From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50EB7C27C65 for ; Tue, 11 Jun 2024 22:36:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D24616B0104; Tue, 11 Jun 2024 18:36:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CACAF6B0105; Tue, 11 Jun 2024 18:36:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B27E26B0106; Tue, 11 Jun 2024 18:36:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 939896B0104 for ; Tue, 11 Jun 2024 18:36:33 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 317341609BF for ; Tue, 11 Jun 2024 22:36:33 +0000 (UTC) X-FDA: 82220068266.11.3120970 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf02.hostedemail.com (Postfix) with ESMTP id 810EB80002 for ; Tue, 11 Jun 2024 22:36:31 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf02.hostedemail.com: domain of "SRS0=hOOK=NN=goodmis.org=rostedt@kernel.org" designates 139.178.84.217 as permitted sender) smtp.mailfrom="SRS0=hOOK=NN=goodmis.org=rostedt@kernel.org" ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1718145391; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XuR9Jv6N8rFckFCZYDxz8ldE5lfU6ItJ8o6UFf0VQuc=; b=P5HAJhUL6Pix625MqjpsTb2TIjOv+lIPljrUW+LckX4oVFGPeVCcX4ZoKf4a7QBQYu2OBH bgbkoLMcR860zokaerWTT2wU00dlyBDSDWq+sqNtJSke3bD9bHNXeKZV5uXIpxmzDCMTdC G4nzv17AZvKmAlEKXF/euw7u3jnwZn0= ARC-Authentication-Results: i=1; imf02.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf02.hostedemail.com: domain of "SRS0=hOOK=NN=goodmis.org=rostedt@kernel.org" designates 139.178.84.217 as permitted sender) smtp.mailfrom="SRS0=hOOK=NN=goodmis.org=rostedt@kernel.org" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1718145391; a=rsa-sha256; cv=none; b=jQnuNJhs3ZCEKDfklzDQz9R65MA5wOKMV80a6J8LRpsQunOakr3M5HcEOPhY//BbuCuGMs s2TKCDQu7QVNiEXXoemS7bJuWpFUVoup7W29rmxfAUbyKMxOxv0EgLg/HBvJegKFoei0nQ cDFYEH5L6RaqYE8b95PLxLClh2Z7O5Q= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 88434611F1; Tue, 11 Jun 2024 22:36:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E625CC2BD10; Tue, 11 Jun 2024 22:36:26 +0000 (UTC) Date: Tue, 11 Jun 2024 18:36:43 -0400 From: Steven Rostedt To: Guenter Roeck Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Lorenzo Stoakes , linux-mm@kvack.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Peter Zijlstra , Kees Cook , Tony Luck , "Guilherme G. Piccoli" , linux-hardening@vger.kernel.org, Ross Zwisler , wklin@google.com, Vineeth Remanan Pillai , Joel Fernandes , Suleiman Souhlal , Linus Torvalds , Catalin Marinas , Will Deacon , Ard Biesheuvel , Mike Rapoport Subject: Re: [PATCH v4 1/2] mm/memblock: Add "reserve_mem" to reserved named memory at boot up Message-ID: <20240611183643.0327ef5b@gandalf.local.home> In-Reply-To: References: <20240611215610.548854415@goodmis.org> <20240611215801.443593152@goodmis.org> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 810EB80002 X-Stat-Signature: g5rydyg9ntzbe6fgrxctsare3u33w53p X-Rspam-User: X-HE-Tag: 1718145391-328661 X-HE-Meta: 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 Pvrcjvuc p+o2MzJXPCv6zgWtaP3yF4CNxJPKGTpMx2lg1fCepYUitRwL40MZZHJzcEEXh4NqIhjoeUfaDF40NRcqAWVH5a99BFHThkKQWe5Kf4XyPQJydHMM+KzbWu2TwFoxYbZoPYpJC7ihZiF/RRm4cF3dhmPah+IdcjiWhMBHLDjlNc/vKQ+l06nUkIw2n6tHALencsK5VnjjkSQKE6iNSCRNoI75mLTRxsPHs7CUzafVb7YqLPqtz4OHkTl8x+SJ94oM9cYLb604ki6jdulTSXiRhKjV+d0dae4euxT8LNnT58X2jG1n+XtN9a7IlznSpkpct+NTRDVaAGyR/6pdJ7FqS3pFT9zfcPDSKkvuOOqrlf4gWrR8= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, 11 Jun 2024 15:26:05 -0700 Guenter Roeck wrote: > > diff --git a/mm/memblock.c b/mm/memblock.c > > index d09136e040d3..044ddce8f085 100644 > > --- a/mm/memblock.c > > +++ b/mm/memblock.c > > @@ -2244,6 +2244,121 @@ void __init memblock_free_all(void) > > totalram_pages_add(pages); > > } > > > > +/* Keep a table to reserve named memory */ > > +#define RESERVE_MEM_MAX_ENTRIES 8 > > +#define RESERVE_MEM_NAME_SIZE 16 > > +struct reserve_mem_table { > > + char name[RESERVE_MEM_NAME_SIZE]; > > + phys_addr_t start; > > + phys_addr_t size; > > +}; > > +static struct reserve_mem_table reserved_mem_table[RESERVE_MEM_MAX_ENTRIES]; > > +static int reserved_mem_count; > > + > > +/* Add wildcard region with a lookup name */ > > +static int __init reserved_mem_add(phys_addr_t start, phys_addr_t size, > > + const char *name) > > +{ > > + struct reserve_mem_table *map; > > + > > + if (!name || !name[0] || strlen(name) >= RESERVE_MEM_NAME_SIZE) > > + return -EINVAL; > > + > > I know I am picky, but name is never NULL, and strlen(name) is guaranteed to be > 0. > Personally I'd suggest to check for strlen(name) >= RESERVE_MEM_NAME_SIZE together > with !strlen(name) and drop the duplicate checks here (and, as side effect, avoid > the pointless memory allocation if the name is invalid). Yeah, it's now checked before hand. I'll remove it for v5. > > > + if (reserved_mem_count >= RESERVE_MEM_MAX_ENTRIES) > > + return -1; > > + > > + map = &reserved_mem_table[reserved_mem_count++]; > > + map->start = start; > > + map->size = size; > > + strscpy(map->name, name); > > + return 0; > > +} > > + > > +/* > > + * Parse reserve_mem=nn:align:name > > + */ > > +static int __init reserve_mem(char *p) > > +{ > > + phys_addr_t start, size, align; > > + char *name; > > + char *oldp; > > + int err; > > + > > + if (!p) > > + return -EINVAL; > > + > > + oldp = p; > > + size = memparse(p, &p); > > + if (!size || p == oldp) > > + return -EINVAL; > > + > > + if (*p != ':') > > + return -EINVAL; > > + > > + align = memparse(p+1, &p); > > + if (*p != ':') > > + return -EINVAL; > > + > > + /* > > + * memblock_phys_alloc() doesn't like a zero size align, > > + * but it is OK for this command to have it. > > + */ > > + if (align <= SMP_CACHE_BYTES) > > Any reason for using <= instead of < ? Nope. Not sure why I did that. :-/ I'll fix that too. Thanks, -- Steve > > Guenter > > > + align = SMP_CACHE_BYTES; > > + > > + name = p + 1; > > + if (!strlen(name)) > > + return -EINVAL; > > + > > + /* Make sure that name has text */ > > + for (p = name; *p; p++) { > > + if (!isspace(*p)) > > + break; > > + } > > + if (!*p) > > + return -EINVAL; > > + > > + start = memblock_phys_alloc(size, align); > > + if (!start) > > + return -ENOMEM; > > + > > + err = reserved_mem_add(start, size, name); > > + if (err) { > > + memblock_phys_free(start, size); > > + return err; > > + } > > + > > + return 0; > > +} > > +__setup("reserve_mem=", reserve_mem); > > + > > #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK) > > static const char * const flagname[] = { > > [ilog2(MEMBLOCK_HOTPLUG)] = "HOTPLUG",