From 38ff3e6bb987ec583268da8eb22628293095d43b Mon Sep 17 00:00:00 2001 From: Neil Horman <nhorman@tuxdriver.com> Date: Fri, 15 Jan 2010 01:40:55 -0800 Subject: [PATCH] dccp_probe: Fix module load dependencies between dccp and dccp_probe This was just recently reported to me. When built as modules, the dccp_probe module has a silent dependency on the dccp module. This stems from the fact that the module_init routine of dccp_probe registers a jprobe on the dccp_sendmsg symbol. Since the symbol is only referenced as a text string (the .symbol_name field in the jprobe struct) rather than the address of the symbol itself, depmod never picks this dependency up, and so if you load the dccp_probe module without the dccp module loaded, the register_jprobe call fails with an -EINVAL, and the whole module load fails. The fix is pretty easy, we can just wrap the register_jprobe call in a try_then_request_module call, which forces the dependency to get satisfied prior to the probe registration. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- net/dccp/probe.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/dccp/probe.c b/net/dccp/probe.c index dc328425fa20d..6fcfe87450438 100644 --- a/net/dccp/probe.c +++ b/net/dccp/probe.c @@ -163,7 +163,8 @@ static __init int dccpprobe_init(void) if (!proc_net_fops_create(&init_net, procname, S_IRUSR, &dccpprobe_fops)) goto err0; - ret = register_jprobe(&dccp_send_probe); + ret = try_then_request_module((register_jprobe(&dccp_send_probe) == 0), + "dccp"); if (ret) goto err1; -- GitLab