From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 105F0207A1A for ; Wed, 6 Nov 2024 18:57:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730919448; cv=none; b=GnMXzAw/Afa8JlJg0z85Jv9BOpT5VJTXrl0lEXJYdeoNSR4PUrIw1R/orPR2nMjksbKjzNruhUJl5EmJtG5ICWnx1G3Ifecec850yUgSYczIuUVplOMSNxUdiW8HfjjhcsG1eV5x1OAXCBWrnP38JVrDIhq2nIVMSqu0fzN1NFg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730919448; c=relaxed/simple; bh=iaztL4lgaGUJOJlSqhcJDyDAEevvmS1wjxAiJLl1feE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Jq1We1Du3pc+8KvbKyp2aa4ljRUp2qLmBYl0400zCTn0StyEjHQhfJaQuthhb9guYmQYr8jaOuRpJDsyNO5Wo3CrzFxghRLGMqycANfNcdeAPIvfjaLg+QusSF49zX6A0FzwtkTyG2MZKXE1D3E95xefHdru9KnGjs2DXI4mTuI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=l6mg0gNm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="l6mg0gNm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5FA44C4CEC6; Wed, 6 Nov 2024 18:57:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730919446; bh=iaztL4lgaGUJOJlSqhcJDyDAEevvmS1wjxAiJLl1feE=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=l6mg0gNm0iwKFxjL09lsAnrycoLjFHTcq5NyF6TtvTAhiJwMRhLSEIA9k96ejQ+TC 0MFBC1BEjQ2K41XHcGO7tT/HHRPhxEV7LjH+Ljz2LDVHU8+hQyFtU6xJWnV7Gss4XI kshSOeGMyuPBo/EFbeXQgS19fSSIL9ici17qSH8MZ2GWBlREwKOowCXlfyyVvbP2K2 lw6e2yeAlOUzlm3Ux3FSnC4TajinCTvWISLYGDCP80wtT7y6cMPpm8iiB9WLEiJCxk d5KFKAs7jLLTPttyEx/VFhzfHKmP8/CSYi2sFINAQXELNkZqf2rC1F9ZPtTst2NyI+ Iwq59erSm2eFQ== Message-ID: Date: Wed, 6 Nov 2024 11:57:25 -0700 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] net: ipv4: Cache pmtu for all packet paths if multipath enabled Content-Language: en-US To: Vladimir Vdovin , Ido Schimmel Cc: netdev@vger.kernel.org, davem@davemloft.net References: <20241029152206.303004-1-deliran@verdict.gg> <736cdd43-4c4b-4341-bd77-c9a365dec2e5@kernel.org> <59b0acc7-196c-4ab8-9033-336136a47212@kernel.org> From: David Ahern In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/6/24 10:20 AM, Vladimir Vdovin wrote: > On Tue Nov 5, 2024 at 6:52 AM MSK, David Ahern wrote: >> On 11/2/24 10:20 AM, Vladimir Vdovin wrote: >>>> >>>> Doesn't IPv6 suffer from a similar problem? >> >> I believe the answer is yes, but do not have time to find a reproducer >> right now. >> >>> >>> I am not very familiar with ipv6, >>> but I tried to reproduce same problem with my tests with same topology. >>> >>> ip netns exec ns_a-AHtoRb ip -6 r g fc00:1001::2:2 sport 30003 dport 443 >>> fc00:1001::2:2 via fc00:2::2 dev veth_A-R2 src fc00:1000::1:1 metric 1024 expires 495sec mtu 1500 pref medium >>> >>> ip netns exec ns_a-AHtoRb ip -6 r g fc00:1001::2:2 sport 30013 dport 443 >>> fc00:1001::2:2 via fc00:1::2 dev veth_A-R1 src fc00:1000::1:1 metric 1024 expires 484sec mtu 1500 pref medium you should dump the cache to see the full exception list. >>> >>> It seems that there are no problems with ipv6. We have nhce entries for both paths. >> >> Does rt6_cache_allowed_for_pmtu return true or false for this test? > It returns true. > > Looking at the code, it is creating a single exception - not one per path. I am fine with deferring the ipv6 patch until someone with time and interest can work on it.