<p>dexter has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.osmocom.org/c/osmo-bsc/+/22455">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">abis_rsl: check if emergency calling is disabled before premption<br><br>If an emergency call arrives at the BSC while all TCH are busy, one TCH<br>is cleared in favor of the emergency call. However, if emergency calls<br>are disabled (system information), it is still possible that an MS might<br>try an emergency call anyway or that due to interference a regular call<br>might look like an emergency call (channel request reason). In those<br>cases the preemption must not happen and the emergency call must be<br>rejected.<br><br>Change-Id: I1af1f4fefcbe6a886bb5396901ce0cb2368a0e19<br>Related: OS#4976<br>---<br>M src/osmo-bsc/abis_rsl.c<br>1 file changed, 12 insertions(+), 10 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.osmocom.org:29418/osmo-bsc refs/changes/55/22455/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/src/osmo-bsc/abis_rsl.c b/src/osmo-bsc/abis_rsl.c</span><br><span>index 321bcb4..9f25483 100644</span><br><span>--- a/src/osmo-bsc/abis_rsl.c</span><br><span>+++ b/src/osmo-bsc/abis_rsl.c</span><br><span>@@ -1684,6 +1684,18 @@</span><br><span> return;</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+ /* Block emergency calls if we explicitly disable them via sysinfo. */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rqd->reason == GSM_CHREQ_REASON_EMERG) {</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bts->si_common.rach_control.t2 & 0x4) {</span><br><span style="color: hsl(120, 100%, 40%);">+ LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD: MS attempts EMERGENCY CALL although EMERGENCY CALLS "</span><br><span style="color: hsl(120, 100%, 40%);">+ "are not allowed in sysinfo (spec violation by MS!)\n");</span><br><span style="color: hsl(120, 100%, 40%);">+ rsl_tx_imm_ass_rej(bts, &rqd->ref);</span><br><span style="color: hsl(120, 100%, 40%);">+ llist_del(&rqd->entry);</span><br><span style="color: hsl(120, 100%, 40%);">+ talloc_free(rqd);</span><br><span style="color: hsl(120, 100%, 40%);">+ return;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> /* Ensure that emergency calls will get priority over regular calls, however releasing</span><br><span> * lchan in favor of an emergency call may take some time, so we exit here. The lchan_fsm</span><br><span> * will poll again when an lchan becomes available. */</span><br><span>@@ -1702,16 +1714,6 @@</span><br><span> * - If there is still no channel available, try a TCH/F.</span><br><span> *</span><br><span> */</span><br><span style="color: hsl(0, 100%, 40%);">- if (rqd->reason == GSM_CHREQ_REASON_EMERG) {</span><br><span style="color: hsl(0, 100%, 40%);">- if (bts->si_common.rach_control.t2 & 0x4) {</span><br><span style="color: hsl(0, 100%, 40%);">- LOG_BTS(bts, DRSL, LOGL_NOTICE, "CHAN RQD: MS attempts EMERGENCY CALL although EMERGENCY CALLS "</span><br><span style="color: hsl(0, 100%, 40%);">- "are not allowed in sysinfo (spec violation by MS!)\n");</span><br><span style="color: hsl(0, 100%, 40%);">- rsl_tx_imm_ass_rej(bts, &rqd->ref);</span><br><span style="color: hsl(0, 100%, 40%);">- llist_del(&rqd->entry);</span><br><span style="color: hsl(0, 100%, 40%);">- talloc_free(rqd);</span><br><span style="color: hsl(0, 100%, 40%);">- return;</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span style="color: hsl(0, 100%, 40%);">- }</span><br><span> </span><br><span> /* Emergency calls will be put on a free TCH/H or TCH/F directly in the code below, all other channel requests</span><br><span> * will get an SDCCH first (if possible). */</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-bsc/+/22455">change 22455</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.osmocom.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.osmocom.org/c/osmo-bsc/+/22455"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: osmo-bsc </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: I1af1f4fefcbe6a886bb5396901ce0cb2368a0e19 </div>
<div style="display:none"> Gerrit-Change-Number: 22455 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: dexter <pmaier@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>