Daniel Borkmann says:

====================
pull-request: bpf-next 2023-02-11

We've added 96 non-merge commits during the last 14 day(s) which contain
a total of 152 files changed, 4884 insertions(+), 962 deletions(-).

There is a minor conflict in drivers/net/ethernet/intel/ice/ice_main.c
between commit 5b246e533d01 ("ice: split probe into smaller functions")
from the net-next tree and commit 66c0e13ad236 ("drivers: net: turn on
XDP features") from the bpf-next tree. Remove the hunk given ice_cfg_netdev()
is otherwise there a 2nd time, and add XDP features to the existing
ice_cfg_netdev() one:

        [...]
        ice_set_netdev_features(netdev);
        netdev->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT |
                               NETDEV_XDP_ACT_XSK_ZEROCOPY;
        ice_set_ops(netdev);
        [...]

Stephen's merge conflict mail:
https://lore.kernel.org/bpf/20230207101951.21a114fa@canb.auug.org.au/

The main changes are:

1) Add support for BPF trampoline on s390x which finally allows to remove many
   test cases from the BPF CI's DENYLIST.s390x, from Ilya Leoshkevich.

2) Add multi-buffer XDP support to ice driver, from Maciej Fijalkowski.

3) Add capability to export the XDP features supported by the NIC.
   Along with that, add a XDP compliance test tool,
   from Lorenzo Bianconi & Marek Majtyka.

4) Add __bpf_kfunc tag for marking kernel functions as kfuncs,
   from David Vernet.

5) Add a deep dive documentation about the verifier's register
   liveness tracking algorithm, from Eduard Zingerman.

6) Fix and follow-up cleanups for resolve_btfids to be compiled
   as a host program to avoid cross compile issues,
   from Jiri Olsa & Ian Rogers.

7) Batch of fixes to the BPF selftest for xdp_hw_metadata which resulted
   when testing on different NICs, from Jesper Dangaard Brouer.

8) Fix libbpf to better detect kernel version code on Debian, from Hao Xiang.

9) Extend libbpf to add an option for when the perf buffer should
   wake up, from Jon Doron.

10) Follow-up fix on xdp_metadata selftest to just consume on TX
    completion, from Stanislav Fomichev.

11) Extend the kfuncs.rst document with description on kfunc
    lifecycle & stability expectations, from David Vernet.

12) Fix bpftool prog profile to skip attaching to offline CPUs,
    from Tonghao Zhang.

====================

Link: https://lore.kernel.org/r/20230211002037.8489-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

6 files changed, 109 insertions, 8 deletions

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f7f24defccb8..35c18a98c21a 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -899,8 +899,12 @@ enum bpf_cgroup_storage_type {
 /* The argument is a structure. */
 #define BTF_FMODEL_STRUCT_ARG		BIT(0)
 
+/* The argument is signed. */
+#define BTF_FMODEL_SIGNED_ARG		BIT(1)
+
 struct btf_func_model {
 	u8 ret_size;
+	u8 ret_flags;
 	u8 nr_args;
 	u8 arg_size[MAX_BPF_FUNC_ARGS];
 	u8 arg_flags[MAX_BPF_FUNC_ARGS];
@@ -939,7 +943,13 @@ struct btf_func_model {
 /* Each call __bpf_prog_enter + call bpf_func + call __bpf_prog_exit is ~50
  * bytes on x86.
  */
-#define BPF_MAX_TRAMP_LINKS 38
+enum {
+#if defined(__s390x__)
+	BPF_MAX_TRAMP_LINKS = 27,
+#else
+	BPF_MAX_TRAMP_LINKS = 38,
+#endif
+};
 
 struct bpf_tramp_links {
 	struct bpf_tramp_link *links[BPF_MAX_TRAMP_LINKS];
@@ -1836,7 +1846,7 @@ struct bpf_prog * __must_check bpf_prog_inc_not_zero(struct bpf_prog *prog);
 void bpf_prog_put(struct bpf_prog *prog);
 
 void bpf_prog_free_id(struct bpf_prog *prog);
-void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock);
+void bpf_map_free_id(struct bpf_map *map);
 
 struct btf_field *btf_record_find(const struct btf_record *rec,
 				  u32 offset, enum btf_field_type type);
diff --git a/include/linux/btf.h b/include/linux/btf.h
index 5f628f323442..49e0fe6d8274 100644
--- a/include/linux/btf.h
+++ b/include/linux/btf.h
@@ -73,6 +73,14 @@
 #define KF_RCU          (1 << 7) /* kfunc only takes rcu pointer arguments */
 
 /*
+ * Tag marking a kernel function as a kfunc. This is meant to minimize the
+ * amount of copy-paste that kfunc authors have to include for correctness so
+ * as to avoid issues such as the compiler inlining or eliding either a static
+ * kfunc, or a global kfunc in an LTO build.
+ */
+#define __bpf_kfunc __used noinline
+
+/*
  * Return the name of the passed struct, if exists, or halt the build if for
  * example the structure gets renamed. In this way, developers have to revisit
  * the code using that structure name, and update it accordingly.
@@ -236,6 +244,16 @@ static inline bool btf_type_is_small_int(const struct btf_type *t)
 	return btf_type_is_int(t) && t->size <= sizeof(u64);
 }
 
+static inline u8 btf_int_encoding(const struct btf_type *t)
+{
+	return BTF_INT_ENCODING(*(u32 *)(t + 1));
+}
+
+static inline bool btf_type_is_signed_int(const struct btf_type *t)
+{
+	return btf_type_is_int(t) && (btf_int_encoding(t) & BTF_INT_SIGNED);
+}
+
 static inline bool btf_type_is_enum(const struct btf_type *t)
 {
 	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
@@ -306,11 +324,6 @@ static inline u8 btf_int_offset(const struct btf_type *t)
 	return BTF_INT_OFFSET(*(u32 *)(t + 1));
 }
 
-static inline u8 btf_int_encoding(const struct btf_type *t)
-{
-	return BTF_INT_ENCODING(*(u32 *)(t + 1));
-}
-
 static inline bool btf_type_is_scalar(const struct btf_type *t)
 {
 	return btf_type_is_int(t) || btf_type_is_enum(t);
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 38ab96ae0d68..d9cdbc047b49 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -47,6 +47,7 @@
 #include <uapi/linux/netdevice.h>
 #include <uapi/linux/if_bonding.h>
 #include <uapi/linux/pkt_cls.h>
+#include <uapi/linux/netdev.h>
 #include <linux/hashtable.h>
 #include <linux/rbtree.h>
 #include <net/net_trackers.h>
@@ -1819,6 +1820,7 @@ enum netdev_ml_priv_type {
  *			of Layer 2 headers.
  *
  *	@flags:		Interface flags (a la BSD)
+ *	@xdp_features:	XDP capability supported by the device
  *	@priv_flags:	Like 'flags' but invisible to userspace,
  *			see if.h for the definitions
  *	@gflags:	Global flags ( kept as legacy )
@@ -2060,6 +2062,7 @@ struct net_device {
 
 	/* Read-mostly cache-line for fast-path access */
 	unsigned int		flags;
+	xdp_features_t		xdp_features;
 	unsigned long long	priv_flags;
 	const struct net_device_ops *netdev_ops;
 	const struct xdp_metadata_ops *xdp_metadata_ops;
@@ -2846,6 +2849,7 @@ enum netdev_cmd {
 	NETDEV_OFFLOAD_XSTATS_DISABLE,
 	NETDEV_OFFLOAD_XSTATS_REPORT_USED,
 	NETDEV_OFFLOAD_XSTATS_REPORT_DELTA,
+	NETDEV_XDP_FEAT_CHANGE,
 };
 const char *netdev_cmd_to_name(enum netdev_cmd cmd);
 
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 91292aa13bc0..d517bfac937b 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -7,6 +7,7 @@
 #define __LINUX_NET_XDP_H__
 
 #include <linux/skbuff.h> /* skb_shared_info */
+#include <uapi/linux/netdev.h>
 
 /**
  * DOC: XDP RX-queue information
@@ -43,6 +44,8 @@ enum xdp_mem_type {
 	MEM_TYPE_MAX,
 };
 
+typedef u32 xdp_features_t;
+
 /* XDP flags for ndo_xdp_xmit */
 #define XDP_XMIT_FLUSH		(1U << 0)	/* doorbell signal consumer */
 #define XDP_XMIT_FLAGS_MASK	XDP_XMIT_FLUSH
@@ -425,9 +428,21 @@ MAX_XDP_METADATA_KFUNC,
 #ifdef CONFIG_NET
 u32 bpf_xdp_metadata_kfunc_id(int id);
 bool bpf_dev_bound_kfunc_id(u32 btf_id);
+void xdp_features_set_redirect_target(struct net_device *dev, bool support_sg);
+void xdp_features_clear_redirect_target(struct net_device *dev);
 #else
 static inline u32 bpf_xdp_metadata_kfunc_id(int id) { return 0; }
 static inline bool bpf_dev_bound_kfunc_id(u32 btf_id) { return false; }
+
+static inline void
+xdp_features_set_redirect_target(struct net_device *dev, bool support_sg)
+{
+}
+
+static inline void
+xdp_features_clear_redirect_target(struct net_device *dev)
+{
+}
 #endif
 
 #endif /* __LINUX_NET_XDP_H__ */
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index ba0f0cfb5e42..17afd2b35ee5 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -2801,7 +2801,7 @@ union bpf_attr {
  *
  * long bpf_perf_prog_read_value(struct bpf_perf_event_data *ctx, struct bpf_perf_event_value *buf, u32 buf_size)
  * 	Description
- * 		For en eBPF program attached to a perf event, retrieve the
+ * 		For an eBPF program attached to a perf event, retrieve the
  * 		value of the event counter associated to *ctx* and store it in
  * 		the structure pointed by *buf* and of size *buf_size*. Enabled
  * 		and running times are also stored in the structure (see
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
new file mode 100644
index 000000000000..9ee459872600
--- /dev/null
+++ b/include/uapi/linux/netdev.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/netdev.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_NETDEV_H
+#define _UAPI_LINUX_NETDEV_H
+
+#define NETDEV_FAMILY_NAME	"netdev"
+#define NETDEV_FAMILY_VERSION	1
+
+/**
+ * enum netdev_xdp_act
+ * @NETDEV_XDP_ACT_BASIC: XDP feautues set supported by all drivers
+ *   (XDP_ABORTED, XDP_DROP, XDP_PASS, XDP_TX)
+ * @NETDEV_XDP_ACT_REDIRECT: The netdev supports XDP_REDIRECT
+ * @NETDEV_XDP_ACT_NDO_XMIT: This feature informs if netdev implements
+ *   ndo_xdp_xmit callback.
+ * @NETDEV_XDP_ACT_XSK_ZEROCOPY: This feature informs if netdev supports AF_XDP
+ *   in zero copy mode.
+ * @NETDEV_XDP_ACT_HW_OFFLOAD: This feature informs if netdev supports XDP hw
+ *   oflloading.
+ * @NETDEV_XDP_ACT_RX_SG: This feature informs if netdev implements non-linear
+ *   XDP buffer support in the driver napi callback.
+ * @NETDEV_XDP_ACT_NDO_XMIT_SG: This feature informs if netdev implements
+ *   non-linear XDP buffer support in ndo_xdp_xmit callback.
+ */
+enum netdev_xdp_act {
+	NETDEV_XDP_ACT_BASIC = 1,
+	NETDEV_XDP_ACT_REDIRECT = 2,
+	NETDEV_XDP_ACT_NDO_XMIT = 4,
+	NETDEV_XDP_ACT_XSK_ZEROCOPY = 8,
+	NETDEV_XDP_ACT_HW_OFFLOAD = 16,
+	NETDEV_XDP_ACT_RX_SG = 32,
+	NETDEV_XDP_ACT_NDO_XMIT_SG = 64,
+};
+
+enum {
+	NETDEV_A_DEV_IFINDEX = 1,
+	NETDEV_A_DEV_PAD,
+	NETDEV_A_DEV_XDP_FEATURES,
+
+	__NETDEV_A_DEV_MAX,
+	NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1)
+};
+
+enum {
+	NETDEV_CMD_DEV_GET = 1,
+	NETDEV_CMD_DEV_ADD_NTF,
+	NETDEV_CMD_DEV_DEL_NTF,
+	NETDEV_CMD_DEV_CHANGE_NTF,
+
+	__NETDEV_CMD_MAX,
+	NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
+};
+
+#define NETDEV_MCGRP_MGMT	"mgmt"
+
+#endif /* _UAPI_LINUX_NETDEV_H */