From 7d02ba96635d184dfc292ecc7308ced1fceaba8d Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:14 -0400 Subject: ref_tracker: don't use %pK in pr_ostream() output MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As Thomas Weißschuh points out [1], it is now preferable to use %p instead of hashed pointers with printk(), since raw pointers should no longer be leaked into the kernel log. Change the ref_tracker infrastructure to use %p instead of %pK in its formats. [1]: https://lore.kernel.org/netdev/20250414-restricted-pointers-net-v1-0-12af0ce46cdd@linutronix.de/ Reviewed-by: Thomas Weißschuh Reviewed-by: Krzysztof Karas Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-1-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- lib/ref_tracker.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'lib') diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index cf5609b1ca79..de71439e12a3 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -96,7 +96,7 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, stats = ref_tracker_get_stats(dir, display_limit); if (IS_ERR(stats)) { - pr_ostream(s, "%s@%pK: couldn't get stats, error %pe\n", + pr_ostream(s, "%s@%p: couldn't get stats, error %pe\n", dir->name, dir, stats); return; } @@ -107,13 +107,13 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, stack = stats->stacks[i].stack_handle; if (sbuf && !stack_depot_snprint(stack, sbuf, STACK_BUF_SIZE, 4)) sbuf[0] = 0; - pr_ostream(s, "%s@%pK has %d/%d users at\n%s\n", dir->name, dir, + pr_ostream(s, "%s@%p has %d/%d users at\n%s\n", dir->name, dir, stats->stacks[i].count, stats->total, sbuf); skipped -= stats->stacks[i].count; } if (skipped) - pr_ostream(s, "%s@%pK skipped reports about %d/%d users.\n", + pr_ostream(s, "%s@%p skipped reports about %d/%d users.\n", dir->name, dir, skipped, stats->total); kfree(sbuf); -- cgit v1.2.3 From e209f9193a4724c1d4bc0b155c7beb78aa5d2928 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:15 -0400 Subject: ref_tracker: add a top level debugfs directory for ref_tracker Add a new "ref_tracker" directory in debugfs. Each individual refcount tracker can register files under there to display info about currently-held references. Reviewed-by: Andrew Lunn Reviewed-by: Krzysztof Karas Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-2-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- lib/ref_tracker.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'lib') diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index de71439e12a3..d374e5273e14 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -273,3 +273,16 @@ int ref_tracker_free(struct ref_tracker_dir *dir, return 0; } EXPORT_SYMBOL_GPL(ref_tracker_free); + +#ifdef CONFIG_DEBUG_FS +#include + +static struct dentry *ref_tracker_debug_dir = (struct dentry *)-ENOENT; + +static int __init ref_tracker_debugfs_init(void) +{ + ref_tracker_debug_dir = debugfs_create_dir("ref_tracker", NULL); + return 0; +} +late_initcall(ref_tracker_debugfs_init); +#endif /* CONFIG_DEBUG_FS */ -- cgit v1.2.3 From 49c94af071fc6c9f5e1db52b3031dec28daa90c3 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:16 -0400 Subject: ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- include/linux/ref_tracker.h | 2 ++ lib/ref_tracker.c | 52 ++++++++++++++++++++++++++++++++------------- 2 files changed, 39 insertions(+), 15 deletions(-) (limited to 'lib') diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h index 8eac4f3d5254..a0a1ee43724f 100644 --- a/include/linux/ref_tracker.h +++ b/include/linux/ref_tracker.h @@ -6,6 +6,8 @@ #include #include +#define __ostream_printf __printf(2, 3) + struct ref_tracker; struct ref_tracker_dir { diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index d374e5273e14..42872f406b2a 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -63,21 +63,38 @@ ref_tracker_get_stats(struct ref_tracker_dir *dir, unsigned int limit) } struct ostream { + void __ostream_printf (*func)(struct ostream *stream, char *fmt, ...); + char *prefix; char *buf; int size, used; }; +static void __ostream_printf pr_ostream_log(struct ostream *stream, char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vprintk(fmt, args); + va_end(args); +} + +static void __ostream_printf pr_ostream_buf(struct ostream *stream, char *fmt, ...) +{ + int ret, len = stream->size - stream->used; + va_list args; + + va_start(args, fmt); + ret = vsnprintf(stream->buf + stream->used, len, fmt, args); + va_end(args); + if (ret > 0) + stream->used += min(ret, len); +} + #define pr_ostream(stream, fmt, args...) \ ({ \ struct ostream *_s = (stream); \ \ - if (!_s->buf) { \ - pr_err(fmt, ##args); \ - } else { \ - int ret, len = _s->size - _s->used; \ - ret = snprintf(_s->buf + _s->used, len, pr_fmt(fmt), ##args); \ - _s->used += min(ret, len); \ - } \ + _s->func(_s, fmt, ##args); \ }) static void @@ -96,8 +113,8 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, stats = ref_tracker_get_stats(dir, display_limit); if (IS_ERR(stats)) { - pr_ostream(s, "%s@%p: couldn't get stats, error %pe\n", - dir->name, dir, stats); + pr_ostream(s, "%s%s@%p: couldn't get stats, error %pe\n", + s->prefix, dir->name, dir, stats); return; } @@ -107,14 +124,15 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, stack = stats->stacks[i].stack_handle; if (sbuf && !stack_depot_snprint(stack, sbuf, STACK_BUF_SIZE, 4)) sbuf[0] = 0; - pr_ostream(s, "%s@%p has %d/%d users at\n%s\n", dir->name, dir, - stats->stacks[i].count, stats->total, sbuf); + pr_ostream(s, "%s%s@%p has %d/%d users at\n%s\n", s->prefix, + dir->name, dir, stats->stacks[i].count, + stats->total, sbuf); skipped -= stats->stacks[i].count; } if (skipped) - pr_ostream(s, "%s@%p skipped reports about %d/%d users.\n", - dir->name, dir, skipped, stats->total); + pr_ostream(s, "%s%s@%p skipped reports about %d/%d users.\n", + s->prefix, dir->name, dir, skipped, stats->total); kfree(sbuf); @@ -124,7 +142,8 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, void ref_tracker_dir_print_locked(struct ref_tracker_dir *dir, unsigned int display_limit) { - struct ostream os = {}; + struct ostream os = { .func = pr_ostream_log, + .prefix = "ref_tracker: " }; __ref_tracker_dir_pr_ostream(dir, display_limit, &os); } @@ -143,7 +162,10 @@ EXPORT_SYMBOL(ref_tracker_dir_print); int ref_tracker_dir_snprint(struct ref_tracker_dir *dir, char *buf, size_t size) { - struct ostream os = { .buf = buf, .size = size }; + struct ostream os = { .func = pr_ostream_buf, + .prefix = "ref_tracker: ", + .buf = buf, + .size = size }; unsigned long flags; spin_lock_irqsave(&dir->lock, flags); -- cgit v1.2.3 From aa7d26c3c3497258b712fb97221e775733a710b7 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:17 -0400 Subject: ref_tracker: add a static classname string to each ref_tracker_dir A later patch in the series will be adding debugfs files for each ref_tracker that get created in ref_tracker_dir_init(). The format will be "class@%px". The current "name" string can vary between ref_tracker_dir objects of the same type, so it's not suitable for this purpose. Add a new "class" string to the ref_tracker dir that describes the the type of object (sans any individual info for that object). Also, in the i915 driver, gate the creation of debugfs files on whether the dentry pointer is still set to NULL. CI has shown that the ref_tracker_dir can be initialized more than once. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-4-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- drivers/gpu/drm/display/drm_dp_tunnel.c | 2 +- drivers/gpu/drm/i915/intel_runtime_pm.c | 4 +++- drivers/gpu/drm/i915/intel_wakeref.c | 3 ++- include/linux/ref_tracker.h | 4 ++++ lib/test_ref_tracker.c | 2 +- net/core/dev.c | 2 +- net/core/net_namespace.c | 4 ++-- 7 files changed, 14 insertions(+), 7 deletions(-) (limited to 'lib') diff --git a/drivers/gpu/drm/display/drm_dp_tunnel.c b/drivers/gpu/drm/display/drm_dp_tunnel.c index 076edf161048..b9c12b8bf2a3 100644 --- a/drivers/gpu/drm/display/drm_dp_tunnel.c +++ b/drivers/gpu/drm/display/drm_dp_tunnel.c @@ -1920,7 +1920,7 @@ drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count) } #ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG - ref_tracker_dir_init(&mgr->ref_tracker, 16, "dptun"); + ref_tracker_dir_init(&mgr->ref_tracker, 16, "drm_dptun", "dptun"); #endif for (i = 0; i < max_group_count; i++) { diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index 8d9f4c410546..90d90145a189 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -59,7 +59,9 @@ static struct drm_i915_private *rpm_to_i915(struct intel_runtime_pm *rpm) static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm) { - ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT, dev_name(rpm->kdev)); + if (!rpm->debug.class) + ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT, + "intel_runtime_pm", dev_name(rpm->kdev)); } static intel_wakeref_t diff --git a/drivers/gpu/drm/i915/intel_wakeref.c b/drivers/gpu/drm/i915/intel_wakeref.c index 51561b190b93..7e74c58862c1 100644 --- a/drivers/gpu/drm/i915/intel_wakeref.c +++ b/drivers/gpu/drm/i915/intel_wakeref.c @@ -114,7 +114,8 @@ void __intel_wakeref_init(struct intel_wakeref *wf, "wakeref.work", &key->work, 0); #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_WAKEREF) - ref_tracker_dir_init(&wf->debug, INTEL_REFTRACK_DEAD_COUNT, name); + if (!wf->debug.class) + ref_tracker_dir_init(&wf->debug, INTEL_REFTRACK_DEAD_COUNT, "intel_wakeref", name); #endif } diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h index a0a1ee43724f..3968f993db81 100644 --- a/include/linux/ref_tracker.h +++ b/include/linux/ref_tracker.h @@ -19,6 +19,7 @@ struct ref_tracker_dir { bool dead; struct list_head list; /* List of active trackers */ struct list_head quarantine; /* List of dead trackers */ + const char *class; /* object classname */ char name[32]; #endif }; @@ -27,6 +28,7 @@ struct ref_tracker_dir { static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, unsigned int quarantine_count, + const char *class, const char *name) { INIT_LIST_HEAD(&dir->list); @@ -36,6 +38,7 @@ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, dir->dead = false; refcount_set(&dir->untracked, 1); refcount_set(&dir->no_tracker, 1); + dir->class = class; strscpy(dir->name, name, sizeof(dir->name)); stack_depot_init(); } @@ -60,6 +63,7 @@ int ref_tracker_free(struct ref_tracker_dir *dir, static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, unsigned int quarantine_count, + const char *class, const char *name) { } diff --git a/lib/test_ref_tracker.c b/lib/test_ref_tracker.c index b983ceb12afc..d263502a4c1d 100644 --- a/lib/test_ref_tracker.c +++ b/lib/test_ref_tracker.c @@ -64,7 +64,7 @@ static int __init test_ref_tracker_init(void) { int i; - ref_tracker_dir_init(&ref_dir, 100, "selftest"); + ref_tracker_dir_init(&ref_dir, 100, "selftest", "selftest"); timer_setup(&test_ref_tracker_timer, test_ref_tracker_timer_func, 0); mod_timer(&test_ref_tracker_timer, jiffies + 1); diff --git a/net/core/dev.c b/net/core/dev.c index be97c440ecd5..12cf4e5ae9c5 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -11715,7 +11715,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, dev->priv_len = sizeof_priv; - ref_tracker_dir_init(&dev->refcnt_tracker, 128, name); + ref_tracker_dir_init(&dev->refcnt_tracker, 128, "netdev", name); #ifdef CONFIG_PCPU_DEV_REFCNT dev->pcpu_refcnt = alloc_percpu(int); if (!dev->pcpu_refcnt) diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index ae54f26709ca..aa1e34181ed6 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -403,8 +403,8 @@ static __net_init void preinit_net(struct net *net, struct user_namespace *user_ { refcount_set(&net->passive, 1); refcount_set(&net->ns.count, 1); - ref_tracker_dir_init(&net->refcnt_tracker, 128, "net refcnt"); - ref_tracker_dir_init(&net->notrefcnt_tracker, 128, "net notrefcnt"); + ref_tracker_dir_init(&net->refcnt_tracker, 128, "net_refcnt", "net_refcnt"); + ref_tracker_dir_init(&net->notrefcnt_tracker, 128, "net_notrefcnt", "net_notrefcnt"); get_random_bytes(&net->hash_mix, sizeof(u32)); net->dev_base_seq = 1; -- cgit v1.2.3 From f6dbe294a11028db540e2dedf1929e25b1093e9b Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:18 -0400 Subject: ref_tracker: allow pr_ostream() to print directly to a seq_file Allow pr_ostream to also output directly to a seq_file without an intermediate buffer. The first caller of +ref_tracker_dir_seq_print() will come in a later patch, so mark that __maybe_unused for now. That designation will be removed once it is used. Reviewed-by: Andrew Lunn Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-5-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- lib/ref_tracker.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'lib') diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index 42872f406b2a..73b606570cce 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -8,6 +8,7 @@ #include #include #include +#include #define REF_TRACKER_STACK_ENTRIES 16 #define STACK_BUF_SIZE 1024 @@ -66,6 +67,7 @@ struct ostream { void __ostream_printf (*func)(struct ostream *stream, char *fmt, ...); char *prefix; char *buf; + struct seq_file *seq; int size, used; }; @@ -301,6 +303,30 @@ EXPORT_SYMBOL_GPL(ref_tracker_free); static struct dentry *ref_tracker_debug_dir = (struct dentry *)-ENOENT; +static void __ostream_printf pr_ostream_seq(struct ostream *stream, char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + seq_vprintf(stream->seq, fmt, args); + va_end(args); +} + +static __maybe_unused int +ref_tracker_dir_seq_print(struct ref_tracker_dir *dir, struct seq_file *seq) +{ + struct ostream os = { .func = pr_ostream_seq, + .prefix = "", + .seq = seq }; + unsigned long flags; + + spin_lock_irqsave(&dir->lock, flags); + __ref_tracker_dir_pr_ostream(dir, 16, &os); + spin_unlock_irqrestore(&dir->lock, flags); + + return os.used; +} + static int __init ref_tracker_debugfs_init(void) { ref_tracker_debug_dir = debugfs_create_dir("ref_tracker", NULL); -- cgit v1.2.3 From 65b584f5361163ba539d2c7122ca792c3cc87997 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:19 -0400 Subject: ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- include/linux/ref_tracker.h | 17 +++++ lib/ref_tracker.c | 152 ++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 164 insertions(+), 5 deletions(-) (limited to 'lib') diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h index 3968f993db81..28bbf436a8f4 100644 --- a/include/linux/ref_tracker.h +++ b/include/linux/ref_tracker.h @@ -26,6 +26,18 @@ struct ref_tracker_dir { #ifdef CONFIG_REF_TRACKER +#ifdef CONFIG_DEBUG_FS + +void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir); + +#else /* CONFIG_DEBUG_FS */ + +static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir) +{ +} + +#endif /* CONFIG_DEBUG_FS */ + static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, unsigned int quarantine_count, const char *class, @@ -40,6 +52,7 @@ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, refcount_set(&dir->no_tracker, 1); dir->class = class; strscpy(dir->name, name, sizeof(dir->name)); + ref_tracker_dir_debugfs(dir); stack_depot_init(); } @@ -68,6 +81,10 @@ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, { } +static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir) +{ +} + static inline void ref_tracker_dir_exit(struct ref_tracker_dir *dir) { } diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index 73b606570cce..c938ef56954b 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -29,6 +29,40 @@ struct ref_tracker_dir_stats { } stacks[]; }; +#ifdef CONFIG_DEBUG_FS +#include + +/* + * ref_tracker_dir_init() is usually called in allocation-safe contexts, but + * the same is not true of ref_tracker_dir_exit() which can be called from + * anywhere an object is freed. Removing debugfs dentries is a blocking + * operation, so we defer that work to the debugfs_reap_worker. + * + * Each dentry is tracked in the appropriate xarray. When + * ref_tracker_dir_exit() is called, its entries in the xarrays are marked and + * the workqueue job is scheduled. The worker then runs and deletes any marked + * dentries asynchronously. + */ +static struct xarray debugfs_dentries; +static struct work_struct debugfs_reap_worker; + +#define REF_TRACKER_DIR_DEAD XA_MARK_0 +static inline void ref_tracker_debugfs_mark(struct ref_tracker_dir *dir) +{ + unsigned long flags; + + xa_lock_irqsave(&debugfs_dentries, flags); + __xa_set_mark(&debugfs_dentries, (unsigned long)dir, REF_TRACKER_DIR_DEAD); + xa_unlock_irqrestore(&debugfs_dentries, flags); + + schedule_work(&debugfs_reap_worker); +} +#else +static inline void ref_tracker_debugfs_mark(struct ref_tracker_dir *dir) +{ +} +#endif + static struct ref_tracker_dir_stats * ref_tracker_get_stats(struct ref_tracker_dir *dir, unsigned int limit) { @@ -185,6 +219,11 @@ void ref_tracker_dir_exit(struct ref_tracker_dir *dir) bool leak = false; dir->dead = true; + /* + * The xarray entries must be marked before the dir->lock is taken to + * protect simultaneous debugfs readers. + */ + ref_tracker_debugfs_mark(dir); spin_lock_irqsave(&dir->lock, flags); list_for_each_entry_safe(tracker, n, &dir->quarantine, head) { list_del(&tracker->head); @@ -312,23 +351,126 @@ static void __ostream_printf pr_ostream_seq(struct ostream *stream, char *fmt, . va_end(args); } -static __maybe_unused int -ref_tracker_dir_seq_print(struct ref_tracker_dir *dir, struct seq_file *seq) +static int ref_tracker_dir_seq_print(struct ref_tracker_dir *dir, struct seq_file *seq) { struct ostream os = { .func = pr_ostream_seq, .prefix = "", .seq = seq }; - unsigned long flags; - spin_lock_irqsave(&dir->lock, flags); __ref_tracker_dir_pr_ostream(dir, 16, &os); - spin_unlock_irqrestore(&dir->lock, flags); return os.used; } +static int ref_tracker_debugfs_show(struct seq_file *f, void *v) +{ + struct ref_tracker_dir *dir = f->private; + unsigned long index = (unsigned long)dir; + unsigned long flags; + int ret; + + /* + * "dir" may not exist at this point if ref_tracker_dir_exit() has + * already been called. Take care not to dereference it until its + * legitimacy is established. + * + * The xa_lock is necessary to ensure that "dir" doesn't disappear + * before its lock can be taken. If it's in the hash and not marked + * dead, then it's safe to take dir->lock which prevents + * ref_tracker_dir_exit() from completing. Once the dir->lock is + * acquired, the xa_lock can be released. All of this must be IRQ-safe. + */ + xa_lock_irqsave(&debugfs_dentries, flags); + if (!xa_load(&debugfs_dentries, index) || + xa_get_mark(&debugfs_dentries, index, REF_TRACKER_DIR_DEAD)) { + xa_unlock_irqrestore(&debugfs_dentries, flags); + return -ENODATA; + } + + spin_lock(&dir->lock); + xa_unlock(&debugfs_dentries); + ret = ref_tracker_dir_seq_print(dir, f); + spin_unlock_irqrestore(&dir->lock, flags); + return ret; +} + +static int ref_tracker_debugfs_open(struct inode *inode, struct file *filp) +{ + struct ref_tracker_dir *dir = inode->i_private; + + return single_open(filp, ref_tracker_debugfs_show, dir); +} + +static const struct file_operations ref_tracker_debugfs_fops = { + .owner = THIS_MODULE, + .open = ref_tracker_debugfs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/** + * ref_tracker_dir_debugfs - create debugfs file for ref_tracker_dir + * @dir: ref_tracker_dir to be associated with debugfs file + * + * In most cases, a debugfs file will be created automatically for every + * ref_tracker_dir. If the object was created before debugfs is brought up + * then that may fail. In those cases, it is safe to call this at a later + * time to create the file. + */ +void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir) +{ + char name[NAME_MAX + 1]; + struct dentry *dentry; + int ret; + + /* No-op if already created */ + dentry = xa_load(&debugfs_dentries, (unsigned long)dir); + if (dentry && !xa_is_err(dentry)) + return; + + ret = snprintf(name, sizeof(name), "%s@%px", dir->class, dir); + name[sizeof(name) - 1] = '\0'; + + if (ret < sizeof(name)) { + dentry = debugfs_create_file(name, S_IFREG | 0400, + ref_tracker_debug_dir, dir, + &ref_tracker_debugfs_fops); + if (!IS_ERR(dentry)) { + void *old; + + old = xa_store_irq(&debugfs_dentries, (unsigned long)dir, + dentry, GFP_KERNEL); + + if (xa_is_err(old)) + debugfs_remove(dentry); + else + WARN_ON_ONCE(old); + } + } +} +EXPORT_SYMBOL(ref_tracker_dir_debugfs); + +static void debugfs_reap_work(struct work_struct *work) +{ + struct dentry *dentry; + unsigned long index; + bool reaped; + + do { + reaped = false; + xa_for_each_marked(&debugfs_dentries, index, dentry, REF_TRACKER_DIR_DEAD) { + xa_erase_irq(&debugfs_dentries, index); + debugfs_remove(dentry); + reaped = true; + } + } while (reaped); +} + static int __init ref_tracker_debugfs_init(void) { + INIT_WORK(&debugfs_reap_worker, debugfs_reap_work); + xa_init_flags(&debugfs_dentries, XA_FLAGS_LOCK_IRQ); ref_tracker_debug_dir = debugfs_create_dir("ref_tracker", NULL); return 0; } -- cgit v1.2.3 From d04992dc86a6c77b7d39a1ee10013aed7111e855 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:20 -0400 Subject: ref_tracker: add a way to create a symlink to the ref_tracker_dir debugfs file Add the ability for a subsystem to add a user-friendly symlink that points to a ref_tracker_dir's debugfs file. Add a separate debugfs_symlinks xarray and use that to track symlinks. The reaper workqueue job will remove symlinks before their corresponding dentries. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-7-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- include/linux/ref_tracker.h | 11 ++++++++++ lib/ref_tracker.c | 50 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 61 insertions(+) (limited to 'lib') diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h index 28bbf436a8f4..e1323de93bf6 100644 --- a/include/linux/ref_tracker.h +++ b/include/linux/ref_tracker.h @@ -29,6 +29,7 @@ struct ref_tracker_dir { #ifdef CONFIG_DEBUG_FS void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir); +void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...); #else /* CONFIG_DEBUG_FS */ @@ -36,6 +37,11 @@ static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir) { } +static inline __ostream_printf +void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...) +{ +} + #endif /* CONFIG_DEBUG_FS */ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, @@ -85,6 +91,11 @@ static inline void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir) { } +static inline __ostream_printf +void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...) +{ +} + static inline void ref_tracker_dir_exit(struct ref_tracker_dir *dir) { } diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index c938ef56954b..6608520d6118 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -44,6 +44,7 @@ struct ref_tracker_dir_stats { * dentries asynchronously. */ static struct xarray debugfs_dentries; +static struct xarray debugfs_symlinks; static struct work_struct debugfs_reap_worker; #define REF_TRACKER_DIR_DEAD XA_MARK_0 @@ -55,6 +56,10 @@ static inline void ref_tracker_debugfs_mark(struct ref_tracker_dir *dir) __xa_set_mark(&debugfs_dentries, (unsigned long)dir, REF_TRACKER_DIR_DEAD); xa_unlock_irqrestore(&debugfs_dentries, flags); + xa_lock_irqsave(&debugfs_symlinks, flags); + __xa_set_mark(&debugfs_symlinks, (unsigned long)dir, REF_TRACKER_DIR_DEAD); + xa_unlock_irqrestore(&debugfs_symlinks, flags); + schedule_work(&debugfs_reap_worker); } #else @@ -451,6 +456,45 @@ void ref_tracker_dir_debugfs(struct ref_tracker_dir *dir) } EXPORT_SYMBOL(ref_tracker_dir_debugfs); +void __ostream_printf ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...) +{ + char name[NAME_MAX + 1]; + struct dentry *symlink, *dentry; + va_list args; + int ret; + + symlink = xa_load(&debugfs_symlinks, (unsigned long)dir); + dentry = xa_load(&debugfs_dentries, (unsigned long)dir); + + /* Already created?*/ + if (symlink && !xa_is_err(symlink)) + return; + + if (!dentry || xa_is_err(dentry)) + return; + + va_start(args, fmt); + ret = vsnprintf(name, sizeof(name), fmt, args); + va_end(args); + name[sizeof(name) - 1] = '\0'; + + if (ret < sizeof(name)) { + symlink = debugfs_create_symlink(name, ref_tracker_debug_dir, + dentry->d_name.name); + if (!IS_ERR(symlink)) { + void *old; + + old = xa_store_irq(&debugfs_symlinks, (unsigned long)dir, + symlink, GFP_KERNEL); + if (xa_is_err(old)) + debugfs_remove(symlink); + else + WARN_ON_ONCE(old); + } + } +} +EXPORT_SYMBOL(ref_tracker_dir_symlink); + static void debugfs_reap_work(struct work_struct *work) { struct dentry *dentry; @@ -459,6 +503,11 @@ static void debugfs_reap_work(struct work_struct *work) do { reaped = false; + xa_for_each_marked(&debugfs_symlinks, index, dentry, REF_TRACKER_DIR_DEAD) { + xa_erase_irq(&debugfs_symlinks, index); + debugfs_remove(dentry); + reaped = true; + } xa_for_each_marked(&debugfs_dentries, index, dentry, REF_TRACKER_DIR_DEAD) { xa_erase_irq(&debugfs_dentries, index); debugfs_remove(dentry); @@ -471,6 +520,7 @@ static int __init ref_tracker_debugfs_init(void) { INIT_WORK(&debugfs_reap_worker, debugfs_reap_work); xa_init_flags(&debugfs_dentries, XA_FLAGS_LOCK_IRQ); + xa_init_flags(&debugfs_symlinks, XA_FLAGS_LOCK_IRQ); ref_tracker_debug_dir = debugfs_create_dir("ref_tracker", NULL); return 0; } -- cgit v1.2.3 From 707bd05be75f65749c3f1695f4e362a89b3fcc7b Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Wed, 18 Jun 2025 10:24:22 -0400 Subject: ref_tracker: eliminate the ref_tracker_dir name field Now that we have dentries and the ability to create meaningful symlinks to them, don't keep a name string in each tracker. Switch the output format to print "class@address", and drop the name field. Also, add a kerneldoc header for ref_tracker_dir_init(). Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-9-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski --- drivers/gpu/drm/display/drm_dp_tunnel.c | 2 +- drivers/gpu/drm/i915/intel_runtime_pm.c | 2 +- drivers/gpu/drm/i915/intel_wakeref.c | 2 +- include/linux/ref_tracker.h | 20 ++++++++++++++------ lib/ref_tracker.c | 6 +++--- lib/test_ref_tracker.c | 2 +- net/core/dev.c | 2 +- net/core/net_namespace.c | 4 ++-- 8 files changed, 24 insertions(+), 16 deletions(-) (limited to 'lib') diff --git a/drivers/gpu/drm/display/drm_dp_tunnel.c b/drivers/gpu/drm/display/drm_dp_tunnel.c index b9c12b8bf2a3..1205a4432eb4 100644 --- a/drivers/gpu/drm/display/drm_dp_tunnel.c +++ b/drivers/gpu/drm/display/drm_dp_tunnel.c @@ -1920,7 +1920,7 @@ drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count) } #ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG - ref_tracker_dir_init(&mgr->ref_tracker, 16, "drm_dptun", "dptun"); + ref_tracker_dir_init(&mgr->ref_tracker, 16, "drm_dptun"); #endif for (i = 0; i < max_group_count; i++) { diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index 90d90145a189..7ce3e6de0c19 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -61,7 +61,7 @@ static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm) { if (!rpm->debug.class) ref_tracker_dir_init(&rpm->debug, INTEL_REFTRACK_DEAD_COUNT, - "intel_runtime_pm", dev_name(rpm->kdev)); + "intel_runtime_pm"); } static intel_wakeref_t diff --git a/drivers/gpu/drm/i915/intel_wakeref.c b/drivers/gpu/drm/i915/intel_wakeref.c index 7e74c58862c1..7fa194de5d35 100644 --- a/drivers/gpu/drm/i915/intel_wakeref.c +++ b/drivers/gpu/drm/i915/intel_wakeref.c @@ -115,7 +115,7 @@ void __intel_wakeref_init(struct intel_wakeref *wf, #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_WAKEREF) if (!wf->debug.class) - ref_tracker_dir_init(&wf->debug, INTEL_REFTRACK_DEAD_COUNT, "intel_wakeref", name); + ref_tracker_dir_init(&wf->debug, INTEL_REFTRACK_DEAD_COUNT, "intel_wakeref"); #endif } diff --git a/include/linux/ref_tracker.h b/include/linux/ref_tracker.h index e1323de93bf6..d10563afd91c 100644 --- a/include/linux/ref_tracker.h +++ b/include/linux/ref_tracker.h @@ -20,7 +20,6 @@ struct ref_tracker_dir { struct list_head list; /* List of active trackers */ struct list_head quarantine; /* List of dead trackers */ const char *class; /* object classname */ - char name[32]; #endif }; @@ -44,10 +43,21 @@ void ref_tracker_dir_symlink(struct ref_tracker_dir *dir, const char *fmt, ...) #endif /* CONFIG_DEBUG_FS */ +/** + * ref_tracker_dir_init - initialize a ref_tracker dir + * @dir: ref_tracker_dir to be initialized + * @quarantine_count: max number of entries to be tracked + * @class: pointer to static string that describes object type + * + * Initialize a ref_tracker_dir. If debugfs is configured, then a file + * will also be created for it under the top-level ref_tracker debugfs + * directory. + * + * Note that @class must point to a static string. + */ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, unsigned int quarantine_count, - const char *class, - const char *name) + const char *class) { INIT_LIST_HEAD(&dir->list); INIT_LIST_HEAD(&dir->quarantine); @@ -57,7 +67,6 @@ static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, refcount_set(&dir->untracked, 1); refcount_set(&dir->no_tracker, 1); dir->class = class; - strscpy(dir->name, name, sizeof(dir->name)); ref_tracker_dir_debugfs(dir); stack_depot_init(); } @@ -82,8 +91,7 @@ int ref_tracker_free(struct ref_tracker_dir *dir, static inline void ref_tracker_dir_init(struct ref_tracker_dir *dir, unsigned int quarantine_count, - const char *class, - const char *name) + const char *class) { } diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index 6608520d6118..dcf923a1edf5 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -155,7 +155,7 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, stats = ref_tracker_get_stats(dir, display_limit); if (IS_ERR(stats)) { pr_ostream(s, "%s%s@%p: couldn't get stats, error %pe\n", - s->prefix, dir->name, dir, stats); + s->prefix, dir->class, dir, stats); return; } @@ -166,14 +166,14 @@ __ref_tracker_dir_pr_ostream(struct ref_tracker_dir *dir, if (sbuf && !stack_depot_snprint(stack, sbuf, STACK_BUF_SIZE, 4)) sbuf[0] = 0; pr_ostream(s, "%s%s@%p has %d/%d users at\n%s\n", s->prefix, - dir->name, dir, stats->stacks[i].count, + dir->class, dir, stats->stacks[i].count, stats->total, sbuf); skipped -= stats->stacks[i].count; } if (skipped) pr_ostream(s, "%s%s@%p skipped reports about %d/%d users.\n", - s->prefix, dir->name, dir, skipped, stats->total); + s->prefix, dir->class, dir, skipped, stats->total); kfree(sbuf); diff --git a/lib/test_ref_tracker.c b/lib/test_ref_tracker.c index d263502a4c1d..b983ceb12afc 100644 --- a/lib/test_ref_tracker.c +++ b/lib/test_ref_tracker.c @@ -64,7 +64,7 @@ static int __init test_ref_tracker_init(void) { int i; - ref_tracker_dir_init(&ref_dir, 100, "selftest", "selftest"); + ref_tracker_dir_init(&ref_dir, 100, "selftest"); timer_setup(&test_ref_tracker_timer, test_ref_tracker_timer_func, 0); mod_timer(&test_ref_tracker_timer, jiffies + 1); diff --git a/net/core/dev.c b/net/core/dev.c index 12cf4e5ae9c5..92a830162dd8 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -11715,7 +11715,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, dev->priv_len = sizeof_priv; - ref_tracker_dir_init(&dev->refcnt_tracker, 128, "netdev", name); + ref_tracker_dir_init(&dev->refcnt_tracker, 128, "netdev"); #ifdef CONFIG_PCPU_DEV_REFCNT dev->pcpu_refcnt = alloc_percpu(int); if (!dev->pcpu_refcnt) diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 45de05d8f087..d0f607507ee8 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -403,8 +403,8 @@ static __net_init void preinit_net(struct net *net, struct user_namespace *user_ { refcount_set(&net->passive, 1); refcount_set(&net->ns.count, 1); - ref_tracker_dir_init(&net->refcnt_tracker, 128, "net_refcnt", "net_refcnt"); - ref_tracker_dir_init(&net->notrefcnt_tracker, 128, "net_notrefcnt", "net_notrefcnt"); + ref_tracker_dir_init(&net->refcnt_tracker, 128, "net_refcnt"); + ref_tracker_dir_init(&net->notrefcnt_tracker, 128, "net_notrefcnt"); get_random_bytes(&net->hash_mix, sizeof(u32)); net->dev_base_seq = 1; -- cgit v1.2.3 From 7df6c0245595871500758c4cfa6052081e6687c9 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 20 Jun 2025 13:19:04 +0200 Subject: lib: test_objagg: split test_hints_case() into two functions With sanitizers enabled, this function uses a lot of stack, causing a harmless warning: lib/test_objagg.c: In function 'test_hints_case.constprop': lib/test_objagg.c:994:1: error: the frame size of 1440 bytes is larger than 1408 bytes [-Werror=frame-larger-than=] Most of this is from the two 'struct world' structures. Since most of the work in this function is duplicated for the two, split it up into separate functions that each use one of them. The combined stack usage is still the same here, but there is no warning any more, and the code is still safe because of the known call chain. Signed-off-by: Arnd Bergmann Link: https://patch.msgid.link/20250620111907.3395296-1-arnd@kernel.org Signed-off-by: Jakub Kicinski --- lib/test_objagg.c | 77 ++++++++++++++++++++++++++++++++----------------------- 1 file changed, 45 insertions(+), 32 deletions(-) (limited to 'lib') diff --git a/lib/test_objagg.c b/lib/test_objagg.c index d34df4306b87..a67b8ef5c5be 100644 --- a/lib/test_objagg.c +++ b/lib/test_objagg.c @@ -906,50 +906,22 @@ static int check_expect_hints_stats(struct objagg_hints *objagg_hints, return err; } -static int test_hints_case(const struct hints_case *hints_case) +static int test_hints_case2(const struct hints_case *hints_case, + struct objagg_hints *hints, struct objagg *objagg) { struct objagg_obj *objagg_obj; - struct objagg_hints *hints; struct world world2 = {}; - struct world world = {}; struct objagg *objagg2; - struct objagg *objagg; const char *errmsg; int i; int err; - objagg = objagg_create(&delta_ops, NULL, &world); - if (IS_ERR(objagg)) - return PTR_ERR(objagg); - - for (i = 0; i < hints_case->key_ids_count; i++) { - objagg_obj = world_obj_get(&world, objagg, - hints_case->key_ids[i]); - if (IS_ERR(objagg_obj)) { - err = PTR_ERR(objagg_obj); - goto err_world_obj_get; - } - } - - pr_debug_stats(objagg); - err = check_expect_stats(objagg, &hints_case->expect_stats, &errmsg); - if (err) { - pr_err("Stats: %s\n", errmsg); - goto err_check_expect_stats; - } - - hints = objagg_hints_get(objagg, OBJAGG_OPT_ALGO_SIMPLE_GREEDY); - if (IS_ERR(hints)) { - err = PTR_ERR(hints); - goto err_hints_get; - } - pr_debug_hints_stats(hints); err = check_expect_hints_stats(hints, &hints_case->expect_stats_hints, &errmsg); if (err) { pr_err("Hints stats: %s\n", errmsg); - goto err_check_expect_hints_stats; + return err; } objagg2 = objagg_create(&delta_ops, hints, &world2); @@ -981,7 +953,48 @@ err_world2_obj_get: world_obj_put(&world2, objagg, hints_case->key_ids[i]); i = hints_case->key_ids_count; objagg_destroy(objagg2); -err_check_expect_hints_stats: + + return err; +} + +static int test_hints_case(const struct hints_case *hints_case) +{ + struct objagg_obj *objagg_obj; + struct objagg_hints *hints; + struct world world = {}; + struct objagg *objagg; + const char *errmsg; + int i; + int err; + + objagg = objagg_create(&delta_ops, NULL, &world); + if (IS_ERR(objagg)) + return PTR_ERR(objagg); + + for (i = 0; i < hints_case->key_ids_count; i++) { + objagg_obj = world_obj_get(&world, objagg, + hints_case->key_ids[i]); + if (IS_ERR(objagg_obj)) { + err = PTR_ERR(objagg_obj); + goto err_world_obj_get; + } + } + + pr_debug_stats(objagg); + err = check_expect_stats(objagg, &hints_case->expect_stats, &errmsg); + if (err) { + pr_err("Stats: %s\n", errmsg); + goto err_check_expect_stats; + } + + hints = objagg_hints_get(objagg, OBJAGG_OPT_ALGO_SIMPLE_GREEDY); + if (IS_ERR(hints)) { + err = PTR_ERR(hints); + goto err_hints_get; + } + + err = test_hints_case2(hints_case, hints, objagg); + objagg_hints_put(hints); err_hints_get: err_check_expect_stats: -- cgit v1.2.3 From f4e6aefb9c6d8f9a5baa2a26bddaff4fbb4d280e Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 26 Jun 2025 08:52:14 -0400 Subject: ref_tracker: do xarray and workqueue job initializations earlier The kernel test robot reported an oops that occurred when attempting to deregister a dentry from the xarray during subsys_initcall(). The ref_tracker xarrays and workqueue job are being initialized in late_initcall() which is too late. Move those to postcore_initcall() instead. Fixes: 65b584f53611 ("ref_tracker: automatically register a file in debugfs for a ref_tracker_dir") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202506251406.c28f2adb-lkp@intel.com Signed-off-by: Jeff Layton Signed-off-by: Jakub Kicinski Link: https://patch.msgid.link/20250626-reftrack-dbgfs-v1-1-812102e2a394@kernel.org --- lib/ref_tracker.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c index dcf923a1edf5..a9e6ffcff04b 100644 --- a/lib/ref_tracker.c +++ b/lib/ref_tracker.c @@ -516,13 +516,19 @@ static void debugfs_reap_work(struct work_struct *work) } while (reaped); } -static int __init ref_tracker_debugfs_init(void) +static int __init ref_tracker_debugfs_postcore_init(void) { INIT_WORK(&debugfs_reap_worker, debugfs_reap_work); xa_init_flags(&debugfs_dentries, XA_FLAGS_LOCK_IRQ); xa_init_flags(&debugfs_symlinks, XA_FLAGS_LOCK_IRQ); + return 0; +} +postcore_initcall(ref_tracker_debugfs_postcore_init); + +static int __init ref_tracker_debugfs_late_init(void) +{ ref_tracker_debug_dir = debugfs_create_dir("ref_tracker", NULL); return 0; } -late_initcall(ref_tracker_debugfs_init); +late_initcall(ref_tracker_debugfs_late_init); #endif /* CONFIG_DEBUG_FS */ -- cgit v1.2.3