From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (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 0744126CE39; Wed, 25 Mar 2026 13:22:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774444924; cv=none; b=C0jBLtYkP57VEk9HPdLjKv7L33WBW9nNaWqQtW2OZm2oVKO10gmcdQEheyvqn4uIGHhXTe35o4rgO75CxhcI3L2/WyQ904ghar5UhP92oQsi3DipNClzBc7cggZhsOMByzpl5v2g5oJEVrYNMmvK7EsjE3vm2M6IRNXcDTm/Wis= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774444924; c=relaxed/simple; bh=HqTxj7sOEZALR2O8Su9EVAnQRSJaZUEJV8z1DX7d6tU=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=GB7Gr1fetjgODhwUV0wzg2cWtwaXnPvxHgXoRrqyCkwFzXWWn/fGiQlbA2ebINcWahRVEG6UkZsr9KESx1H7bxfLX9Xp3/wsGsWZS3LYArXrJeuNuQGi+6ZluyzEZYAZKQVRwiuqIHzLRs1nqbiKqZzXfo8uGoMcXpYO/i21T7E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=gsFNHXSp; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="gsFNHXSp" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1774444921; bh=HqTxj7sOEZALR2O8Su9EVAnQRSJaZUEJV8z1DX7d6tU=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=gsFNHXSpZl/Q0vywoaL86ffWAwLADKAUOSCpoPze6z3shPbY8VToqRHU7PoxShcTA R/GXBYkxTohDuYVVqlXzeYnOsxY+tdbBVl1kIUvM0Oz8bLiK/agTXlXtrPuFUhT8I5 VC+b1HC7ChWzeq1VMKxMIl65OteRS5QJ9dOoHAbVeRADfntQLEwdhC+2y8Ah2cJIni xrgfNkARfBzCZ1ksKVfROCy9Mw9ZhQNweZI0UoaCpJIH36UU6dKgMLJF95eeaDG0UG Bfel6zgkxJ80PImM/uoZTOvDHBFThXv4YjEAnfr80g6wpqz87NTlibrCQCzar0mAfT 8toa4C5pq+xLQ== Received: from [IPv6:2606:6d00:15:e06b::c41] (unknown [IPv6:2606:6d00:15:e06b::c41]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: nicolas) by bali.collaboradmins.com (Postfix) with ESMTPSA id 3FA3417E5A46; Wed, 25 Mar 2026 14:22:00 +0100 (CET) Message-ID: Subject: Re: [PATCH] media: verisilicon: Remove unnecessary memset() after dma_alloc_coherent From: Nicolas Dufresne To: Luo Qiu , Benjamin Gaignard , Philipp Zabel , Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Date: Wed, 25 Mar 2026 09:21:57 -0400 In-Reply-To: <856D681C2A51EC65+20260325050055.1187863-1-luoqiu@kylinsec.com.cn> References: <856D681C2A51EC65+20260325050055.1187863-1-luoqiu@kylinsec.com.cn> Autocrypt: addr=nicolas.dufresne@collabora.com; prefer-encrypt=mutual; keydata=mDMEaCN2ixYJKwYBBAHaRw8BAQdAM0EHepTful3JOIzcPv6ekHOenE1u0vDG1gdHFrChD /e0J05pY29sYXMgRHVmcmVzbmUgPG5pY29sYXNAbmR1ZnJlc25lLmNhPoicBBMWCgBEAhsDBQsJCA cCAiICBhUKCQgLAgQWAgMBAh4HAheABQkJZfd1FiEE7w1SgRXEw8IaBG8S2UGUUSlgcvQFAmibrjo CGQEACgkQ2UGUUSlgcvQlQwD/RjpU1SZYcKG6pnfnQ8ivgtTkGDRUJ8gP3fK7+XUjRNIA/iXfhXMN abIWxO2oCXKf3TdD7aQ4070KO6zSxIcxgNQFtDFOaWNvbGFzIER1ZnJlc25lIDxuaWNvbGFzLmR1Z nJlc25lQGNvbGxhYm9yYS5jb20+iJkEExYKAEECGwMFCwkIBwICIgIGFQoJCAsCBBYCAwECHgcCF4 AWIQTvDVKBFcTDwhoEbxLZQZRRKWBy9AUCaCyyxgUJCWX3dQAKCRDZQZRRKWBy9ARJAP96pFmLffZ smBUpkyVBfFAf+zq6BJt769R0al3kHvUKdgD9G7KAHuioxD2v6SX7idpIazjzx8b8rfzwTWyOQWHC AAS0LU5pY29sYXMgRHVmcmVzbmUgPG5pY29sYXMuZHVmcmVzbmVAZ21haWwuY29tPoiZBBMWCgBBF iEE7w1SgRXEw8IaBG8S2UGUUSlgcvQFAmibrGYCGwMFCQll93UFCwkIBwICIgIGFQoJCAsCBBYCAw ECHgcCF4AACgkQ2UGUUSlgcvRObgD/YnQjfi4+L8f4fI7p1pPMTwRTcaRdy6aqkKEmKsCArzQBAK8 bRLv9QjuqsE6oQZra/RB4widZPvphs78H0P6NmpIJ Organization: Collabora Canada Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-k/642t1H1gbwycF4nsNk" User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 --=-k/642t1H1gbwycF4nsNk Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Le mercredi 25 mars 2026 =C3=A0 13:00 +0800, Luo Qiu a =C3=A9crit=C2=A0: > dma_alloc_coherent() already returns zeroed memory, so the subsequent > memset(0) calls are redundant. I don't think this statement is actually true, or at least not for all architectures, and not without an explicit GFP_ZERO flag. Nicolas >=20 > Signed-off-by: Luo Qiu > --- > =C2=A0drivers/media/platform/verisilicon/hantro_vp9.c | 3 --- > =C2=A01 file changed, 3 deletions(-) >=20 > diff --git a/drivers/media/platform/verisilicon/hantro_vp9.c b/drivers/me= dia/platform/verisilicon/hantro_vp9.c > index 566cd376c097..607d618e8f4a 100644 > --- a/drivers/media/platform/verisilicon/hantro_vp9.c > +++ b/drivers/media/platform/verisilicon/hantro_vp9.c > @@ -187,7 +187,6 @@ int hantro_vp9_dec_init(struct hantro_ctx *ctx) > =C2=A0 return -ENOMEM; > =C2=A0 > =C2=A0 tile_edge->size =3D size; > - memset(tile_edge->cpu, 0, size); > =C2=A0 > =C2=A0 size =3D hantro_vp9_segment_map_size(max_width, max_height); > =C2=A0 vp9_dec->segment_map_size =3D size; > @@ -198,7 +197,6 @@ int hantro_vp9_dec_init(struct hantro_ctx *ctx) > =C2=A0 goto err_segment_map; > =C2=A0 > =C2=A0 segment_map->size =3D size; > - memset(segment_map->cpu, 0, size); > =C2=A0 > =C2=A0 size =3D hantro_vp9_prob_tab_size(); > =C2=A0 vp9_dec->ctx_counters_offset =3D size; > @@ -211,7 +209,6 @@ int hantro_vp9_dec_init(struct hantro_ctx *ctx) > =C2=A0 goto err_misc; > =C2=A0 > =C2=A0 misc->size =3D size; > - memset(misc->cpu, 0, size); > =C2=A0 > =C2=A0 init_v4l2_vp9_count_tbl(ctx); > =C2=A0 --=-k/642t1H1gbwycF4nsNk Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTvDVKBFcTDwhoEbxLZQZRRKWBy9AUCacPhdQAKCRDZQZRRKWBy 9N9UAQCpvI0nr3Xogq9gNsgNBd5xLG2EZEWGzahgs/ORXqFrZAD9ERe1zJxCX6Qh BWSW91bYzrr5/ixlGp43idTR3Y/sWQw= =niaU -----END PGP SIGNATURE----- --=-k/642t1H1gbwycF4nsNk--