From nobody Mon Feb 9 06:05:29 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (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 798F11DB54C for ; Wed, 17 Dec 2025 15:12:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765984350; cv=none; b=D8EkC/ICp+Fcy4+qs4o1Hh7oRkXL61tYtcdQhMPrH9IEv9XO8ppeeMdnlSPV53TJ+lfsXkCkL4QJe/+efv/GdRpgtLcU5+szjjT/u+cjo2IKM+BvXJBbqeo8SgfdKBIf9X1vxmkJWoT5OkobBC6KGMKtNU/WVPtPz2focWgWfSI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765984350; c=relaxed/simple; bh=v4iMRnfjjaJ+cTFraqW8xE5EFsGs//9Z8II0gJzJMeM=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=MX/cX1AWDK0MxpJSXQk90jqRgHpZOj26XIxqq99/wODCWgDB9ENVEGnk0zlBJ3DEjas74VfYezV/MWIwF8Aftjh9cGtmBlQ/HlkHuJQ6pWE01GJgIixlTK7TGPK3GGc8v4Vzb43sKyamOVL71DvckszGqxBeYTYyaJLa1lgtAeE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: c2360be2db5a11f0a38c85956e01ac42-20251217 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.6,REQID:103571b8-3570-4dcd-a117-4b06b511d359,IP:0,UR L:0,TC:0,Content:-25,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:-25 X-CID-META: VersionHash:a9d874c,CLOUDID:c820d83abc7cff5adbf79ca67a181cfa,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:102|123|850|898,TC:nil,Content:0|15|50,E DM:-3,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA :0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: c2360be2db5a11f0a38c85956e01ac42-20251217 X-User: tanze@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1945369742; Wed, 17 Dec 2025 23:12:10 +0800 From: tanze@kylinos.cn To: xry111@xry111.site, james.morse@arm.com, catalin.marinas@arm.com, maz@kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, tanze Subject: [PATCH v1] arm64/mpam: Replace the arm64.nompam parameter with arm64.mpam Date: Wed, 17 Dec 2025 23:11:59 +0800 Message-Id: <20251217151159.1076002-1-tanze@kylinos.cn> X-Mailer: git-send-email 2.25.1 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" From: tanze In practical application scenarios, some manufacturers use outdated firmware and do not add relevant configurations to the kernel command line during deployment, which will result in system boot failure. For manufacturers, disabling the MPAM feature by default and enabling it via additional boot parameters only when required is a more effective way to ensure compatibility. Fixes: 10f885d63a0e ("arm64: Add override for MPAM") Signed-off-by: tanze --- Documentation/admin-guide/kernel-parameters.txt | 6 +++--- arch/arm64/kernel/pi/idreg-override.c | 8 +++++++- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index a8d0afde7f85..c10d9529147c 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -556,9 +556,6 @@ Kernel parameters arm64.nomops [ARM64] Unconditionally disable Memory Copy and Memory Set instructions support =20 - arm64.nompam [ARM64] Unconditionally disable Memory Partitioning And - Monitoring support - arm64.nomte [ARM64] Unconditionally disable Memory Tagging Extension support =20 @@ -571,6 +568,9 @@ Kernel parameters arm64.nosve [ARM64] Unconditionally disable Scalable Vector Extension support =20 + arm64.mpam [ARM64] Unconditionally enable Memory Partitioning And + Monitoring support + ataflop=3D [HW,M68k] =20 atarimouse=3D [HW,MOUSE] Atari Mouse diff --git a/arch/arm64/kernel/pi/idreg-override.c b/arch/arm64/kernel/pi/i= dreg-override.c index bc57b290e5e7..f4e3972155c4 100644 --- a/arch/arm64/kernel/pi/idreg-override.c +++ b/arch/arm64/kernel/pi/idreg-override.c @@ -248,7 +248,7 @@ static const struct { { "rodata=3Doff", "arm64_sw.rodataoff=3D1" }, { "arm64.nolva", "id_aa64mmfr2.varange=3D0" }, { "arm64.no32bit_el0", "id_aa64pfr0.el0=3D1" }, - { "arm64.nompam", "id_aa64pfr0.mpam=3D0 id_aa64pfr1.mpam_frac=3D0" }, + { "arm64.mpam", "id_aa64pfr0.mpam=3D1 id_aa64pfr1.mpam_frac=3D1" }, }; =20 static int __init parse_hexdigit(const char *p, u64 *v) @@ -409,6 +409,12 @@ void __init init_feature_override(u64 boot_status, con= st void *fdt, =20 __boot_status =3D boot_status; =20 + /* + * Set the boot parameter to disable the MPAM feature, + * thus avoiding system boot failure. + */ + match_options("id_aa64pfr0.mpam=3D0 id_aa64pfr1.mpam_frac=3D0"); + parse_cmdline(fdt, chosen); =20 for (i =3D 0; i < ARRAY_SIZE(regs); i++) { --=20 2.25.1