commit f57c260f8415e635172f61e8bbd2c96fe3f96756
parent 81bed30d4af0eaf9bc882048dd6084a091912c1f
Author: Serban Stanca <sstanca@mozilla.com>
Date: Wed, 12 Nov 2025 15:35:31 +0200
Revert "Bug 1909910 - enable QUIC PMTUD r=necko-reviewers,kershaw" for causing xpcshell failures in test_http3_coalescing.js.
This reverts commit d673d2a47124bbf7f250cb86f6e1b5aafd76b6dd.
Diffstat:
3 files changed, 7 insertions(+), 28 deletions(-)
diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
@@ -15422,13 +15422,6 @@
value: 30
mirror: always
-# Whether to enable Packetization Layer Path MTU Discovery.
-- name: network.http.http3.pmtud
- type: RelaxedAtomicBool
- value: true
- mirror: always
- rust: true
-
# When true, a http request will be upgraded to https when HTTPS RR is
# available.
- name: network.dns.upgrade_with_https_rr
diff --git a/netwerk/socket/neqo_glue/src/lib.rs b/netwerk/socket/neqo_glue/src/lib.rs
@@ -423,8 +423,6 @@ impl NeqoHttp3Conn {
let pmtud_enabled =
// Check if PMTUD is explicitly enabled,
pmtud_enabled
- // or enabled via pref,
- || static_prefs::pref!("network.http.http3.pmtud")
// but disable PMTUD if NSPR is used (socket == None) or
// transmitted UDP datagrams might get fragmented by the IP layer.
&& socket.as_ref().map_or(false, |s| !s.may_fragment());
diff --git a/testing/web-platform/tests/webtransport/datagrams.https.any.js b/testing/web-platform/tests/webtransport/datagrams.https.any.js
@@ -199,25 +199,13 @@ promise_test(async t => {
const writer = wt.datagrams.writable.getWriter();
const reader = wt.datagrams.readable.getReader();
- let maxDatagramSize = wt.datagrams.maxDatagramSize;
-
- while (true) {
- // Write and read max-size datagram.
- await writer.write(new Uint8Array(maxDatagramSize + 1));
- // This should resolve with no datagram sent, which is hard to test for.
- // Wait for incoming datagrams to arrive, and if they do, fail.
- const result = await Promise.race([reader.read(), wait(500)]);
- if (result === undefined) {
- return; // Success, no datagram received, exit the test early.
- }
-
- // Maybe QUIC's PMTUD increased the max-size datagram in the meantime. If
- // so, try again.
- const currentMaxDatagramSize = wt.datagrams.maxDatagramSize;
- assert_greater_than(currentMaxDatagramSize, maxDatagramSize);
- maxDatagramSize = currentMaxDatagramSize;
- }
-}, 'Fail to transfer max-size+1 datagram, handle PMTUD increases');
+ // Write and read max-size datagram.
+ await writer.write(new Uint8Array(wt.datagrams.maxDatagramSize+1));
+ // This should resolve with no datagram sent, which is hard to test for.
+ // Wait for incoming datagrams to arrive, and if they do, fail.
+ const result = await Promise.race([reader.read(), wait(500)]);
+ assert_equals(result, undefined);
+}, 'Fail to transfer max-size+1 datagram');
promise_test(async t => {
// Make a WebTransport connection, but session is not necessarily established.
