From nobody Fri Apr 3 06:41:35 2026 Received: from fanzine2.igalia.com (fanzine2.igalia.com [213.97.179.56]) (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 7B98A378814 for ; Tue, 17 Feb 2026 19:58:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.97.179.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771358333; cv=none; b=iwQlQE4F4ISAqoaJTxJJ6h+IMdvThq9QmZpOJnAYXScqyLVwIhHFd14sRvcbQBSgwk/MmaW3buCc+/qj/lINtdHEmXqGgjlyko98bN6ZfMIiIDe95loh/vtUxlWeXJCPk51WnR9OUYDI7SDzXTa672DKiXAtVL2r4IKf0bmE6lA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771358333; c=relaxed/simple; bh=9JqGs394cOl+sFrE2NHwxlB4jeThJ0h+Bs5IcjhMtIQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KRkXYejhODUC7++SsJJo17BgKgCE8bT0gLI+R3eVp3/NS37RHgKndHX78KtzmOyDXpmLw52n9rggsEyFy1zsaotzsPKP8Qy309EKCsHItPeqeGMeX73JHZ7G9t9OxA+g9k7gNYBEGLo+qASadq8YibdiXUHqQZ7Fnhi0p3Kx7J8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com; spf=pass smtp.mailfrom=igalia.com; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b=LaqiP1tK; arc=none smtp.client-ip=213.97.179.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=igalia.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=igalia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="LaqiP1tK" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=RXuAwV7EvPnrzwYm1Nj10RW4qIvW3kT9YlwlXXuuzFI=; b=LaqiP1tKNet3KRNu+1d8iYOjO3 2lVUrYVDdGpWPsZ/HTe/NbzLZ6AqlI4ETF3MXFNCy500uMdTck8cpWYjuRHT2cSVxfNarRCim54rt TBydzckayuRqC1JqqxucOk+jiV/EHiVMtJIJ62wq6Rsk9V9C0Cn9RoAw0GwvdgiV4ijVufKMJXYN8 pqsoOi0m77R1RAfjUUbvfUqL97ViqvAjR+fytqhD/RYzOyj0nDWpYRfC2DAvuFemlBwFTwK/Z44tM NGxrEJrIzMFgjn33UHOwiKdorOJGxT4LqhdZEnGDwXEhuHyu1f9mxZKMGdvxq7VQ09oMVPnUHBk/u W2Vvp5YQ==; Received: from [177.45.213.208] (helo=localhost) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1vsRDX-001nLA-3A; Tue, 17 Feb 2026 20:58:43 +0100 From: "Guilherme G. Piccoli" To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, kernel-dev@igalia.com, kernel@gpiccoli.net, gpiccoli@igalia.com, Andrew Morton , Mike Rapoport , Steven Rostedt Subject: [PATCH 1/2] mm/memblock: Print out errors on reserve_mem parser Date: Tue, 17 Feb 2026 16:45:06 -0300 Message-ID: <20260217195816.861684-2-gpiccoli@igalia.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260217195816.861684-1-gpiccoli@igalia.com> References: <20260217195816.861684-1-gpiccoli@igalia.com> 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" The parsing of kernel parameter "reserve_mem=3D" is subject to multiple failures, like duplicate naming, malformed expression or even lack of available memory. Right now, all of these fail silently. Let's add some messages so the kernel log can provide useful information in case of failures. Cc: Andrew Morton Cc: Mike Rapoport Cc: Steven Rostedt Signed-off-by: Guilherme G. Piccoli --- mm/memblock.c | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-) diff --git a/mm/memblock.c b/mm/memblock.c index b3ddfdec7a80..2d2646f7a120 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -2642,23 +2642,25 @@ static int __init reserve_mem(char *p) int len; =20 if (!p) - return -EINVAL; + goto err_param; =20 /* Check if there's room for more reserved memory */ - if (reserved_mem_count >=3D RESERVE_MEM_MAX_ENTRIES) + if (reserved_mem_count >=3D RESERVE_MEM_MAX_ENTRIES) { + pr_err("reserve_mem: no more room for reserved memory\n"); return -EBUSY; + } =20 oldp =3D p; size =3D memparse(p, &p); if (!size || p =3D=3D oldp) - return -EINVAL; + goto err_param; =20 if (*p !=3D ':') - return -EINVAL; + goto err_param; =20 align =3D memparse(p+1, &p); if (*p !=3D ':') - return -EINVAL; + goto err_param; =20 /* * memblock_phys_alloc() doesn't like a zero size align, @@ -2672,7 +2674,7 @@ static int __init reserve_mem(char *p) =20 /* name needs to have length but not too big */ if (!len || len >=3D RESERVE_MEM_NAME_SIZE) - return -EINVAL; + goto err_param; =20 /* Make sure that name has text */ for (p =3D name; *p; p++) { @@ -2680,11 +2682,13 @@ static int __init reserve_mem(char *p) break; } if (!*p) - return -EINVAL; + goto err_param; =20 /* Make sure the name is not already used */ - if (reserve_mem_find_by_name(name, &start, &tmp)) + if (reserve_mem_find_by_name(name, &start, &tmp)) { + pr_err("reserve_mem: name \"%s\" was already used\n", name); return -EBUSY; + } =20 /* Pick previous allocations up from KHO if available */ if (reserve_mem_kho_revive(name, size, align)) @@ -2692,12 +2696,18 @@ static int __init reserve_mem(char *p) =20 /* TODO: Allocation must be outside of scratch region */ start =3D memblock_phys_alloc(size, align); - if (!start) + if (!start) { + pr_err("reserve_mem: memblock allocation failed\n"); return -ENOMEM; + } =20 reserved_mem_add(start, size, name); =20 return 1; +err_param: + pr_err("reserve_mem: empty or malformed parameter\n"); + return -EINVAL; + } __setup("reserve_mem=3D", reserve_mem); =20 --=20 2.50.1