprecated sysctl knobs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/linux-next/20250908180406.32124fb7@canb.auug.org.au/
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
|
|
Ciphertext hiding prevents host accesses from reading the ciphertext of
SNP guest private memory. Instead of reading ciphertext, the host reads
will see constant default values (0xff).
The SEV ASID space is split into SEV and SEV-ES/SEV-SNP ASID ranges.
Enabling ciphertext hiding further splits the SEV-ES/SEV-SNP ASID space
into separate ASID ranges for SEV-ES and SEV-SNP guests.
Add a new off-by-default kvm-amd module parameter to enable ciphertext
hiding and allow the admin to configure the SEV-ES and SEV-SNP ASID
ranges. Simply cap the maximum SEV-SNP ASID as appropriate, i.e. don't
reject loading KVM or disable ciphertest hiding for a too-big value, as
KVM's general approach for module params is to sanitize inputs based on
hardware/kernel support, not burn the world down. This also allows the
admin to use -1u to assign all SEV-ES/SNP ASIDs to SNP without needing
dedicated handling in KVM.
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/95abc49edfde36d4fb791570ea2a4be6ad95fd0d.1755721927.git.ashish.kalra@amd.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
|
|
Add a kernel command-line parameter to enable or disable the exposure of
the ABMC (Assignable Bandwidth Monitoring Counters) hardware feature to
resctrl.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
|
|
User reported current document about SYS_INFO_PANIC_CONSOLE_REPLAY is
confusing, that people could expect all user space console messages to be
replayed.
Specify that only 'kernel' messages will be replayed to solve the confusion.
Link: https://lkml.kernel.org/r/20250825025701.81921-3-feng.tang@linux.alibaba.com
Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com>
Reported-by: Askar Safin <safinaskar@zohomail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Document addr_unit DAMON sysfs file on DAMON usage document.
Link: https://lkml.kernel.org/r/20250828171242.59810-10-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ze zuo <zuoze1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
This includes the PR_SET_THP_DISABLE/PR_GET_THP_DISABLE pair of prctl
calls as well the newly introduced PR_THP_DISABLE_EXCEPT_ADVISED flag for
the PR_SET_THP_DISABLE prctl call.
Link: https://lkml.kernel.org/r/20250815135549.130506-5-usamaarif642@gmail.com
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yafang <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
|
Use attack vector controls to select whether VMSCAPE requires mitigation,
similar to other bugs.
Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
|
|
Cross-merge networking fixes after downstream PR (net-6.17-rc6).
Conflicts:
net/netfilter/nft_set_pipapo.c
net/netfilter/nft_set_pipapo_avx2.c
c4eaca2e1052 ("netfilter: nft_set_pipapo: don't check genbit from packetpath lookups")
84c1da7b38d9 ("netfilter: nft_set_pipapo: use avx2 algorithm for insertions too")
Only trivial adjacent changes (in a doc and a Makefile).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull vmescape mitigation fixes from Dave Hansen:
"Mitigate vmscape issue with indirect branch predictor flushes.
vmscape is a vulnerability that essentially takes Spectre-v2 and
attacks host userspace from a guest. It particularly affects
hypervisors like QEMU.
Even if a hypervisor may not have any sensitive data like disk
encryption keys, guest-userspace may be able to attack the
guest-kernel using the hypervisor as a confused deputy.
There are many ways to mitigate vmscape using the existing Spectre-v2
defenses like IBRS variants or the IBPB flushes. This series focuses
solely on IBPB because it works universally across vendors and all
vulnerable processors. Further work doing vendor and model-specific
optimizations can build on top of this if needed / wanted.
Do the normal issue mitigation dance:
- Add the CPU bug boilerplate
- Add a list of vulnerable CPUs
- Use IBPB to flush the branch predictors after running guests"
* tag 'vmscape-for-linus-20250904' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vmscape: Add old Intel CPUs to affected list
x86/vmscape: Warn when STIBP is disabled with SMT
x86/bugs: Move cpu_bugs_smt_update() down
x86/vmscape: Enable the mitigation
x86/vmscape: Add conditional IBPB mitigation
x86/vmscape: Enumerate VMSCAPE bug
Documentation/hw-vuln: Add VMSCAPE documentation
|
|
The ov6650 driver was introduced in v2.6.37 to support the OMAP1-based
Amstrad Delta video phone. The platform still has a board file in the
kernel, but support for the camera was dropped in commit ce548396a433
("media: mach-omap1: board-ams-delta.c: remove soc_camera dependencies")
in v5.9. The driver has been unused since as it has received neither
ACPI nor DT support.
The ov6650 driver is one of the last sensor drivers calling
clk_set_rate(). This is deprecated, and calls to the function are being
removed to avoid cargo-cult. As the driver is unlikely to ever be used
again, drop it instead of trying to avoid call clk_set_rate().
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mehdi Djait <mehdi.djait@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
|
|
Replace hverkuil@xs4all.nl by hverkuil@kernel.org.
Signed-off-by: Hans Verkuil <hverkuil@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
|
|
Redundant data is used to enhance data fault tolerance, and the storage
method for redundant data vary depending on the RAID levels. And it's
important to maintain the consistency of redundant data.
Bitmap is used to record which data blocks have been synchronized and which
ones need to be resynchronized or recovered. Each bit in the bitmap
represents a segment of data in the array. When a bit is set, it indicates
that the multiple redundant copies of that data segment may not be
consistent. Data synchronization can be performed based on the bitmap after
power failure or readding a disk. If there is no bitmap, a full disk
synchronization is required.
Due to known performance issues with md-bitmap and the unreasonable
implementations:
- self-managed IO submitting like filemap_write_page();
- global spin_lock
I have decided not to continue optimizing based on the current bitmap
implementation, this new bitmap is invented without locking from IO fast
path and can be used with fast disks.
For designs and details, see the comments in drivers/md-llbitmap.c.
Link: https://lore.kernel.org/linux-raid/20250829080426.1441678-12-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Li Nan <linan122@huawei.com>
|
|
Currently bitmap_ops is registered while allocating mddev, this is fine
when there is only one bitmap_ops.
Delay setting bitmap_ops until creating bitmap, so that user can choose
which bitmap to use before running the array.
Link: https://lore.kernel.org/linux-raid/20250721171557.34587-7-yukuai@kernel.org
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Li Nan <linan122@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
|
|
The api will be used by mdadm to set bitmap_type while creating new array
or assembling array, prepare to add a new bitmap.
Currently available options are:
cat /sys/block/md0/md/bitmap_type
none [bitmap]
Link: https://lore.kernel.org/linux-raid/20250829080426.1441678-6-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Xiao Ni <xni@redhat.com>
Reviewed-by: Li Nan <linan122@huawei.com>
|
|
Pull for-6.17-fixes to receive 79f919a89c9d ("cgroup: split
cgroup_destroy_wq into 3 workqueues") to resolve its conflict with
7fa33aa3b001 ("cgroup: WQ_PERCPU added to alloc_workqueue users"). The
latter adds WQ_PERCPU when creating cgroup_destroy_wq and the former splits
the workqueue into three. Resolve by applying WQ_PERCPU to the three split
workqueues.
Signed-off-by: Tejun Heo <tj@kernel.org>
|
|
These sysctl knobs were scheduled for removal in September 2025. That
time has come, so remove them.
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
|
|
These four mount options were scheduled for removal in September 2025,
so remove them now.
Cc: preichl@redhat.com
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
|
|
We promised to turn off these old features by default in September 2025.
Do so now.
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
|
|
Cross-merge networking fixes after downstream PR (net-6.17-rc5).
No conflicts.
Adjacent changes:
include/net/sock.h
c51613fa276f ("net: add sk->sk_drop_counters")
5d6b58c932ec ("net: lockless sock_i_ino()")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Add "debug" option for "cfi=" bootparam to get details on early CFI
initialization steps so future Kees can find breakage easier.
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250904034656.3670313-5-kees@kernel.org
|
|
The kernel-parameters.txt didn't have a section for the cfi= options.
Add it.
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250904034656.3670313-3-kees@kernel.org
|
|
Instead of adding ad-hoc debugging glue to the microcode loader each
time I need it, add debugging functionality which is not built by
default.
Simulate all patch handling the loader does except the actual loading of
the microcode patch into the hardware.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250820135043.19048-3-bp@kernel.org
|
|
Add a "microcode=" command line argument after which all options can be
passed in a comma-separated list.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Reviewed-by: Chang S. Bae <chang.seok.bae@intel.com>
Link: https://lore.kernel.org/20250820135043.19048-2-bp@kernel.org
|
|
There is an obvious mistake in nfsroot.rst where pxelinux was wrongly
written as pxeliunx. Fix it.
Signed-off-by: Zenghui Yu <zenghui.yu@linux.dev>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250827144738.43361-1-zenghui.yu@linux.dev
|
|
Introduce a mechanism to detect and warn about prolonged interrupt handlers.
With a new command-line parameter (irqhandler.duration_warn_us=), users can
configure the duration threshold in microseconds when a warning in such
format should be emitted:
"[CPU14] long duration of IRQ[159:bad_irq_handler [long_irq]], took: 1330 us"
The implementation uses local_clock() to measure the execution duration of the
generic IRQ per-CPU event handler.
Signed-off-by: Wladislav Wiebe <wladislav.wiebe@nokia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/all/20250804093525.851-1-wladislav.wiebe@nokia.com
|
|
Changed "write-throuth" to "write-through".
Signed-off-by: Vivek Alurkar <primalkenja@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250821051622.8341-2-primalkenja@gmail.com
|
|
Cross-merge networking fixes after downstream PR (net-6.17-rc4).
No conflicts.
Adjacent changes:
drivers/net/ethernet/intel/idpf/idpf_txrx.c
02614eee26fb ("idpf: do not linearize big TSO packets")
6c4e68480238 ("idpf: remove obsolete stashing code")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Attack vector controls for SSB were missed in the initial attack vector series.
The default mitigation for SSB requires user-space opt-in so it is only
relevant for user->user attacks. Check with attack vector controls when
the command is auto - i.e., no explicit user selection has been done.
Fixes: 2d31d2874663 ("x86/bugs: Define attack vectors relevant for each bug")
Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250819192200.2003074-5-david.kaplan@amd.com
|
|
This patch introduces dm-pcache, a new DM target that places a DAX-
capable persistent-memory device in front of any slower block device and
uses it as a high-throughput, low-latency cache.
Design highlights
-----------------
- DAX data path – data is copied directly between DRAM and the pmem
mapping, bypassing the block layer’s overhead.
- Segmented, crash-consistent layout
- all layout metadata are dual-replicated CRC-protected.
- atomic kset flushes; key replay on mount guarantees cache integrity
even after power loss.
- Striped multi-tree index
- Multi‑tree indexing for high parallelism.
- overlap-resolution logic ensures non-intersecting cached extents.
- Background services
- write-back worker flushes dirty keys in order, preserving backing-device
crash consistency. This is important for checkpoint in cloud storage.
- garbage collector reclaims clean segments when utilisation exceeds a
tunable threshold.
- Data integrity – optional CRC32 on cached payload; metadata always protected.
Comparison with existing block-level caches
---------------------------------------------------------------------------------------------------------------------------------
| Feature | pcache (this patch) | bcache | dm-writecache |
|----------------------------------|---------------------------------|------------------------------|---------------------------|
| pmem access method | DAX | bio (block I/O) | DAX |
| Write latency (4 K rand-write) | ~5 µs | ~20 µs | ~5 µs |
| Concurrency | multi subtree index | global index tree | single tree + wc_lock |
| IOPS (4K randwrite, 32 numjobs) | 2.1 M | 352 K | 283 K |
| Read-cache support | YES | YES | NO |
| Deployment | no re-format of backend | backend devices must be | no re-format of backend |
| | | reformatted | |
| Write-back ordering | log-structured; | no ordering guarantee | no ordering guarantee |
| | preserves app-IO-order | | |
| Data integrity checks | metadata + data CRC(optional) | metadata CRC only | none |
---------------------------------------------------------------------------------------------------------------------------------
Signed-off-by: Dongsheng Yang <dongsheng.yang@linux.dev>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
|
|
There isn't yet a clear way to identify a set of "lost" time that
everyone (or at least a wider group of users) cares about. However,
users can perform some delay accounting by iterating over components of
interest. This patch allows cgroup v2 freezing time to be one of those
components.
Track the cumulative time that each v2 cgroup spends freezing and expose
it to userland via a new local stat file in cgroupfs. Thank you to
Michal, who provided the ASCII art in the updated documentation.
To access this value:
$ mkdir /sys/fs/cgroup/test
$ cat /sys/fs/cgroup/test/cgroup.stat.local
freeze_time_total 0
Ensure consistent freeze time reads with freeze_seq, a per-cgroup
sequence counter. Writes are serialized using the css_set_lock.
Signed-off-by: Tiffany Yang <ynaffit@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
- Fix NULL de-ref in css_rstat_exit() which could happen after
allocation failure
- Fix a cpuset partition handling bug and a couple other misc issues
- Doc spelling fix
* tag 'cgroup-for-6.17-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
docs: cgroup: fixed spelling mistakes in documentation
cgroup: avoid null de-ref in css_rstat_exit()
cgroup/cpuset: Remove the unnecessary css_get/put() in cpuset_partition_write()
cgroup/cpuset: Fix a partition error with CPU hotplug
cgroup/cpuset: Use static_branch_enable_cpuslocked() on cpusets_insane_config_key
|
|
Cross-merge networking fixes after downstream PR (net-6.17-rc3).
No conflicts or adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Add a few missing directories under /proc/sys.
Fix punctuation and doubled words.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Reviewed-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250819075456.113623-1-rdunlap@infradead.org
|
|
Fix documentation issues by removing a duplicated word and adding the
missing SPDX-License identifier.
Signed-off-by: Bartlomiej Kubik <kubik.bartlomiej@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250819113551.34356-1-kubik.bartlomiej@gmail.com
|
|
When CONFIG_TMPFS is enabled, the initial root filesystem is a tmpfs.
By default, a tmpfs mount is limited to using 50% of the available RAM
for its content. This can be problematic in memory-constrained
environments, particularly during a kdump capture.
In a kdump scenario, the capture kernel boots with a limited amount of
memory specified by the 'crashkernel' parameter. If the initramfs is
large, it may fail to unpack into the tmpfs rootfs due to insufficient
space. This is because to get X MB of usable space in tmpfs, 2*X MB of
memory must be available for the mount. This leads to an OOM failure
during the early boot process, preventing a successful crash dump.
This patch introduces a new kernel command-line parameter,
initramfs_options, which allows passing specific mount options directly
to the rootfs when it is first mounted. This gives users control over
the rootfs behavior.
For example, a user can now specify initramfs_options=size=75% to allow
the tmpfs to use up to 75% of the available memory. This can
significantly reduce the memory pressure for kdump.
Consider a practical example:
To unpack a 48MB initramfs, the tmpfs needs 48MB of usable space. With
the default 50% limit, this requires a memory pool of 96MB to be
available for the tmpfs mount. The total memory requirement is therefore
approximately: 16MB (vmlinuz) + 48MB (loaded initramfs) + 48MB (unpacked
kernel) + 96MB (for tmpfs) + 12MB (runtime overhead) ≈ 220MB.
By using initramfs_options=size=75%, the memory pool required for the
48MB tmpfs is reduced to 48MB / 0.75 = 64MB. This reduces the total
memory requirement by 32MB (96MB - 64MB), allowing the kdump to succeed
with a smaller crashkernel size, such as 192MB.
An alternative approach of reusing the existing rootflags parameter was
considered. However, a new, dedicated initramfs_options parameter was
chosen to avoid altering the current behavior of rootflags (which
applies to the final root filesystem) and to prevent any potential
regressions.
Also add documentation for the new kernel parameter "initramfs_options"
This approach is inspired by prior discussions and patches on the topic.
Ref: https://www.lightofdawn.org/blog/?viewDetailed=00128
Ref: https://landley.net/notes-2015.html#01-01-2015
Ref: https://lkml.org/lkml/2021/6/29/783
Ref: https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html#what-is-rootfs
Signed-off-by: Lichen Liu <lichliu@redhat.com>
Link: https://lore.kernel.org/20250815121459.3391223-1-lichliu@redhat.com
Tested-by: Rob Landley <rob@landley.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
|
SO_RCVBUF and SO_SNDBUF have limited range today, unless
distros or system admins change rmem_max and wmem_max.
Even iproute2 uses 1 MB SO_RCVBUF which is capped by
the kernel.
Decouple [rw]mem_max and [rw]mem_default and increase
[rw]mem_max to 4 MB.
Before:
$ sysctl net.core.rmem_default net.core.rmem_max net.core.wmem_default net.core.wmem_max
net.core.rmem_default = 212992
net.core.rmem_max = 212992
net.core.wmem_default = 212992
net.core.wmem_max = 212992
After:
$ sysctl net.core.rmem_default net.core.rmem_max net.core.wmem_default net.core.wmem_max
net.core.rmem_default = 212992
net.core.rmem_max = 4194304
net.core.wmem_default = 212992
net.core.wmem_max = 4194304
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Link: https://patch.msgid.link/20250819174030.1986278-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
dm-vdo docs currently has no explicit title heading but instead there
are multiple section headings as top-level heading. As such, these
sections are rendered as titles and inflates number of entries in the
toctree index.
Promote the first section heading ("dm-vdo") to title heading.
Fixes: 04bf7ac646ab ("dm: add documentation for dm-vdo target")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
|
|
found/fixed the following typos
- flushs -> flushes
in `Documentation/admin-guide/device-mapper/delay.rst`
Signed-off-by: Soham Metha <sohammetha01@gmail.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
|
|
Fixed the following typos in device-mapper documentation:
- explicitely -> explicitly
- approriate -> appropriate
Signed-off-by: Shubham Sharma <slopixelz@gmail.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
|
|
Reiserfs has been removed in 6.13, there are still some mentions in the
documentation about it and the tools. Remove those that don't seem
relevant anymore but keep references to reiserfs' r5 hash used by some
code.
There's one change in a script scripts/selinux/install_policy.sh but it
does not seem to be relevant either.
Signed-off-by: David Sterba <dsterba@suse.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250813100053.1291961-1-dsterba@suse.com
|
|
A big set of typo fixes from Bjorn Helgaas
|
|
Fix typos.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250813200526.290420-4-helgaas@kernel.org
|
|
Fix kernel-doc warning in kernel-parameters.txt
WARNING: Possible repeated word: 'is'
Signed-off-by: Vivek Yadav <vivekyadav1207731111@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250816082452.219009-1-vivekyadav1207731111@gmail.com
|
|
The papers are published by Intel, AMD and MIPS.
Signed-off-by: Nikola Z. Ivanov <zlatistiv@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20250816190028.55573-1-zlatistiv@gmail.com
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Remove a transitional asm/cpuid.h header which was added only as a
fallback during cpuid helpers reorg
- Initialize reserved fields in the SVSM page validation calls
structure to zero in order to allow for future structure extensions
- Have the sev-guest driver's buffers used in encryption operations be
in linear mapping space as the encryption operation can be offloaded
to an accelerator
- Have a read-only MSR write when in an AMD SNP guest trap to the
hypervisor as it is usually done. This makes the guest user
experience better by simply raising a #GP instead of terminating said
guest
- Do not output AVX512 elapsed time for kernel threads because the data
is wrong and fix a NULL pointer dereferencing in the process
- Adjust the SRSO mitigation selection to the new attack vectors
* tag 'x86_urgent_for_v6.17_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpuid: Remove transitional <asm/cpuid.h> header
x86/sev: Ensure SVSM reserved fields in a page validation entry are initialized to zero
virt: sev-guest: Satisfy linear mapping requirement in get_derived_key()
x86/sev: Improve handling of writes to intercepted TSC MSRs
x86/fpu: Fix NULL dereference in avx512_status()
x86/bugs: Select best SRSO mitigation
|
|
Enable the previously added mitigation for VMscape. Add the cmdline
vmscape={off|ibpb|force} and sysfs reporting.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
|
|
VMSCAPE is a vulnerability that may allow a guest to influence the branch
prediction in host userspace, particularly affecting hypervisors like QEMU.
Add the documentation.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
|
