From 1f4c51de3361f3d9223f7662b9567844e9fb7ca8 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 11 Feb 2020 14:53:56 -0600 Subject: lib: objagg: Replace zero-length arrays with flexible-array member The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertenly introduced[3] to the codebase from now on. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Acked-by: Jiri Pirko Signed-off-by: David S. Miller --- lib/objagg.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/objagg.c b/lib/objagg.c index 55621fb82e0a..5e1676ccdadd 100644 --- a/lib/objagg.c +++ b/lib/objagg.c @@ -28,7 +28,7 @@ struct objagg_hints_node { struct objagg_hints_node *parent; unsigned int root_id; struct objagg_obj_stats_info stats_info; - unsigned long obj[0]; + unsigned long obj[]; }; static struct objagg_hints_node * @@ -66,7 +66,7 @@ struct objagg_obj { * including nested objects */ struct objagg_obj_stats stats; - unsigned long obj[0]; + unsigned long obj[]; }; static unsigned int objagg_obj_ref_inc(struct objagg_obj *objagg_obj) -- cgit v1.2.3 From 6eac7795e8ef75de062c8f5bdb9520c9f0f065fa Mon Sep 17 00:00:00 2001 From: David Miller Date: Mon, 24 Feb 2020 15:01:44 +0100 Subject: bpf/tests: Use migrate disable instead of preempt disable 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. [ tglx: Switched it over to migrate disable ] Signed-off-by: David S. Miller Signed-off-by: Thomas Gleixner Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200224145643.785306549@linutronix.de --- lib/test_bpf.c | 4 ++-- net/bpf/test_run.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) (limited to 'lib') diff --git a/lib/test_bpf.c b/lib/test_bpf.c index cecb230833be..a5fddf9ebcb7 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -6660,14 +6660,14 @@ static int __run_one(const struct bpf_prog *fp, const void *data, u64 start, finish; int ret = 0, i; - preempt_disable(); + migrate_disable(); start = ktime_get_ns(); for (i = 0; i < runs; i++) ret = BPF_PROG_RUN(fp, data); finish = ktime_get_ns(); - preempt_enable(); + migrate_enable(); *duration = finish - start; do_div(*duration, runs); diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index d555c0d8657d..562443f94133 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -37,7 +37,7 @@ static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, repeat = 1; rcu_read_lock(); - preempt_disable(); + migrate_disable(); time_start = ktime_get_ns(); for (i = 0; i < repeat; i++) { bpf_cgroup_storage_set(storage); @@ -54,18 +54,18 @@ static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat, if (need_resched()) { time_spent += ktime_get_ns() - time_start; - preempt_enable(); + migrate_enable(); rcu_read_unlock(); cond_resched(); rcu_read_lock(); - preempt_disable(); + migrate_disable(); time_start = ktime_get_ns(); } } time_spent += ktime_get_ns() - time_start; - preempt_enable(); + migrate_enable(); rcu_read_unlock(); do_div(time_spent, repeat); -- cgit v1.2.3