Commit 7d9b3ad4 authored by Andrii Nakryiko's avatar Andrii Nakryiko
Browse files

Merge branch 'Fixes for kfunc-mod regressions and warnings' 

Kumar Kartikeya says:

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

This set includes fixes for two regressions and one build warning introduced by
the kfunc for modules series.

Changelog:
----------

v1 -> v2:
v1: https://lore.kernel.org/bpf/20211115191840.496263-1-memxor@gmail.com



 * Instead of demoting resolve_btfids warning to debug, only skip in case of
   set->cnt == 0.
====================

Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
parents 099f83aa 3345193f

include/linux/btf.h

+10 −4
Original line number Diff line number Diff line
@@ -245,7 +245,10 @@ struct kfunc_btf_id_set { 
	struct module *owner;

};



struct kfunc_btf_id_list;

struct kfunc_btf_id_list {

	struct list_head list;

	struct mutex mutex;

};



#ifdef CONFIG_DEBUG_INFO_BTF_MODULES

void register_kfunc_btf_id_set(struct kfunc_btf_id_list *l,
@@ -254,6 +257,9 @@ void unregister_kfunc_btf_id_set(struct kfunc_btf_id_list *l, 
				 struct kfunc_btf_id_set *s);

bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, u32 kfunc_id,

			      struct module *owner);



extern struct kfunc_btf_id_list bpf_tcp_ca_kfunc_list;

extern struct kfunc_btf_id_list prog_test_kfunc_list;

#else

static inline void register_kfunc_btf_id_set(struct kfunc_btf_id_list *l,

					     struct kfunc_btf_id_set *s)
@@ -268,13 +274,13 @@ static inline bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, 
{

	return false;

}



static struct kfunc_btf_id_list bpf_tcp_ca_kfunc_list __maybe_unused;

static struct kfunc_btf_id_list prog_test_kfunc_list __maybe_unused;

#endif



#define DEFINE_KFUNC_BTF_ID_SET(set, name)                                     \

	struct kfunc_btf_id_set name = { LIST_HEAD_INIT(name.list), (set),     \

					 THIS_MODULE }



extern struct kfunc_btf_id_list bpf_tcp_ca_kfunc_list;

extern struct kfunc_btf_id_list prog_test_kfunc_list;



#endif

kernel/bpf/btf.c

+2 −9
Original line number Diff line number Diff line
@@ -6346,11 +6346,6 @@ BTF_ID_LIST_GLOBAL_SINGLE(btf_task_struct_ids, struct, task_struct) 


/* BTF ID set registration API for modules */



struct kfunc_btf_id_list {

	struct list_head list;

	struct mutex mutex;

};



#ifdef CONFIG_DEBUG_INFO_BTF_MODULES



void register_kfunc_btf_id_set(struct kfunc_btf_id_list *l,
@@ -6376,8 +6371,6 @@ bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, u32 kfunc_id, 
{

	struct kfunc_btf_id_set *s;



	if (!owner)

		return false;

	mutex_lock(&klist->mutex);

	list_for_each_entry(s, &klist->list, list) {

		if (s->owner == owner && btf_id_set_contains(s->set, kfunc_id)) {
@@ -6389,8 +6382,6 @@ bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, u32 kfunc_id, 
	return false;

}



#endif



#define DEFINE_KFUNC_BTF_ID_LIST(name)                                         \

	struct kfunc_btf_id_list name = { LIST_HEAD_INIT(name.list),           \

					  __MUTEX_INITIALIZER(name.mutex) };   \
@@ -6398,3 +6389,5 @@ bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, u32 kfunc_id, 


DEFINE_KFUNC_BTF_ID_LIST(bpf_tcp_ca_kfunc_list);

DEFINE_KFUNC_BTF_ID_LIST(prog_test_kfunc_list);



#endif

lib/Kconfig.debug

+1 −0
Original line number Diff line number Diff line
@@ -316,6 +316,7 @@ config DEBUG_INFO_BTF 
	bool "Generate BTF typeinfo"

	depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED

	depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST

	depends on BPF_SYSCALL

	help

	  Generate deduplicated BTF type information from DWARF debug info.

	  Turning this on expects presence of pahole tool, which will convert

tools/bpf/resolve_btfids/main.c

+5 −3
Original line number Diff line number Diff line
@@ -83,6 +83,7 @@ struct btf_id { 
		int	 cnt;

	};

	int		 addr_cnt;

	bool		 is_set;

	Elf64_Addr	 addr[ADDR_CNT];

};
@@ -451,8 +452,10 @@ static int symbols_collect(struct object *obj) 
			 * in symbol's size, together with 'cnt' field hence

			 * that - 1.

			 */

			if (id)

			if (id) {

				id->cnt = sym.st_size / sizeof(int) - 1;

				id->is_set = true;

			}

		} else {

			pr_err("FAILED unsupported prefix %s\n", prefix);

			return -1;
@@ -568,9 +571,8 @@ static int id_patch(struct object *obj, struct btf_id *id) 
	int *ptr = data->d_buf;

	int i;



	if (!id->id) {

	if (!id->id && !id->is_set)

		pr_err("WARN: resolve_btfids: unresolved symbol %s\n", id->name);

	}



	for (i = 0; i < id->addr_cnt; i++) {

		unsigned long addr = id->addr[i];