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 X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D5CCC433EB for ; Mon, 20 Jul 2020 09:26:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 541A420684 for ; Mon, 20 Jul 2020 09:26:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595237168; bh=xIW2F2IJFqxTzMmaAs6C8+3yiJvBuUFpN7ht+vECA5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=nZ5iljAKMyjD2h6tfRSeVERFdu9TMKf09UOjn1us8sHrSS1PsKq95sEfl01uXklPG s/RunGnEnio6cjcAbK/M4AlFNa7VJBSyBlhfiUs4Ewk9mAOolX9/X0XHQ66gypA5yN 5LeL7iWfzPopsiM/9oxrJLlysO8CET5GaFn2fnZM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728153AbgGTJ0B (ORCPT ); Mon, 20 Jul 2020 05:26:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:40148 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728115AbgGTJ0B (ORCPT ); Mon, 20 Jul 2020 05:26:01 -0400 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C6D012176B; Mon, 20 Jul 2020 09:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595237160; bh=xIW2F2IJFqxTzMmaAs6C8+3yiJvBuUFpN7ht+vECA5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rrNLOpGtsBkLwzoA0ZoHKqviCVJ3KJRCdTwu93rSdZ36ELhztooGsQ2e4T8KUYbwf g95kfDYYhWT0rijSXjiKDluNKSd11vd3VHc2VWrEE5zvJz5wMrVk6WVbraWxItZhwN Z/wN2S6aNtjO+InKcFYziVst7pgrShtls+s5WRPo= From: Mike Rapoport To: linux-kernel@vger.kernel.org Cc: Alexander Viro , Andrew Morton , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dan Williams , Dave Hansen , Elena Reshetova , "H. Peter Anvin" , Idan Yaniv , Ingo Molnar , James Bottomley , "Kirill A. Shutemov" , Matthew Wilcox , Mike Rapoport , Mike Rapoport , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Thomas Gleixner , Tycho Andersen , Will Deacon , linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, linux-riscv@lists.infradead.org, x86@kernel.org Subject: [PATCH 6/6] mm: secretmem: add ability to reserve memory at boot Date: Mon, 20 Jul 2020 12:24:35 +0300 Message-Id: <20200720092435.17469-7-rppt@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200720092435.17469-1-rppt@kernel.org> References: <20200720092435.17469-1-rppt@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-api-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org From: Mike Rapoport Taking pages out from the direct map and bringing them back may create undesired fragmentation and usage of the smaller pages in the direct mapping of the physical memory. This can be avoided if a significantly large area of the physical memory would be reserved for secretmem purposes at boot time. Add ability to reserve physical memory for secretmem at boot time using "secretmem" kernel parameter and then use that reserved memory as a global pool for secret memory needs. Signed-off-by: Mike Rapoport --- mm/secretmem.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 126 insertions(+), 8 deletions(-) diff --git a/mm/secretmem.c b/mm/secretmem.c index dce56f84968f..322f425dbb22 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -30,6 +31,39 @@ struct secretmem_ctx { unsigned int mode; }; +struct secretmem_pool { + struct gen_pool *pool; + unsigned long reserved_size; + void *reserved; +}; + +static struct secretmem_pool secretmem_pool; + +static struct page *secretmem_alloc_huge_page(gfp_t gfp) +{ + struct gen_pool *pool = secretmem_pool.pool; + unsigned long addr = 0; + struct page *page = NULL; + + if (pool) { + if (gen_pool_avail(pool) < PMD_SIZE) + return NULL; + + addr = gen_pool_alloc(pool, PMD_SIZE); + if (!addr) + return NULL; + + page = virt_to_page(addr); + } else { + page = alloc_pages(gfp, PMD_PAGE_ORDER); + + if (page) + split_page(page, PMD_PAGE_ORDER); + } + + return page; +} + static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER); @@ -38,12 +72,11 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) struct page *page; int err; - page = alloc_pages(gfp, PMD_PAGE_ORDER); + page = secretmem_alloc_huge_page(gfp); if (!page) return -ENOMEM; addr = (unsigned long)page_address(page); - split_page(page, PMD_PAGE_ORDER); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); if (err) { @@ -266,11 +299,13 @@ SYSCALL_DEFINE1(secretmemfd, unsigned long, flags) return err; } -static void secretmem_cleanup_chunk(struct gen_pool *pool, - struct gen_pool_chunk *chunk, void *data) +static void secretmem_recycle_range(unsigned long start, unsigned long end) +{ + gen_pool_free(secretmem_pool.pool, start, PMD_SIZE); +} + +static void secretmem_release_range(unsigned long start, unsigned long end) { - unsigned long start = chunk->start_addr; - unsigned long end = chunk->end_addr; unsigned long nr_pages, addr; nr_pages = (end - start + 1) / PAGE_SIZE; @@ -280,6 +315,18 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, put_page(virt_to_page(addr)); } +static void secretmem_cleanup_chunk(struct gen_pool *pool, + struct gen_pool_chunk *chunk, void *data) +{ + unsigned long start = chunk->start_addr; + unsigned long end = chunk->end_addr; + + if (secretmem_pool.pool) + secretmem_recycle_range(start, end); + else + secretmem_release_range(start, end); +} + static void secretmem_cleanup_pool(struct secretmem_ctx *ctx) { struct gen_pool *pool = ctx->pool; @@ -319,14 +366,85 @@ static struct file_system_type secretmem_fs = { .kill_sb = kill_anon_super, }; +static int secretmem_reserved_mem_init(void) +{ + struct gen_pool *pool; + struct page *page; + void *addr; + int err; + + if (!secretmem_pool.reserved) + return 0; + + pool = gen_pool_create(PMD_SHIFT, NUMA_NO_NODE); + if (!pool) + return -ENOMEM; + + err = gen_pool_add(pool, (unsigned long)secretmem_pool.reserved, + secretmem_pool.reserved_size, NUMA_NO_NODE); + if (err) + goto err_destroy_pool; + + for (addr = secretmem_pool.reserved; + addr < secretmem_pool.reserved + secretmem_pool.reserved_size; + addr += PAGE_SIZE) { + page = virt_to_page(addr); + __ClearPageReserved(page); + set_page_count(page, 1); + } + + secretmem_pool.pool = pool; + page = virt_to_page(secretmem_pool.reserved); + __kernel_map_pages(page, secretmem_pool.reserved_size / PAGE_SIZE, 0); + return 0; + +err_destroy_pool: + gen_pool_destroy(pool); + return err; +} + static int secretmem_init(void) { - int ret = 0; + int ret; + + ret = secretmem_reserved_mem_init(); + if (ret) + return ret; secretmem_mnt = kern_mount(&secretmem_fs); - if (IS_ERR(secretmem_mnt)) + if (IS_ERR(secretmem_mnt)) { + gen_pool_destroy(secretmem_pool.pool); ret = PTR_ERR(secretmem_mnt); + } return ret; } fs_initcall(secretmem_init); + +static int __init secretmem_setup(char *str) +{ + phys_addr_t align = PMD_SIZE; + unsigned long reserved_size; + void *reserved; + + reserved_size = memparse(str, NULL); + if (!reserved_size) + return 0; + + if (reserved_size * 2 > PUD_SIZE) + align = PUD_SIZE; + + reserved = memblock_alloc(reserved_size, align); + if (!reserved) { + pr_err("failed to reserve %zu bytes\n", secretmem_pool.reserved_size); + return 0; + } + + secretmem_pool.reserved_size = reserved_size; + secretmem_pool.reserved = reserved; + + pr_info("reserved %zuM\n", reserved_size >> 20); + + return 1; +} +__setup("secretmem=", secretmem_setup); -- 2.26.2 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: [PATCH 6/6] mm: secretmem: add ability to reserve memory at boot Date: Mon, 20 Jul 2020 12:24:35 +0300 Message-ID: <20200720092435.17469-7-rppt@kernel.org> References: <20200720092435.17469-1-rppt@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Received: from mail.kernel.org ([198.145.29.99]:40148 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728115AbgGTJ0B (ORCPT ); Mon, 20 Jul 2020 05:26:01 -0400 In-Reply-To: <20200720092435.17469-1-rppt@kernel.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-kernel@vger.kernel.org Cc: Alexander Viro , Andrew Morton , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dan Williams , Dave Hansen , Elena Reshetova , "H. Peter Anvin" , Idan Yaniv , Ingo Molnar , James Bottomley , "Kirill A. Shutemov" , Matthew Wilcox , Mike Rapoport , Mike Rapoport , Palmer Dabbelt , Paul Walmsley From: Mike Rapoport Taking pages out from the direct map and bringing them back may create undesired fragmentation and usage of the smaller pages in the direct mapping of the physical memory. This can be avoided if a significantly large area of the physical memory would be reserved for secretmem purposes at boot time. Add ability to reserve physical memory for secretmem at boot time using "secretmem" kernel parameter and then use that reserved memory as a global pool for secret memory needs. Signed-off-by: Mike Rapoport --- mm/secretmem.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 126 insertions(+), 8 deletions(-) diff --git a/mm/secretmem.c b/mm/secretmem.c index dce56f84968f..322f425dbb22 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -30,6 +31,39 @@ struct secretmem_ctx { unsigned int mode; }; +struct secretmem_pool { + struct gen_pool *pool; + unsigned long reserved_size; + void *reserved; +}; + +static struct secretmem_pool secretmem_pool; + +static struct page *secretmem_alloc_huge_page(gfp_t gfp) +{ + struct gen_pool *pool = secretmem_pool.pool; + unsigned long addr = 0; + struct page *page = NULL; + + if (pool) { + if (gen_pool_avail(pool) < PMD_SIZE) + return NULL; + + addr = gen_pool_alloc(pool, PMD_SIZE); + if (!addr) + return NULL; + + page = virt_to_page(addr); + } else { + page = alloc_pages(gfp, PMD_PAGE_ORDER); + + if (page) + split_page(page, PMD_PAGE_ORDER); + } + + return page; +} + static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER); @@ -38,12 +72,11 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) struct page *page; int err; - page = alloc_pages(gfp, PMD_PAGE_ORDER); + page = secretmem_alloc_huge_page(gfp); if (!page) return -ENOMEM; addr = (unsigned long)page_address(page); - split_page(page, PMD_PAGE_ORDER); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); if (err) { @@ -266,11 +299,13 @@ SYSCALL_DEFINE1(secretmemfd, unsigned long, flags) return err; } -static void secretmem_cleanup_chunk(struct gen_pool *pool, - struct gen_pool_chunk *chunk, void *data) +static void secretmem_recycle_range(unsigned long start, unsigned long end) +{ + gen_pool_free(secretmem_pool.pool, start, PMD_SIZE); +} + +static void secretmem_release_range(unsigned long start, unsigned long end) { - unsigned long start = chunk->start_addr; - unsigned long end = chunk->end_addr; unsigned long nr_pages, addr; nr_pages = (end - start + 1) / PAGE_SIZE; @@ -280,6 +315,18 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, put_page(virt_to_page(addr)); } +static void secretmem_cleanup_chunk(struct gen_pool *pool, + struct gen_pool_chunk *chunk, void *data) +{ + unsigned long start = chunk->start_addr; + unsigned long end = chunk->end_addr; + + if (secretmem_pool.pool) + secretmem_recycle_range(start, end); + else + secretmem_release_range(start, end); +} + static void secretmem_cleanup_pool(struct secretmem_ctx *ctx) { struct gen_pool *pool = ctx->pool; @@ -319,14 +366,85 @@ static struct file_system_type secretmem_fs = { .kill_sb = kill_anon_super, }; +static int secretmem_reserved_mem_init(void) +{ + struct gen_pool *pool; + struct page *page; + void *addr; + int err; + + if (!secretmem_pool.reserved) + return 0; + + pool = gen_pool_create(PMD_SHIFT, NUMA_NO_NODE); + if (!pool) + return -ENOMEM; + + err = gen_pool_add(pool, (unsigned long)secretmem_pool.reserved, + secretmem_pool.reserved_size, NUMA_NO_NODE); + if (err) + goto err_destroy_pool; + + for (addr = secretmem_pool.reserved; + addr < secretmem_pool.reserved + secretmem_pool.reserved_size; + addr += PAGE_SIZE) { + page = virt_to_page(addr); + __ClearPageReserved(page); + set_page_count(page, 1); + } + + secretmem_pool.pool = pool; + page = virt_to_page(secretmem_pool.reserved); + __kernel_map_pages(page, secretmem_pool.reserved_size / PAGE_SIZE, 0); + return 0; + +err_destroy_pool: + gen_pool_destroy(pool); + return err; +} + static int secretmem_init(void) { - int ret = 0; + int ret; + + ret = secretmem_reserved_mem_init(); + if (ret) + return ret; secretmem_mnt = kern_mount(&secretmem_fs); - if (IS_ERR(secretmem_mnt)) + if (IS_ERR(secretmem_mnt)) { + gen_pool_destroy(secretmem_pool.pool); ret = PTR_ERR(secretmem_mnt); + } return ret; } fs_initcall(secretmem_init); + +static int __init secretmem_setup(char *str) +{ + phys_addr_t align = PMD_SIZE; + unsigned long reserved_size; + void *reserved; + + reserved_size = memparse(str, NULL); + if (!reserved_size) + return 0; + + if (reserved_size * 2 > PUD_SIZE) + align = PUD_SIZE; + + reserved = memblock_alloc(reserved_size, align); + if (!reserved) { + pr_err("failed to reserve %zu bytes\n", secretmem_pool.reserved_size); + return 0; + } + + secretmem_pool.reserved_size = reserved_size; + secretmem_pool.reserved = reserved; + + pr_info("reserved %zuM\n", reserved_size >> 20); + + return 1; +} +__setup("secretmem=", secretmem_setup); -- 2.26.2 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 X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B03D3C433EA for ; 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Mon, 20 Jul 2020 02:26:00 -0700 (PDT) Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C6D012176B; Mon, 20 Jul 2020 09:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595237160; bh=xIW2F2IJFqxTzMmaAs6C8+3yiJvBuUFpN7ht+vECA5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rrNLOpGtsBkLwzoA0ZoHKqviCVJ3KJRCdTwu93rSdZ36ELhztooGsQ2e4T8KUYbwf g95kfDYYhWT0rijSXjiKDluNKSd11vd3VHc2VWrEE5zvJz5wMrVk6WVbraWxItZhwN Z/wN2S6aNtjO+InKcFYziVst7pgrShtls+s5WRPo= From: Mike Rapoport To: linux-kernel@vger.kernel.org Subject: [PATCH 6/6] mm: secretmem: add ability to reserve memory at boot Date: Mon, 20 Jul 2020 12:24:35 +0300 Message-Id: <20200720092435.17469-7-rppt@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200720092435.17469-1-rppt@kernel.org> References: <20200720092435.17469-1-rppt@kernel.org> MIME-Version: 1.0 Message-ID-Hash: AE3RFBTPEEJXCJVA5LUF6Q5O3BT6FVBL X-Message-ID-Hash: AE3RFBTPEEJXCJVA5LUF6Q5O3BT6FVBL X-MailFrom: rppt@kernel.org X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Alexander Viro , Andrew Morton , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dave Hansen , Elena Reshetova , "H. Peter Anvin" , Idan Yaniv , Ingo Molnar , James Bottomley , "Kirill A. Shutemov" , Matthew Wilcox , Mike Rapoport , Mike Rapoport , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Thomas Gleixner , Tycho Andersen , Will Deacon , linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kv ack.org, linux-nvdimm@lists.01.org, linux-riscv@lists.infradead.org, x86@kernel.org X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit From: Mike Rapoport Taking pages out from the direct map and bringing them back may create undesired fragmentation and usage of the smaller pages in the direct mapping of the physical memory. This can be avoided if a significantly large area of the physical memory would be reserved for secretmem purposes at boot time. Add ability to reserve physical memory for secretmem at boot time using "secretmem" kernel parameter and then use that reserved memory as a global pool for secret memory needs. Signed-off-by: Mike Rapoport --- mm/secretmem.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 126 insertions(+), 8 deletions(-) diff --git a/mm/secretmem.c b/mm/secretmem.c index dce56f84968f..322f425dbb22 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -30,6 +31,39 @@ struct secretmem_ctx { unsigned int mode; }; +struct secretmem_pool { + struct gen_pool *pool; + unsigned long reserved_size; + void *reserved; +}; + +static struct secretmem_pool secretmem_pool; + +static struct page *secretmem_alloc_huge_page(gfp_t gfp) +{ + struct gen_pool *pool = secretmem_pool.pool; + unsigned long addr = 0; + struct page *page = NULL; + + if (pool) { + if (gen_pool_avail(pool) < PMD_SIZE) + return NULL; + + addr = gen_pool_alloc(pool, PMD_SIZE); + if (!addr) + return NULL; + + page = virt_to_page(addr); + } else { + page = alloc_pages(gfp, PMD_PAGE_ORDER); + + if (page) + split_page(page, PMD_PAGE_ORDER); + } + + return page; +} + static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER); @@ -38,12 +72,11 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) struct page *page; int err; - page = alloc_pages(gfp, PMD_PAGE_ORDER); + page = secretmem_alloc_huge_page(gfp); if (!page) return -ENOMEM; addr = (unsigned long)page_address(page); - split_page(page, PMD_PAGE_ORDER); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); if (err) { @@ -266,11 +299,13 @@ SYSCALL_DEFINE1(secretmemfd, unsigned long, flags) return err; } -static void secretmem_cleanup_chunk(struct gen_pool *pool, - struct gen_pool_chunk *chunk, void *data) +static void secretmem_recycle_range(unsigned long start, unsigned long end) +{ + gen_pool_free(secretmem_pool.pool, start, PMD_SIZE); +} + +static void secretmem_release_range(unsigned long start, unsigned long end) { - unsigned long start = chunk->start_addr; - unsigned long end = chunk->end_addr; unsigned long nr_pages, addr; nr_pages = (end - start + 1) / PAGE_SIZE; @@ -280,6 +315,18 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, put_page(virt_to_page(addr)); } +static void secretmem_cleanup_chunk(struct gen_pool *pool, + struct gen_pool_chunk *chunk, void *data) +{ + unsigned long start = chunk->start_addr; + unsigned long end = chunk->end_addr; + + if (secretmem_pool.pool) + secretmem_recycle_range(start, end); + else + secretmem_release_range(start, end); +} + static void secretmem_cleanup_pool(struct secretmem_ctx *ctx) { struct gen_pool *pool = ctx->pool; @@ -319,14 +366,85 @@ static struct file_system_type secretmem_fs = { .kill_sb = kill_anon_super, }; +static int secretmem_reserved_mem_init(void) +{ + struct gen_pool *pool; + struct page *page; + void *addr; + int err; + + if (!secretmem_pool.reserved) + return 0; + + pool = gen_pool_create(PMD_SHIFT, NUMA_NO_NODE); + if (!pool) + return -ENOMEM; + + err = gen_pool_add(pool, (unsigned long)secretmem_pool.reserved, + secretmem_pool.reserved_size, NUMA_NO_NODE); + if (err) + goto err_destroy_pool; + + for (addr = secretmem_pool.reserved; + addr < secretmem_pool.reserved + secretmem_pool.reserved_size; + addr += PAGE_SIZE) { + page = virt_to_page(addr); + __ClearPageReserved(page); + set_page_count(page, 1); + } + + secretmem_pool.pool = pool; + page = virt_to_page(secretmem_pool.reserved); + __kernel_map_pages(page, secretmem_pool.reserved_size / PAGE_SIZE, 0); + return 0; + +err_destroy_pool: + gen_pool_destroy(pool); + return err; +} + static int secretmem_init(void) { - int ret = 0; + int ret; + + ret = secretmem_reserved_mem_init(); + if (ret) + return ret; secretmem_mnt = kern_mount(&secretmem_fs); - if (IS_ERR(secretmem_mnt)) + if (IS_ERR(secretmem_mnt)) { + gen_pool_destroy(secretmem_pool.pool); ret = PTR_ERR(secretmem_mnt); + } return ret; } fs_initcall(secretmem_init); + +static int __init secretmem_setup(char *str) +{ + phys_addr_t align = PMD_SIZE; + unsigned long reserved_size; + void *reserved; + + reserved_size = memparse(str, NULL); + if (!reserved_size) + return 0; + + if (reserved_size * 2 > PUD_SIZE) + align = PUD_SIZE; + + reserved = memblock_alloc(reserved_size, align); + if (!reserved) { + pr_err("failed to reserve %zu bytes\n", secretmem_pool.reserved_size); + return 0; + } + + secretmem_pool.reserved_size = reserved_size; + secretmem_pool.reserved = reserved; + + pr_info("reserved %zuM\n", reserved_size >> 20); + + return 1; +} +__setup("secretmem=", secretmem_setup); -- 2.26.2 _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org 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 X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5906C433E6 for ; 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bh=YvMb+p0jQCDBsVRysCwS/OqQ8tiwgSpqjJbD+ghpSWA=; b=nwa/o5eaesg62xkHm0ZrsK0/m TlScFSAMtiOhXL26+fVXOOrN2vmRHEtDVHoKfNMJTlYqezQwr8L/KfwNhd9VZWZwjYYG6NpN6MWdE dWHNNY574uZY8ItTPiCJpsLbbJMnzcfD0MO2DhSk/ibqlpKxociWVkIbdzNHZUBb+TOvu43svDTUQ cyxMUUPPh6OWMBiZH8ApSQVU9PqZVJghCDFfJBr/+7ngtAncuHEYMeGy8ueNqsBILFBDyZCXYxATO 0xYhtbc0QeA475LtqMF78cyvRQSg8uQpOZ6bsV6Th9h0jb5RjFAIePstdMll/WxDI1hgkIAuQkIb4 Rh+EoWUNw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jxS4N-0007vY-3u; Mon, 20 Jul 2020 09:26:47 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jxS3d-0007ZG-BH; Mon, 20 Jul 2020 09:26:03 +0000 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C6D012176B; Mon, 20 Jul 2020 09:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595237160; bh=xIW2F2IJFqxTzMmaAs6C8+3yiJvBuUFpN7ht+vECA5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rrNLOpGtsBkLwzoA0ZoHKqviCVJ3KJRCdTwu93rSdZ36ELhztooGsQ2e4T8KUYbwf g95kfDYYhWT0rijSXjiKDluNKSd11vd3VHc2VWrEE5zvJz5wMrVk6WVbraWxItZhwN Z/wN2S6aNtjO+InKcFYziVst7pgrShtls+s5WRPo= From: Mike Rapoport To: linux-kernel@vger.kernel.org Subject: [PATCH 6/6] mm: secretmem: add ability to reserve memory at boot Date: Mon, 20 Jul 2020 12:24:35 +0300 Message-Id: <20200720092435.17469-7-rppt@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200720092435.17469-1-rppt@kernel.org> References: <20200720092435.17469-1-rppt@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200720_052601_662732_4A54C5A2 X-CRM114-Status: GOOD ( 24.24 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, "H. Peter Anvin" , Christopher Lameter , Idan Yaniv , Dan Williams , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Arnd Bergmann , James Bottomley , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Andrew Morton , Mike Rapoport Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Mike Rapoport Taking pages out from the direct map and bringing them back may create undesired fragmentation and usage of the smaller pages in the direct mapping of the physical memory. This can be avoided if a significantly large area of the physical memory would be reserved for secretmem purposes at boot time. Add ability to reserve physical memory for secretmem at boot time using "secretmem" kernel parameter and then use that reserved memory as a global pool for secret memory needs. Signed-off-by: Mike Rapoport --- mm/secretmem.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 126 insertions(+), 8 deletions(-) diff --git a/mm/secretmem.c b/mm/secretmem.c index dce56f84968f..322f425dbb22 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -30,6 +31,39 @@ struct secretmem_ctx { unsigned int mode; }; +struct secretmem_pool { + struct gen_pool *pool; + unsigned long reserved_size; + void *reserved; +}; + +static struct secretmem_pool secretmem_pool; + +static struct page *secretmem_alloc_huge_page(gfp_t gfp) +{ + struct gen_pool *pool = secretmem_pool.pool; + unsigned long addr = 0; + struct page *page = NULL; + + if (pool) { + if (gen_pool_avail(pool) < PMD_SIZE) + return NULL; + + addr = gen_pool_alloc(pool, PMD_SIZE); + if (!addr) + return NULL; + + page = virt_to_page(addr); + } else { + page = alloc_pages(gfp, PMD_PAGE_ORDER); + + if (page) + split_page(page, PMD_PAGE_ORDER); + } + + return page; +} + static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER); @@ -38,12 +72,11 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) struct page *page; int err; - page = alloc_pages(gfp, PMD_PAGE_ORDER); + page = secretmem_alloc_huge_page(gfp); if (!page) return -ENOMEM; addr = (unsigned long)page_address(page); - split_page(page, PMD_PAGE_ORDER); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); if (err) { @@ -266,11 +299,13 @@ SYSCALL_DEFINE1(secretmemfd, unsigned long, flags) return err; } -static void secretmem_cleanup_chunk(struct gen_pool *pool, - struct gen_pool_chunk *chunk, void *data) +static void secretmem_recycle_range(unsigned long start, unsigned long end) +{ + gen_pool_free(secretmem_pool.pool, start, PMD_SIZE); +} + +static void secretmem_release_range(unsigned long start, unsigned long end) { - unsigned long start = chunk->start_addr; - unsigned long end = chunk->end_addr; unsigned long nr_pages, addr; nr_pages = (end - start + 1) / PAGE_SIZE; @@ -280,6 +315,18 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, put_page(virt_to_page(addr)); } +static void secretmem_cleanup_chunk(struct gen_pool *pool, + struct gen_pool_chunk *chunk, void *data) +{ + unsigned long start = chunk->start_addr; + unsigned long end = chunk->end_addr; + + if (secretmem_pool.pool) + secretmem_recycle_range(start, end); + else + secretmem_release_range(start, end); +} + static void secretmem_cleanup_pool(struct secretmem_ctx *ctx) { struct gen_pool *pool = ctx->pool; @@ -319,14 +366,85 @@ static struct file_system_type secretmem_fs = { .kill_sb = kill_anon_super, }; +static int secretmem_reserved_mem_init(void) +{ + struct gen_pool *pool; + struct page *page; + void *addr; + int err; + + if (!secretmem_pool.reserved) + return 0; + + pool = gen_pool_create(PMD_SHIFT, NUMA_NO_NODE); + if (!pool) + return -ENOMEM; + + err = gen_pool_add(pool, (unsigned long)secretmem_pool.reserved, + secretmem_pool.reserved_size, NUMA_NO_NODE); + if (err) + goto err_destroy_pool; + + for (addr = secretmem_pool.reserved; + addr < secretmem_pool.reserved + secretmem_pool.reserved_size; + addr += PAGE_SIZE) { + page = virt_to_page(addr); + __ClearPageReserved(page); + set_page_count(page, 1); + } + + secretmem_pool.pool = pool; + page = virt_to_page(secretmem_pool.reserved); + __kernel_map_pages(page, secretmem_pool.reserved_size / PAGE_SIZE, 0); + return 0; + +err_destroy_pool: + gen_pool_destroy(pool); + return err; +} + static int secretmem_init(void) { - int ret = 0; + int ret; + + ret = secretmem_reserved_mem_init(); + if (ret) + return ret; secretmem_mnt = kern_mount(&secretmem_fs); - if (IS_ERR(secretmem_mnt)) + if (IS_ERR(secretmem_mnt)) { + gen_pool_destroy(secretmem_pool.pool); ret = PTR_ERR(secretmem_mnt); + } return ret; } fs_initcall(secretmem_init); + +static int __init secretmem_setup(char *str) +{ + phys_addr_t align = PMD_SIZE; + unsigned long reserved_size; + void *reserved; + + reserved_size = memparse(str, NULL); + if (!reserved_size) + return 0; + + if (reserved_size * 2 > PUD_SIZE) + align = PUD_SIZE; + + reserved = memblock_alloc(reserved_size, align); + if (!reserved) { + pr_err("failed to reserve %zu bytes\n", secretmem_pool.reserved_size); + return 0; + } + + secretmem_pool.reserved_size = reserved_size; + secretmem_pool.reserved = reserved; + + pr_info("reserved %zuM\n", reserved_size >> 20); + + return 1; +} +__setup("secretmem=", secretmem_setup); -- 2.26.2 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3BECCC433E1 for ; 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Mon, 20 Jul 2020 09:26:03 +0000 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C6D012176B; Mon, 20 Jul 2020 09:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595237160; bh=xIW2F2IJFqxTzMmaAs6C8+3yiJvBuUFpN7ht+vECA5A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rrNLOpGtsBkLwzoA0ZoHKqviCVJ3KJRCdTwu93rSdZ36ELhztooGsQ2e4T8KUYbwf g95kfDYYhWT0rijSXjiKDluNKSd11vd3VHc2VWrEE5zvJz5wMrVk6WVbraWxItZhwN Z/wN2S6aNtjO+InKcFYziVst7pgrShtls+s5WRPo= From: Mike Rapoport To: linux-kernel@vger.kernel.org Subject: [PATCH 6/6] mm: secretmem: add ability to reserve memory at boot Date: Mon, 20 Jul 2020 12:24:35 +0300 Message-Id: <20200720092435.17469-7-rppt@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200720092435.17469-1-rppt@kernel.org> References: <20200720092435.17469-1-rppt@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200720_052601_662732_4A54C5A2 X-CRM114-Status: GOOD ( 24.24 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, "H. Peter Anvin" , Christopher Lameter , Idan Yaniv , Dan Williams , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Arnd Bergmann , James Bottomley , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Andrew Morton , Mike Rapoport Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Mike Rapoport Taking pages out from the direct map and bringing them back may create undesired fragmentation and usage of the smaller pages in the direct mapping of the physical memory. This can be avoided if a significantly large area of the physical memory would be reserved for secretmem purposes at boot time. Add ability to reserve physical memory for secretmem at boot time using "secretmem" kernel parameter and then use that reserved memory as a global pool for secret memory needs. Signed-off-by: Mike Rapoport --- mm/secretmem.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 126 insertions(+), 8 deletions(-) diff --git a/mm/secretmem.c b/mm/secretmem.c index dce56f84968f..322f425dbb22 100644 --- a/mm/secretmem.c +++ b/mm/secretmem.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -30,6 +31,39 @@ struct secretmem_ctx { unsigned int mode; }; +struct secretmem_pool { + struct gen_pool *pool; + unsigned long reserved_size; + void *reserved; +}; + +static struct secretmem_pool secretmem_pool; + +static struct page *secretmem_alloc_huge_page(gfp_t gfp) +{ + struct gen_pool *pool = secretmem_pool.pool; + unsigned long addr = 0; + struct page *page = NULL; + + if (pool) { + if (gen_pool_avail(pool) < PMD_SIZE) + return NULL; + + addr = gen_pool_alloc(pool, PMD_SIZE); + if (!addr) + return NULL; + + page = virt_to_page(addr); + } else { + page = alloc_pages(gfp, PMD_PAGE_ORDER); + + if (page) + split_page(page, PMD_PAGE_ORDER); + } + + return page; +} + static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) { unsigned long nr_pages = (1 << PMD_PAGE_ORDER); @@ -38,12 +72,11 @@ static int secretmem_pool_increase(struct secretmem_ctx *ctx, gfp_t gfp) struct page *page; int err; - page = alloc_pages(gfp, PMD_PAGE_ORDER); + page = secretmem_alloc_huge_page(gfp); if (!page) return -ENOMEM; addr = (unsigned long)page_address(page); - split_page(page, PMD_PAGE_ORDER); err = gen_pool_add(pool, addr, PMD_SIZE, NUMA_NO_NODE); if (err) { @@ -266,11 +299,13 @@ SYSCALL_DEFINE1(secretmemfd, unsigned long, flags) return err; } -static void secretmem_cleanup_chunk(struct gen_pool *pool, - struct gen_pool_chunk *chunk, void *data) +static void secretmem_recycle_range(unsigned long start, unsigned long end) +{ + gen_pool_free(secretmem_pool.pool, start, PMD_SIZE); +} + +static void secretmem_release_range(unsigned long start, unsigned long end) { - unsigned long start = chunk->start_addr; - unsigned long end = chunk->end_addr; unsigned long nr_pages, addr; nr_pages = (end - start + 1) / PAGE_SIZE; @@ -280,6 +315,18 @@ static void secretmem_cleanup_chunk(struct gen_pool *pool, put_page(virt_to_page(addr)); } +static void secretmem_cleanup_chunk(struct gen_pool *pool, + struct gen_pool_chunk *chunk, void *data) +{ + unsigned long start = chunk->start_addr; + unsigned long end = chunk->end_addr; + + if (secretmem_pool.pool) + secretmem_recycle_range(start, end); + else + secretmem_release_range(start, end); +} + static void secretmem_cleanup_pool(struct secretmem_ctx *ctx) { struct gen_pool *pool = ctx->pool; @@ -319,14 +366,85 @@ static struct file_system_type secretmem_fs = { .kill_sb = kill_anon_super, }; +static int secretmem_reserved_mem_init(void) +{ + struct gen_pool *pool; + struct page *page; + void *addr; + int err; + + if (!secretmem_pool.reserved) + return 0; + + pool = gen_pool_create(PMD_SHIFT, NUMA_NO_NODE); + if (!pool) + return -ENOMEM; + + err = gen_pool_add(pool, (unsigned long)secretmem_pool.reserved, + secretmem_pool.reserved_size, NUMA_NO_NODE); + if (err) + goto err_destroy_pool; + + for (addr = secretmem_pool.reserved; + addr < secretmem_pool.reserved + secretmem_pool.reserved_size; + addr += PAGE_SIZE) { + page = virt_to_page(addr); + __ClearPageReserved(page); + set_page_count(page, 1); + } + + secretmem_pool.pool = pool; + page = virt_to_page(secretmem_pool.reserved); + __kernel_map_pages(page, secretmem_pool.reserved_size / PAGE_SIZE, 0); + return 0; + +err_destroy_pool: + gen_pool_destroy(pool); + return err; +} + static int secretmem_init(void) { - int ret = 0; + int ret; + + ret = secretmem_reserved_mem_init(); + if (ret) + return ret; secretmem_mnt = kern_mount(&secretmem_fs); - if (IS_ERR(secretmem_mnt)) + if (IS_ERR(secretmem_mnt)) { + gen_pool_destroy(secretmem_pool.pool); ret = PTR_ERR(secretmem_mnt); + } return ret; } fs_initcall(secretmem_init); + +static int __init secretmem_setup(char *str) +{ + phys_addr_t align = PMD_SIZE; + unsigned long reserved_size; + void *reserved; + + reserved_size = memparse(str, NULL); + if (!reserved_size) + return 0; + + if (reserved_size * 2 > PUD_SIZE) + align = PUD_SIZE; + + reserved = memblock_alloc(reserved_size, align); + if (!reserved) { + pr_err("failed to reserve %zu bytes\n", secretmem_pool.reserved_size); + return 0; + } + + secretmem_pool.reserved_size = reserved_size; + secretmem_pool.reserved = reserved; + + pr_info("reserved %zuM\n", reserved_size >> 20); + + return 1; +} +__setup("secretmem=", secretmem_setup); -- 2.26.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel