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authorLinus Torvalds <torvalds@linux-foundation.org>2025-07-30 08:58:55 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2025-07-30 08:58:55 -0700
commit8be4d31cb8aaeea27bde4b7ddb26e28a89062ebf (patch)
treefec3039a08284cd87f4ec9c3bea5b5a439f1859f /lib/ref_tracker.c
parent4b290aae788e06561754b28c6842e4080957d3f7 (diff)
parentfa582ca7e187a15e772e6a72fe035f649b387a60 (diff)
Merge tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski: "Core & protocols: - Wrap datapath globals into net_aligned_data, to avoid false sharing - Preserve MSG_ZEROCOPY in forwarding (e.g. out of a container) - Add SO_INQ and SCM_INQ support to AF_UNIX - Add SIOCINQ support to AF_VSOCK - Add TCP_MAXSEG sockopt to MPTCP - Add IPv6 force_forwarding sysctl to enable forwarding per interface - Make TCP validation of whether packet fully fits in the receive window and the rcv_buf more strict. With increased use of HW aggregation a single "packet" can be multiple 100s of kB - Add MSG_MORE flag to optimize large TCP transmissions via sockmap, improves latency up to 33% for sockmap users - Convert TCP send queue handling from tasklet to BH workque - Improve BPF iteration over TCP sockets to see each socket exactly once - Remove obsolete and unused TCP RFC3517/RFC6675 loss recovery code - Support enabling kernel threads for NAPI processing on per-NAPI instance basis rather than a whole device. Fully stop the kernel NAPI thread when threaded NAPI gets disabled. Previously thread would stick around until ifdown due to tricky synchronization - Allow multicast routing to take effect on locally-generated packets - Add output interface argument for End.X in segment routing - MCTP: add support for gateway routing, improve bind() handling - Don't require rtnl_lock when fetching an IPv6 neighbor over Netlink - Add a new neighbor flag ("extern_valid"), which cedes refresh responsibilities to userspace. This is needed for EVPN multi-homing where a neighbor entry for a multi-homed host needs to be synced across all the VTEPs among which the host is multi-homed - Support NUD_PERMANENT for proxy neighbor entries - Add a new queuing discipline for IETF RFC9332 DualQ Coupled AQM - Add sequence numbers to netconsole messages. Unregister netconsole's console when all net targets are removed. Code refactoring. Add a number of selftests - Align IPSec inbound SA lookup to RFC 4301. Only SPI and protocol should be used for an inbound SA lookup - Support inspecting ref_tracker state via DebugFS - Don't force bonding advertisement frames tx to ~333 ms boundaries. Add broadcast_neighbor option to send ARP/ND on all bonded links - Allow providing upcall pid for the 'execute' command in openvswitch - Remove DCCP support from Netfilter's conntrack - Disallow multiple packet duplications in the queuing layer - Prevent use of deprecated iptables code on PREEMPT_RT Driver API: - Support RSS and hashing configuration over ethtool Netlink - Add dedicated ethtool callbacks for getting and setting hashing fields - Add support for power budget evaluation strategy in PSE / Power-over-Ethernet. Generate Netlink events for overcurrent etc - Support DPLL phase offset monitoring across all device inputs. Support providing clock reference and SYNC over separate DPLL inputs - Support traffic classes in devlink rate API for bandwidth management - Remove rtnl_lock dependency from UDP tunnel port configuration Device drivers: - Add a new Broadcom driver for 800G Ethernet (bnge) - Add a standalone driver for Microchip ZL3073x DPLL - Remove IBM's NETIUCV device driver - Ethernet high-speed NICs: - Broadcom (bnxt): - support zero-copy Tx of DMABUF memory - take page size into account for page pool recycling rings - Intel (100G, ice, idpf): - idpf: XDP and AF_XDP support preparations - idpf: add flow steering - add link_down_events statistic - clean up the TSPLL code - preparations for live VM migration - nVidia/Mellanox: - support zero-copy Rx/Tx interfaces (DMABUF and io_uring) - optimize context memory usage for matchers - expose serial numbers in devlink info - support PCIe congestion metrics - Meta (fbnic): - add 25G, 50G, and 100G link modes to phylink - support dumping FW logs - Marvell/Cavium: - support for CN20K generation of the Octeon chips - Amazon: - add HW clock (without timestamping, just hypervisor time access) - Ethernet virtual: - VirtIO net: - support segmentation of UDP-tunnel-encapsulated packets - Google (gve): - support packet timestamping and clock synchronization - Microsoft vNIC: - add handler for device-originated servicing events - allow dynamic MSI-X vector allocation - support Tx bandwidth clamping - Ethernet NICs consumer, and embedded: - AMD: - amd-xgbe: hardware timestamping and PTP clock support - Broadcom integrated MACs (bcmgenet, bcmasp): - use napi_complete_done() return value to support NAPI polling - add support for re-starting auto-negotiation - Broadcom switches (b53): - support BCM5325 switches - add bcm63xx EPHY power control - Synopsys (stmmac): - lots of code refactoring and cleanups - TI: - icssg-prueth: read firmware-names from device tree - icssg: PRP offload support - Microchip: - lan78xx: convert to PHYLINK for improved PHY and MAC management - ksz: add KSZ8463 switch support - Intel: - support similar queue priority scheme in multi-queue and time-sensitive networking (taprio) - support packet pre-emption in both - RealTek (r8169): - enable EEE at 5Gbps on RTL8126 - Airoha: - add PPPoE offload support - MDIO bus controller for Airoha AN7583 - Ethernet PHYs: - support for the IPQ5018 internal GE PHY - micrel KSZ9477 switch-integrated PHYs: - add MDI/MDI-X control support - add RX error counters - add cable test support - add Signal Quality Indicator (SQI) reporting - dp83tg720: improve reset handling and reduce link recovery time - support bcm54811 (and its MII-Lite interface type) - air_en8811h: support resume/suspend - support PHY counters for QCA807x and QCA808x - support WoL for QCA807x - CAN drivers: - rcar_canfd: support for Transceiver Delay Compensation - kvaser: report FW versions via devlink dev info - WiFi: - extended regulatory info support (6 GHz) - add statistics and beacon monitor for Multi-Link Operation (MLO) - support S1G aggregation, improve S1G support - add Radio Measurement action fields - support per-radio RTS threshold - some work around how FIPS affects wifi, which was wrong (RC4 is used by TKIP, not only WEP) - improvements for unsolicited probe response handling - WiFi drivers: - RealTek (rtw88): - IBSS mode for SDIO devices - RealTek (rtw89): - BT coexistence for MLO/WiFi7 - concurrent station + P2P support - support for USB devices RTL8851BU/RTL8852BU - Intel (iwlwifi): - use embedded PNVM in (to be released) FW images to fix compatibility issues - many cleanups (unused FW APIs, PCIe code, WoWLAN) - some FIPS interoperability - MediaTek (mt76): - firmware recovery improvements - more MLO work - Qualcomm/Atheros (ath12k): - fix scan on multi-radio devices - more EHT/Wi-Fi 7 features - encapsulation/decapsulation offload - Broadcom (brcm80211): - support SDIO 43751 device - Bluetooth: - hci_event: add support for handling LE BIG Sync Lost event - ISO: add socket option to report packet seqnum via CMSG - ISO: support SCM_TIMESTAMPING for ISO TS - Bluetooth drivers: - intel_pcie: support Function Level Reset - nxpuart: add support for 4M baudrate - nxpuart: implement powerup sequence, reset, FW dump, and FW loading" * tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1742 commits) dpll: zl3073x: Fix build failure selftests: bpf: fix legacy netfilter options ipv6: annotate data-races around rt->fib6_nsiblings ipv6: fix possible infinite loop in fib6_info_uses_dev() ipv6: prevent infinite loop in rt6_nlmsg_size() ipv6: add a retry logic in net6_rt_notify() vrf: Drop existing dst reference in vrf_ip6_input_dst net/sched: taprio: align entry index attr validation with mqprio net: fsl_pq_mdio: use dev_err_probe selftests: rtnetlink.sh: remove esp4_offload after test vsock: remove unnecessary null check in vsock_getname() igb: xsk: solve negative overflow of nb_pkts in zerocopy mode stmmac: xsk: fix negative overflow of budget in zerocopy mode dt-bindings: ieee802154: Convert at86rf230.txt yaml format net: dsa: microchip: Disable PTP function of KSZ8463 net: dsa: microchip: Setup fiber ports for KSZ8463 net: dsa: microchip: Write switch MAC address differently for KSZ8463 net: dsa: microchip: Use different registers for KSZ8463 net: dsa: microchip: Add KSZ8463 switch support to KSZ DSA driver dt-bindings: net: dsa: microchip: Add KSZ8463 switch support ...
Diffstat (limited to 'lib/ref_tracker.c')
-rw-r--r--lib/ref_tracker.c289
1 files changed, 274 insertions, 15 deletions
diff --git a/lib/ref_tracker.c b/lib/ref_tracker.c
index cf5609b1ca79..a9e6ffcff04b 100644
--- a/lib/ref_tracker.c
+++ b/lib/ref_tracker.c
@@ -8,6 +8,7 @@
#include <linux/slab.h>
#include <linux/stacktrace.h>
#include <linux/stackdepot.h>
+#include <linux/seq_file.h>
#define REF_TRACKER_STACK_ENTRIES 16
#define STACK_BUF_SIZE 1024
@@ -28,6 +29,45 @@ struct ref_tracker_dir_stats {
} stacks[];
};
+#ifdef CONFIG_DEBUG_FS
+#include <linux/xarray.h>
+
+/*
+ * 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 xarray debugfs_symlinks;
+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);
+
+ 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
+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)
{
@@ -63,21 +103,39 @@ 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;
+ struct seq_file *seq;
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 +154,8 @@ __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@%pK: 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->class, dir, stats);
return;
}
@@ -107,14 +165,15 @@ __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@%pK 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->class, 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",
- dir->name, dir, skipped, stats->total);
+ pr_ostream(s, "%s%s@%p skipped reports about %d/%d users.\n",
+ s->prefix, dir->class, dir, skipped, stats->total);
kfree(sbuf);
@@ -124,7 +183,8 @@ __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 +203,10 @@ 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);
@@ -161,6 +224,11 @@ 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);
@@ -273,3 +341,194 @@ int ref_tracker_free(struct ref_tracker_dir *dir,
return 0;
}
EXPORT_SYMBOL_GPL(ref_tracker_free);
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+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 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 };
+
+ __ref_tracker_dir_pr_ostream(dir, 16, &os);
+
+ 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);
+
+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;
+ unsigned long index;
+ bool reaped;
+
+ 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);
+ reaped = true;
+ }
+ } while (reaped);
+}
+
+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_late_init);
+#endif /* CONFIG_DEBUG_FS */