From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 8678B46D7E; Thu, 21 Aug 2025 04:44:12 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 255A140292; Thu, 21 Aug 2025 04:44:12 +0200 (CEST) Received: from inbox.dpdk.org (inbox.dpdk.org [95.142.172.178]) by mails.dpdk.org (Postfix) with ESMTP id 24D004026C for ; Thu, 21 Aug 2025 04:44:11 +0200 (CEST) Received: by inbox.dpdk.org (Postfix, from userid 33) id 191A046D80; Thu, 21 Aug 2025 04:44:11 +0200 (CEST) From: bugzilla@dpdk.org To: dev@dpdk.org Subject: [DPDK/testpmd Bug 1777] --max-pkt-len below 1500 does not seem to to be enforced Date: Thu, 21 Aug 2025 02:44:11 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: DPDK X-Bugzilla-Component: testpmd X-Bugzilla-Version: 22.11 X-Bugzilla-Keywords: X-Bugzilla-Severity: minor X-Bugzilla-Who: canary.overflow@gmail.com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: Normal X-Bugzilla-Assigned-To: dev@dpdk.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: Content-Type: multipart/alternative; boundary=17557442500.A5fecf.1818085 Content-Transfer-Encoding: 7bit X-Bugzilla-URL: https://bugs.dpdk.org/ Auto-Submitted: auto-generated X-Auto-Response-Suppress: All MIME-Version: 1.0 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org --17557442500.A5fecf.1818085 Date: Thu, 21 Aug 2025 04:44:10 +0200 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.dpdk.org/ Auto-Submitted: auto-generated X-Auto-Response-Suppress: All https://bugs.dpdk.org/show_bug.cgi?id=3D1777 Bug ID: 1777 Summary: --max-pkt-len below 1500 does not seem to to be enforced Product: DPDK Version: 22.11 Hardware: x86 OS: Linux Status: UNCONFIRMED Severity: minor Priority: Normal Component: testpmd Assignee: dev@dpdk.org Reporter: canary.overflow@gmail.com Target Milestone: --- I observed that setting --max-pkt-len to a value lower than 1500 does not enforce this value even though "show port info X" showed that the MTU was s= et to the value passed in. (e.g. packets larger than 800 bytes (> 1000 bytes) were still observed even though --max-pkt-len=3D800 was set) I believe that there is a default value that --max-pkt-len falls back on if= the value is too low. If this is the case, this value should also be reflected = in the port info. --=20 You are receiving this mail because: You are the assignee for the bug.= --17557442500.A5fecf.1818085 Date: Thu, 21 Aug 2025 04:44:10 +0200 MIME-Version: 1.0 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.dpdk.org/ Auto-Submitted: auto-generated X-Auto-Response-Suppress: All

Bug ID	1777
Summary	--max-pkt-len below 1500 does not seem to to be enforced
Product	DPDK
Version	22.11
Hardware	x86
OS	Linux
Status	UNCONFIRMED
Severity	minor
Priority	Normal
Component	testpmd
Assignee	dev@dpdk.org
Reporter	canary.overflow@gmail.com
Target Milestone	---

I observed that setting --max-pkt-=
len to a value lower than 1500 does not
enforce this value even though "show port info X" showed that the=
 MTU was set
to the value passed in.

(e.g. packets larger than 800 bytes (> 1000 bytes) were still observed e=
ven
though --max-pkt-len=3D800 was set)

I believe that there is a default value that --max-pkt-len falls back on if=
 the
value is too low. If this is the case, this value should also be reflected =
in
the port info.

You are receiving this mail because:

You are the assignee for the bug.

=20=20=20=20=20=20=20=20=20=20

= --17557442500.A5fecf.1818085--