diff options
| author | Tiezhu Yang <yangtiezhu@loongson.cn> | 2022-05-10 11:35:03 +0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-05-10 10:13:06 -0700 |
| commit | 174efa7811659b3e3dec05b3649dc6d66c8c4628 (patch) | |
| tree | 24892851a0acbff68a88e3f3907b09ad198871ef /net/core | |
| parent | f922c8972fb53ad9221501e2e432f06246c74cc8 (diff) | |
bpf: Print some info if disable bpf_jit_enable failed
A user told me that bpf_jit_enable can be disabled on one system, but he
failed to disable bpf_jit_enable on the other system:
# echo 0 > /proc/sys/net/core/bpf_jit_enable
bash: echo: write error: Invalid argument
No useful info is available through the dmesg log, a quick analysis shows
that the issue is related with CONFIG_BPF_JIT_ALWAYS_ON.
When CONFIG_BPF_JIT_ALWAYS_ON is enabled, bpf_jit_enable is permanently set
to 1 and setting any other value than that will return failure.
It is better to print some info to tell the user if disable bpf_jit_enable
failed.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1652153703-22729-3-git-send-email-yangtiezhu@loongson.cn
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/sysctl_net_core.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c index cf00dd7d46d7..ca4527fcbc75 100644 --- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -266,6 +266,8 @@ static int proc_dointvec_minmax_bpf_enable(struct ctl_table *table, int write, loff_t *ppos) { int ret, jit_enable = *(int *)table->data; + int min = *(int *)table->extra1; + int max = *(int *)table->extra2; struct ctl_table tmp = *table; if (write && !capable(CAP_SYS_ADMIN)) @@ -283,6 +285,10 @@ static int proc_dointvec_minmax_bpf_enable(struct ctl_table *table, int write, ret = -EPERM; } } + + if (write && ret && min == max) + pr_info_once("CONFIG_BPF_JIT_ALWAYS_ON is enabled, bpf_jit_enable is permanently set to 1.\n"); + return ret; } |