From 3c58482a382bae89410439247152eb342e9872f7 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 24 Feb 2020 15:01:41 +0100 Subject: bpf: Provide bpf_prog_run_pin_on_cpu() helper BPF programs require to run on one CPU to completion as they use per CPU storage, but according to Alexei they don't need reentrancy protection as obviously BPF programs running in thread context can always be 'preempted' by hard and soft interrupts and instrumentation and the same program can run concurrently on a different CPU. The currently used mechanism to ensure CPUness is to wrap the invocation into a preempt_disable/enable() pair. Disabling preemption is also disabling migration for a task. preempt_disable/enable() is used because there is no explicit way to reliably disable only migration. Provide a separate macro to invoke a BPF program which can be used in migrateable task context. It wraps BPF_PROG_RUN() in a migrate_disable/enable() pair which maps on non RT enabled kernels to preempt_disable/enable(). On RT enabled kernels this merely disables migration. Both methods ensure that the invoked BPF program runs on one CPU to completion. Signed-off-by: Thomas Gleixner Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200224145643.474592620@linutronix.de --- include/linux/filter.h | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/filter.h b/include/linux/filter.h index f349e2c0884c..38f60188bb26 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -576,8 +576,30 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); } \ ret; }) -#define BPF_PROG_RUN(prog, ctx) __BPF_PROG_RUN(prog, ctx, \ - bpf_dispatcher_nopfunc) +#define BPF_PROG_RUN(prog, ctx) \ + __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nopfunc) + +/* + * Use in preemptible and therefore migratable context to make sure that + * the execution of the BPF program runs on one CPU. + * + * This uses migrate_disable/enable() explicitly to document that the + * invocation of a BPF program does not require reentrancy protection + * against a BPF program which is invoked from a preempting task. + * + * For non RT enabled kernels migrate_disable/enable() maps to + * preempt_disable/enable(), i.e. it disables also preemption. + */ +static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog, + const void *ctx) +{ + u32 ret; + + migrate_disable(); + ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nopfunc); + migrate_enable(); + return ret; +} #define BPF_SKB_CB_LEN QDISC_CB_PRIV_LEN -- cgit v1.3-14-g43fede From 37e1d9202225635772b32e340294208367279c2b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 24 Feb 2020 15:01:42 +0100 Subject: bpf: Replace cant_sleep() with cant_migrate() As already discussed in the previous change which introduced BPF_RUN_PROG_PIN_ON_CPU() BPF only requires to disable migration to guarantee per CPUness. If RT substitutes the preempt disable based migration protection then the cant_sleep() check will obviously trigger as preemption is not disabled. Replace it by cant_migrate() which maps to cant_sleep() on a non RT kernel and will verify that migration is disabled on a full RT kernel. Signed-off-by: Thomas Gleixner Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200224145643.583038889@linutronix.de --- include/linux/filter.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/filter.h b/include/linux/filter.h index 38f60188bb26..1982a52eb4c9 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -561,7 +561,7 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); #define __BPF_PROG_RUN(prog, ctx, dfunc) ({ \ u32 ret; \ - cant_sleep(); \ + cant_migrate(); \ if (static_branch_unlikely(&bpf_stats_enabled_key)) { \ struct bpf_prog_stats *stats; \ u64 start = sched_clock(); \ -- cgit v1.3-14-g43fede From 3d9f773cf2876c01a505b9fe27270901d464e90a Mon Sep 17 00:00:00 2001 From: David Miller Date: Mon, 24 Feb 2020 15:01:43 +0100 Subject: bpf: Use bpf_prog_run_pin_on_cpu() at simple call sites. All of these cases are strictly of the form: preempt_disable(); BPF_PROG_RUN(...); preempt_enable(); Replace this with bpf_prog_run_pin_on_cpu() which wraps BPF_PROG_RUN() with: migrate_disable(); BPF_PROG_RUN(...); migrate_enable(); On non RT enabled kernels this maps to preempt_disable/enable() and on RT enabled kernels this solely prevents migration, which is sufficient as there is no requirement to prevent reentrancy to any BPF program from a preempting task. The only requirement is that the program stays on the same CPU. Therefore, this is a trivially correct transformation. The seccomp loop does not need protection over the loop. It only needs protection per BPF filter program [ tglx: Converted to bpf_prog_run_pin_on_cpu() ] Signed-off-by: David S. Miller Signed-off-by: Thomas Gleixner Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200224145643.691493094@linutronix.de --- include/linux/filter.h | 4 +--- kernel/seccomp.c | 4 +--- net/core/flow_dissector.c | 4 +--- net/core/skmsg.c | 8 ++------ net/kcm/kcmsock.c | 4 +--- 5 files changed, 6 insertions(+), 18 deletions(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/filter.h b/include/linux/filter.h index 1982a52eb4c9..9270de2a0df8 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -717,9 +717,7 @@ static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, if (unlikely(prog->cb_access)) memset(cb_data, 0, BPF_SKB_CB_LEN); - preempt_disable(); - res = BPF_PROG_RUN(prog, skb); - preempt_enable(); + res = bpf_prog_run_pin_on_cpu(prog, skb); return res; } diff --git a/kernel/seccomp.c b/kernel/seccomp.c index b6ea3dcb57bf..787041eb011b 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -268,16 +268,14 @@ static u32 seccomp_run_filters(const struct seccomp_data *sd, * All filters in the list are evaluated and the lowest BPF return * value always takes priority (ignoring the DATA). */ - preempt_disable(); for (; f; f = f->prev) { - u32 cur_ret = BPF_PROG_RUN(f->prog, sd); + u32 cur_ret = bpf_prog_run_pin_on_cpu(f->prog, sd); if (ACTION_ONLY(cur_ret) < ACTION_ONLY(ret)) { ret = cur_ret; *match = f; } } - preempt_enable(); return ret; } #endif /* CONFIG_SECCOMP_FILTER */ diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index a1670dff0629..3eff84824c8b 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -920,9 +920,7 @@ bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx, (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP); flow_keys->flags = flags; - preempt_disable(); - result = BPF_PROG_RUN(prog, ctx); - preempt_enable(); + result = bpf_prog_run_pin_on_cpu(prog, ctx); flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen); flow_keys->thoff = clamp_t(u16, flow_keys->thoff, diff --git a/net/core/skmsg.c b/net/core/skmsg.c index eeb28cb85664..c479372f2cd2 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -628,7 +628,6 @@ int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock, struct bpf_prog *prog; int ret; - preempt_disable(); rcu_read_lock(); prog = READ_ONCE(psock->progs.msg_parser); if (unlikely(!prog)) { @@ -638,7 +637,7 @@ int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock, sk_msg_compute_data_pointers(msg); msg->sk = sk; - ret = BPF_PROG_RUN(prog, msg); + ret = bpf_prog_run_pin_on_cpu(prog, msg); ret = sk_psock_map_verd(ret, msg->sk_redir); psock->apply_bytes = msg->apply_bytes; if (ret == __SK_REDIRECT) { @@ -653,7 +652,6 @@ int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock, } out: rcu_read_unlock(); - preempt_enable(); return ret; } EXPORT_SYMBOL_GPL(sk_psock_msg_verdict); @@ -665,9 +663,7 @@ static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog, skb->sk = psock->sk; bpf_compute_data_end_sk_skb(skb); - preempt_disable(); - ret = BPF_PROG_RUN(prog, skb); - preempt_enable(); + ret = bpf_prog_run_pin_on_cpu(prog, skb); /* strparser clones the skb before handing it to a upper layer, * meaning skb_orphan has been called. We NULL sk on the way out * to ensure we don't trigger a BUG_ON() in skb/sk operations diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index ea9e73428ed9..56fac24a627a 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -380,9 +380,7 @@ static int kcm_parse_func_strparser(struct strparser *strp, struct sk_buff *skb) struct bpf_prog *prog = psock->bpf_prog; int res; - preempt_disable(); - res = BPF_PROG_RUN(prog, skb); - preempt_enable(); + res = bpf_prog_run_pin_on_cpu(prog, skb); return res; } -- cgit v1.3-14-g43fede From 2a916f2f546ca1c1e3323e2a4269307f6d9890eb Mon Sep 17 00:00:00 2001 From: David Miller Date: Mon, 24 Feb 2020 15:01:46 +0100 Subject: bpf: Use migrate_disable/enable in array macros and cgroup/lirc code. Replace the preemption disable/enable with migrate_disable/enable() to reflect the actual requirement and to allow PREEMPT_RT to substitute it with an actual migration disable mechanism which does not disable preemption. Including the code paths that go via __bpf_prog_run_save_cb(). Signed-off-by: David S. Miller Signed-off-by: Thomas Gleixner Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200224145643.998293311@linutronix.de --- include/linux/bpf.h | 8 ++++---- include/linux/filter.h | 5 +++-- 2 files changed, 7 insertions(+), 6 deletions(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 49b1a70e12c8..76b3a0eb1502 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -885,7 +885,7 @@ int bpf_prog_array_copy(struct bpf_prog_array *old_array, struct bpf_prog *_prog; \ struct bpf_prog_array *_array; \ u32 _ret = 1; \ - preempt_disable(); \ + migrate_disable(); \ rcu_read_lock(); \ _array = rcu_dereference(array); \ if (unlikely(check_non_null && !_array))\ @@ -898,7 +898,7 @@ int bpf_prog_array_copy(struct bpf_prog_array *old_array, } \ _out: \ rcu_read_unlock(); \ - preempt_enable(); \ + migrate_enable(); \ _ret; \ }) @@ -932,7 +932,7 @@ _out: \ u32 ret; \ u32 _ret = 1; \ u32 _cn = 0; \ - preempt_disable(); \ + migrate_disable(); \ rcu_read_lock(); \ _array = rcu_dereference(array); \ _item = &_array->items[0]; \ @@ -944,7 +944,7 @@ _out: \ _item++; \ } \ rcu_read_unlock(); \ - preempt_enable(); \ + migrate_enable(); \ if (_ret) \ _ret = (_cn ? NET_XMIT_CN : NET_XMIT_SUCCESS); \ else \ diff --git a/include/linux/filter.h b/include/linux/filter.h index 9270de2a0df8..43b5e455d2f5 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -677,6 +677,7 @@ static inline u8 *bpf_skb_cb(struct sk_buff *skb) return qdisc_skb_cb(skb)->data; } +/* Must be invoked with migration disabled */ static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog, struct sk_buff *skb) { @@ -702,9 +703,9 @@ static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog, { u32 res; - preempt_disable(); + migrate_disable(); res = __bpf_prog_run_save_cb(prog, skb); - preempt_enable(); + migrate_enable(); return res; } -- cgit v1.3-14-g43fede From 6a64037d4bf252bb8cf13917320c8e001da8997a Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 12 Mar 2020 20:55:57 +0100 Subject: bpf: Add bpf_trampoline_ name prefix for DECLARE_BPF_DISPATCHER MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Adding bpf_trampoline_ name prefix for DECLARE_BPF_DISPATCHER, so all the dispatchers have the common name prefix. And also a small '_' cleanup for bpf_dispatcher_nopfunc function name. Signed-off-by: Björn Töpel Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200312195610.346362-3-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 21 +++++++++++---------- include/linux/filter.h | 9 ++++----- net/core/filter.c | 5 ++--- 3 files changed, 17 insertions(+), 18 deletions(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c2f815e9f7d0..fe1f8b075378 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -522,7 +522,7 @@ struct bpf_dispatcher { u32 image_off; }; -static __always_inline unsigned int bpf_dispatcher_nopfunc( +static __always_inline unsigned int bpf_dispatcher_nop_func( const void *ctx, const struct bpf_insn *insnsi, unsigned int (*bpf_func)(const void *, @@ -537,7 +537,7 @@ int bpf_trampoline_unlink_prog(struct bpf_prog *prog); void bpf_trampoline_put(struct bpf_trampoline *tr); #define BPF_DISPATCHER_INIT(name) { \ .mutex = __MUTEX_INITIALIZER(name.mutex), \ - .func = &name##func, \ + .func = &name##_func, \ .progs = {}, \ .num_progs = 0, \ .image = NULL, \ @@ -545,7 +545,7 @@ void bpf_trampoline_put(struct bpf_trampoline *tr); } #define DEFINE_BPF_DISPATCHER(name) \ - noinline unsigned int name##func( \ + noinline unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ unsigned int (*bpf_func)(const void *, \ @@ -553,17 +553,18 @@ void bpf_trampoline_put(struct bpf_trampoline *tr); { \ return bpf_func(ctx, insnsi); \ } \ - EXPORT_SYMBOL(name##func); \ - struct bpf_dispatcher name = BPF_DISPATCHER_INIT(name); + EXPORT_SYMBOL(bpf_dispatcher_##name##_func); \ + struct bpf_dispatcher bpf_dispatcher_##name = \ + BPF_DISPATCHER_INIT(bpf_dispatcher_##name); #define DECLARE_BPF_DISPATCHER(name) \ - unsigned int name##func( \ + unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ unsigned int (*bpf_func)(const void *, \ const struct bpf_insn *)); \ - extern struct bpf_dispatcher name; -#define BPF_DISPATCHER_FUNC(name) name##func -#define BPF_DISPATCHER_PTR(name) (&name) + extern struct bpf_dispatcher bpf_dispatcher_##name; +#define BPF_DISPATCHER_FUNC(name) bpf_dispatcher_##name##_func +#define BPF_DISPATCHER_PTR(name) (&bpf_dispatcher_##name) void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from, struct bpf_prog *to); struct bpf_image { @@ -589,7 +590,7 @@ static inline int bpf_trampoline_unlink_prog(struct bpf_prog *prog) static inline void bpf_trampoline_put(struct bpf_trampoline *tr) {} #define DEFINE_BPF_DISPATCHER(name) #define DECLARE_BPF_DISPATCHER(name) -#define BPF_DISPATCHER_FUNC(name) bpf_dispatcher_nopfunc +#define BPF_DISPATCHER_FUNC(name) bpf_dispatcher_nop_func #define BPF_DISPATCHER_PTR(name) NULL static inline void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from, diff --git a/include/linux/filter.h b/include/linux/filter.h index 43b5e455d2f5..6249679275b3 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -577,7 +577,7 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key); ret; }) #define BPF_PROG_RUN(prog, ctx) \ - __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nopfunc) + __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func) /* * Use in preemptible and therefore migratable context to make sure that @@ -596,7 +596,7 @@ static inline u32 bpf_prog_run_pin_on_cpu(const struct bpf_prog *prog, u32 ret; migrate_disable(); - ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nopfunc); + ret = __BPF_PROG_RUN(prog, ctx, bpf_dispatcher_nop_func); migrate_enable(); return ret; } @@ -722,7 +722,7 @@ static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, return res; } -DECLARE_BPF_DISPATCHER(bpf_dispatcher_xdp) +DECLARE_BPF_DISPATCHER(xdp) static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, struct xdp_buff *xdp) @@ -733,8 +733,7 @@ static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, * already takes rcu_read_lock() when fetching the program, so * it's not necessary here anymore. */ - return __BPF_PROG_RUN(prog, xdp, - BPF_DISPATCHER_FUNC(bpf_dispatcher_xdp)); + return __BPF_PROG_RUN(prog, xdp, BPF_DISPATCHER_FUNC(xdp)); } void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); diff --git a/net/core/filter.c b/net/core/filter.c index 22219544410f..96350a743539 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -8859,10 +8859,9 @@ const struct bpf_prog_ops sk_reuseport_prog_ops = { }; #endif /* CONFIG_INET */ -DEFINE_BPF_DISPATCHER(bpf_dispatcher_xdp) +DEFINE_BPF_DISPATCHER(xdp) void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog) { - bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(bpf_dispatcher_xdp), - prev_prog, prog); + bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog); } -- cgit v1.3-14-g43fede From bfea9a8574f34597581f74f792d044d38497b775 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Thu, 12 Mar 2020 20:55:59 +0100 Subject: bpf: Add name to struct bpf_ksym Adding name to 'struct bpf_ksym' object to carry the name of the symbol for bpf_prog, bpf_trampoline, bpf_dispatcher objects. The current benefit is that name is now generated only when the symbol is added to the list, so we don't need to generate it every time it's accessed. The future benefit is that we will have all the bpf objects symbols represented by struct bpf_ksym. Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20200312195610.346362-5-jolsa@kernel.org Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 2 ++ include/linux/filter.h | 6 ------ kernel/bpf/core.c | 9 ++++++--- kernel/events/core.c | 9 ++++----- 4 files changed, 12 insertions(+), 14 deletions(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 6ca3d5c8ccf3..047b44deb3c5 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -18,6 +18,7 @@ #include #include #include +#include struct bpf_verifier_env; struct bpf_verifier_log; @@ -474,6 +475,7 @@ void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start); struct bpf_ksym { unsigned long start; unsigned long end; + char name[KSYM_NAME_LEN]; }; enum bpf_tramp_prog_type { diff --git a/include/linux/filter.h b/include/linux/filter.h index 6249679275b3..9b5aa5c483cc 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1083,7 +1083,6 @@ bpf_address_lookup(unsigned long addr, unsigned long *size, void bpf_prog_kallsyms_add(struct bpf_prog *fp); void bpf_prog_kallsyms_del(struct bpf_prog *fp); -void bpf_get_prog_name(const struct bpf_prog *prog, char *sym); #else /* CONFIG_BPF_JIT */ @@ -1152,11 +1151,6 @@ static inline void bpf_prog_kallsyms_del(struct bpf_prog *fp) { } -static inline void bpf_get_prog_name(const struct bpf_prog *prog, char *sym) -{ - sym[0] = '\0'; -} - #endif /* CONFIG_BPF_JIT */ void bpf_prog_kallsyms_del_all(struct bpf_prog *fp); diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index e587d6306d7c..f6800c2d4b01 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -535,8 +535,10 @@ bpf_prog_ksym_set_addr(struct bpf_prog *prog) prog->aux->ksym.end = addr + hdr->pages * PAGE_SIZE; } -void bpf_get_prog_name(const struct bpf_prog *prog, char *sym) +static void +bpf_prog_ksym_set_name(struct bpf_prog *prog) { + char *sym = prog->aux->ksym.name; const char *end = sym + KSYM_NAME_LEN; const struct btf_type *type; const char *func_name; @@ -643,6 +645,7 @@ void bpf_prog_kallsyms_add(struct bpf_prog *fp) return; bpf_prog_ksym_set_addr(fp); + bpf_prog_ksym_set_name(fp); spin_lock_bh(&bpf_lock); bpf_prog_ksym_node_add(fp->aux); @@ -681,7 +684,7 @@ const char *__bpf_address_lookup(unsigned long addr, unsigned long *size, unsigned long symbol_start = prog->aux->ksym.start; unsigned long symbol_end = prog->aux->ksym.end; - bpf_get_prog_name(prog, sym); + strncpy(sym, prog->aux->ksym.name, KSYM_NAME_LEN); ret = sym; if (size) @@ -738,7 +741,7 @@ int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type, if (it++ != symnum) continue; - bpf_get_prog_name(aux->prog, sym); + strncpy(sym, aux->ksym.name, KSYM_NAME_LEN); *value = (unsigned long)aux->prog->bpf_func; *type = BPF_SYM_ELF_TYPE; diff --git a/kernel/events/core.c b/kernel/events/core.c index bbdfac0182f4..9b89ef176247 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8255,23 +8255,22 @@ static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, enum perf_bpf_event_type type) { bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; - char sym[KSYM_NAME_LEN]; int i; if (prog->aux->func_cnt == 0) { - bpf_get_prog_name(prog, sym); perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, (u64)(unsigned long)prog->bpf_func, - prog->jited_len, unregister, sym); + prog->jited_len, unregister, + prog->aux->ksym.name); } else { for (i = 0; i < prog->aux->func_cnt; i++) { struct bpf_prog *subprog = prog->aux->func[i]; - bpf_get_prog_name(subprog, sym); perf_event_ksymbol( PERF_RECORD_KSYMBOL_TYPE_BPF, (u64)(unsigned long)subprog->bpf_func, - subprog->jited_len, unregister, sym); + subprog->jited_len, unregister, + prog->aux->ksym.name); } } } -- cgit v1.3-14-g43fede