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 83D26C4345F for ; Wed, 1 May 2024 14:47:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E56D96B0088; Wed, 1 May 2024 10:47:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E06A46B0089; Wed, 1 May 2024 10:47:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CA81A6B008C; Wed, 1 May 2024 10:47:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id AAFBF6B0088 for ; Wed, 1 May 2024 10:47:31 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 13C4F1C03F3 for ; Wed, 1 May 2024 14:47:31 +0000 (UTC) X-FDA: 82070105502.30.FB1348B Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf11.hostedemail.com (Postfix) with ESMTP id B7FB140019 for ; Wed, 1 May 2024 14:47:28 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=B+JDvGWe; spf=pass (imf11.hostedemail.com: domain of rppt@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1714574849; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=RNvRsc3B3nKLyGDvWTZyT1+l4UCZIoqyESBrinaENyQ=; b=pYa1cd7najyfFzC2awGX8KuU0zTYqTfR7tgYleSfgoyMVzfIgE801dmaKJbVoNbToQSa9T 5yCGKcsbvcX9voyJOawGH+HaWtLP3Qfcj0iSpPBfJhwCpR4j2goXWMUogbNtUhzenZ5yQH cXoPE3RpC76f0TDhiX8MQS7r+upjY0Y= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=B+JDvGWe; spf=pass (imf11.hostedemail.com: domain of rppt@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1714574849; a=rsa-sha256; cv=none; b=vsdy+9ISFP107LmwqEpVg+VnIqPsUspQr6m7d+8VpU/Wlhfsh953FwXFYPHMtatf1xiDjS VwIh3Ne3/HC5iG0TTXCcFsFfIG6mC/CQh/sQVuHbZjqHa2arPIlUT+rheUGUlhNFawmWl1 TBdNL5y7dhxyvS7dwXgXK+X/NLW/C8I= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 95830CE109D; Wed, 1 May 2024 14:47:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C68DC072AA; Wed, 1 May 2024 14:47:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714574842; bh=CxsjO+HboT5eCDqADgM4r/KpEYfbC3WzDJ+JdCdDWXM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=B+JDvGWeiBPw+HG1hQllCw3rfJnF5mRHzQWJfYyVSdBnJeLo7AnBOHdKkuoGmKsHV qWzIyIOfihVax38aOS+SQFJCa04Pg6k/PKHdS78FnNhpPx0Q7h/4fdlmkbJQeszChb EIiTbSxcUuDz+zQZlfmHW/bzb18nVHNLU6E/IN359z2k0CYTIl1DLmdRTVH2RexV/9 CPAhScPdfqxzR3mALBaqDIaoV4ebN/V38X67L1EqbysDjO6YW1JtrE90edXoZMLrm0 XgonsNZ2vYedRTvQTybLYYZd23v2s7lXDWvCqz/E2oz/BXLCtP1sriqxNEltkCVH9w 3GWsjlCazIa5A== Date: Wed, 1 May 2024 17:45:49 +0300 From: Mike Rapoport To: Steven Rostedt Cc: "Guilherme G. Piccoli" , "Luck, Tony" , Kees Cook , Joel Fernandes , "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 , "linux-hardening@vger.kernel.org" , Guenter Roeck , Ross Zwisler , "wklin@google.com" , Vineeth Remanan Pillai , Suleiman Souhlal , Linus Torvalds , Catalin Marinas , Will Deacon Subject: Re: [POC][RFC][PATCH 0/2] pstore/mm/x86: Add wildcard memmap to map pstore consistently Message-ID: References: <20240409210254.660888920@goodmis.org> <20240409172358.34ea19f0@gandalf.local.home> <202404091519.B7B2221@keescook> <3391c693-cf54-526b-79a8-d565e7140947@igalia.com> <20240411154007.5bdf8d95@gandalf.local.home> <20240412132243.053ad096@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240412132243.053ad096@gandalf.local.home> X-Rspam-User: X-Rspamd-Queue-Id: B7FB140019 X-Rspamd-Server: rspam06 X-Stat-Signature: ftc4d7dcqfozdf5gp7s1f44c9c8s4p7h X-HE-Tag: 1714574848-211425 X-HE-Meta: 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 +T70gFpN wCYu09hgHKXXsprl8mlE/3yV2t3OEf57F2YOHkAtRN+3fGw+VsKgYcFjcLRot+SVgW+HGhPEPO2k7xImxMsXQufIeYjw9WzmT+kjsIz4RKWajhjAPlFa8Jfn6SwzGjDpjRISomhC3oq8YFXCqt9DTZex3qGSnxTElvaXX+VR5RuD8RW8EF4+8GLaZA7MSo0+Y7BTMLwe9iU9HLmEOAvoYmdNvct49p9e2dTQtd3sOlIZFq5Q6aeVAno/uFea8gGQEZY5Y15Gq+yY9kntmlVoHDNStTecMONmX0qbL 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 Fri, Apr 12, 2024 at 01:22:43PM -0400, Steven Rostedt wrote: > On Fri, 12 Apr 2024 09:17:18 -0300 > "Guilherme G. Piccoli" wrote: > > > Thanks Steve, seems a good idea. With that, I could test on kdumpst (the > > tool used on Steam Deck), since it relies on modular pstore/ram. > > Something like this could work. > > -- Steve > > diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c > index a8831ef30c73..878aee8b2399 100644 > --- a/arch/x86/kernel/e820.c > +++ b/arch/x86/kernel/e820.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -64,61 +65,6 @@ struct e820_table *e820_table __refdata = &e820_table_init; > struct e820_table *e820_table_kexec __refdata = &e820_table_kexec_init; > struct e820_table *e820_table_firmware __refdata = &e820_table_firmware_init; > > -/* For wildcard memory requests, have a table to find them later */ > -#define E820_MAX_MAPS 8 > -#define E820_MAP_NAME_SIZE 16 > -struct e820_mmap_map { > - char name[E820_MAP_NAME_SIZE]; > - u64 start; > - u64 size; > -}; > -static struct e820_mmap_map e820_mmap_list[E820_MAX_MAPS] __initdata; > -static int e820_mmap_size __initdata; > - > -/* Add wildcard region with a lookup name */ > -static int __init e820_add_mmap(u64 start, u64 size, const char *name) > -{ > - struct e820_mmap_map *map; > - > - if (!name || !name[0] || strlen(name) >= E820_MAP_NAME_SIZE) > - return -EINVAL; > - > - if (e820_mmap_size >= E820_MAX_MAPS) > - return -1; > - > - map = &e820_mmap_list[e820_mmap_size++]; > - map->start = start; > - map->size = size; > - strcpy(map->name, name); > - return 0; > -} > - > -/** > - * memmap_named - Find a wildcard region with a given name > - * @name: The name that is attached to a wildcard region > - * @start: If found, holds the start address > - * @size: If found, holds the size of the address. > - * > - * Returns: 1 if found or 0 if not found. > - */ > -int __init memmap_named(const char *name, u64 *start, u64 *size) > -{ > - struct e820_mmap_map *map; > - int i; > - > - for (i = 0; i < e820_mmap_size; i++) { > - map = &e820_mmap_list[i]; > - if (!map->size) > - continue; > - if (strcmp(name, map->name) == 0) { > - *start = map->start; > - *size = map->size; > - return 1; > - } > - } > - return 0; > -} > - > /* For PCI or other memory-mapped resources */ > unsigned long pci_mem_start = 0xaeedbabe; > #ifdef CONFIG_PCI > @@ -1024,6 +970,8 @@ static int __init parse_memmap_one(char *p) > e820__range_add(start_at, mem_size, E820_TYPE_RESERVED); > } else if (*p == '*') { > u64 align; > + int ret; > + > /* Followed by alignment and ':' then the name */ > align = memparse(p+1, &p); > start_at = e820__region(mem_size, align); > @@ -1032,9 +980,10 @@ static int __init parse_memmap_one(char *p) > if (*p != ':') > return -EINVAL; > p++; > - e820_add_mmap(start_at, mem_size, p); > + ret = memmap_add(start_at, mem_size, p); > p += strlen(p); > - e820__range_add(start_at, mem_size, E820_TYPE_RESERVED); > + if (!ret) > + e820__range_add(start_at, mem_size, E820_TYPE_RESERVED); > } else if (*p == '!') { > start_at = memparse(p+1, &p); > e820__range_add(start_at, mem_size, E820_TYPE_PRAM); > diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c > index c200388399fb..22d2e2731dc2 100644 > --- a/fs/pstore/ram.c > +++ b/fs/pstore/ram.c > @@ -919,7 +919,6 @@ static void __init ramoops_register_dummy(void) > { > struct ramoops_platform_data pdata; > > -#ifndef MODULE > /* Only allowed when builtin */ > if (mem_name) { > u64 start; > @@ -930,7 +929,6 @@ static void __init ramoops_register_dummy(void) > mem_size = size; > } > } > -#endif > > /* > * Prepare a dummy platform data structure to carry the module > diff --git a/include/linux/mm.h b/include/linux/mm.h > index cf9b34454c6f..6ce1c6929d1f 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -4203,5 +4203,6 @@ static inline bool pfn_is_unaccepted_memory(unsigned long pfn) > } > > int memmap_named(const char *name, u64 *start, u64 *size); > +int memmap_add(long start, long size, const char *name); > > #endif /* _LINUX_MM_H */ > diff --git a/mm/memory.c b/mm/memory.c > index 7a29f17df7c1..fe054e1bb678 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -120,12 +120,6 @@ static bool vmf_orig_pte_uffd_wp(struct vm_fault *vmf) > return pte_marker_uffd_wp(vmf->orig_pte); > } > > -int __init __weak memmap_named(const char *name, u64 *start, u64 *size) > -{ > - pr_info("Kernel command line: memmap=nn*align:name not supported on this kernel"); > - /* zero means not found */ > - return 0; > -} > > /* > * A number of key systems in x86 including ioremap() rely on the assumption > diff --git a/mm/mm_init.c b/mm/mm_init.c > index 549e76af8f82..e5b729b83fdc 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -154,6 +154,77 @@ static __init int set_mminit_loglevel(char *str) > early_param("mminit_loglevel", set_mminit_loglevel); > #endif /* CONFIG_DEBUG_MEMORY_INIT */ > > +/* For wildcard memory requests, have a table to find them later */ > +#define MAX_MAPS 8 > +#define MAP_NAME_SIZE 16 > +struct mmap_map { > + char name[MAP_NAME_SIZE]; > + long start; > + long size; > +}; > +static struct mmap_map early_mmap_list[MAX_MAPS] __initdata; > +static int early_mmap_size __initdata; > +static struct mmap_map *mmap_list; > + > +/* Add wildcard region with a lookup name */ > +int memmap_add(long start, long size, const char *name) > +{ > + struct mmap_map *map; > + > + if (!name || !name[0] || strlen(name) >= MAP_NAME_SIZE) > + return -EINVAL; > + > + if (early_mmap_size >= MAX_MAPS) > + return -1; > + > + map = &early_mmap_list[early_mmap_size++]; > + map->start = start; > + map->size = size; > + strcpy(map->name, name); > + return 0; > +} > + > +static void __init memmap_copy(void) > +{ > + if (!early_mmap_size) > + return; > + > + mmap_list = kcalloc(early_mmap_size + 1, sizeof(mmap_list), GFP_KERNEL); We can keep early_mmap_size after boot and then we don't need to allocate an extra element in the mmap_list. No strong feeling here, though. > + if (!mmap_list) > + return; > + > + for (int i = 0; i < early_mmap_size; i++) > + mmap_list[i] = early_mmap_list[i]; > +} With something like this /* * Parse early_reserve_mem=nn:align:name */ static int __init early_reserve_mem(char *p) { phys_addr_t start, size, align; char *oldp; int err; if (!p) return -EINVAL; oldp = p; size = memparse(p, &p); if (p == oldp) return -EINVAL; if (*p != ':') return -EINVAL; align = memparse(p+1, &p); if (*p != ':') return -EINVAL; start = memblock_phys_alloc(size, align); if (!start) return -ENOMEM; p++; err = memmap_add(start, size, p); if (err) { memblock_phys_free(start, size); return err; } p += strlen(p); return *p == '\0' ? 0: -EINVAL; } __setup("early_reserve_mem=", early_reserve_mem); you don't need to touch e820 and it will work the same for all architectures. We'd need a better naming, but I couldn't think of something better yet. > + > +/** > + * memmap_named - Find a wildcard region with a given name > + * @name: The name that is attached to a wildcard region > + * @start: If found, holds the start address > + * @size: If found, holds the size of the address. > + * > + * Returns: 1 if found or 0 if not found. > + */ > +int memmap_named(const char *name, u64 *start, u64 *size) > +{ > + struct mmap_map *map; > + > + if (!mmap_list) > + return 0; > + > + for (int i = 0; mmap_list[i].name[0]; i++) { > + map = &mmap_list[i]; > + if (!map->size) > + continue; > + if (strcmp(name, map->name) == 0) { > + *start = map->start; > + *size = map->size; > + return 1; > + } > + } > + return 0; > +} > + > struct kobject *mm_kobj; > > #ifdef CONFIG_SMP > @@ -2793,4 +2864,5 @@ void __init mm_core_init(void) > pti_init(); > kmsan_init_runtime(); > mm_cache_init(); > + memmap_copy(); > } -- Sincerely yours, Mike.