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2026-02-05nvme: add support for dynamic quirk configuration via module parameterMaurizio Lombardi
Introduce support for enabling or disabling specific NVMe quirks at module load time through the `quirks` module parameter. This mechanism allows users to apply known quirks dynamically based on the device's PCI vendor and device IDs, without requiring to add hardcoded entries in the driver and recompiling the kernel. While the generic PCI new_id sysfs interface exists for dynamic configuration, it is insufficient for scenarios where the system fails to boot (for example, this has been reported to happen because of the bogus_nid quirk). The new_id attribute is writable only after the system has booted and sysfs is mounted. The `quirks` parameter accepts a list of quirk specifications separated by a '-' character in the following format: <VID>:<DID>:<quirk_names>[-<VID>:<DID>:<quirk_names>-..] Each quirk is represented by its name and can be prefixed with `^` to indicate that the quirk should be disabled; quirk names are separated by a ',' character. Example: enable BOGUS_NID and BROKEN_MSI, disable DEALLOCATE_ZEROES: $ modprobe nvme quirks=7170:2210:bogus_nid,broken_msi,^deallocate_zeroes Tested-by: Daniel Wagner <dwagner@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Signed-off-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-02-05bootconfig: Terminate value search if it hits a newlineMasami Hiramatsu (Google)
Terminate the value search for a key if it hits a newline and make the value empty. When we pass a bootconfig with an empty value terminated by the newline, like below:: foo = bar = value Current bootconfig interprets it as a single entry:: foo = "bar = value"; The Documentation/admin-guide/bootconfig.rst defines the value itself is terminated by newline: The value has to be terminated by semi-colon (``;``) or newline (``\n``). but it does not define when the value search is terminated. This changes the behavior to be more line-oriented, so that it is clearer in how it works. - The value search of key-value pair will be terminated by a comment or newline. - The value search of an array will continue beyond comments and newlines. Thus, with this update, the above example is interpreted as:: foo = ""; bar = "value"; And the below example will cause a syntax error because "bar" is expected as a key but it has ','. foo = bar, buz According to this change, one wrong example config is updated. Link: https://lore.kernel.org/all/177025238503.14982.17059549076175612447.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Julius Werner <jwerner@chromium.org>
2026-02-04Merge tag 'mm-hotfixes-stable-2026-02-04-15-55' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "Five hotfixes. Two are cc:stable, two are for MM. All are singletons - please see the changelogs for details" * tag 'mm-hotfixes-stable-2026-02-04-15-55' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: Documentation: document liveupdate cmdline parameter mm, shmem: prevent infinite loop on truncate race mailmap: update Alexander Mikhalitsyn's emails liveupdate: luo_file: do not clear serialized_data on unfreeze x86/kfence: fix booting on 32bit non-PAE systems
2026-02-03cpufreq: Documentation: Update description of rate_limit_us default valueYaxiong Tian
Due to commit 37c6dccd6837 ("cpufreq: Remove LATENCY_MULTIPLIER") updating the acquisition logic of cpufreq_policy_transition_delay_us(), the original description of 2 ms has become inaccurate. Therefore, update the description of the default value for rate_limit_us from 2ms to 1ms. Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn> [ rjw: Subject and changelog edits ] Link: https://patch.msgid.link/20260203093501.1138721-1-tianyaxiong@kylinos.cn Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2026-02-03workqueue: add CONFIG_BOOTPARAM_WQ_STALL_PANIC optionBreno Leitao
Add a kernel config option to set the default value of workqueue.panic_on_stall, similar to CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC, CONFIG_BOOTPARAM_HARDLOCKUP_PANIC and CONFIG_BOOTPARAM_HUNG_TASK_PANIC. This allows setting the number of workqueue stalls before triggering a kernel panic at build time, which is useful for high-availability systems that need consistent panic-on-stall, in other words, those servers which run with CONFIG_BOOTPARAM_*_PANIC=y already. The default remains 0 (disabled). Setting it to 1 will panic on the first stall, and higher values will panic after that many stall warnings. The value can still be overridden at runtime via the workqueue.panic_on_stall boot parameter or sysfs. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-02-03panic: add panic_force_cpu= parameter to redirect panic to a specific CPUPnina Feder
Some platforms require panic handling to execute on a specific CPU for crash dump to work reliably. This can be due to firmware limitations, interrupt routing constraints, or platform-specific requirements where only a single CPU is able to safely enter the crash kernel. Add the panic_force_cpu= kernel command-line parameter to redirect panic execution to a designated CPU. When the parameter is provided, the CPU that initially triggers panic forwards the panic context to the target CPU via IPI, which then proceeds with the normal panic and kexec flow. The IPI delivery is implemented as a weak function (panic_smp_redirect_cpu) so architectures with NMI support can override it for more reliable delivery. If the specified CPU is invalid, offline, or a panic is already in progress on another CPU, the redirection is skipped and panic continues on the current CPU. [pnina.feder@mobileye.com: fix unused variable warning] Link: https://lkml.kernel.org/r/20260126122618.2967950-1-pnina.feder@mobileye.com Link: https://lkml.kernel.org/r/20260122102457.1154599-1-pnina.feder@mobileye.com Signed-off-by: Pnina Feder <pnina.feder@mobileye.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Baoquan He <bhe@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-03Merge branch 'v6.19-rc8'Peter Zijlstra
Update to avoid conflicts with /urgent patches. Signed-off-by: Peter Zijlstra <peterz@infradead.org>
2026-02-02Documentation: document liveupdate cmdline parameterLi Chen
liveupdate is used to enable Live Update Orchestrator (LUO) early during boot. Add it to kernel-parameters.txt so users can discover and use it. Link: https://lkml.kernel.org/r/20260130112036.359806-1-me@linux.beauty Signed-off-by: Li Chen <me@linux.beauty> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Frank van der Linden <fvdl@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <kees@kernel.org> Cc: Li RongQing <lirongqing@baidu.com> Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-02modsign: Enable ML-DSA module signingDavid Howells
Allow ML-DSA module signing to be enabled. Note that OpenSSL's CMS_*() function suite does not, as of OpenSSL-3.6, support the use of CMS_NOATTR with ML-DSA, so the prohibition against using signedAttrs with module signing has to be removed. The selected digest then applies only to the algorithm used to calculate the digest stored in the messageDigest attribute. The OpenSSL development branch has patches applied that fix this[1], but it appears that that will only be available in OpenSSL-4. [1] https://github.com/openssl/openssl/pull/28923 sign-file won't set CMS_NOATTR if openssl is earlier than v4, resulting in the use of signed attributes. The ML-DSA algorithm takes the raw data to be signed without regard to what digest algorithm is specified in the CMS message. The CMS specified digest algorithm is ignored unless signedAttrs are used; in such a case, only SHA512 is permitted. Signed-off-by: David Howells <dhowells@redhat.com> cc: Jarkko Sakkinen <jarkko@kernel.org> cc: Eric Biggers <ebiggers@kernel.org> cc: Lukas Wunner <lukas@wunner.de> cc: Ignat Korchagin <ignat@cloudflare.com> cc: Stephan Mueller <smueller@chronox.de> cc: Herbert Xu <herbert@gondor.apana.org.au> cc: keyrings@vger.kernel.org cc: linux-crypto@vger.kernel.org
2026-02-02docs: fix 're-use' -> 'reuse' in documentationRhys Tumelty
Signed-off-by: Rhys Tumelty <rhys@tumelty.co.uk> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260128220233.179439-1-rhys@tumelty.co.uk>
2026-01-31Docs/admin-guide/mm/damon/usage: update stats update process for refresh_msSeongJae Park
DAMOS stats on sysfs was only manually updated. Recent addition of 'refresh_ms' knob enabled periodic and automated updates of the stats. The document for stats update process is not updated for the change, however. Update. Link: https://lkml.kernel.org/r/20260118180305.70023-7-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31Docs/admin-guide/mm/damon/usage: introduce DAMON modules at the beginningSeongJae Park
DAMON usage document provides a list of available DAMON interfaces with brief introduction at the beginning of the doc. The list is missing DAMON modules for special purposes, while it is one of the major suggested interfaces. Add an item for those to the list. Link: https://lkml.kernel.org/r/20260118180305.70023-6-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-31mm: rename CONFIG_BALLOON_COMPACTION to CONFIG_BALLOON_MIGRATIONDavid Hildenbrand (Red Hat)
While compaction depends on migration, the other direction is not the case. So let's make it clearer that this is all about migration of balloon pages. Adjust all comments/docs in the core to talk about "migration" instead of "compaction". While at it add some "/* CONFIG_BALLOON_MIGRATION */". Link: https://lkml.kernel.org/r/20260119230133.3551867-23-david@kernel.org Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Eugenio Pérez <eperezma@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jason Wang <jasowang@redhat.com> Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: SeongJae Park <sj@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-30xfs: allow setting errortags at mount timeChristoph Hellwig
Add an errortag mount option that enables an errortag with the default injection frequency. This allows injecting errors into the mount process instead of just on live file systems, and thus test mount error handling. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by: Carlos Maiolino <cem@kernel.org>
2026-01-30docs: trusted-encryped: add PKWM as a new trust sourceNayna Jain
Update Documentation/security/keys/trusted-encrypted.rst and Documentation/ admin-guide/kernel-parameters.txt with PowerVM Key Wrapping Module (PKWM) as a new trust source Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Signed-off-by: Srish Srinivasan <ssrish@linux.ibm.com> Tested-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20260127145228.48320-7-ssrish@linux.ibm.com
2026-01-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.19-rc8). No adjacent changes, conflicts: drivers/net/ethernet/spacemit/k1_emac.c 2c84959167d64 ("net: spacemit: Check for netif_carrier_ok() in emac_stats_update()") f66086798f91f ("net: spacemit: Remove broken flow control support") https://lore.kernel.org/aXjAqZA3iEWD_DGM@sirena.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-29riscv: add kernel command line option to opt out of user CFIDeepak Gupta
Add a kernel command line option to disable part or all of user CFI. User backward CFI and forward CFI can be controlled independently. The kernel command line parameter "riscv_nousercfi" can take the following values: - "all" : Disable forward and backward cfi both - "bcfi" : Disable backward cfi - "fcfi" : Disable forward cfi Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-21-b55691eacf4f@rivosinc.com [pjw@kernel.org: fixed warnings from checkpatch; cleaned up patch description, doc, printk text] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-26Docs/admin-guide/mm/damon/lru_sort: document intervals autotuningSeongJae Park
Document a newly added DAMON_LRU_SORT module parameter for using monitoring intervals auto-tuning feature of DAMON. Link: https://lkml.kernel.org/r/20260113152717.70459-12-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26Docs/admin-guide/mm/damon/lru_sort: document active_mem_bp parameterSeongJae Park
Document a newly added DAMON_LRU_SORT parameter for doing auto-tuning aiming an active to inactive memory size ratio. Link: https://lkml.kernel.org/r/20260113152717.70459-10-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26Docs/admin-guide/mm/damon/lru_sort: document filter_young_pagesSeongJae Park
Document the new DAMON_LRU_SORT parameter, filter_young_pages. It can be used to use page level access re-check for the LRU sorting. Link: https://lkml.kernel.org/r/20260113152717.70459-8-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Acked-by: wang lian <lianux.mm@gmail.com> Cc: David Hildenbrand <david@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> 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> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26memcg-v1: remove folio_memcg_lock() doc referenceGreg Thelen
Commit a29c0e4b2e86 ("memcg-v1: remove memcg move locking code") removed folio_memcg_lock(). Delete the final lingering documentation reference. Link: https://lkml.kernel.org/r/20260101225552.3423108-1-gthelen@google.com Fixes: a29c0e4b2e86 ("memcg-v1: remove memcg move locking code") Signed-off-by: Greg Thelen <gthelen@google.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: SeongJae Park <sj@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Michal Koutný" <mkoutny@suse.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26Merge tag 'vfs-6.19-rc8.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: - Fix the the buggy conversion of fuse_reverse_inval_entry() introduced during the creation rework - Disallow nfs delegation requests for directories by setting simple_nosetlease() - Require an opt-in for getting readdir flag bits outside of S_DT_MASK set in d_type - Fix scheduling delayed writeback work by only scheduling when the dirty time expiry interval is non-zero and cancel the delayed work if the interval is set to zero - Use rounded_jiffies_interval for dirty time work - Check the return value of sb_set_blocksize() for romfs - Wait for batched folios to be stable in __iomap_get_folio() - Use private naming for fuse hash size - Fix the stale dentry cleanup to prevent a race that causes a UAF * tag 'vfs-6.19-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: vfs: document d_dispose_if_unused() fuse: shrink once after all buckets have been scanned fuse: clean up fuse_dentry_tree_work() fuse: add need_resched() before unlocking bucket fuse: make sure dentry is evicted if stale fuse: fix race when disposing stale dentries fuse: use private naming for fuse hash size writeback: use round_jiffies_relative for dirtytime_work iomap: wait for batched folios to be stable in __iomap_get_folio romfs: check sb_set_blocksize() return value docs: clarify that dirtytime_expire_seconds=0 disables writeback writeback: fix 100% CPU usage when dirtytime_expire_interval is 0 readdir: require opt-in for d_type flags vboxsf: don't allow delegations to be set on directories ceph: don't allow delegations to be set on directories gfs2: don't allow delegations to be set on directories 9p: don't allow delegations to be set on directories smb/client: properly disallow delegations on directories nfs: properly disallow delegation requests on directories fuse: fix conversion of fuse_reverse_inval_entry() to start_removing()
2026-01-26Merge branch 'fixes' of into for-nextIlpo Järvinen
2026-01-26Merge 6.19-rc7 into char-misc-nextGreg Kroah-Hartman
We need the char/misc/iio fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-25net: expand NETDEV_RSS_KEY_LEN to 256 bytesEric Dumazet
NETDEV_RSS_KEY_LEN has been set to 52 bytes in 2014, until now. Jakub suggested we bump the size to 128 bytes or more. Some drivers (like idpf) were already working around the core limit. Since this change might cause some issues in admin scripts, bump it directly to 256 in one go. tjbp26:~# cat /proc/sys/net/core/netdev_rss_key | wc -c 768 tjbp26:~# ethtool -x eth1 RX flow hash indirection table for eth1 with 32 RX ring(s): ... RSS hash key: fe:16:5b:2f:93:85:c2:c9:c1:ef:bd:60:c6:e0:2b:99:4d:bf:b7:14:c8:1e:8d:cb:31:17:51:da:55:eb:91:d9:9e:f9:89:9b:44:a1:dc:08:72:3a:b3:d6:31:86:9a:fe:02:3a:0d:eb:a1:7c:f5:a3:51:3b:08:56:c9:3f:71:69:01:ba:70:38 RSS hash function: toeplitz: on xor: off crc32: off Suggested-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/netdev/20260122075206.504ec591@kernel.org/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260122190349.2771064-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-23Merge tag 'platform-drivers-x86-v6.19-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull x86 platform driver fixes from Ilpo Järvinen: - acer-wmi: - Extend support for Acer Nitro AN515-58 - Fix missing capability check - amd/wbrf: Fix memory leak in wbrf_record() - asus-armoury: - Fix GA403U* matching - Fix FA608UM TDP data - Add many models - asus-wmi: Move OOBE presence check outside deprecation ifdef - hp-bioscfg: - Fix kernel panic in GET_INSTANCE_ID macro - Fix kobject warnings for empty attribute names - Correct GUID to uppercase (lowercase letter prevented autoloading the module) - mellanox: Fix SN5640/SN5610 LED platform data - docs: - alienware-wmi: Typo fix - amd_hsmp: Fix document link * tag 'platform-drivers-x86-v6.19-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (21 commits) platform/x86: acer-wmi: Fix missing capability check platform/x86: acer-wmi: Extend support for Acer Nitro AN515-58 platform/x86: asus-armoury: add support for GA403WW platform/x86: asus-armoury: keep the list ordered alphabetically platform/x86: asus-armoury: add support for G835L platform/x86: asus-armoury: fix ppt data for FA608UM platform/x86: hp-bioscfg: Fix automatic module loading platform/x86: hp-bioscfg: Fix kernel panic in GET_INSTANCE_ID macro platform/x86: hp-bioscfg: Fix kobject warnings for empty attribute names platform/x86: asus-wmi: fix sending OOBE at probe platform/x86: asus-armoury: add support for FA617XT platform/x86: asus-armoury: add support for FA401UV platform/x86: asus-armoury: add support for GV302XV platform/x86: asus-armoury: Add power limits for Asus G513QY platform/x86/amd: Fix memory leak in wbrf_record() platform/mellanox: Fix SN5640/SN5610 LED platform data docs: fix PPR for AMD EPYC broken link docs: alienware-wmi: fix typo platform/x86: asus-armoury: add support for GA403UV asus-armoury: fix ppt data for GA403U* renaming to GA403UI ...
2026-01-23Documentation: use a source-read extension for the index link boilerplateJani Nikula
The root document usually has a special :ref:`genindex` link to the generated index. This is also the case for Documentation/index.rst. The other index.rst files deeper in the directory hierarchy usually don't. For SPHINXDIRS builds, the root document isn't Documentation/index.rst, but some other index.rst in the hierarchy. Currently they have a ".. only::" block to add the index link when doing SPHINXDIRS html builds. This is obviously very tedious and repetitive. The link is also added to all index.rst files in the hierarchy for SPHINXDIRS builds, not just the root document. Put the boilerplate in a sphinx-includes/subproject-index.rst file, and include it at the end of the root document for subproject builds in an ad-hoc source-read extension defined in conf.py. For now, keep having the boilerplate in translations, because this approach currently doesn't cover translated index link headers. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Tested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> [jc: did s/doctree/kern_doc_dir/ ] Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260123143149.2024303-1-jani.nikula@intel.com>
2026-01-22rseq: Move slice_ext_nsec to debugfsPeter Zijlstra
Move changing the slice ext duration to debugfs, a sliglty less permanent interface. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260121143207.923520192@infradead.org
2026-01-22rseq: Implement time slice extension enforcement timerThomas Gleixner
If a time slice extension is granted and the reschedule delayed, the kernel has to ensure that user space cannot abuse the extension and exceed the maximum granted time. It was suggested to implement this via the existing hrtick() timer in the scheduler, but that turned out to be problematic for several reasons: 1) It creates a dependency on CONFIG_SCHED_HRTICK, which can be disabled independently of CONFIG_HIGHRES_TIMERS 2) HRTICK usage in the scheduler can be runtime disabled or is only used for certain aspects of scheduling. 3) The function is calling into the scheduler code and that might have unexpected consequences when this is invoked due to a time slice enforcement expiry. Especially when the task managed to clear the grant via sched_yield(0). It would be possible to address #2 and #3 by storing state in the scheduler, but that is extra complexity and fragility for no value. Implement a dedicated per CPU hrtimer instead, which is solely used for the purpose of time slice enforcement. The timer is armed when an extension was granted right before actually returning to user mode in rseq_exit_to_user_mode_restart(). It is disarmed, when the task relinquishes the CPU. This is expensive as the timer is probably the first expiring timer on the CPU, which means it has to reprogram the hardware. But that's less expensive than going through a full hrtimer interrupt cycle for nothing. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/20251215155709.068329497@linutronix.de
2026-01-22rseq: Provide static branch for time slice extensionsThomas Gleixner
Guard the time slice extension functionality with a static key, which can be disabled on the kernel command line. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20251215155708.733429292@linutronix.de
2026-01-21cgroup: Remove stale cpu.rt.max reference from documentationTejun Heo
cpu.rt.max was a proposed interface that never landed in mainline. Remove the reference from cgroup-v2 documentation. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Orestis Floros <orestisflo@gmail.com>
2026-01-20watchdog: softlockup: panic when lockup duration exceeds N thresholdsLi RongQing
The softlockup_panic sysctl is currently a binary option: panic immediately or never panic on soft lockups. Panicking on any soft lockup, regardless of duration, can be overly aggressive for brief stalls that may be caused by legitimate operations. Conversely, never panicking may allow severe system hangs to persist undetected. Extend softlockup_panic to accept an integer threshold, allowing the kernel to panic only when the normalized lockup duration exceeds N watchdog threshold periods. This provides finer-grained control to distinguish between transient delays and persistent system failures. The accepted values are: - 0: Don't panic (unchanged) - 1: Panic when duration >= 1 * threshold (20s default, original behavior) - N > 1: Panic when duration >= N * threshold (e.g., 2 = 40s, 3 = 60s.) The original behavior is preserved for values 0 and 1, maintaining full backward compatibility while allowing systems to tolerate brief lockups while still catching severe, persistent hangs. [lirongqing@baidu.com: v2] Link: https://lkml.kernel.org/r/20251218074300.4080-1-lirongqing@baidu.com Link: https://lkml.kernel.org/r/20251216074521.2796-1-lirongqing@baidu.com Signed-off-by: Li RongQing <lirongqing@baidu.com> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20mm, hugetlb: implement movable_gigantic_pages sysctlGregory Price
This reintroduces a concept removed by: commit d6cb41cc44c6 ("mm, hugetlb: remove hugepages_treat_as_movable sysctl") This sysctl provides flexibility between ZONE_MOVABLE use cases: 1) onlining memory in ZONE_MOVABLE to maintain hotplug compatibility 2) onlining memory in ZONE_MOVABLE to make hugepage allocate reliable When ZONE_MOVABLE is used to make huge page allocation more reliable, disallowing gigantic pages memory in this region is pointless. If hotplug is not a requirement, we can loosen the restrictions to allow 1GB gigantic pages in ZONE_MOVABLE. Since 1GB can be difficult to migrate / has impacts on compaction / defragmentation, we don't enable this by default. Notably, 1GB pages can only be migrated if another 1GB page is available - so hot-unplug will fail if such a page cannot be found. However, since there are scenarios where gigantic pages are migratable, we should allow use of these on movable regions. When not valid 1GB is available for migration, hot-unplug will retry indefinitely (or until interrupted). For example: echo 0 > node0/hugepages/..-1GB/nr_hugepages # clear node0 1GB pages echo 1 > node1/hugepages/..-1GB/nr_hugepages # reserve node1 1GB page ./alloc_huge_node1 & # Allocate a 1GB page on node1 ./node1_offline & # attempt to offline all node1 memory echo 1 > node0/hugepages/..-1GB/nr_hugepages # reserve node0 1GB page In this example, node1_offline will block indefinitely until the final step, when a node0 1GB page is made available. Note: Boot-time CMA is not possible for driver-managed hotplug memory, as CMA requires the memory to be registered as SystemRAM at boot time. Additionally, 1GB huge pages are not supported by THP. Link: https://lkml.kernel.org/r/20251221125603.2364174-1-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Suggested-by: David Rientjes <rientjes@google.com> Link: https://lore.kernel.org/all/20180201193132.Hk7vI_xaU%25akpm@linux-foundation.org/ Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: "David Hildenbrand (Red Hat)" <david@kernel.org> Cc: Gregory Price <gourry@gourry.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20mm/block/fs: remove laptop_modeJohannes Weiner
Laptop mode was introduced to save battery, by delaying and consolidating writes and thereby maximize the time rotating hard drives wouldn't have to spin. Luckily, rotating hard drives, with their high spin-up times and power draw, are a thing of the past for battery-powered devices. Reclaim has also since changed to not write single filesystem pages anymore, and regular filesystem writeback is lumpy by design. The juice doesn't appear worth the squeeze anymore. The footprint of the feature is small, but nevertheless it's a complicating factor in mm, block, filesystems. Developers don't think about it, and it likely hasn't been tested with new reclaim and writeback changes in years. Let's sunset it. Keep the sysctl with a deprecation warning around for a few more cycles, but remove all functionality behind it. [akpm@linux-foundation.org: fix Documentation/admin-guide/laptops/index.rst] Link: https://lkml.kernel.org/r/20251216185201.GH905277@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Deepanshu Kartikey <kartikey406@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20Docs/admin-guide/mm/damon/usage: update for max_nr_snapshotsSeongJae Park
Update DAMON usage document for the newly added DAMON sysfs interface file, max_nr_snapshots. Link: https://lkml.kernel.org/r/20251216080128.42991-11-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20Docs/admin-guide/mm/damon/usage: update for nr_snapshots damos statSeongJae Park
Update DAMON usage document for the newly added damos stat, nr_snapshots. Link: https://lkml.kernel.org/r/20251216080128.42991-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20zram: document writeback_batch_sizeSergey Senozhatsky
Add missing writeback_batch_size documentation. Link: https://lkml.kernel.org/r/20251201094754.4149975-4-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: David Stevens <stevensd@google.com> Cc: Minchan Kim <minchan@google.com> Cc: Richard Chang <richardycc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20zram: introduce writeback_compressed device attributeRichard Chang
Introduce witeback_compressed device attribute to toggle compressed writeback (decompression on demand) feature. [senozhatsky@chromium.org: rewrote original patch, added documentation] Link: https://lkml.kernel.org/r/20251201094754.4149975-3-senozhatsky@chromium.org Signed-off-by: Richard Chang <richardycc@google.com> Co-developed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Brian Geffon <bgeffon@google.com> Cc: David Stevens <stevensd@google.com> Cc: Minchan Kim <minchan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20Docs/mm/allocation-profiling: describe sysctrl limitations in debug modeSuren Baghdasaryan
When CONFIG_MEM_ALLOC_PROFILING_DEBUG=y, /proc/sys/vm/mem_profiling is read-only to avoid debug warnings in a scenario when an allocation is made while profiling is disabled (allocation does not get an allocation tag), then profiling gets enabled and allocation gets freed (warning due to the allocation missing allocation tag). Link: https://lkml.kernel.org/r/20260116184423.2708363-1-surenb@google.com Fixes: ebdf9ad4ca98 ("memprofiling: documentation") Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Ran Xiaokai <ran.xiaokai@zte.com.cn> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-19dm-verity: add dm-verity keyringChristian Brauner
Add a dedicated ".dm-verity" keyring for root hash signature verification, similar to the ".fs-verity" keyring used by fs-verity. By default the keyring is unused retaining the exact same old behavior. For systems that provision additional keys only intended for dm-verity images during boot, the dm_verity.keyring_unsealed=1 kernel parameter leaves the keyring open. We want to use this in systemd as a way add keys during boot that are only used for creating dm-verity devices for later mounting and nothing else. The discoverable disk image (DDI) spec at [1] heavily relies on dm-verity and we would like to expand this even more. This will allow us to do that in a fully backward compatible way. Once provisioning is complete, userspace restricts and activates it for dm-verity verification. If userspace fully seals the keyring then it gains the guarantee that no new keys can be added. Link: https://uapi-group.org/specifications/specs/discoverable_partitions_specification [1] Co-developed-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2026-01-17x86/acpi: Add acpi=spcr to use SPCR-provided default consoleShenghao Yang
The SPCR provided console on x86 is only available as a boot console when earlycon is provided on the kernel command line, and will not be present in /proc/consoles. While it's possible to retain the boot console with the keep_bootcon parameter, that leaves the console using the less efficient 8250_early driver. Users wanting to use the firmware suggested console (to avoid maintaining unique serial console parameters for different server models in large fleets) with the conventional driver have to parse the kernel log for the console parameters and reinsert them. [ 0.005091] ACPI: SPCR 0x000000007FFB5000 000059 (v04 ALASKA A M I 01072009 INTL 20250404) [ 0.073387] ACPI: SPCR: console: uart,io,0x3f8,115200 In commit 0231d00082f6 ("ACPI: SPCR: Make SPCR available to x86")¹ the SPCR console was only added as an option for earlycon but not as an ordinary console so users don't see console output changes. So users can opt in to an automatic SPCR console, make ACPI init add it if acpi=spcr is set. ¹https://lore.kernel.org/lkml/20180118150951.28964-1-prarit@redhat.com/ [ bp: Touchups. ] Signed-off-by: Shenghao Yang <me@shenghaoyang.info> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260117072827.355360-1-me@shenghaoyang.info
2026-01-17Documentation: admin-guide: media: mgb4: Add GMSL1 & GMSL3-coax modules infoMartin Tůma
Add the mgb4 GMSL1 and GMSL3-coax modules info. Signed-off-by: Martin Tůma <martin.tuma@digiteqautomotive.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2026-01-16docs: make kptr_restrict and hash_pointers reference each otherMarc Herbert
vsprintf.c uses a mix of the `kernel.kptr_restrict` sysctl and the `hash_pointers` boot param to control pointer hashing. But that wasn't possible to tell without looking at the source code. They have a different focus and purpose. To avoid wasting the time of users trying to use one instead of the other, simply have them reference each other in the Documentation. Signed-off-by: Marc Herbert <marc.herbert@linux.intel.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260107-doc-hash-ptr-v2-1-cb4c161218d7@linux.intel.com>
2026-01-16Documentation: Fix typos and grammatical errorsNauman Sabir
Fix various typos and grammatical errors across documentation files: - Fix missing preposition 'in' in process/changes.rst - Correct 'result by' to 'result from' in admin-guide/README.rst - Fix 'before hand' to 'beforehand' in cgroup-v1/hugetlb.rst - Correct 'allows to limit' to 'allows limiting' in hugetlb.rst, cgroup-v2.rst, and kconfig-language.rst - Fix 'needs precisely know' to 'needs to precisely know' - Correct 'overcommited' to 'overcommitted' in hugetlb.rst - Fix subject-verb agreement: 'never causes' to 'never cause' - Fix 'there is enough' to 'there are enough' in hugetlb.rst - Fix 'metadatas' to 'metadata' in filesystems/erofs.rst - Fix 'hardwares' to 'hardware' in scsi/ChangeLog.sym53c8xx Signed-off-by: Nauman Sabir <officialnaumansabir@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Message-ID: <20260115230110.7734-1-officialnaumansabir@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2026-01-15Merge tag 'mm-hotfixes-stable-2026-01-15-08-03' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: - kerneldoc fixes from Bagas Sanjaya - DAMON fixes from SeongJae - mremap VMA-related fixes from Lorenzo - various singletons - please see the changelogs for details * tag 'mm-hotfixes-stable-2026-01-15-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (30 commits) drivers/dax: add some missing kerneldoc comment fields for struct dev_dax mm: numa,memblock: include <asm/numa.h> for 'numa_nodes_parsed' mailmap: add entry for Daniel Thompson tools/testing/selftests: fix gup_longterm for unknown fs mm/page_alloc: prevent pcp corruption with SMP=n iommu/sva: include mmu_notifier.h header mm: kmsan: fix poisoning of high-order non-compound pages tools/testing/selftests: add forked (un)/faulted VMA merge tests mm/vma: enforce VMA fork limit on unfaulted,faulted mremap merge too tools/testing/selftests: add tests for !tgt, src mremap() merges mm/vma: fix anon_vma UAF on mremap() faulted, unfaulted merge mm/zswap: fix error pointer free in zswap_cpu_comp_prepare() mm/damon/sysfs-scheme: cleanup access_pattern subdirs on scheme dir setup failure mm/damon/sysfs-scheme: cleanup quotas subdirs on scheme dir setup failure mm/damon/sysfs: cleanup attrs subdirs on context dir setup failure mm/damon/sysfs: cleanup intervals subdirs on attrs dir setup failure mm/damon/core: remove call_control in inactive contexts powerpc/watchdog: add support for hardlockup_sys_info sysctl mips: fix HIGHMEM initialization mm/hugetlb: ignore hugepage kernel args if hugepages are unsupported ...
2026-01-15platform/x86: thinkpad_acpi: Add sysfs to display details of damaged device.Nitin Joshi
Add new sysfs interface to identify the impacted component with location of device. Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca> Signed-off-by: Nitin Joshi <nitjoshi@gmail.com> Link: https://patch.msgid.link/20260106174519.6402-2-nitjoshi@gmail.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2026-01-15platform/x86: thinkpad_acpi: Add support to detect hardware damage detection ↵Nitin Joshi
capability. Thinkpads are adding the ability to detect and report hardware damage status. Add new sysfs interface to identify whether hardware damage is detected or not. Initial support is available for the USB-C replaceable connector. Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca> Signed-off-by: Nitin Joshi <nitjoshi@gmail.com> Link: https://patch.msgid.link/20260106174519.6402-1-nitjoshi@gmail.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2026-01-14docs: kernel-parameters: add kfence parametersMarco Elver
Add a brief summary for KFENCE's kernel command-line parameters in admin-guide/kernel-parameters. Link: https://lkml.kernel.org/r/20251222150018.1349672-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-14xen: introduce xen_console_io optionStefano Stabellini
Xen can support console_io hypercalls for any domains, not just dom0, depending on DEBUG and XSM policies. These hypercalls can be very useful for development and debugging. Introduce a kernel command line option xen_console_io to enable the usage of console_io hypercalls for any domain upon request. When xen_console_io is not specified, the current behavior is retained. Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Message-ID: <alpine.DEB.2.22.394.2601131522540.992863@ubuntu-linux-20-04-desktop>
2026-01-13net: add net.core.qdisc_max_burstEric Dumazet
In blamed commit, I added a check against the temporary queue built in __dev_xmit_skb(). Idea was to drop packets early, before any spinlock was acquired. if (unlikely(defer_count > READ_ONCE(q->limit))) { kfree_skb_reason(skb, SKB_DROP_REASON_QDISC_DROP); return NET_XMIT_DROP; } It turned out that HTB Qdisc has a zero q->limit. HTB limits packets on a per-class basis. Some of our tests became flaky. Add a new sysctl : net.core.qdisc_max_burst to control how many packets can be stored in the temporary lockless queue. Also add a new QDISC_BURST_DROP drop reason to better diagnose future issues. Thanks Neal ! Fixes: 100dfa74cad9 ("net: dev_queue_xmit() llist adoption") Reported-and-bisected-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20260107104159.3669285-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>