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 061B722ACE3; Mon, 9 Dec 2024 12:58:39 +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=1733749119; cv=none; b=uVR/AKjCCb7om7ShQhU3qjC7282o09KCD7XvEcYrBpaRvCHJ09WwpZCG6hA7QE9ErnO5Vh4d7sJI3Z9jGTnkilnjRwjvtMUZUHdHUACTqtVXPewDpbtaUeSF3/C307OI5b8hnn3mbCGx/3k1FixaUH0+9fJoKnAQE5OXOGGA7dQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733749119; c=relaxed/simple; bh=l6YxVhjjcPNXX3KSThtrFQnv9KW0AjVXF9OlJ6931KE=; h=Mime-Version:Content-Type:Date:Message-Id:Cc:Subject:From:To: References:In-Reply-To; b=TyhJHGuV7y6kKX6njCQND4HqEIfnGwxoQ2pDBwPv6dPt9mosxMeHmTRHaFleRDWQV+rZyFZe+85DzhSpaLit4vB6Tn4ClLjLsyIzn6AUJCdvVLraZdQIc5ANsLIl7yfp+aS0dUHnaNyWP0ZE1Kss/lYFet8Lj30f+pOZEsdAP2o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IztltQZe; 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="IztltQZe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 48A72C4CED1; Mon, 9 Dec 2024 12:58:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733749118; bh=l6YxVhjjcPNXX3KSThtrFQnv9KW0AjVXF9OlJ6931KE=; h=Date:Cc:Subject:From:To:References:In-Reply-To:From; b=IztltQZeEnfq3iGifVzcriBgdPEb0+E6XtU55bFpXDEhSP3M7o9rZrzcL9SRsLPx/ yxspvMGP9HJ+Sw449LZVeq782KIwxU1t7Ll1WkILEoCUPO92LU+ymmXNdEtiLOCjyr AGTOudAaNcWNIC5D2LbV1Af5f6A3e5PMoNzOUzjPgJJ1jOO2hpzA2EQ0FUUFJ0Yflv A00+fDQnz6EEer1inW3rFY4OeO0rhYoP40SrR/yprV9+AhanRVRJq+oBcn0mjS/jq0 7/1q4zPHI59e8VktfH4m/1gv5hAZ/YQJrOX9rF3dXdV89jRNj2gBGoX0uc7DmD1GSM cqKrM2te6hf/w== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Mon, 09 Dec 2024 14:58:33 +0200 Message-Id: Cc: "Peter Huewe" , "Jason Gunthorpe" , "James Bottomley" , , , Subject: Re: [REGRESSION][BISECTED] tpm: Popping noise in USB headphones since 1b6d7f9eb150 From: "Jarkko Sakkinen" To: "Stefan Berger" , "Christian Heusel" X-Mailer: aerc 0.18.2 References: <7d052744-4bfa-40bc-ba06-1b4c47a5eb87@heusel.eu> In-Reply-To: On Tue Dec 3, 2024 at 12:15 AM EET, Stefan Berger wrote: > > > On 11/29/24 9:44 PM, Jarkko Sakkinen wrote: > > On Tue Nov 26, 2024 at 1:42 PM EET, Christian Heusel wrote: > >> On 24/10/25 05:47PM, Jarkko Sakkinen wrote: > >>> Yeah, this is on the list. > >>> > >>> See: https://bugzilla.kernel.org/show_bug.cgi?id=3D219383#c5 > >>> > >>> I had a fix for the AMD boot-time issue already over a month ago > >>> but unfortunately took time to get enough feedback. > >>> > >>> BR, Jarkko > >> > >> I'm not sure if this is supposed to be fixed, but AFAIK we hoped that > >> the patchset that was mentioned in bugzilla also helped this issue. > >> > >> The reporter said that the bug is still present in 6.12.1, so this mig= ht > >> need further poking =F0=9F=A4=94 > >=20 > > I'd suggest a workaround for the time being. > >=20 > > In 6.12 we added this for (heavy) IMA use: > >=20 > > tpm.disable_pcr_integrity=3D [HW,TPM] > > Do not protect PCR registers from unintended p= hysical > > access, or interposers in the bus by the means= of > > having an integrity protected session wrapped = around > > TPM2_PCR_Extend command. Consider this in a si= tuation > > where TPM is heavily utilized by IMA, thus pro= tection > > causing a major performance hit, and the space= where > > machines are deployed is by other means guarde= d. > >=20 > > Similarly it might make sense to have "tpm.disable_random_integrity" > > that disables the feature introduced by the failing commit. > >=20 > > I am wondering what could be the not-so-obvious root cause for this?=20 > Could it be due to a (TPM or RNG-related) lock? I guess the audio=20 > popping could occur if an application cannot meet timing requirements=20 > when it runs into some sort of blocking lock... The problem is that we don't know yet but we do know that it previously worked. Or more importantly: that is the hypothesis. So it would be in all cases useful to create such patch for A/B testing at minimum. BR, Jarkko