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2026-06-30clk: renesas: rzv2h-cpg: Extract PLL calculation helpers into shared libraryLad Prabhakar
Move the RZ/V2H PLL and divider parameter calculation helpers from rzv2h-cpg.c into a new reusable library. Introduce the CLK_RZV2H_CPG_LIB Kconfig symbol and add rzv2h-cpg-lib.c to host the PLL parameter search algorithms currently implemented by rzv2h_get_pll_pars() and rzv2h_get_pll_divs_pars(). Export the helpers as rzv2h_cpg_get_pll_pars() and rzv2h_cpg_get_pll_divs_pars() for use by other drivers. Update the public clock header to expose the new interfaces and provide compatibility aliases for the existing helper names, avoiding build breakage for current users while allowing future conversions to the new API. This prepares for reuse of the PLL and divider calculation logic by other Renesas clock drivers, including upcoming RZ/T2H and RZ/N2H CPG support, without duplicating the implementation. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patch.msgid.link/20260618181949.3036280-5-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2026-06-30clk: renesas: rzv2h-cpg: Use per-SoC PLL reference frequency for calculationsLad Prabhakar
Introduce a per-SoC PLL reference input frequency parameter to avoid relying on a hardcoded 24MHz constant during PLL configuration math. Add an input_fref member to struct rzv2h_pll_limits. In the core calculation helper rzv2h_get_pll_pars(), derive the base input clock rate from limits->input_fref, utilizing the conditional ternary operator to fall back to 24MHz if the struct field is left uninitialized (0), and drop the obsolete macro RZ_V2H_OSC_CLK_IN_MEGA. This abstraction permits the reuse of the common PLL divider logic on newer SoC platforms like the RZ/T2H, which feature a 48 MHz PLL reference clock input instead of the 24 MHz signal used by RZ/V2H(P), without disrupting existing platforms. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patch.msgid.link/20260618181949.3036280-2-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2026-06-30Merge tag 'renesas-r9a09g077-dt-binding-defs-tag7' into renesas-clk-for-v7.3Geert Uytterhoeven
Renesas RZ/T2H and RZ/N2H LCDC and RTC Clock DT Binding Definitions LCD Controller and Real-Time Clock DT binding definitions for the Renesas RZ/T2H (R9A09G077) and RZ/N2H (R9A09G087) SoCs, shared by driver and DT source files.
2026-06-30drm/fixed: fix kernel-doc for drm_sm2fixp()Jani Nikula
Fix the kernel-doc comment for drm_sm2fixp(). Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patch.msgid.link/20260615153012.1899576-1-jani.nikula@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2026-06-30drm/dp: fix kernel-doc for struct drm_dp_as_sdpJani Nikula
Add the missing coasting_vtotal kernel-doc member documentation for struct drm_dp_as_sdp. Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patch.msgid.link/20260615153027.1899784-1-jani.nikula@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2026-06-30sched/debug: Remove unused schedstatsShrikanth Hegde
nr_migrations_cold, nr_wakeups_passive and nr_wakeups_idle are not being updated anywhere. So remove them. These are per process stats. So updating sched stats version isn't necessary. Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://patch.msgid.link/20260625124648.802832-2-sshegde@linux.ibm.com
2026-06-30sched/eevdf: Move to a single runqueuePeter Zijlstra (Intel)
Change fair/cgroup to a single runqueue. Infamously fair/cgroup isn't working for a number of people; typically the complaint is latencies and/or overhead. The latency issue is due to the intermediate entries that represent a combination of tasks and thereby obfuscate the runnability of tasks. The approach here is to leave the cgroup hierarchy as is; including the intermediate enqueue/dequeue but move the actual EEVDF runqueue outside. This means things like the shares_weight approximation are fully preserved. That is, given a hierarchy like: R | se--G1 / \ G2--se se--G3 / \ | T1--se se--T2 se--T3 This is fully maintained for load tracking, however the EEVDF parts of cfs_rq/se go unused for the intermediates and are instead connected like: _R_ / | \ T1 T2 T3 Since the effective weight of the entities is determined by the hierarchy, this gets recomputed on enqueue,set_next_task and tick. Notably, the effective weight (se->h_load) is computed from the hierarchical fraction: se->load / cfs_rq->load. Since EEVDF is now exclusively operating on rq->cfs, it needs to consider cfs_rq->h_nr_queued rather than cfs_rq->nr_queued. Similarly, only tasks can get delayed, simplifying some of the cgroup cleanup. One place where additional information was required was set_next_task() / put_prev_task(), where we need to track 'current' both in the hierarchical sense (cfs_rq->h_curr) and in the flat sense (cfs_rq->curr). As a result of only having a single level to pick from, much of the complications in pick_next_task() and preemption go away. Since many of the hierarchical operations are still there, this won't immediately fix the performance issues, but hopefully it will fix some of the latency issues. TODO: split struct cfs_rq / struct sched_entity TODO: try and get rid of h_curr Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260605124052.227463677%40infradead.org
2026-06-30sched/fair: Add cgroup_mode: maxPeter Zijlstra
In order to avoid the average CPU fraction avg(F_g_n) becoming tiny '1/N', assume each cgroup is maximally concurrent and distrubute 'N*weight', such that: F_g_n' = N * F_g_n Giving: avg(F_g_n') = N*avg(F_g_n) ~ N * 1/N = 1 And while this sounds like it solves things, remember what that ~ meant. There is the corner case when a cgroup is minimally loaded, eg a single runnable task, therefore limit the CPU fraction to that of a nice -20 task to avoid getting too much load. This last bit is what makes it different from a previous proposal to allow raising cpu.weight to '100 * N', that would not limit the mininal concurrency case and results in a very large F_g_n. And just like F_g_n << 1 is problematic, so is F_g_n >> 1 for the exact same reasons (it would drown the kthreads, but it also risks overflowing the load values). So while this might appear to be a better scheme than the current default scheme, it doesn't really handle less than maximal concurrency nicely -- it clips and introduces artificially large weights. So where the traditional SMP mode works well when nr_tasks << nr_cpus, MAX doesn't work well in that regime and vice-versa. The meaning of "cpu.weight" would be: weight per allowed CPU. Included for completeness (and infrastructure). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260605124051.589618504%40infradead.org
2026-06-30Merge drm/drm-next into drm-misc-nextThomas Zimmermann
Backmerging to get drm-misc-next to v7.2-rc1. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
2026-06-29drm/edid: parse panel type from DisplayID 2.x Display ParametersChenyu Chen
Parse the Display Parameters Data Block (tag 0x21) defined in DisplayID v2.1a Section 4.2.6. Extract the Display Device Technology field from the color depth and device technology byte, which indicates whether the panel uses LCD or OLED technology. Add a panel_type field to struct drm_display_info and populate it during DisplayID iteration so downstream drivers can use it for panel-type-dependent behavior. Add DRM_MODE_PANEL_TYPE_LCD to the UAPI panel type property alongside the existing OLED value. Assisted-by: Copilot:Claude-Opus-4.6 Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org> Link: https://patch.msgid.link/20260526030254.1460480-3-chen-yu.chen@amd.com Signed-off-by: Mario Limonciello <superm1@kernel.org>
2026-06-29EDAC/debugfs: Remove the fake_inject debugfs interfaceYazen Ghannam
The interface has a potential race condition between a real and fake error when updating the memory controller's error descriptor. There doesn't seem to be an active user base for this interface, so remove it. Closes: https://sashiko.dev/#/patchset/20260518160716.171578-1-yazen.ghannam%40amd.com Reported-by: sashiko-bot <sashiko-bot@kernel.org> Suggested-by: Borislav Petkov <bp@alien8.de> Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/linux-edac/20260611012336.GHaioOGB0NBxv5BZXS@fat_crate.local
2026-06-29tcp: restore RCU grace period in tcp_ao_destroy_sockMichael Bommarito
Commit 51e547e8c89c ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU") removed the call_rcu() callback from tcp_ao_destroy_sock(), arguing that "the destruction of info/keys is delayed until the socket destructor" and therefore "no one can discover it anymore". That argument does not hold for the call site in tcp_connect() (net/ipv4/tcp_output.c:4327-4332). At that point the socket is in TCP_SYN_SENT, has already been inserted into the inet ehash by inet_hash_connect() in tcp_v4_connect(), and is therefore very much discoverable: any softirq running tcp_v4_rcv() on another CPU can take the socket out of the ehash, walk into tcp_inbound_hash(), and load tp->ao_info via implicit RCU before bh_lock_sock_nested() is taken on the destroying CPU. The reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208) which re-loads tp->ao_info via rcu_dereference_check(); the re-load can still observe the (about-to-be-freed) pointer because there is no synchronize_rcu() between rcu_assign_pointer(tp->ao_info, NULL) and tcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is then walked at line 223: hlist_for_each_entry_rcu(key, &ao->head, node, ...) The writer's synchronous kfree() is free to complete between the line 218 re-fetch and the line 223 hlist iteration. The slab is reused (or simply LIST_POISON1-stamped if not yet reused) and the iteration walks attacker-controlled or poison memory in softirq context. Reproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM): an unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET installs TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged TCP-AO segments toward its eventual 4-tuple via raw sockets, then calls connect(). The md5-wins reconciliation in tcp_connect() fires tcp_ao_destroy_sock(); the softirq backlog reader on the loopback NAPI path crashes on the freed ao->head.first walk: Oops: general protection fault, probably for non-canonical address 0xfbd59c000000002f KASAN: maybe wild-memory-access in range [0xdead000000000178-0xdead00000000017f] CPU: 0 UID: 1000 PID: 100 Comm: repro_userns RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0 Call Trace: <IRQ> __tcp_ao_do_lookup+0x107/0x1c0 tcp_ao_inbound_lookup.constprop.0+0x12a/0x200 tcp_inbound_ao_hash+0x5ea/0x1520 tcp_inbound_hash+0x7ce/0x1240 tcp_v4_rcv+0x1e7a/0x3e10 ... Restore the RCU grace period: re-add struct rcu_head to tcp_ao_info and replace the synchronous tcp_ao_info_free() with a call_rcu() callback. Readers that captured tp->ao_info before rcu_assign_pointer NULLed it now see the object remain valid until rcu_read_unlock(). With the patch applied the reproducer runs cleanly for 2000 iterations on the same kernel build. Fixes: 51e547e8c89c ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU") Cc: stable@vger.kernel.org # v6.18+ Reviewed-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Link: https://patch.msgid.link/20260625-tcp-md5-connect-v3-1-1fd313d6c1e0@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-30iio: core: add decimal value formatting into 64-bit valueRodrigo Alencar
Create new format types for iio values (IIO_VAL_DECIMAL64_*), which defines the representation of fixed decimal point values into a single 64-bit number. This new format increases the range of represented values, allowing for integer parts greater than 2^32, as bits are not "wasted" in the fractional part, which can be seen in IIO_VAL_INT_PLUS_MICRO and IIO_VAL_INT_PLUS_NANO. Helpers are created to compose and decompose 64-bit decimals into integer values used in IIO formatting interfaces, which creates consistency and avoid error-prone manual assignments when using wordpart macros. When doing the parsing, kstrtodec64() is used with the scale defined by the specific decimal format type. Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com> Reviewed-by: Nuno Sá <nuno.sa@analog.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-06-30lib: math: div64: add div64_s64_rem()Rodrigo Alencar
Add div64_s64_rem() function, with 32-bit implementation that uses div64_u64_rem() and a branchless approach to resolve the sign of the remainder and quotient (negation in two's complement). Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-06-30lib: kstrtox: add kstrtoudec64() and kstrtodec64()Rodrigo Alencar
Add helpers that parses decimal numbers into 64-bit number, i.e., decimal point numbers with pre-defined scale are parsed into a 64-bit value (fixed precision). After the decimal point, digits beyond the specified scale are ignored. Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-06-29HID: sensor-hub: Add sensor_hub_input_attr_read_values() for multi-byte readsSrinivas Pandruvada
sensor_hub_input_attr_get_raw_value() is limited to returning a single 32-bit value, which is insufficient for sensors that report data larger than 32 bits, such as a quaternion with four s16 elements. Add sensor_hub_input_attr_read_values() that accepts a caller-provided buffer and accumulates incoming data until the buffer is full. The two paths are distinguished in sensor_hub_raw_event() by pending.max_raw_size being non-zero, preserving backward compatibility. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Co-developed-by: Zhang Lixu <lixu.zhang@intel.com> Signed-off-by: Zhang Lixu <lixu.zhang@intel.com> Acked-by: Jiri Kosina <jkosina@suse.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2026-06-29clk: add clk_determine_rate_noop()Brian Masney
Add a new helper clk_determine_rate_noop() that's for clocks where the rate rounding is handled by the firmware/hardware, or the clock is capable of any rate. The requested rate is passed through unchanged, and the actual rate will be learned via recalc_rate() after the rate is set. This shared helper will be used to get rid of the driver-specific empty determine rate implementations that are present in the tree. Signed-off-by: Brian Masney <bmasney@redhat.com>
2026-06-29clk: add kernel docs for the core flagsBrian Masney
Let's add a DOC section for the clk core flags, and move the documentation for each flag into the doc header so that it can be easily referenced in the generated kernel documentation. Note: The comment about "Please update clk_flags..." is included as a separate comment so it doesn't show up in the generated documents. Reviewed-by: Maxime Ripard <mripard@kernel.org> Signed-off-by: Brian Masney <bmasney@redhat.com>
2026-06-29kunit,rust: Add ability to skip entire test suitesVaibhav Jain
Currently, KUnit provides mechanisms to skip individual test cases, but there is no way to skip an entire test suite based on runtime conditions checked during suite initialization. This limitation forces test suites to either fail or skip tests individually when certain prerequisites are not available. To address this limitation, the patch adds a 'status' field to struct kunit_suite that allows suite_init callbacks to mark the entire suite as KUNIT_SKIPPED. When a suite is marked as skipped, all test cases within that suite are bypassed without execution. The patch proposed changes to kunit_suite_has_succeeded() to Check suite status before evaluating individual test case results. Also kunit_run_tests() is updated to skip suite execution if kunit_suite's 'status' is KUNIT_SKIPPED, thats either set before suite_init or by the suite_init callback itself. kunit_init_suite() is updated to initialize the 'status' of kunit_suite to KUNIT_SUCCESS so that any skipped suite's can be restarted from debugfs. This enables test suites to perform runtime capability checks in their 'suite_init' callback and gracefully skip all tests when prerequisites are not met, rather than reporting failures or requiring each test case to perform redundant checks. In case a kunit-suite is skipped it can be re-run from the kunit's debugfs interface. Also update debugfs_print_results() to clearly log the kunit-suite as 'SKIP'. kunit_suite_has_succeeded() is also updated on which debugfs_print_results() depends to update 'kunit_suite.status' in case any of the kunit_case has failed. Finally, update KUnit Rust binding macro-rule 'kunit_unsafe_test_suite' to add and initialize the newly introduced 'kunit_suite.status'. Without this 'kunit_suite.status' field is never initialized which is an error for the Rust compiler. Link: https://patchwork.kernel.org/project/linux-kselftest/patch/20260626085811.151133-2-vaibhav@linux.ibm.com/mbox/ Reviewed-by: David Gow <david@davidgow.net> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-06-29vfio/pci: Latch all module parameters per deviceAlex Williamson
The vfio-pci module parameters of disable_idle_d3, nointxmask, and disable_vga latch vfio-pci policy into vfio-pci-core globals each time the vfio-pci module is initialized. The disable_idle_d3 parameter has already migrated to a per-device flag in order to provide consistency for refcounted PM operations for the lifetime of the device registration. Pull the remaining vfio-pci module-parameter policy out of vfio-pci-core into per-device flags set at device initialization. This also restores the mutable aspect of the disable_idle_d3 and nointxmask module parameters for vfio-pci, with the caveat that the parameters are latched into the device at probe. A notable change for variant drivers is that their devices are no longer affected by vfio-pci module parameters and those drivers may need to adopt similar module parameters if any devices have a hidden dependency on vfio-pci setting non-default policy. Assisted-by: Claude:claude-opus-4-8 Acked-by: Chengwen Feng <fengchengwen@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20260615191241.688297-6-alex.williamson@nvidia.com Signed-off-by: Alex Williamson <alex@shazbot.org>
2026-06-29vfio/pci: Fix racy bitfields and tighten struct layoutAlex Williamson
Bitfield operations are not atomic, they use a read-modify-write pattern, therefore we should be careful not to pack bitfields that can be concurrently updated into the same storage unit. This split takes a binary approach: flags that are only modified pre/post open/close remain bitfields, flags modified from user action, including actions that reach across to another device (ex. reset) use dedicated storage units. Note that the virq_disabled and bardirty flags are relocated to fill an existing hole in the structure. Bitfield justifications: has_dyn_msix: written only in vfio_pci_core_enable() pci_2_3: written only in vfio_pci_core_enable() reset_works: written only in vfio_pci_core_enable() extended_caps: written only in vfio_cap_len() under vfio_config_init() has_vga: written only in vfio_pci_core_enable() nointx: written only in vfio_pci_core_enable() needs_pm_restore: written only in vfio_pci_probe_power_state() disable_idle_d3: written only at .init in vfio_pci_core_init_dev() Dedicated storage units: virq_disabled: written by guest INTx command writes in vfio_basic_config_write() while the device is open bardirty: written by guest BAR writes in vfio_basic_config_write() while the device is open pm_intx_masked: written in the runtime-PM suspend path. pm_runtime_engaged: written by low-power feature entry/exit paths needs_reset: set in vfio_pci_core_disable() and cleared for devices in the set by vfio_pci_dev_set_try_reset() sriov_active: written by vfio_pci_core_sriov_configure() via sysfs sriov_numvfs while bound. Fixes: 9cd0f6d5cbb6 ("vfio/pci: Use bitfield for struct vfio_pci_core_device flags") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Alex Williamson <alex.williamson@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20260615191241.688297-4-alex.williamson@nvidia.com Signed-off-by: Alex Williamson <alex@shazbot.org>
2026-06-29vfio/pci: Latch disable_idle_d3 per deviceAlex Williamson
When disable_idle_d3 was introduced in vfio-pci, it directly manipulated the device power state with pci_set_power_state(). There were no refcounts to maintain or balanced operations, we could unconditionally bring the device to D0 and conditionally move it to D3hot. Therefore the module parameter was made writable. Later, in commit c61302aa48f7 ("vfio/pci: Move module parameters to vfio_pci.c"), as part of the vfio-pci-core split, the writable aspect of the module parameter was nullified. The parameter value could still be changed through sysfs, but the vfio-pci driver latched the values into vfio-pci-core globals at module init. Loading the vfio-pci module, or unloading and reloading, with non-default or different values could change the globals relative to existing devices bound to vfio-pci variant drivers. Runtime PM was introduced in commit 7ab5e10eda02 ("vfio/pci: Move the unused device into low power state with runtime PM"), which marks the point where power states became refcounted. PM get and put operations need to be balanced, but the same module operations noted above can change the global variables relative to those devices already bound to vfio-pci variant drivers. This introduces a window where PM operations can now become unbalanced. To resolve this with a narrow footprint for stable backports, the disable_idle_d3 flag is latched into the vfio_pci_core_device at the time of initialization, such that the device always operates with a consistent value. NB. vfio_pci_dev_set_try_reset() now unconditionally raises the runtime PM usage count around bus reset to account for disable_idle_d3 becoming a per-device rather than global flag. When this flag is set, the additional get/put pair is harmless and allows continued use of the shared vfio_pci_dev_set_pm_runtime_get() helper. Fixes: 7ab5e10eda02 ("vfio/pci: Move the unused device into low power state with runtime PM") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Alex Williamson <alex.williamson@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20260615191241.688297-2-alex.williamson@nvidia.com Signed-off-by: Alex Williamson <alex@shazbot.org>
2026-06-29regulator: max14577: fix set_mode clobbering enable on MAX77836 LDOsJad Keskes
So the PWRMD field in CNFG1_LDO is both the enable bit and the mode. You can't change one without stepping on the other. The problem is that enable() from the regulator core just writes enable_mask (which is PWRMD_NORMAL). If you'd called set_mode(LPM) then disabled and re-enabled, the mode gets reset to NORMAL. And set_mode updates the register through the same field, so it can accidentally enable a disabled regulator. Fix it by storing the mode in per-regulator data. A custom enable writes whatever mode was last set. set_mode only touches hardware if the regulator is already on; otherwise it just caches the value. Add of_map_mode while here so the initial mode can be wired from DT. Signed-off-by: Jad Keskes <inasj268@gmail.com> Acked-by: Lee Jones <lee@kernel.org> Link: https://patch.msgid.link/20260617094622.1846471-1-inasj268@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2026-06-29cxl: Support dpa without a mailboxAlejandro Lucero
Type3 relies on mailbox CXL_MBOX_OP_IDENTIFY command for initializing memdev state params which end up being used for DPA initialization. Allow a Type2 driver to initialize DPA simply by giving the size of its volatile hardware partition. Move related functions to memdev. Signed-off-by: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Acked-by: Edward Cree <ecree.xilinx@gmail.com> Link: https://patch.msgid.link/20260629183727.51502-3-alejandro.lucero-palau@amd.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-06-29cxl: Support Type2 cxl regs mappingAlejandro Lucero
Export cxl core functions for a Type2 driver being able to discover and map the device registers. Signed-off-by: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com> Acked-by: Edward Cree <ecree.xilinx@gmail.com> Link: https://patch.msgid.link/20260629183727.51502-2-alejandro.lucero-palau@amd.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-06-29ASoC: SOF: add Intel UAOL sof_ipc_dai_typeBard Liao
The type will be used for Intel USB Audio Offload Link (UAOL) DAI. Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com> Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com> Link: https://patch.msgid.link/20260615134439.1044872-1-yung-chuan.liao@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
2026-06-29dt-bindings: clock: Add ESWIN eic7700 HSP clock and reset generatorXuyang Dong
Add bindings for the high-speed peripherals clock and reset generator on the ESWIN EIC7700 HSP. Acked-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Xuyang Dong <dongxuyang@eswincomputing.com> Signed-off-by: Brian Masney <bmasney@redhat.com>
2026-06-29clk: Introduce clk_hw_set_spread_spectrumPeng Fan
Add clk_hw_set_spread_spectrum to configure a clock to enable spread spectrum feature. set_spread_spectrum ops is added for clk drivers to have their own hardware specific implementation. Reviewed-by: Brian Masney <bmasney@redhat.com> Reviewed-by: Sebin Francis <sebin.francis@ti.com> Signed-off-by: Peng Fan <peng.fan@nxp.com> Signed-off-by: Brian Masney <bmasney@redhat.com>
2026-06-29dt-bindings: clock: Add spread spectrum definitionPeng Fan
Per dt-schema, the modulation methods are: down-spread(3), up-spread(2), center-spread(1), no-spread(0). So define them in dt-bindings to avoid write the magic number in device tree. Reviewed-by: Brian Masney <bmasney@redhat.com> Acked-by: Rob Herring (Arm) <robh@kernel.org> Reviewed-by: Sebin Francis <sebin.francis@ti.com> Signed-off-by: Peng Fan <peng.fan@nxp.com> Signed-off-by: Brian Masney <bmasney@redhat.com>
2026-06-29remoteproc: xlnx: Refactor start & stop opsTanmay Shah
Current _start and _stop ops are implemented using various APIs from the platform management firmware driver. Instead provide respective RPU start and stop API in the firmware driver and move the logic to interact with the PM firmware in the firmware driver. The remoteproc driver doesn't need to know actual logic, but only the final result i.e. RPU start/stop was success or not. This refactor keeps the remoteproc driver simple and moves firmware interaction logic to the firmware driver. Signed-off-by: Tanmay Shah <tanmay.shah@amd.com> Acked-by: Michal Simek <michal.simek@amd.com> Link: https://lore.kernel.org/r/20260619163854.410392-1-tanmay.shah@amd.com Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2026-06-29mtd: spinand: add support for HeYangTek HYF1GQ4UDACAEAleksei Sviridkin
The HeYangTek HYF1GQ4UDACAE is a 1 Gbit (128 MiB) SLC SPI-NAND with 2048 + 64 byte pages and on-die 4-bit / 512-byte ECC; its JEDEC manufacturer ID is 0xc9. The die is GD5F1GQ4-compatible, so the OOB layout is taken from the in-tree gd5fxgq4xa. The die exposes only a coarse 2-bit ECC status with no fine-grained bitflip-count register, so the status is decoded into a representative number of corrected bitflips. It is found, among others, on some Keenetic KN-3411 (Buddy 6) units. Datasheet: https://www.heyangtek.cn/previewfile.jsp?file=ABUIABA9GAAgwsvRnwYo-eDpsgc Signed-off-by: Aleksei Sviridkin <f@lex.la> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2026-06-29vdso: Replace __ASSEMBLY__ with __ASSEMBLER__ in header filesThomas Huth
While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So standardize now on the __ASSEMBLER__ macro that is provided by the compilers. Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://patch.msgid.link/20260619100600.121042-1-thuth@redhat.com
2026-06-29firmware: stratix10-rsu: Add flash device info retrieval via SMCTze Yee Ng
Extend the Intel Remote System Update (RSU) driver to retrieve the device info table through an ARM SMC call to the service layer. The table reports flash size and erase size for multiple devices. Signed-off-by: Tze Yee Ng <tze.yee.ng@altera.com> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
2026-06-29ALSA: hda: Force resume if acomp notified during system suspendNícolas F. R. A. Prado
Currently if an HDMI cable is connected while the system is suspended, the HDMI audio jack status stays off after resume. This is due to the jack state not being synced by the HDA HDMI codec device's runtime resume, as that never happens if the device was runtime suspended before the system suspended, or by the acomp notification triggered from the DRM side if that happens before the HDA HDMI codec device has resumed. To fix this, if snd_hda_hdmi_acomp_pin_eld_notify() gets called before the HDA HDMI codec device has resumed, mark it to be forcefully runtime resumed at the next PM complete time. Do this using a separate acomp_requested_resume flag that can be temporarily set without overwriting forced_resume for drivers that always want to force resume. Assisted-by: Copilot:claude-sonnet-4.6 Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Link: https://patch.msgid.link/20260626-hda-force-resume-eld-notify-v1-1-a92cb01393e0@collabora.com Signed-off-by: Takashi Iwai <tiwai@suse.de>
2026-06-29ARM: s3c: Replace __ASSEMBLY__ with __ASSEMBLER__ in header filesThomas Huth
While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with uapi headers that rather should use __ASSEMBLER__ instead. So let's standardize now on the __ASSEMBLER__ macro that is provided by the compilers. This is a completely mechanical patch (done with a simple "sed -i" statement). Signed-off-by: Thomas Huth <thuth@redhat.com> Link: https://patch.msgid.link/20260619125827.215977-1-thuth@redhat.com Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-06-29dt-bindings: clock: Add Amlogic A9 AO clock controllerJian Hu
Add the Always-On clock controller dt-bindings for the Amlogic A9 SoC family. Acked-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Jian Hu <jian.hu@amlogic.com> Link: https://patch.msgid.link/20260623-a9_aoclk-v5-1-c7cb1ff9ebf1@amlogic.com Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
2026-06-29fs: add umh argument to struct kernel_clone_argsChristian Brauner
Add a umh field to struct kernel_clone_args. When set, copy_fs() copies from pid 1's fs_struct instead of the kthread's fs_struct. This ensures usermodehelper threads always get init's filesystem state regardless of their parent's (kthreadd's) fs. Usermodehelper threads are not allowed to create mount namespaces (CLONE_NEWNS), share filesystem state (CLONE_FS), or be started from a non-initial mount namespace. No usermodehelper currently does this so we don't need to worry about this restriction. Set .umh = 1 in user_mode_thread(). At this stage pid 1's fs points to rootfs which is the same as kthreadd's fs, so this is functionally equivalent. Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-20-77ee053060e0@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: make userspace_init_fs a dynamically-initialized pointerChristian Brauner
Change userspace_init_fs from a declared-but-unused extern struct to a dynamically initialized pointer. Add init_userspace_fs() which is called early in kernel_init() (PID 1) to record PID 1's fs_struct as the canonical userspace filesystem state. Wire up __override_init_fs() and __revert_init_fs() to actually swap current->fs to/from userspace_init_fs. Previously these were no-ops that stored current->fs back to itself. Fix nullfs_userspace_init() to compare against userspace_init_fs instead of &init_fs. When PID 1 unshares its filesystem state, revert userspace_init_fs to init_fs's root (nullfs) so that stale filesystem state is not silently inherited by kworkers and usermodehelpers. At this stage PID 1's fs still points to rootfs (set by init_mount_tree), so userspace_init_fs points to rootfs and scoped_with_init_fs() is functionally equivalent to its previous no-op behavior. Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-5-77ee053060e0@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: add real_fs to track task's actual fs_structChristian Brauner
Add a real_fs field to task_struct that always mirrors the fs field. This lays the groundwork for distinguishing between a task's permanent fs_struct and one that is temporarily overridden via scoped_with_init_fs(). When a kthread temporarily overrides current->fs for path lookup, we need to know the original fs_struct for operations like exit_fs() and unshare_fs_struct() that must operate on the real, permanent fs. For now real_fs is always equal to fs. It is maintained alongside fs in all the relevant paths: exit_fs(), unshare_fs_struct(), switch_fs_struct(), and copy_fs(). Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-4-77ee053060e0@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: add scoped_with_init_fs()Christian Brauner
Similar to scoped_with_kernel_creds() allow a temporary override of current->fs to serve the few places where lookup is performed from kthread context or needs init's filesytem state. Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-3-77ee053060e0@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: add switch_fs_struct()Christian Brauner
Don't open-code the guts of replacing current's fs struct. Link: https://patch.msgid.link/20260601-work-kthread-nullfs-v4-1-77ee053060e0@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29super: make fs_holder_ops privateChristian Brauner
Now that filesystems open and claim their block devices through fs_bdev_file_open_by_{dev,path}(), nothing outside fs/super.c references fs_holder_ops. Make it static and drop its declaration from blkdev.h. Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-16-7df6b864028e@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: look up superblocks via the device table in fs_holder_opsChristian Brauner
Switch the fs_holder_ops callbacks from recovering the single owning superblock out of bdev->bd_holder to walking the device-to-superblock table and acting on every superblock registered for the device. The holder argument becomes purely the block layer's exclusivity token and is no longer needed by the fs specific callbacks. All devices opened with fs_holder_ops are registered by now: the main device since setup_bdev_super() switched to fs_bdev_file_open_by_dev() and the extra devices (xfs log and realtime devices, btrfs member devices, the ext4 external journal) since the preceding per-filesystem conversions. So no event is lost in the switchover. The walk uses a refcount-pinning cursor: each step takes a reference on the entry via sd_ref and resumes from its sd_node. Unlinking an entry is deferred to the last unpin, so a cursor never resumes from a removed node. mark_dead and sync only need the passive reference the entry holds plus s_umount, which they take with super_lock_shared(). freeze and thaw additionally need an active reference and acquire it with get_active_super(), which waits for the superblock to be born before taking s_active. Taking s_active before the superblock is born would pin a still-mounting superblock so a racing mount that aborts could never drop s_active to zero and reach SB_DYING, deadlocking the wait for SB_BORN. This is how filesystems_freeze() and filesystems_thaw() acquire it too. One semantic change: when no live superblock uses the device anymore (the holder is dying or was never registered), fs_bdev_freeze() and fs_bdev_thaw() now return 0 - freeze after syncing the block device - where they used to return -EINVAL. The freeze-deny release path moves to the table in the same switchover. A device made unfreezable for a btrfs membership change must drop its table entry before re-allowing freezing; otherwise a freeze racing the release reaches the superblock through the still-registered entry and is stranded once the release unlinks it. Split fs_bdev_unregister() out of fs_bdev_file_release() - the inverse of fs_bdev_register() - so btrfs_release_device_allow_freeze() can drop the {dev, sb} entry, re-allow freezing on the still-open device, then close it. Re-allowing only after the entry is gone keeps a racing freeze from reaching the superblock, and doing it while the file is still open avoids touching the block device after the close. btrfs previously yielded bd_holder before re-allowing, which this commit makes irrelevant to freeze resolution. Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-12-7df6b864028e@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: add dedicated block device open helpers for filesystemsChristian Brauner
Add fs_bdev_file_open_by_{dev,path}() and fs_bdev_file_release(). They open the device with fs_holder_ops and register a claim in the device-to-superblock table. Claims on the same (device, superblock) pair share one entry, so when a filesystem claims a device it already uses (xfs with its log on the data device), no second entry is added and each superblock will be acted on once. The holder argument remains purely the block layer's exclusivity token: a superblock, or a file_system_type for a device shared by several superblocks of that type. The shared case only becomes usable once the fs_holder_ops callbacks resolve superblocks through the table instead of bdev->bd_holder. Convert the main device, setup_bdev_super() and kill_block_super(), over: the open finds the entry registered by sget_fc() and claims it again. cramfs and romfs bypass kill_block_super() so they can handle MTD mounts and release the main device with a plain bdev_fput(), which would leave the claim behind: the (dev, sb) entry would never be unregistered and the passive reference it holds would keep the superblock alive forever. Convert their release paths in the same step. The frozen-device check stays in setup_bdev_super() for the primary device and is added to fs_bdev_register() for new claims, i.e. every additional device a filesystem opens through the helpers. Only a (device, superblock) pair the superblock claimed earlier may be reopened while frozen (xfs with its log on the data device): the freeze already covers that superblock through the existing claim, so nothing escapes it. Without the setup_bdev_super() check a device frozen before the mount even started (dm lock_fs, loop) could be mounted and written to (journal replay) under an active freeze, because the primary open reuses the entry registered by sget_fc() and never takes the new-claim path. Both checks read bd_fsfreeze_count only after the entry is published (by sget_fc() for the primary, by fs_bdev_register() for new claims) and pair with bdev_freeze() incrementing the count before walking the table: either the mount sees the elevated freeze count and fails with EBUSY, or the freeze finds the published entry and converges once SB_BORN is set. Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-8-7df6b864028e@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: maintain a global device-to-superblock tableChristian Brauner
fs_holder_ops recovers the owning superblock from bdev->bd_holder, which forces the holder to be exactly one superblock and prevents several superblocks from sharing one block device. That's what erofs is doing. As a first step introduce a global dev_t-keyed rhltable mapping each device to the superblock(s) using it. The entry is preallocated in alloc_super() and registered under sb->s_dev by the set callback through set_anon_super() and set_bdev_super(), the two helpers every set callback assigns s_dev through. Registration is the final fallible act of a set callback, so an insert failure unwinds through sget_fc()'s existing set-failure path: the fs_context keeps ownership of s_fs_info and the callers' error paths stay correct. set_anon_super() releases the anonymous dev it allocated when registration fails. Unwinding through deactivate_locked_super() instead would run kill_sb() and free s_fs_info behind the caller's back: nfs and ceph free that object through a local pointer when sget_fc() fails and would double-free. The superblock stashes the entry in sb->s_super_dev and kill_super_notify() drops the claim through it, so teardown doesn't depend on s_dev staying stable; an entry that was never registered is freed together with the superblock in destroy_super_work(). Each table entry holds a passive reference (s_passive) on its superblock, so the struct stays valid for as long as the entry is reachable. Entries are claim-counted through sd_ref: additional claims on the same (device, superblock) pair share the entry, and the unlink is deferred to the last put, so a later iteration cursor never resumes from a removed node. The table is initialized from mnt_init(): the first superblocks (the tmpfs shm mount and rootfs) are created from start_kernel() long before any initcall runs, so an initcall would be too late. The table has no readers yet; the fs_holder_ops callbacks are switched over once all devices a filesystem claims are registered. Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-7-7df6b864028e@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs, block: move blk_mode_t and fop_flags_t into <linux/types.h>Christian Brauner
blk_mode_t and fop_flags_t are both plain 'unsigned int __bitwise' flag typedefs, exactly like the gfp_t, slab_flags_t and fmode_t that already live in <linux/types.h>. Move them there so they are available everywhere without having to drag in a subsystem header. Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-4-7df6b864028e@kernel.org Tested-by: syzbot@syzkaller.appspotmail.com Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29super: convert s_count to refcount_t s_passiveChristian Brauner
The superblock carries two counters: s_active, the active reference count that keeps the filesystem usable, and s_count, the passive reference count that merely keeps the structure itself alive. Turn the passive count into a refcount_t and rename it to s_passive to make the pairing with s_active obvious. Everything is still serialized by sb_lock, so there is no functional change; the conversion buys the usual refcount_t saturation and underflow checking. The following patches start dropping passive references without holding sb_lock and make the device-to-superblock table hold one passive reference per registered entry, which a plain integer cannot support. Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-2-7df6b864028e@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29block: split bdev_yield_claim() out of bdev_fput()Christian Brauner
bdev_fput() yields the holder claim and then closes the file, which is a deferred operation. Split the yield half into bdev_yield_claim() so a caller can give up the holder while the file - and therefore the block device - is still open, act on the device, and only then bdev_fput(). A filesystem that made a device unfreezable for a membership change with bdev_deny_freeze() undoes the deny on release with bdev_yield_claim(bdev_file); bdev_allow_freeze(file_bdev(bdev_file)); bdev_fput(bdev_file); Re-allowing only after the holder is yielded avoids stranding the filesystem on a racing freeze, and doing it while the file is still open avoids touching the block device after bdev_fput(). bdev_fput() yields again, which is a no-op once the claim has already been given up. Link: https://patch.msgid.link/20260616-work-super-freeze_deny_upstream-v2-2-b3567c7f994b@kernel.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewd-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29block: allow making a block device unfreezableChristian Brauner
Add bdev_deny_freeze() and bdev_allow_freeze(), modeled on deny_write_access()/allow_write_access(). bd_fsfreeze_count becomes a signed counter: > 0 counts active freezes, < 0 counts deniers, and the two regimes are mutually exclusive. bdev_freeze() refuses with -EBUSY while a deny is held, and bdev_deny_freeze() refuses while the device is frozen. A filesystem that mutates a device's membership (a btrfs device add, remove or replace) denies freezing on the device for the duration, so a claim a freeze walk might act on is never added or torn down behind the freezer's back. The deny/allow helpers are a single atomic on bd_fsfreeze_count and take no lock, so they can be called while holding s_umount without inverting against bdev_freeze()'s bd_fsfreeze_mutex -> s_umount order. Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/20260616-work-super-freeze_deny_upstream-v2-1-b3567c7f994b@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-29fs: Add bpf_sock_read_xattr() kfunc to read socket xattrsChristian Brauner
In c8db08110cbe ("Merge tag 'vfs-7.1-rc1.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs") we added support for extended attributes for sockets. This comes in two flavors: sockfs and non-sockfs/filesystem sockets. Filesystem sockets are actual filesystem objects so reading xattrs must use dedicated fs helpers such as bpf_get_dentry_xattr() and bpf_get_file_xattr(). Those are inherently sleeping operations. Sockfs sockets on the other hand don't need to use sleeping operations as the underlying data structure is lockless. In addition, retrieval of sockfs extended attributes often happens from LSM hooks that only provide struct socket and it's completely nonsensical to grab a reference to a file, then force a sleeping operation to retrieve the xattr and drop the reference. We know that the sockfs file cannot go away while the LSM hook runs. This series adds a bpf_sock_read_xattr() kfunc that, given a struct socket, reads a user.* extended attribute from the socket's sockfs inode into a bpf_dynptr. Together with fsetxattr() from userspace this lets a process label a socket with a user.* xattr and have a BPF LSM program retrieve that label locklessly. The kfunc mirrors the existing bpf_cgroup_read_xattr(), including the restriction to the user.* namespace. systemd uses user.* xattrs on sockets to implement socket rate limiting and to tag sockets for other purposes [1] such as implementing a varlink registry. There is currently no efficient way for a BPF program to read those labels back. The new helper allows a listening socket marked with an extended attribute to be read back during bind/connect and then act on the connect()ing socket. Extended attributes make it possible to allow an unprivileged user manager such as systemd --user to mark sockets from userspace and then rediscover them or implement policies. The kfunc is registered KF_RCU and only for BPF LSM programs. A struct socket is only guaranteed to live in sockfs when an LSM socket hook hands it out, which is what keeps SOCK_INODE() valid. Sockets that embed struct socket outside sockfs (tun, tap) are only reachable from tracing programs and are excluded by the registration. (Btw, for consistency it would be nice to force allocation of struct socket from sockfs instead of simply embedding it in e.g., struct tun_file which makes the SOCKFS_I() pattern a hazard - at least outside of sockfs functions.) The read never sleeps and takes no lock. For sockfs the value lives in the inode's in-memory xattr store and simple_xattr_get() resolves it with an RCU-protected rhashtable lookup, taking neither the inode lock nor any xattr lock. The kfunc is therefore usable from both sleepable and non-sleepable LSM hooks. Link: https://github.com/systemd/systemd/pull/40559 [1] Link: https://patch.msgid.link/20260617-work-bpf-sock-xattr-v1-1-a1276f7c9da3@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>