Merge tag 'driver-core-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2cd5769f · Linus Torvalds <[email protected]> · 2025-04-01 11:02:03 -07:00

Pull driver core updatesk from Greg KH:
 "Here is the big set of driver core updates for 6.15-rc1. Lots of stuff
  happened this development cycle, including:

   - kernfs scaling changes to make it even faster thanks to rcu

   - bin_attribute constify work in many subsystems

   - faux bus minor tweaks for the rust bindings

   - rust binding updates for driver core, pci, and platform busses,
     making more functionaliy available to rust drivers. These are all
     due to people actually trying to use the bindings that were in
     6.14.

   - make Rafael and Danilo full co-maintainers of the driver core
     codebase

   - other minor fixes and updates"

* tag 'driver-core-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (52 commits)
  rust: platform: require Send for Driver trait implementers
  rust: pci: require Send for Driver trait implementers
  rust: platform: impl Send + Sync for platform::Device
  rust: pci: impl Send + Sync for pci::Device
  rust: platform: fix unrestricted &mut platform::Device
  rust: pci: fix unrestricted &mut pci::Device
  rust: device: implement device context marker
  rust: pci: use to_result() in enable_device_mem()
  MAINTAINERS: driver core: mark Rafael and Danilo as co-maintainers
  rust/kernel/faux: mark Registration methods inline
  driver core: faux: only create the device if probe() succeeds
  rust/faux: Add missing parent argument to Registration::new()
  rust/faux: Drop #[repr(transparent)] from faux::Registration
  rust: io: fix devres test with new io accessor functions
  rust: io: rename `io::Io` accessors
  kernfs: Move dput() outside of the RCU section.
  efi: rci2: mark bin_attribute as __ro_after_init
  rapidio: constify 'struct bin_attribute'
  firmware: qemu_fw_cfg: constify 'struct bin_attribute'
  powerpc/perf/hv-24x7: Constify 'struct bin_attribute'
  ...

Commit: 2cd5769fb0b78b8ef583ab4c0015c2c48d525dac
Parents: d6b02199 · 51d0de75

Merge commit. Changes below are compared with the first parent: d6b02199.

Changes

62 files changed · +742 −453

File	Status	Add	Del	Content
MAINTAINERS	modified	+4	−2	View file
arch/powerpc/kernel/secvar-sysfs.c	modified	+12	−12	View file
arch/powerpc/perf/hv-24x7.c	modified	+4	−4	View file
arch/powerpc/platforms/powernv/opal-core.c	modified	+5	−5	View file
arch/powerpc/platforms/powernv/opal-dump.c	modified	+2	−2	View file
arch/powerpc/platforms/powernv/opal-elog.c	modified	+2	−2	View file
arch/powerpc/platforms/powernv/opal-flash.c	modified	+2	−2	View file
arch/powerpc/platforms/powernv/opal-msglog.c	modified	+3	−3	View file
arch/powerpc/platforms/powernv/ultravisor.c	modified	+3	−3	View file
arch/x86/kernel/cpu/resctrl/internal.h	modified	+5	−0	View file
arch/x86/kernel/cpu/resctrl/pseudo_lock.c	modified	+10	−4	View file
arch/x86/kernel/cpu/resctrl/rdtgroup.c	modified	+48	−25	View file
drivers/accel/habanalabs/common/sysfs.c	modified	+5	−5	View file
drivers/base/bus.c	modified	+1	−1	View file
drivers/base/component.c	modified	+6	−6	View file
drivers/base/faux.c	modified	+14	−1	View file
drivers/base/physical_location.c	modified	+3	−2	View file
drivers/cxl/port.c	modified	+5	−5	View file
drivers/firmware/dmi-sysfs.c	modified	+11	−17	View file
drivers/firmware/dmi_scan.c	modified	+2	−2	View file
drivers/firmware/efi/mokvar-table.c	modified	+2	−2	View file
drivers/firmware/efi/rci2-table.c	modified	+1	−1	View file
drivers/firmware/qemu_fw_cfg.c	modified	+3	−3	View file
drivers/fsi/fsi-core.c	modified	+4	−4	View file
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c	modified	+3	−3	View file
drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c	modified	+7	−7	View file
drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c	modified	+6	−7	View file
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_hdcp.c	modified	+4	−4	View file
drivers/gpu/drm/drm_sysfs.c	modified	+5	−5	View file
drivers/gpu/drm/i915/i915_gpu_error.c	modified	+4	−4	View file
drivers/gpu/drm/i915/i915_sysfs.c	modified	+6	−6	View file
drivers/gpu/drm/lima/lima_drv.c	modified	+4	−4	View file
drivers/gpu/nova-core/driver.rs	modified	+2	−2	View file
drivers/gpu/nova-core/regs.rs	modified	+1	−1	View file
drivers/input/touchscreen/goodix_berlin_core.c	modified	+5	−5	View file
drivers/pcmcia/cistpl.c	modified	+4	−4	View file
drivers/rapidio/rio-sysfs.c	modified	+7	−7	View file
fs/kernfs/dir.c	modified	+122	−87	View file
fs/kernfs/file.c	modified	+5	−1	View file
fs/kernfs/kernfs-internal.h	modified	+34	−3	View file
fs/kernfs/mount.c	modified	+33	−11	View file
fs/kernfs/symlink.c	modified	+16	−14	View file
fs/sysfs/dir.c	modified	+1	−1	View file
fs/sysfs/file.c	modified	+15	−9	View file
include/linux/device.h	modified	+1	−1	View file
include/linux/device/class.h	modified	+1	−1	View file
include/linux/kernfs.h	modified	+11	−3	View file
kernel/Kconfig.hz	modified	+1	−1	View file
kernel/cgroup/cgroup-v1.c	modified	+1	−1	View file
kernel/cgroup/cgroup.c	modified	+19	−5	View file
rust/kernel/device.rs	modified	+26	−0	View file
rust/kernel/devres.rs	modified	+1	−1	View file
rust/kernel/faux.rs	modified	+13	−3	View file
rust/kernel/io.rs	modified	+33	−33	View file
rust/kernel/pci.rs	modified	+93	−53	View file
rust/kernel/platform.rs	modified	+73	−31	View file
samples/rust/rust_dma.rs	modified	+4	−4	View file
samples/rust/rust_driver_faux.rs	modified	+1	−1	View file
samples/rust/rust_driver_pci.rs	modified	+10	−10	View file
samples/rust/rust_driver_platform.rs	modified	+7	−4	View file
security/selinux/hooks.c	modified	+5	−2	View file
tools/testing/selftests/bpf/progs/profiler.inc.h	modified	+1	−1	View file

Only the first 600 diff lines are shown. Download the complete patch.

MAINTAINERS

View file

diff --git a/MAINTAINERS b/MAINTAINERS
index c9bb6e1..46b6869 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7193,15 +7193,17 @@ F:	include/linux/component.h
 
 DRIVER CORE, KOBJECTS, DEBUGFS AND SYSFS
 M:	Greg Kroah-Hartman <[email protected]>
-R:	"Rafael J. Wysocki" <[email protected]>
-R:	Danilo Krummrich <[email protected]>
+M:	"Rafael J. Wysocki" <[email protected]>
+M:	Danilo Krummrich <[email protected]>
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git
 F:	Documentation/core-api/kobject.rst
 F:	drivers/base/
 F:	fs/debugfs/
 F:	fs/sysfs/
+F:	include/linux/device/
 F:	include/linux/debugfs.h
+F:	include/linux/device.h
 F:	include/linux/fwnode.h
 F:	include/linux/kobj*
 F:	include/linux/property.h

arch/powerpc/kernel/secvar-sysfs.c

View file

diff --git a/arch/powerpc/kernel/secvar-sysfs.c b/arch/powerpc/kernel/secvar-sysfs.c
index fbeb1cb..afb690a 100644
--- a/arch/powerpc/kernel/secvar-sysfs.c
+++ b/arch/powerpc/kernel/secvar-sysfs.c
@@ -52,7 +52,7 @@ static ssize_t size_show(struct kobject *kobj, struct kobj_attribute *attr,
 }
 
 static ssize_t data_read(struct file *filep, struct kobject *kobj,
-			 struct bin_attribute *attr, char *buf, loff_t off,
+			 const struct bin_attribute *attr, char *buf, loff_t off,
 			 size_t count)
 {
 	char *data;
@@ -85,7 +85,7 @@ data_fail:
 }
 
 static ssize_t update_write(struct file *filep, struct kobject *kobj,
-			    struct bin_attribute *attr, char *buf, loff_t off,
+			    const struct bin_attribute *attr, char *buf, loff_t off,
 			    size_t count)
 {
 	int rc;
@@ -104,11 +104,11 @@ static struct kobj_attribute format_attr = __ATTR_RO(format);
 
 static struct kobj_attribute size_attr = __ATTR_RO(size);
 
-static struct bin_attribute data_attr = __BIN_ATTR_RO(data, 0);
+static struct bin_attribute data_attr __ro_after_init = __BIN_ATTR_RO(data, 0);
 
-static struct bin_attribute update_attr = __BIN_ATTR_WO(update, 0);
+static struct bin_attribute update_attr __ro_after_init = __BIN_ATTR_WO(update, 0);
 
-static struct bin_attribute *secvar_bin_attrs[] = {
+static const struct bin_attribute *const secvar_bin_attrs[] = {
 	&data_attr,
 	&update_attr,
 	NULL,
@@ -121,7 +121,7 @@ static struct attribute *secvar_attrs[] = {
 
 static const struct attribute_group secvar_attr_group = {
 	.attrs = secvar_attrs,
-	.bin_attrs = secvar_bin_attrs,
+	.bin_attrs_new = secvar_bin_attrs,
 };
 __ATTRIBUTE_GROUPS(secvar_attr);
 
@@ -130,7 +130,7 @@ static const struct kobj_type secvar_ktype = {
 	.default_groups = secvar_attr_groups,
 };
 
-static int update_kobj_size(void)
+static __init int update_kobj_size(void)
 {
 
 	u64 varsize;
@@ -145,7 +145,7 @@ static int update_kobj_size(void)
 	return 0;
 }
 
-static int secvar_sysfs_config(struct kobject *kobj)
+static __init int secvar_sysfs_config(struct kobject *kobj)
 {
 	struct attribute_group config_group = {
 		.name = "config",
@@ -158,7 +158,7 @@ static int secvar_sysfs_config(struct kobject *kobj)
 	return 0;
 }
 
-static int add_var(const char *name)
+static __init int add_var(const char *name)
 {
 	struct kobject *kobj;
 	int rc;
@@ -181,7 +181,7 @@ static int add_var(const char *name)
 	return 0;
 }
 
-static int secvar_sysfs_load(void)
+static __init int secvar_sysfs_load(void)
 {
 	u64 namesize = 0;
 	char *name;
@@ -209,7 +209,7 @@ static int secvar_sysfs_load(void)
 	return rc;
 }
 
-static int secvar_sysfs_load_static(void)
+static __init int secvar_sysfs_load_static(void)
 {
 	const char * const *name_ptr = secvar_ops->var_names;
 	int rc;
@@ -224,7 +224,7 @@ static int secvar_sysfs_load_static(void)
 	return 0;
 }
 
-static int secvar_sysfs_init(void)
+static __init int secvar_sysfs_init(void)
 {
 	u64 max_size;
 	int rc;

arch/powerpc/perf/hv-24x7.c

View file

diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c
index d400fa3..b0768f3 100644
--- a/arch/powerpc/perf/hv-24x7.c
+++ b/arch/powerpc/perf/hv-24x7.c
@@ -998,7 +998,7 @@ e_out:
 }
 
 static ssize_t catalog_read(struct file *filp, struct kobject *kobj,
-			    struct bin_attribute *bin_attr, char *buf,
+			    const struct bin_attribute *bin_attr, char *buf,
 			    loff_t offset, size_t count)
 {
 	long hret;
@@ -1108,14 +1108,14 @@ PAGE_0_ATTR(catalog_version, "%lld\n",
 		(unsigned long long)be64_to_cpu(page_0->version));
 PAGE_0_ATTR(catalog_len, "%lld\n",
 		(unsigned long long)be32_to_cpu(page_0->length) * 4096);
-static BIN_ATTR_RO(catalog, 0/* real length varies */);
+static const BIN_ATTR_RO(catalog, 0/* real length varies */);
 static DEVICE_ATTR_RO(domains);
 static DEVICE_ATTR_RO(sockets);
 static DEVICE_ATTR_RO(chipspersocket);
 static DEVICE_ATTR_RO(coresperchip);
 static DEVICE_ATTR_RO(cpumask);
 
-static struct bin_attribute *if_bin_attrs[] = {
+static const struct bin_attribute *const if_bin_attrs[] = {
 	&bin_attr_catalog,
 	NULL,
 };
@@ -1141,7 +1141,7 @@ static struct attribute *if_attrs[] = {
 
 static const struct attribute_group if_group = {
 	.name = "interface",
-	.bin_attrs = if_bin_attrs,
+	.bin_attrs_new = if_bin_attrs,
 	.attrs = if_attrs,
 };
 

arch/powerpc/platforms/powernv/opal-core.c

View file

diff --git a/arch/powerpc/platforms/powernv/opal-core.c b/arch/powerpc/platforms/powernv/opal-core.c
index a379ff8..e652da8 100644
--- a/arch/powerpc/platforms/powernv/opal-core.c
+++ b/arch/powerpc/platforms/powernv/opal-core.c
@@ -159,7 +159,7 @@ static Elf64_Word *__init auxv_to_elf64_notes(Elf64_Word *buf,
  * Returns number of bytes read on success, -errno on failure.
  */
 static ssize_t read_opalcore(struct file *file, struct kobject *kobj,
-			     struct bin_attribute *bin_attr, char *to,
+			     const struct bin_attribute *bin_attr, char *to,
 			     loff_t pos, size_t count)
 {
 	struct opalcore *m;
@@ -206,9 +206,9 @@ static ssize_t read_opalcore(struct file *file, struct kobject *kobj,
 	return (tpos - pos);
 }
 
-static struct bin_attribute opal_core_attr = {
+static struct bin_attribute opal_core_attr __ro_after_init = {
 	.attr = {.name = "core", .mode = 0400},
-	.read = read_opalcore
+	.read_new = read_opalcore
 };
 
 /*
@@ -599,7 +599,7 @@ static struct attribute *mpipl_attr[] = {
 	NULL,
 };
 
-static struct bin_attribute *mpipl_bin_attr[] = {
+static const struct bin_attribute *const mpipl_bin_attr[] = {
 	&opal_core_attr,
 	NULL,
 
@@ -607,7 +607,7 @@ static struct bin_attribute *mpipl_bin_attr[] = {
 
 static const struct attribute_group mpipl_group = {
 	.attrs = mpipl_attr,
-	.bin_attrs =  mpipl_bin_attr,
+	.bin_attrs_new =  mpipl_bin_attr,
 };
 
 static int __init opalcore_init(void)

arch/powerpc/platforms/powernv/opal-dump.c

View file

diff --git a/arch/powerpc/platforms/powernv/opal-dump.c b/arch/powerpc/platforms/powernv/opal-dump.c
index 608e4b6..27e2569 100644
--- a/arch/powerpc/platforms/powernv/opal-dump.c
+++ b/arch/powerpc/platforms/powernv/opal-dump.c
@@ -286,7 +286,7 @@ out:
 }
 
 static ssize_t dump_attr_read(struct file *filep, struct kobject *kobj,
-			      struct bin_attribute *bin_attr,
+			      const struct bin_attribute *bin_attr,
 			      char *buffer, loff_t pos, size_t count)
 {
 	ssize_t rc;
@@ -342,7 +342,7 @@ static void create_dump_obj(uint32_t id, size_t size, uint32_t type)
 	dump->dump_attr.attr.name = "dump";
 	dump->dump_attr.attr.mode = 0400;
 	dump->dump_attr.size = size;
-	dump->dump_attr.read = dump_attr_read;
+	dump->dump_attr.read_new = dump_attr_read;
 
 	dump->id = id;
 	dump->size = size;

arch/powerpc/platforms/powernv/opal-elog.c

View file

diff --git a/arch/powerpc/platforms/powernv/opal-elog.c b/arch/powerpc/platforms/powernv/opal-elog.c
index 5db1e73..de33f35 100644
--- a/arch/powerpc/platforms/powernv/opal-elog.c
+++ b/arch/powerpc/platforms/powernv/opal-elog.c
@@ -156,7 +156,7 @@ static const struct kobj_type elog_ktype = {
 #define OPAL_MAX_ERRLOG_SIZE	16384
 
 static ssize_t raw_attr_read(struct file *filep, struct kobject *kobj,
-			     struct bin_attribute *bin_attr,
+			     const struct bin_attribute *bin_attr,
 			     char *buffer, loff_t pos, size_t count)
 {
 	int opal_rc;
@@ -203,7 +203,7 @@ static void create_elog_obj(uint64_t id, size_t size, uint64_t type)
 	elog->raw_attr.attr.name = "raw";
 	elog->raw_attr.attr.mode = 0400;
 	elog->raw_attr.size = size;
-	elog->raw_attr.read = raw_attr_read;
+	elog->raw_attr.read_new = raw_attr_read;
 
 	elog->id = id;
 	elog->size = size;

arch/powerpc/platforms/powernv/opal-flash.c

View file

diff --git a/arch/powerpc/platforms/powernv/opal-flash.c b/arch/powerpc/platforms/powernv/opal-flash.c
index d5ea04e..fd8c862 100644
--- a/arch/powerpc/platforms/powernv/opal-flash.c
+++ b/arch/powerpc/platforms/powernv/opal-flash.c
@@ -432,7 +432,7 @@ static int alloc_image_buf(char *buffer, size_t count)
  * and pre-allocate required memory.
  */
 static ssize_t image_data_write(struct file *filp, struct kobject *kobj,
-				struct bin_attribute *bin_attr,
+				const struct bin_attribute *bin_attr,
 				char *buffer, loff_t pos, size_t count)
 {
 	int rc;
@@ -493,7 +493,7 @@ out:
 static const struct bin_attribute image_data_attr = {
 	.attr = {.name = "image", .mode = 0200},
 	.size = MAX_IMAGE_SIZE,	/* Limit image size */
-	.write = image_data_write,
+	.write_new = image_data_write,
 };
 
 static struct kobj_attribute validate_attribute =

arch/powerpc/platforms/powernv/opal-msglog.c

View file

diff --git a/arch/powerpc/platforms/powernv/opal-msglog.c b/arch/powerpc/platforms/powernv/opal-msglog.c
index 22d6efe..f1988d0 100644
--- a/arch/powerpc/platforms/powernv/opal-msglog.c
+++ b/arch/powerpc/platforms/powernv/opal-msglog.c
@@ -94,15 +94,15 @@ ssize_t opal_msglog_copy(char *to, loff_t pos, size_t count)
 }
 
 static ssize_t opal_msglog_read(struct file *file, struct kobject *kobj,
-				struct bin_attribute *bin_attr, char *to,
+				const struct bin_attribute *bin_attr, char *to,
 				loff_t pos, size_t count)
 {
 	return opal_msglog_copy(to, pos, count);
 }
 
-static struct bin_attribute opal_msglog_attr = {
+static struct bin_attribute opal_msglog_attr __ro_after_init = {
 	.attr = {.name = "msglog", .mode = 0400},
-	.read = opal_msglog_read
+	.read_new = opal_msglog_read
 };
 
 struct memcons *__init memcons_init(struct device_node *node, const char *mc_prop_name)

arch/powerpc/platforms/powernv/ultravisor.c

View file

diff --git a/arch/powerpc/platforms/powernv/ultravisor.c b/arch/powerpc/platforms/powernv/ultravisor.c
index 67c8c4b..157d9a8 100644
--- a/arch/powerpc/platforms/powernv/ultravisor.c
+++ b/arch/powerpc/platforms/powernv/ultravisor.c
@@ -32,15 +32,15 @@ int __init early_init_dt_scan_ultravisor(unsigned long node, const char *uname,
 static struct memcons *uv_memcons;
 
 static ssize_t uv_msglog_read(struct file *file, struct kobject *kobj,
-			      struct bin_attribute *bin_attr, char *to,
+			      const struct bin_attribute *bin_attr, char *to,
 			      loff_t pos, size_t count)
 {
 	return memcons_copy(uv_memcons, to, pos, count);
 }
 
-static struct bin_attribute uv_msglog_attr = {
+static struct bin_attribute uv_msglog_attr __ro_after_init = {
 	.attr = {.name = "msglog", .mode = 0400},
-	.read = uv_msglog_read
+	.read_new = uv_msglog_read
 };
 
 static int __init uv_init(void)

arch/x86/kernel/cpu/resctrl/internal.h

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diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index c44c5b4..eaae996 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -403,6 +403,11 @@ static inline struct rdt_hw_resource *resctrl_to_arch_res(struct rdt_resource *r
 
 extern struct mutex rdtgroup_mutex;
 
+static inline const char *rdt_kn_name(const struct kernfs_node *kn)
+{
+	return rcu_dereference_check(kn->name, lockdep_is_held(&rdtgroup_mutex));
+}
+
 extern struct rdt_hw_resource rdt_resources_all[];
 extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;

arch/x86/kernel/cpu/resctrl/pseudo_lock.c

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diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 01fa789..92ea147 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -52,7 +52,8 @@ static char *pseudo_lock_devnode(const struct device *dev, umode_t *mode)
 	rdtgrp = dev_get_drvdata(dev);
 	if (mode)
 		*mode = 0600;
-	return kasprintf(GFP_KERNEL, "pseudo_lock/%s", rdtgrp->kn->name);
+	guard(mutex)(&rdtgroup_mutex);
+	return kasprintf(GFP_KERNEL, "pseudo_lock/%s", rdt_kn_name(rdtgrp->kn));
 }
 
 static const struct class pseudo_lock_class = {
@@ -1298,6 +1299,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 	struct task_struct *thread;
 	unsigned int new_minor;
 	struct device *dev;
+	char *kn_name __free(kfree) = NULL;
 	int ret;
 
 	ret = pseudo_lock_region_alloc(plr);
@@ -1309,6 +1311,11 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 		ret = -EINVAL;
 		goto out_region;
 	}
+	kn_name = kstrdup(rdt_kn_name(rdtgrp->kn), GFP_KERNEL);
+	if (!kn_name) {
+		ret = -ENOMEM;
+		goto out_cstates;
+	}
 
 	plr->thread_done = 0;
 
@@ -1353,8 +1360,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 	mutex_unlock(&rdtgroup_mutex);
 
 	if (!IS_ERR_OR_NULL(debugfs_resctrl)) {
-		plr->debugfs_dir = debugfs_create_dir(rdtgrp->kn->name,
-						      debugfs_resctrl);
+		plr->debugfs_dir = debugfs_create_dir(kn_name, debugfs_resctrl);
 		if (!IS_ERR_OR_NULL(plr->debugfs_dir))
 			debugfs_create_file("pseudo_lock_measure", 0200,
 					    plr->debugfs_dir, rdtgrp,
@@ -1363,7 +1369,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	dev = device_create(&pseudo_lock_class, NULL,
 			    MKDEV(pseudo_lock_major, new_minor),
-			    rdtgrp, "%s", rdtgrp->kn->name);
+			    rdtgrp, "%s", kn_name);
 
 	mutex_lock(&rdtgroup_mutex);
 

arch/x86/kernel/cpu/resctrl/rdtgroup.c

View file

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index c6274d4..93ec829 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -944,14 +944,14 @@ int proc_resctrl_show(struct seq_file *s, struct pid_namespace *ns,
 			continue;
 
 		seq_printf(s, "res:%s%s\n", (rdtg == &rdtgroup_default) ? "/" : "",
-			   rdtg->kn->name);
+			   rdt_kn_name(rdtg->kn));
 		seq_puts(s, "mon:");
 		list_for_each_entry(crg, &rdtg->mon.crdtgrp_list,
 				    mon.crdtgrp_list) {
 			if (!resctrl_arch_match_rmid(tsk, crg->mon.parent->closid,
 						     crg->mon.rmid))
 				continue;
-			seq_printf(s, "%s", crg->kn->name);
+			seq_printf(s, "%s", rdt_kn_name(crg->kn));
 			break;
 		}
 		seq_putc(s, '\n');
@@ -984,10 +984,20 @@ static int rdt_last_cmd_status_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+static void *rdt_kn_parent_priv(struct kernfs_node *kn)
+{
+	/*
+	 * The parent pointer is only valid within RCU section since it can be
+	 * replaced.
+	 */
+	guard(rcu)();
+	return rcu_dereference(kn->__parent)->priv;
+}
+
 static int rdt_num_closids_show(struct kernfs_open_file *of,
 				struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 
 	seq_printf(seq, "%u\n", s->num_closid);
 	return 0;
@@ -996,7 +1006,7 @@ static int rdt_num_closids_show(struct kernfs_open_file *of,
 static int rdt_default_ctrl_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%x\n", resctrl_get_default_ctrl(r));
@@ -1006,7 +1016,7 @@ static int rdt_default_ctrl_show(struct kernfs_open_file *of,
 static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%u\n", r->cache.min_cbm_bits);
@@ -1016,7 +1026,7 @@ static int rdt_min_cbm_bits_show(struct kernfs_open_file *of,
 static int rdt_shareable_bits_show(struct kernfs_open_file *of,
 				   struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%x\n", r->cache.shareable_bits);
@@ -1040,7 +1050,7 @@ static int rdt_shareable_bits_show(struct kernfs_open_file *of,
 static int rdt_bit_usage_show(struct kernfs_open_file *of,
 			      struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	/*
 	 * Use unsigned long even though only 32 bits are used to ensure
 	 * test_bit() is used safely.
@@ -1122,7 +1132,7 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of,
 static int rdt_min_bw_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%u\n", r->membw.min_bw);
@@ -1132,7 +1142,7 @@ static int rdt_min_bw_show(struct kernfs_open_file *of,
 static int rdt_num_rmids_show(struct kernfs_open_file *of,
 			      struct seq_file *seq, void *v)
 {
-	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
 
 	seq_printf(seq, "%d\n", r->num_rmid);
 
@@ -1142,7 +1152,7 @@ static int rdt_num_rmids_show(struct kernfs_open_file *of,
 static int rdt_mon_features_show(struct kernfs_open_file *of,
 				 struct seq_file *seq, void *v)
 {
-	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
 	struct mon_evt *mevt;
 
 	list_for_each_entry(mevt, &r->evt_list, list) {
@@ -1157,7 +1167,7 @@ static int rdt_mon_features_show(struct kernfs_open_file *of,
 static int rdt_bw_gran_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%u\n", r->membw.bw_gran);
@@ -1167,7 +1177,7 @@ static int rdt_bw_gran_show(struct kernfs_open_file *of,
 static int rdt_delay_linear_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%u\n", r->membw.delay_linear);
@@ -1185,7 +1195,7 @@ static int max_threshold_occ_show(struct kernfs_open_file *of,
 static int rdt_thread_throttle_mode_show(struct kernfs_open_file *of,
 					 struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	switch (r->membw.throttle_mode) {
@@ -1259,7 +1269,7 @@ static enum resctrl_conf_type resctrl_peer_type(enum resctrl_conf_type my_type)
 static int rdt_has_sparse_bitmasks_show(struct kernfs_open_file *of,
 					struct seq_file *seq, void *v)
 {
-	struct resctrl_schema *s = of->kn->parent->priv;
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
 	struct rdt_resource *r = s->res;
 
 	seq_printf(seq, "%u\n", r->cache.arch_has_sparse_bitmasks);
@@ -1670,7 +1680,7 @@ static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid
 static int mbm_total_bytes_config_show(struct kernfs_open_file *of,
 				       struct seq_file *seq, void *v)
 {
-	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
 
 	mbm_config_show(seq, r, QOS_L3_MBM_TOTAL_EVENT_ID);
 
@@ -1680,7 +1690,7 @@ static int mbm_total_bytes_config_show(struct kernfs_open_file *of,
 static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
 				       struct seq_file *seq, void *v)
 {
-	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
 
 	mbm_config_show(seq, r, QOS_L3_MBM_LOCAL_EVENT_ID);
 
@@ -1787,7 +1797,7 @@ static ssize_t mbm_total_bytes_config_write(struct kernfs_open_file *of,
 					    char *buf, size_t nbytes,
 					    loff_t off)
 {
-	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
 	int ret;
 
 	/* Valid input requires a trailing newline */
@@ -1813,7 +1823,7 @@ static ssize_t mbm_local_bytes_config_write(struct kernfs_open_file *of,
 					    char *buf, size_t nbytes,
 					    loff_t off)
 {
-	struct rdt_resource *r = of->kn->parent->priv;
+	struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
 	int ret;
 
 	/* Valid input requires a trailing newline */
@@ -2513,12 +2523,13 @@ static struct rdtgroup *kernfs_to_rdtgroup(struct kernfs_node *kn)
 		 * resource. "info" and its subdirectories don't
 		 * have rdtgroup structures, so return NULL here.
 		 */
-		if (kn == kn_info || kn->parent == kn_info)
+		if (kn == kn_info ||
+		    rcu_access_pointer(kn->__parent) == kn_info)
 			return NULL;
 		else
 			return kn->priv;
 	} else {
-		return kn->parent->priv;
+		return rdt_kn_parent_priv(kn);
 	}
 }
 
@@ -3752,7 +3763,7 @@ out_unlock:
  */
 static bool is_mon_groups(struct kernfs_node *kn, const char *name)
 {
-	return (!strcmp(kn->name, "mon_groups") &&
+	return (!strcmp(rdt_kn_name(kn), "mon_groups") &&
 		strcmp(name, "mon_groups"));
 }
 
@@ -3867,9 +3878,18 @@ static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 	return 0;
 }
 
+static struct kernfs_node *rdt_kn_parent(struct kernfs_node *kn)
+{
+	/*
+	 * Valid within the RCU section it was obtained or while rdtgroup_mutex
+	 * is held.
+	 */