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2026-06-15Merge tag 'driver-core-7.2-rc1' of ↵Linus Torvalds
gitolite.kernel.org:pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "Deferred probe: - Fix race where deferred probe timeout work could be permanently canceled by using mod_delayed_work() - Fix missing jiffies conversion in deferred_probe_extend_timeout() - Guard timeout extension with delayed_work_pending() to prevent premature firing - Use system_percpu_wq instead of the deprecated system_wq - Update deferred_probe_timeout documentation device: - Replace direct struct device bitfield access (can_match, dma_iommu, dma_skip_sync, dma_ops_bypass, state_synced, dma_coherent, of_node_reused, offline, offline_disabled) with flag-based accessors using bit operations - Reject devices with unregistered buses - Delete unused DEVICE_ATTR_PREALLOC() - Add low-level device attribute macros with const show/store callbacks, allowing device attributes to reside in read-only memory - Move core device attributes to read-only memory - Constify group array pointers in driver_add_groups() / driver_remove_groups(), struct bus_type, and struct device_driver device property: - Fix fwnode reference leak in fwnode_graph_get_endpoint_by_id() - Initialize all fields of fwnode_handle in fwnode_init() - Provide swnode_get()/swnode_put() wrappers around kobject_get/put() - Allow passing struct software_node_ref_args pointers directly to PROPERTY_ENTRY_REF() driver_override: - Migrate amba, cdx, vmbus, and rpmsg to the generic driver_override infrastructure, fixing a UAF from unsynchronized access to driver_override in bus match() callbacks - Remove the now-unused driver_set_override() firmware loader: - Fix recursive lock deadlock in device_cache_fw_images() when async work falls back to synchronous execution - Fix device reference leak in firmware_upload_register() platform: - Pass KBUILD_MODNAME through the platform driver registration macro to create module symlinks in sysfs for built-in drivers; move module_kset initialization to a pure_initcall and tegra cbb registration to core_initcall to ensure correct ordering - Pass THIS_MODULE implicitly through a coresight_init_driver() macro sysfs: - Upgrade OOB write detection in sysfs_kf_seq_show() from printk to WARN - Add return value clamping to sysfs_kf_read() Rust: - ACPI: Fix missing match data for PRP0001 by exporting acpi_of_match_device() - Auxiliary: Replace drvdata() with dedicated registration data on auxiliary_device. drvdata() exposed the driver's bus device private data beyond the driver's own scope, creating ordering constraints and forcing the data to outlive all registrations that access it. Registration data is instead scoped structurally to the Registration object, making lifecycle ordering enforced by construction rather than convention. - Rust-native device driver lifetimes (HRT): Allow Rust device drivers to carry a lifetime parameter on their bus device private data, tied to the device binding scope -- the interval during which a bus device is bound to a driver. Device resources like pci::Bar<'a> and IoMem<'a> can be stored directly in the driver's bus device private data with a lifetime bounded by the binding scope, so the compiler enforces at build time that they do not outlive the binding. This removes Devres indirection from every access site and eliminates try_access() failure paths in destructors. Bus driver traits use a Generic Associated Type (GAT) Data<'bound> to introduce the lifetime on the private data, rather than parameterizing the Driver trait itself. Auxiliary registration data, where the lifetime is not introduced by a trait callback but must be threaded through Registration, uses the ForLt trait (a type-level abstraction for types generic over a lifetime). Misc: - Fix DT overlayed devices not probing by reverting the broken treewide overlay fix and re-running fw_devlink consumer pickup when an overlay is applied to a bound device - Use root_device_register() for faux bus root device; add sanity check for failed bus init - Fix dev_has_sync_state() data race with READ_ONCE() and move it to base.h - Avoid spurious device_links warning when removing a device while its supplier is unbinding - Switch ISA bus to dynamic root device - Fix suspicious RCU usage in kernfs_put() - Remove devcoredump exit callback - Constify devfreq_event_class" * tag 'driver-core-7.2-rc1' of gitolite.kernel.org:pub/scm/linux/kernel/git/driver-core/driver-core: (81 commits) software node: allow passing reference args to PROPERTY_ENTRY_REF() driver core: platform: set mod_name in driver registration coresight: pass THIS_MODULE implicitly through a macro kernel: param: initialize module_kset in a pure_initcall soc/tegra: cbb: Move driver registration from pure_initcall to core_initcall firmware_loader: Fix recursive lock in device_cache_fw_images() driver core: Use system_percpu_wq instead of system_wq driver core: remove driver_set_override() rpmsg: use generic driver_override infrastructure Drivers: hv: vmbus: use generic driver_override infrastructure cdx: use generic driver_override infrastructure amba: use generic driver_override infrastructure rust: devres: add 'static bound to Devres<T> samples: rust: rust_driver_auxiliary: showcase lifetime-bound registration data rust: auxiliary: generalize Registration over ForLt rust: types: add `ForLt` trait for higher-ranked lifetime support gpu: nova-core: separate driver type from driver data samples: rust: rust_driver_pci: use HRT lifetime for Bar rust: io: make IoMem and ExclusiveIoMem lifetime-parameterized rust: pci: make Bar lifetime-parameterized ...
2026-06-15Merge tag 'vfs-7.2-rc1.procfs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull procfs updates from Christian Brauner: - Revamp fs/filesystems.c The file was a mess with a hand-rolled linked list in desperate need of a cleanup. The filesystems list is now RCU-ified, /proc files can be marked permanent from outside fs/proc/, and the string emitted when reading /proc/filesystems is pre-generated and cached instead of pointer-chasing and printfing entry by entry on every read. The file is read frequently because libselinux reads it and is linked into numerous frequently used programs (even ones you would not suspect, like sed!). Scalability also improves since reference maintenance on open/close is bypassed. open+read+close cycle single-threaded (ops/s): before: 442732 after: 1063462 (+140%) open+read+close cycle with 20 processes (ops/s): before: 606177 after: 3300576 (+444%) A follow-up patch adds missing unlocks in some corner cases and tidies things up. - Relax the mount visibility check for subset=pid mounts When procfs is mounted with subset=pid, all static files become unavailable and only the dynamic pid information is accessible. In that case there is no point in imposing the full mount visibility restrictions on the mounter - everything that can be hidden in procfs is already inaccessible. These restrictions prevented procfs from being mounted inside rootless containers since almost all container implementations overmount parts of procfs to hide certain directories. As part of this /proc/self/net is only shown in subset=pid mounts for CAP_NET_ADMIN, reconfiguring subset=pid is rejected, the SB_I_USERNS_VISIBLE superblock flag is replaced with an FS_USERNS_MOUNT_RESTRICTED filesystem flag, fully visible mounts are recorded in a list, and the mount restrictions are finally documented. - Protect ptrace_may_access() with exec_update_lock in procfs Most uses of ptrace_may_access() in procfs should hold exec_update_lock to avoid TOCTOU issues with concurrent privileged execve() (like setuid binary execution). This fixes the easy cases - the owner and visibility checks and the FD link permission checks - with the gnarlier ones to follow later. * tag 'vfs-7.2-rc1.procfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: fix ups and tidy ups to /proc/filesystems caching proc: protect ptrace_may_access() with exec_update_lock (FD links) proc: protect ptrace_may_access() with exec_update_lock (part 1) docs: proc: add documentation about mount restrictions proc: handle subset=pid separately in userns visibility checks proc: prevent reconfiguring subset=pid proc: subset=pid: Show /proc/self/net only for CAP_NET_ADMIN fs: cache the string generated by reading /proc/filesystems sysfs: remove trivial sysfs_get_tree() wrapper fs: RCU-ify filesystems list fs: move SB_I_USERNS_VISIBLE to FS_USERNS_MOUNT_RESTRICTED proc: allow to mark /proc files permanent outside of fs/proc/ namespace: record fully visible mounts in list
2026-05-25Merge tag 'v7.1-rc5' into driver-core-nextDanilo Krummrich
We need the driver-core fixes in here as well to build on top of. Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-05-20sysfs: clamp show() return value in sysfs_kf_read()Greg Kroah-Hartman
sysfs_kf_seq_show() defends against buggy show() callbacks that return larger than PAGE_SIZE by clamping the value and printing a warning. sysfs_kf_read(), the prealloc variant, has no such defense. The only current in-tree user of __ATTR_PREALLOC is drivers/md/md.c, whose show() callbacks are well-behaved, so this is hardening against future drivers doing foolish things and out-of-tree code doing even more foolish things. Cc: NeilBrown <neil@brown.name> Cc: Tejun Heo <tj@kernel.org> Fixes: 2b75869bba67 ("sysfs/kernfs: allow attributes to request write buffer be pre-allocated.") Assisted-by: gregkh_clanker_t1000 Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Link: https://patch.msgid.link/2026052000-drove-unicycle-d61b@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-20sysfs: don't remove existing directory on update failureGreg Kroah-Hartman
When sysfs_update_group() is called for a named group and create_files() fails (e.g. -ENOMEM), internal_create_group() calls kernfs_remove(kn) on the group directory. In the update path, kn was obtained via kernfs_find_and_get() and refers to a directory that already existed before this call. Removing it silently destroys a sysfs group that the caller did not create. Only remove the directory if we created it ourselves. On update failure the directory remains as it is left empty by remove_files() inside create_files(), but can be repopulated by a retry. Cc: Rajat Jain <rajatja@google.com> Fixes: c855cf2759d2 ("sysfs: Fix internal_create_group() for named group updates") Cc: stable <stable@kernel.org> Assisted-by: gkh_clanker_t1000 Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Link: https://patch.msgid.link/2026052003-uniquely-hastily-c093@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-11sysfs: remove trivial sysfs_get_tree() wrapperChristian Brauner
Now that FS_USERNS_MOUNT_RESTRICTED is a file_system_type flag, sysfs_get_tree() is a trivial wrapper around kernfs_get_tree() with no additional logic. Point sysfs_fs_context_ops.get_tree directly at kernfs_get_tree() and remove the wrapper. Link: https://patch.msgid.link/e8ac71fc96ad864c8b58fc0a8e5305550c01db25.1777278334.git.legion@kernel.org Reviewed-by: Aleksa Sarai <aleksa@amutable.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-05-11fs: move SB_I_USERNS_VISIBLE to FS_USERNS_MOUNT_RESTRICTEDChristian Brauner
Whether a filesystem's mounts need to undergo a visibility check in user namespaces is a static property of the filesystem type, not a runtime property of each superblock instance. Both proc and sysfs always set SB_I_USERNS_VISIBLE on their superblocks unconditionally (sysfs does so on first creation, and subsequent mounts reuse the same superblock). Move this flag from sb->s_iflags (SB_I_USERNS_VISIBLE) to file_system_type->fs_flags (FS_USERNS_MOUNT_RESTRICTED) so the intent is expressed at the filesystem type level where it belongs. All check sites are updated to test sb->s_type->fs_flags instead of sb->s_iflags. The SB_I_NOEXEC and SB_I_NODEV flags remain on the superblock as they are runtime properties set during fill_super. Link: https://patch.msgid.link/72887c5b6204dc3adf5a53104f0be6bd8bc4f6cd.1777278334.git.legion@kernel.org Reviewed-by: Aleksa Sarai <aleksa@amutable.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-05-07sysfs: upgrade OOB write by buggy .show hook into WARNingAlexey Dobriyan
Buggy .show hook will get just 1 line of dmesg: fill_read_buffer: ext4_attr_show+0x0/0x600 returned bad count It may or may not oops later in some unrelated process. But buggy .show hook most likely is corrupting random memory past sysfs buffer therefore deserving more. WARN, make it more visible and let QA machines panic earlier. Also, delete useless cast -- "count" is >=0 at this point. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Link: https://patch.msgid.link/3cc3e8c6-c6e8-4625-a88f-f5708b935dab@p183 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-19Merge tag 'driver-core-7.1-rc1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core fixes from Danilo Krummrich: - Prevent a device from being probed before device_add() has finished initializing it; gate probe with a "ready_to_probe" device flag to avoid races with concurrent driver_register() calls - Fix a kernel-doc warning for DEV_FLAG_COUNT introduced by the above - Return -ENOTCONN from software_node_get_reference_args() when a referenced software node is known but not yet registered, allowing callers to defer probe - In sysfs_group_attrs_change_owner(), also check is_visible_const(); missed when the const variant was introduced * tag 'driver-core-7.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: driver core: Add kernel-doc for DEV_FLAG_COUNT enum value sysfs: attribute_group: Respect is_visible_const() when changing owner software node: return -ENOTCONN when referenced swnode is not registered yet driver core: Don't let a device probe until it's ready
2026-04-13Merge tag 'driver-core-7.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "debugfs: - Fix NULL pointer dereference in debugfs_create_str() - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str() - Fix soundwire debugfs NULL pointer dereference from uninitialized firmware_file device property: - Make fwnode flags modifications thread safe; widen the field to unsigned long and use set_bit() / clear_bit() based accessors - Document how to check for the property presence devres: - Separate struct devres_node from its "subclasses" (struct devres, struct devres_group); give struct devres_node its own release and free callbacks for per-type dispatch - Introduce struct devres_action for devres actions, avoiding the ARCH_DMA_MINALIGN alignment overhead of struct devres - Export struct devres_node and its init/add/remove/dbginfo primitives for use by Rust Devres<T> - Fix missing node debug info in devm_krealloc() - Use guard(spinlock_irqsave) where applicable; consolidate unlock paths in devres_release_group() driver_override: - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the generic driver_override infrastructure, replacing per-bus driver_override strings, sysfs attributes, and match logic; fixes a potential UAF from unsynchronized access to driver_override in bus match() callbacks - Simplify __device_set_driver_override() logic kernfs: - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs file and directory removal - Add corresponding selftests for memcg platform: - Allow attaching software nodes when creating platform devices via a new 'swnode' field in struct platform_device_info - Add kerneldoc for struct platform_device_info software node: - Move software node initialization from postcore_initcall() to driver_init(), making it available early in the boot process - Move kernel_kobj initialization (ksysfs_init) earlier to support the above - Remove software_node_exit(); dead code in a built-in unit SoC: - Introduce of_machine_read_compatible() and of_machine_read_model() OF helpers and export soc_attr_read_machine() to replace direct accesses to of_root from SoC drivers; also enables CONFIG_COMPILE_TEST coverage for these drivers sysfs: - Constify attribute group array pointers to 'const struct attribute_group *const *' in sysfs functions, device_add_groups() / device_remove_groups(), and struct class Rust: - Devres: - Embed struct devres_node directly in Devres<T> instead of going through devm_add_action(), avoiding the extra allocation and the unnecessary ARCH_DMA_MINALIGN alignment - I/O: - Turn IoCapable from a marker trait into a functional trait carrying the raw I/O accessor implementation (io_read / io_write), providing working defaults for the per-type Io methods - Add RelaxedMmio wrapper type, making relaxed accessors usable in code generic over the Io trait - Remove overloaded per-type Io methods and per-backend macros from Mmio and PCI ConfigSpace - I/O (Register): - Add IoLoc trait and generic read/write/update methods to the Io trait, making I/O operations parameterizable by typed locations - Add register! macro for defining hardware register types with typed bitfield accessors backed by Bounded values; supports direct, relative, and array register addressing - Add write_reg() / try_write_reg() and LocatedRegister trait - Update PCI sample driver to demonstrate the register! macro Example: ``` register! { /// UART control register. CTRL(u32) @ 0x18 { /// Receiver enable. 19:19 rx_enable => bool; /// Parity configuration. 14:13 parity ?=> Parity; } /// FIFO watermark and counter register. WATER(u32) @ 0x2c { /// Number of datawords in the receive FIFO. 26:24 rx_count; /// RX interrupt threshold. 17:16 rx_water; } } impl WATER { fn rx_above_watermark(&self) -> bool { self.rx_count() > self.rx_water() } } fn init(bar: &pci::Bar<BAR0_SIZE>) { let water = WATER::zeroed() .with_const_rx_water::<1>(); // > 3 would not compile bar.write_reg(water); let ctrl = CTRL::zeroed() .with_parity(Parity::Even) .with_rx_enable(true); bar.write_reg(ctrl); } fn handle_rx(bar: &pci::Bar<BAR0_SIZE>) { if bar.read(WATER).rx_above_watermark() { // drain the FIFO } } fn set_parity(bar: &pci::Bar<BAR0_SIZE>, parity: Parity) { bar.update(CTRL, |r| r.with_parity(parity)); } ``` - IRQ: - Move 'static bounds from where clauses to trait declarations for IRQ handler traits - Misc: - Enable the generic_arg_infer Rust feature - Extend Bounded with shift operations, single-bit bool conversion, and const get() Misc: - Make deferred_probe_timeout default a Kconfig option - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM callbacks when no bus type PM ops are set - Add conditional guard support for device_lock() - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry - Fix kernel-doc warnings in base.h - Fix stale reference to memory_block_add_nid() in documentation" * tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (67 commits) bus: fsl-mc: use generic driver_override infrastructure s390/ap: use generic driver_override infrastructure s390/cio: use generic driver_override infrastructure vdpa: use generic driver_override infrastructure platform/wmi: use generic driver_override infrastructure PCI: use generic driver_override infrastructure driver core: make software nodes available earlier software node: remove software_node_exit() kernel: ksysfs: initialize kernel_kobj earlier MAINTAINERS: add ksysfs.c to the DRIVER CORE entry drivers/base/memory: fix stale reference to memory_block_add_nid() device property: Document how to check for the property presence soundwire: debugfs: initialize firmware_file to empty string debugfs: fix placement of EXPORT_SYMBOL_GPL for debugfs_create_str() debugfs: check for NULL pointer in debugfs_create_str() driver core: Make deferred_probe_timeout default a Kconfig option driver core: simplify __device_set_driver_override() clearing logic driver core: auxiliary bus: Drop auxiliary_dev_pm_ops device property: Make modifications of fwnode "flags" thread safe rust: devres: embed struct devres_node directly ...
2026-04-11sysfs: attribute_group: Respect is_visible_const() when changing ownerThomas Weißschuh
The call to grp->is_visible in sysfs_group_attrs_change_owner() was missed when support for is_visible_const() was added. Check for both is_visible variants there too. Fixes: 7dd9fdb4939b ("sysfs: attribute_group: enable const variants of is_visible()") Cc: stable@vger.kernel.org Reported-by: Michael Kelley <mhklinux@outlook.com> Closes: https://lore.kernel.org/lkml/SN6PR02MB4157D5F04608E4E3C21AB56ED45EA@SN6PR02MB4157.namprd02.prod.outlook.com/ Link: https://sashiko.dev/#/patchset/20260403-sysfs-const-hv-v2-0-8932ab8d41db%40weissschuh.net Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Link: https://patch.msgid.link/20260403-sysfs-is_visible_const-fix-v1-1-f87f26071d2c@weissschuh.net Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-04-09kernfs: pass struct ns_common instead of const void * for namespace tagsChristian Brauner
kernfs has historically used const void * to pass around namespace tags used for directory-level namespace filtering. The only current user of this is sysfs network namespace tagging where struct net pointers are cast to void *. Replace all const void * namespace parameters with const struct ns_common * throughout the kernfs, sysfs, and kobject namespace layers. This includes the kobj_ns_type_operations callbacks, kobject_namespace(), and all sysfs/kernfs APIs that accept or return namespace tags. Passing struct ns_common is needed because various codepaths require access to the underlying namespace. A struct ns_common can always be converted back to the concrete namespace type (e.g., struct net) via container_of() or to_ns_common() in the reverse direction. This is a preparatory change for switching to ns_id-based directory iteration to prevent a KASLR pointer leak through the current use of raw namespace pointers as hash seeds and comparison keys. Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-13sysfs: constify group arrays in function argumentsHeiner Kallweit
Constify the groups array argument where applicable. This allows to pass constant arrays as arguments. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Link: https://patch.msgid.link/17035265-8882-4101-b7a7-16b3eb94f8b5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-05sysfs: remove exports of sysfs_*change_owner()Greg Kroah-Hartman
Both sysfs_change_owner() and sysfs_file_change_owner() are exported to modules, but there are no in-kernel module users, so remove the exports so that crazy out-of-tree drivers don't get the impression that it is safe to call these functions at all. Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Reported-by: Lee Jones <lee@kernel.org> Reviewed-by: Lee Jones <lee@kernel.org> Link: https://patch.msgid.link/2026020541-energize-graduate-981a@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-26sysfs: attribute_group: enable const variants of is_visible()Thomas Weißschuh
When constifying instances of struct attribute, for consistency the corresponding .is_visible() callback should be adapted, too. Introduce a temporary transition mechanism until all callbacks are converted. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://patch.msgid.link/20251029-sysfs-const-attr-prep-v5-4-ea7d745acff4@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-17sysfs: check visibility before changing group attribute ownershipFernando Fernandez Mancera
Since commit 0c17270f9b92 ("net: sysfs: Implement is_visible for phys_(port_id, port_name, switch_id)"), __dev_change_net_namespace() can hit WARN_ON() when trying to change owner of a file that isn't visible. See the trace below: WARNING: CPU: 6 PID: 2938 at net/core/dev.c:12410 __dev_change_net_namespace+0xb89/0xc30 CPU: 6 UID: 0 PID: 2938 Comm: incusd Not tainted 6.17.1-1-mainline #1 PREEMPT(full) 4b783b4a638669fb644857f484487d17cb45ed1f Hardware name: Framework Laptop 13 (AMD Ryzen 7040Series)/FRANMDCP07, BIOS 03.07 02/19/2025 RIP: 0010:__dev_change_net_namespace+0xb89/0xc30 [...] Call Trace: <TASK> ? if6_seq_show+0x30/0x50 do_setlink.isra.0+0xc7/0x1270 ? __nla_validate_parse+0x5c/0xcc0 ? security_capable+0x94/0x1a0 rtnl_newlink+0x858/0xc20 ? update_curr+0x8e/0x1c0 ? update_entity_lag+0x71/0x80 ? sched_balance_newidle+0x358/0x450 ? psi_task_switch+0x113/0x2a0 ? __pfx_rtnl_newlink+0x10/0x10 rtnetlink_rcv_msg+0x346/0x3e0 ? sched_clock+0x10/0x30 ? __pfx_rtnetlink_rcv_msg+0x10/0x10 netlink_rcv_skb+0x59/0x110 netlink_unicast+0x285/0x3c0 ? __alloc_skb+0xdb/0x1a0 netlink_sendmsg+0x20d/0x430 ____sys_sendmsg+0x39f/0x3d0 ? import_iovec+0x2f/0x40 ___sys_sendmsg+0x99/0xe0 __sys_sendmsg+0x8a/0xf0 do_syscall_64+0x81/0x970 ? __sys_bind+0xe3/0x110 ? syscall_exit_work+0x143/0x1b0 ? do_syscall_64+0x244/0x970 ? sock_alloc_file+0x63/0xc0 ? syscall_exit_work+0x143/0x1b0 ? do_syscall_64+0x244/0x970 ? alloc_fd+0x12e/0x190 ? put_unused_fd+0x2a/0x70 ? do_sys_openat2+0xa2/0xe0 ? syscall_exit_work+0x143/0x1b0 ? do_syscall_64+0x244/0x970 ? exc_page_fault+0x7e/0x1a0 entry_SYSCALL_64_after_hwframe+0x76/0x7e [...] </TASK> Fix this by checking is_visible() before trying to touch the attribute. Fixes: 303a42769c4c ("sysfs: add sysfs_group{s}_change_owner()") Fixes: 0c17270f9b92 ("net: sysfs: Implement is_visible for phys_(port_id, port_name, switch_id)") Reported-by: Cynthia <cynthia@kosmx.dev> Closes: https://lore.kernel.org/netdev/01070199e22de7f8-28f711ab-d3f1-46d9-b9a0-048ab05eb09b-000000@eu-central-1.amazonses.com/ Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20251016101456.4087-1-fmancera@suse.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-19sysfs: remove bin_attribute::read_new/write_new()Thomas Weißschuh
These transitional fields are now unused and unnecessary. Remove them and their logic in the sysfs core. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://lore.kernel.org/r/20250811-sysfs-const-bin_attr-final-v4-1-7b6053fd58bb@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-17sysfs: constify internal references to 'struct bin_attribute'Thomas Weißschuh
The sysfs core handles 'const struct bin_attribute *'. Adapt the internal references. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://lore.kernel.org/r/20250530-sysfs-const-bin_attr-final-v3-2-724bfcf05b99@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-15sysfs: constify attribute_group::bin_attrsThomas Weißschuh
All users of this field have been migrated to bin_attrs_new. It can now be constified. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://lore.kernel.org/r/20250313-sysfs-const-bin_attr-final-v2-2-96284e1e88ce@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-15kernfs: Use RCU to access kernfs_node::name.Sebastian Andrzej Siewior
Using RCU lifetime rules to access kernfs_node::name can avoid the trouble with kernfs_rename_lock in kernfs_name() and kernfs_path_from_node() if the fs was created with KERNFS_ROOT_INVARIANT_PARENT. This is usefull as it allows to implement kernfs_path_from_node() only with RCU protection and avoiding kernfs_rename_lock. The lock is only required if the __parent node can be changed and the function requires an unchanged hierarchy while it iterates from the node to its parent. The change is needed to allow the lookup of the node's path (kernfs_path_from_node()) from context which runs always with disabled preemption and or interrutps even on PREEMPT_RT. The problem is that kernfs_rename_lock becomes a sleeping lock on PREEMPT_RT. I went through all ::name users and added the required access for the lookup with a few extensions: - rdtgroup_pseudo_lock_create() drops all locks and then uses the name later on. resctrl supports rename with different parents. Here I made a temporal copy of the name while it is used outside of the lock. - kernfs_rename_ns() accepts NULL as new_parent. This simplifies sysfs_move_dir_ns() where it can set NULL in order to reuse the current name. - kernfs_rename_ns() is only using kernfs_rename_lock if the parents are different. All users use either kernfs_rwsem (for stable path view) or just RCU for the lookup. The ::name uses always RCU free. Use RCU lifetime guarantees to access kernfs_node::name. Suggested-by: Tejun Heo <tj@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Reported-by: syzbot+6ea37e2e6ffccf41a7e6@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/67251dc6.050a0220.529b6.015e.GAE@google.com/ Reported-by: Hillf Danton <hdanton@sina.com> Closes: https://lore.kernel.org/20241102001224.2789-1-hdanton@sina.com Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20250213145023.2820193-7-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-15kernfs: Use RCU to access kernfs_node::parent.Sebastian Andrzej Siewior
kernfs_rename_lock is used to obtain stable kernfs_node::{name|parent} pointer. This is a preparation to access kernfs_node::parent under RCU and ensure that the pointer remains stable under the RCU lifetime guarantees. For a complete path, as it is done in kernfs_path_from_node(), the kernfs_rename_lock is still required in order to obtain a stable parent relationship while computing the relevant node depth. This must not change while the nodes are inspected in order to build the path. If the kernfs user never moves the nodes (changes the parent) then the kernfs_rename_lock is not required and the RCU guarantees are sufficient. This "restriction" can be set with KERNFS_ROOT_INVARIANT_PARENT. Otherwise the lock is required. Rename kernfs_node::parent to kernfs_node::__parent to denote the RCU access and use RCU accessor while accessing the node. Make cgroup use KERNFS_ROOT_INVARIANT_PARENT since the parent here can not change. Acked-by: Tejun Heo <tj@kernel.org> Cc: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20250213145023.2820193-6-bigeasy@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-09sysfs: constify bin_attribute argument of sysfs_bin_attr_simple_read()Thomas Weißschuh
Most users use this function through the BIN_ATTR_SIMPLE* macros, they can handle the switch transparently. Also adapt the two non-macro users in the same change. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Acked-by: Madhavan Srinivasan <maddy@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Tested-by: Aditya Gupta <adityag@linux.ibm.com> Link: https://lore.kernel.org/r/20241228-sysfs-const-bin_attr-simple-v2-1-7c6f3f1767a3@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05sysfs: bin_attribute: add const read/write callback variantsThomas Weißschuh
To make it possible to put struct bin_attribute into read-only memory, the sysfs core has to stop passing mutable pointers to the read() and write() callbacks. As there are numerous implementors of these callbacks throughout the tree it's not possible to change all of them at once. To enable a step-by-step transition, add new variants of the read() and write() callbacks which differ only in the constness of the struct bin_attribute argument. As most binary attributes are defined through macros, extend these macros to transparently handle both variants of callbacks to minimize the churn during the transition. As soon as all handlers are switch to the const variant, the non-const one can be removed together with the transition machinery. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Acked-by: Krzysztof Wilczyński <kw@linux.com> Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-9-71110628844c@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05sysfs: introduce callback attribute_group::bin_sizeThomas Weißschuh
Several drivers need to dynamically calculate the size of an binary attribute. Currently this is done by assigning attr->size from the is_bin_visible() callback. This has drawbacks: * It is not documented. * A single attribute can be instantiated multiple times, overwriting the shared size field. * It prevents the structure to be moved to read-only memory. Introduce a new dedicated callback to calculate the size of the attribute. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Acked-by: Krzysztof Wilczyński <kw@linux.com> Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-2-71110628844c@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05sysfs: explicitly pass size to sysfs_add_bin_file_mode_ns()Thomas Weißschuh
Upcoming changes to the sysfs core require the size of the created file to be overridable by the caller. Add a parameter to enable this. For now keep using attr->size in all cases. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Acked-by: Krzysztof Wilczyński <kw@linux.com> Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-1-71110628844c@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-23Merge 6.9-rc5 into driver-core-nextGreg Kroah-Hartman
We want the kernfs fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-11sysfs: Add sysfs_bin_attr_simple_read() helperLukas Wunner
When drivers expose a bin_attribute in sysfs which is backed by a buffer in memory, a common pattern is to set the @private and @size members in struct bin_attribute to the buffer's location and size. The ->read() callback then merely consists of a single memcpy() call. It's not even necessary to perform bounds checks as these are already handled by sysfs_kf_bin_read(). However each driver is so far providing its own ->read() implementation. The pattern is sufficiently frequent to merit a public helper, so add sysfs_bin_attr_simple_read() as well as BIN_ATTR_SIMPLE_RO() and BIN_ATTR_SIMPLE_ADMIN_RO() macros to ease declaration of such bin_attributes and reduce LoC and .text section size. Signed-off-by: Lukas Wunner <lukas@wunner.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/5ed62b197a442ec6db53d8746d9d806dd0576e2d.1712410202.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-11fs: sysfs: Fix reference leak in sysfs_break_active_protection()Alan Stern
The sysfs_break_active_protection() routine has an obvious reference leak in its error path. If the call to kernfs_find_and_get() fails then kn will be NULL, so the companion sysfs_unbreak_active_protection() routine won't get called (and would only cause an access violation by trying to dereference kn->parent if it was called). As a result, the reference to kobj acquired at the start of the function will never be released. Fix the leak by adding an explicit kobject_put() call when kn is NULL. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Fixes: 2afc9166f79b ("scsi: sysfs: Introduce sysfs_{un,}break_active_protection()") Cc: Bart Van Assche <bvanassche@acm.org> Cc: stable@vger.kernel.org Reviewed-by: Bart Van Assche <bvanassche@acm.org> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/8a4d3f0f-c5e3-4b70-a188-0ca433f9e6f9@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-07sysfs:Addresses documentation in sysfs_merge_group and sysfs_unmerge_group.Rohan Kollambalath
These functions take a struct attribute_group as an input which has an optional .name field. These functions rely on the .name field being populated and do not check if its null. They pass this name into other functions, eventually leading to a null pointer dereference. This change simply updates the documentation of the function to make this requirement clear. Signed-off-by: Rohan Kollambalath <rkollamb@digi.com> Link: https://lore.kernel.org/r/20240211223634.2103665-1-rohankollambalath@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23sysfs: Fix crash on empty group attributes arrayDan Williams
It turns out that arch/x86/events/intel/core.c makes use of "empty" attributes. static struct attribute *empty_attrs; __init int intel_pmu_init(void) { struct attribute **extra_skl_attr = &empty_attrs; struct attribute **extra_attr = &empty_attrs; struct attribute **td_attr = &empty_attrs; struct attribute **mem_attr = &empty_attrs; struct attribute **tsx_attr = &empty_attrs; ... That breaks the assumption __first_visible() that expects that if grp->attrs is set then grp->attrs[0] must also be set and results in backtraces like: BUG: kernel NULL pointer dereference, address: 00rnel mode #PF: error_code(0x0000) - not-present ] PREEMPT SMP NOPTI CPU: 1 PID: 1 Comm: swapper/IP: 0010:exra_is_visible+0x14/0x20 ? exc_page_fault+0x68/0x190 internal_create_groups+0x42/0xa0 pmu_dev_alloc+0xc0/0xe0 perf_event_sysfs_init+0x580000000000 ]--- RIP: 0010:exra_is_visible+0x14/0 Check for non-empty attributes array before calling is_visible(). Reported-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Closes: https://github.com/thesofproject/linux/pull/4799#issuecomment-1958537212 Fixes: 70317fd24b41 ("sysfs: Introduce a mechanism to hide static attribute_groups") Cc: Marc Herbert <marc.herbert@intel.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Marc Herbert <marc.herbert@intel.com> Link: https://lore.kernel.org/r/170863445442.1479840.1818801787239831650.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-19sysfs: Introduce a mechanism to hide static attribute_groupsDan Williams
Add a mechanism for named attribute_groups to hide their directory at sysfs_update_group() time, or otherwise skip emitting the group directory when the group is first registered. It piggybacks on is_visible() in a similar manner as SYSFS_PREALLOC, i.e. special flags in the upper bits of the returned mode. To use it, specify a symbol prefix to DEFINE_SYSFS_GROUP_VISIBLE(), and then pass that same prefix to SYSFS_GROUP_VISIBLE() when assigning the @is_visible() callback: DEFINE_SYSFS_GROUP_VISIBLE($prefix) struct attribute_group $prefix_group = { .name = $name, .is_visible = SYSFS_GROUP_VISIBLE($prefix), }; SYSFS_GROUP_VISIBLE() expects a definition of $prefix_group_visible() and $prefix_attr_visible(), where $prefix_group_visible() just returns true / false and $prefix_attr_visible() behaves as normal. The motivation for this capability is to centralize PCI device authentication in the PCI core with a named sysfs group while keeping that group hidden for devices and platforms that do not meet the requirements. In a PCI topology, most devices will not support authentication, a small subset will support just PCI CMA (Component Measurement and Authentication), a smaller subset will support PCI CMA + PCIe IDE (Link Integrity and Encryption), and only next generation server hosts will start to include a platform TSM (TEE Security Manager). Without this capability the alternatives are: * Check if all attributes are invisible and if so, hide the directory. Beyond trouble getting this to work [1], this is an ABI change for scenarios if userspace happens to depend on group visibility absent any attributes. I.e. this new capability avoids regression since it does not retroactively apply to existing cases. * Publish an empty /sys/bus/pci/devices/$pdev/tsm/ directory for all PCI devices (i.e. for the case when TSM platform support is present, but device support is absent). Unfortunate that this will be a vestigial empty directory in the vast majority of cases. * Reintroduce usage of runtime calls to sysfs_{create,remove}_group() in the PCI core. Bjorn has already indicated that he does not want to see any growth of pci_sysfs_init() [2]. * Drop the named group and simulate a directory by prefixing all TSM-related attributes with "tsm_". Unfortunate to not use the naming capability of a sysfs group as intended. In comparison, there is a small potential for regression if for some reason an @is_visible() callback had dependencies on how many times it was called. Additionally, it is no longer an error to update a group that does not have its directory already present, and it is no longer a WARN() to remove a group that was never visible. Link: https://lore.kernel.org/all/2024012321-envious-procedure-4a58@gregkh/ [1] Link: https://lore.kernel.org/linux-pci/20231019200110.GA1410324@bhelgaas/ [2] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/2024013028-deflator-flaring-ec62@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-07fs/sysfs/dir.c : Fix typo in commentMukesh Ojha
Typo correction kboject => kobject Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com> Link: https://lore.kernel.org/r/1698661274-32540-1-git-send-email-quic_mojha@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-05kernfs: sysfs: support custom llseek method for sysfs entriesValentine Sinitsyn
As of now, seeking in sysfs files is handled by generic_file_llseek(). There are situations where one may want to customize seeking logic: - Many sysfs entries are fixed files while generic_file_llseek() accepts past-the-end positions. Not only being useless by itself, this also means a bug in userspace code will trigger not at lseek(), but at some later point making debugging harder. - generic_file_llseek() relies on f_mapping->host to get the file size which might not be correct for all sysfs entries. See commit 636b21b50152 ("PCI: Revoke mappings like devmem") as an example. Implement llseek method to override this behavior at sysfs attribute level. The method is optional, and if it is absent, generic_file_llseek() is called to preserve backwards compatibility. Signed-off-by: Valentine Sinitsyn <valesini@yandex-team.ru> Link: https://lore.kernel.org/r/20230925084013.309399-1-valesini@yandex-team.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15sysfs: Skip empty folders creationMiquel Raynal
Most sysfs attributes are statically defined, the goal with this design being to be able to move all the filesystem description into read-only memory. Anyway, it may be relevant in some cases to populate attributes at run time. This leads to situation where an attribute may or may not be present depending on conditions which are not known at compile time, up to the point where no attribute at all gets added in a folder which then becomes "sometimes" empty. Problem is, providing an attribute group with a name and without .[bin_]attrs members will be loudly refused by the core, leading in most cases to a device registration failure. The simple way to support such situation right now is to dynamically allocate an empty attribute array, which is: * a (small) waste of space * a waste of time * disturbing, to say the least, as an empty sysfs folder will be created anyway. Another (even worse) possibility would be to dynamically overwrite a member of the attribute_group list, hopefully the last, which is also supposed to remain in the read-only section. In order to avoid these hackish situations, while still giving a little bit of flexibility, we might just check the validity of the .[bin_]attrs list and, if empty, just skip the attribute group creation instead of failing. This way, developers will not be tempted to workaround the core with useless allocations or strange writes on supposedly read-only structures. The content of the WARN() message is kept but turned into a debug message in order to help developers understanding why their sysfs folders might now silently fail to be created. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Message-ID: <20230614063018.2419043-3-miquel.raynal@bootlin.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15sysfs: Improve readability by following the kernel coding styleMiquel Raynal
The purpose of the if/else block is to select the right sysfs directory entry to be used for the files creation. At a first look when you have the file in front of you, it really seems like the "create_files()" lines right after the block are badly indented and the "else" does not guard. In practice the code is correct but lacks curly brackets to show where the big if/else block actually ends. Add these brackets to comply with the current kernel coding style and to ease the understanding of the whole logic. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Message-ID: <20230614063018.2419043-2-miquel.raynal@bootlin.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-05kobject: kobj_type: remove default_attrsGreg Kroah-Hartman
Now that all in-kernel users of default_attrs for the kobj_type are gone and converted to properly use the default_groups pointer instead, it can be safely removed. There is one standard way to create sysfs files in a kobj_type, and not two like before, causing confusion as to which should be used. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Link: https://lore.kernel.org/r/20220106133151.607703-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-23kernfs: move struct kernfs_root out of the public view.Greg Kroah-Hartman
There is no need to have struct kernfs_root be part of kernfs.h for the whole kernel to see and poke around it. Move it internal to kernfs code and provide a helper function, kernfs_root_to_node(), to handle the one field that kernfs users were directly accessing from the structure. Cc: Imran Khan <imran.f.khan@oracle.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220222070713.3517679-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-05fs/sysfs/dir.c: replace S_IRWXU|S_IRUGO|S_IXUGO with 0755 sysfs_create_dir_ns()Luis Chamberlain
If one ends up expanding on this line checkpatch will complain that the combination S_IRWXU|S_IRUGO|S_IXUGO should just be replaced with the octal 0755. Do that. This makes no functional changes. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20210927163805.808907-9-mcgrof@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-14sysfs: simplify sysfs_kf_seq_showChristoph Hellwig
Contrary to the comment ->show is never called from lseek for sysfs, given that sysfs does not use seq_lseek. So remove the NULL ->show case and just WARN and return an error if some future code path ends up here. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210913054121.616001-7-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-14sysfs: refactor sysfs_add_file_mode_nsChristoph Hellwig
Regroup the code so that preallocated attributes and normal attributes are handled in clearly separate blocks. Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210913054121.616001-6-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-14sysfs: split out binary attribute handling from sysfs_add_file_mode_nsChristoph Hellwig
Split adding binary attributes into a separate handler instead of overloading sysfs_add_file_mode_ns. Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210913054121.616001-5-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-06Merge tag 'sysfs_defferred_iomem_get_mapping-5.15' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core driver-core-next sysfs: Allow deferred execution of iomem_get_mapping() Tag for toerh trees/branches to pull from in order to have a stable base to build off of for the "Allow deferred execution of iomem_get_mapping()" set of sysfs changes Link: https://lore.kernel.org/r/20210729233235.1508920-1-kw@linux.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> * tag 'sysfs_defferred_iomem_get_mapping-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: sysfs: Rename struct bin_attribute member to f_mapping sysfs: Invoke iomem_get_mapping() from the sysfs open callback
2021-08-05sysfs: Rename struct bin_attribute member to f_mappingKrzysztof Wilczyński
There are two users of iomem_get_mapping(), the struct file and struct bin_attribute. The former has a member called "f_mapping" and the latter has a member called "mapping", and both are poniters to struct address_space. Rename struct bin_attribute member to "f_mapping" to keep both meaning and the usage consistent with other users of iomem_get_mapping(). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Krzysztof Wilczyński <kw@linux.com> Link: https://lore.kernel.org/r/20210729233235.1508920-3-kw@linux.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-05sysfs: Invoke iomem_get_mapping() from the sysfs open callbackKrzysztof Wilczyński
Defer invocation of the iomem_get_mapping() to the sysfs open callback so that it can be executed as needed when the binary sysfs object has been accessed. To do that, convert the "mapping" member of the struct bin_attribute from a pointer to the struct address_space into a function pointer with a signature that requires the same return type, and then updates the sysfs_kf_bin_open() to invoke provided function should the function pointer be valid. Also, convert every invocation of iomem_get_mapping() into a function pointer assignment, therefore allowing for the iomem_get_mapping() invocation to be deferred to when the sysfs open callback runs. Thus, this change removes the need for the fs_initcalls to complete before any other sub-system that uses the iomem_get_mapping() would be able to invoke it safely without leading to a failure and an Oops related to an invalid iomem_get_mapping() access. Suggested-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Krzysztof Wilczyński <kw@linux.com> Link: https://lore.kernel.org/r/20210729233235.1508920-2-kw@linux.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-21sysfs: Use local reference in compat_only_sysfs_link_entry_to_kobj()Geert Uytterhoeven
As we have just obtained target_kobj->sd into a local variable, and incremented the object's reference count, it is better to use the local variable instead of the original reference. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20210714151559.2532572-1-geert@linux-m68k.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-12sysfs: Support zapping of binary attr mmapsDaniel Vetter
We want to be able to revoke pci mmaps so that the same access rules applies as for /dev/kmem. Revoke support for devmem was added in 3234ac664a87 ("/dev/mem: Revoke mappings when a driver claims the region"). The simplest way to achieve this is by having the same filp->f_mapping for all mappings, so that unmap_mapping_range can find them all, no matter through which file they've been created. Since this must be set at open time we need sysfs support for this. Add an optional mapping parameter bin_attr, which is only consulted when there's also an mmap callback, since without mmap support allowing to adjust the ->f_mapping makes no sense. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-pci@vger.kernel.org Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Sourabh Jain <sourabhjain@linux.ibm.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Cc: Nayna Jain <nayna@linux.ibm.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-12-daniel.vetter@ffwll.ch
2020-10-02sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs outputJoe Perches
Output defects can exist in sysfs content using sprintf and snprintf. sprintf does not know the PAGE_SIZE maximum of the temporary buffer used for outputting sysfs content and it's possible to overrun the PAGE_SIZE buffer length. Add a generic sysfs_emit function that knows that the size of the temporary buffer and ensures that no overrun is done. Add a generic sysfs_emit_at function that can be used in multiple call situations that also ensures that no overrun is done. Validate the output buffer argument to be page aligned. Validate the offset len argument to be within the PAGE_SIZE buf. Signed-off-by: Joe Perches <joe@perches.com> Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull rdma updates from Jason Gunthorpe: "A more active cycle than most of the recent past, with a few large, long discussed works this time. The RNBD block driver has been posted for nearly two years now, and flowing through RDMA due to it also introducing a new ULP. The removal of FMR has been a recurring discussion theme for a long time. And the usual smattering of features and bug fixes. Summary: - Various small driver bugs fixes in rxe, mlx5, hfi1, and efa - Continuing driver cleanups in bnxt_re, hns - Big cleanup of mlx5 QP creation flows - More consistent use of src port and flow label when LAG is used and a mlx5 implementation - Additional set of cleanups for IB CM - 'RNBD' network block driver and target. This is a network block RDMA device specific to ionos's cloud environment. It brings strong multipath and resiliency capabilities. - Accelerated IPoIB for HFI1 - QP/WQ/SRQ ioctl migration for uverbs, and support for multiple async fds - Support for exchanging the new IBTA defiend ECE data during RDMA CM exchanges - Removal of the very old and insecure FMR interface from all ULPs and drivers. FRWR should be preferred for at least a decade now" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (247 commits) RDMA/cm: Spurious WARNING triggered in cm_destroy_id() RDMA/mlx5: Return ECE DC support RDMA/mlx5: Don't rely on FW to set zeros in ECE response RDMA/mlx5: Return an error if copy_to_user fails IB/hfi1: Use free_netdev() in hfi1_netdev_free() RDMA/hns: Uninitialized variable in modify_qp_init_to_rtr() RDMA/core: Move and rename trace_cm_id_create() IB/hfi1: Fix hfi1_netdev_rx_init() error handling RDMA: Remove 'max_map_per_fmr' RDMA: Remove 'max_fmr' RDMA/core: Remove FMR device ops RDMA/rdmavt: Remove FMR memory registration RDMA/mthca: Remove FMR support for memory registration RDMA/mlx4: Remove FMR support for memory registration RDMA/i40iw: Remove FMR leftovers RDMA/bnxt_re: Remove FMR leftovers RDMA/mlx5: Remove FMR leftovers RDMA/core: Remove FMR pool API RDMA/rds: Remove FMR support for memory registration RDMA/srp: Remove support for FMR memory registration ...