From patchwork Mon Nov 28 19:02:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 13057884 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 4A4F8C4332F for ; Mon, 28 Nov 2022 19:03:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B09596B0075; Mon, 28 Nov 2022 14:03:16 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id ABAD66B0078; Mon, 28 Nov 2022 14:03:16 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9823F6B007B; Mon, 28 Nov 2022 14:03:16 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 88F4B6B0075 for ; Mon, 28 Nov 2022 14:03:16 -0500 (EST) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 506EB808C6 for ; Mon, 28 Nov 2022 19:03:16 +0000 (UTC) X-FDA: 80183773992.04.EF95AF3 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by imf04.hostedemail.com (Postfix) with ESMTP id 8D01A4000A for ; Mon, 28 Nov 2022 19:03:15 +0000 (UTC) Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2ASI1AK7014113 for ; Mon, 28 Nov 2022 11:03:14 -0800 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3m3hcvgu4y-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 28 Nov 2022 11:03:14 -0800 Received: from twshared15216.17.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 28 Nov 2022 11:03:11 -0800 Received: by devbig932.frc1.facebook.com (Postfix, from userid 4523) id 5F2BE10980404; Mon, 28 Nov 2022 11:03:05 -0800 (PST) From: Song Liu To: , CC: , , , , , , , Song Liu Subject: [PATCH bpf-next v5 6/6] x86: use register_text_tail_vm Date: Mon, 28 Nov 2022 11:02:45 -0800 Message-ID: <20221128190245.2337461-7-song@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221128190245.2337461-1-song@kernel.org> References: <20221128190245.2337461-1-song@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: g2w2uoXw8jlRHFWNU2p4uzWuGU1ixCgm X-Proofpoint-ORIG-GUID: g2w2uoXw8jlRHFWNU2p4uzWuGU1ixCgm X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-11-28_17,2022-11-28_02,2022-06-22_01 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1669662195; a=rsa-sha256; cv=none; b=TJ9i8EL1kraouczTIGK9fl6wqM6iKFNZcE4ixIUmTcPC0f3tsU6/DA5OL0NhKYJX80QHb+ 9s0YgVQShRsYbVF4hl7SETJ8ZEfBKS3hOnWzcSikjj57vo5IdbWExsGvB5z3+93YL8uywf yKXkwpsUe+ACTclVOirHH4HDRJ2Rd+A= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=kernel.org (policy=none); spf=pass (imf04.hostedemail.com: domain of "prvs=3331966363=songliubraving@meta.com" designates 67.231.145.42 as permitted sender) smtp.mailfrom="prvs=3331966363=songliubraving@meta.com" ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1669662195; 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=9EFJ58r9sBaqUXDYF0WOWP9QVaoJCj4kNjNSNp44LzQ=; b=gCxm1Zw3KGjjThTs8rv1cf4gArfXPvgDIeEob75HbH7FyVA7zAX/pFbH4DdEAh5jK/LV9i z9NEUjcPU/WWX1g2exqNgV0N966dr50GeMuNkpjVl6CHc654BiGsMdW63alBZth+pIAhgn ymTNpM3KFk4IGJllhhw59Hys67m0dYg= X-Stat-Signature: mon4iwqif3sh5y754nm1y7cqxt5ang4u X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 8D01A4000A Authentication-Results: imf04.hostedemail.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=kernel.org (policy=none); spf=pass (imf04.hostedemail.com: domain of "prvs=3331966363=songliubraving@meta.com" designates 67.231.145.42 as permitted sender) smtp.mailfrom="prvs=3331966363=songliubraving@meta.com" X-Rspam-User: X-HE-Tag: 1669662195-762329 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: Allocate 2MB pages up to round_up(_etext, 2MB), and register memory [round_up(_etext, 4kb), round_up(_etext, 2MB)] with register_text_tail_vm so that we can use this part of memory for dynamic kernel text (BPF programs, etc.). Here is an example: [root@eth50-1 ~]# grep _etext /proc/kallsyms ffffffff82202a08 T _etext [root@eth50-1 ~]# grep bpf_prog_ /proc/kallsyms | tail -n 3 ffffffff8220f920 t bpf_prog_cc61a5364ac11d93_handle__sched_wakeup [bpf] ffffffff8220fa28 t bpf_prog_cc61a5364ac11d93_handle__sched_wakeup_new [bpf] ffffffff8220fad4 t bpf_prog_3bf73fa16f5e3d92_handle__sched_switch [bpf] [root@eth50-1 ~]# grep 0xffffffff82200000 /sys/kernel/debug/page_tables/kernel 0xffffffff82200000-0xffffffff82400000 2M ro PSE x pmd ffffffff82200000-ffffffff82400000 is a 2MB page, serving kernel text, and bpf programs. Also update Documentation/x86/x86_64/mm.rst to show execmem can be mapped to kernel text addresses. Signed-off-by: Song Liu --- Documentation/x86/x86_64/mm.rst | 4 ++-- arch/x86/include/asm/pgtable_64_types.h | 1 + arch/x86/mm/init_64.c | 4 +++- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/Documentation/x86/x86_64/mm.rst b/Documentation/x86/x86_64/mm.rst index 9798676bb0bf..6ee95e5fa7e9 100644 --- a/Documentation/x86/x86_64/mm.rst +++ b/Documentation/x86/x86_64/mm.rst @@ -62,7 +62,7 @@ Complete virtual memory map with 4-level page tables ffffff8000000000 | -512 GB | ffffffeeffffffff | 444 GB | ... unused hole ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | ... unused hole - ffffffff80000000 | -2 GB | ffffffff9fffffff | 512 MB | kernel text mapping, mapped to physical address 0 + ffffffff80000000 | -2 GB | ffffffff9fffffff | 512 MB | kernel text mapping and execmem, mapped to physical address 0 ffffffff80000000 |-2048 MB | | | ffffffffa0000000 |-1536 MB | fffffffffeffffff | 1520 MB | module mapping space ffffffffff000000 | -16 MB | | | @@ -121,7 +121,7 @@ Complete virtual memory map with 5-level page tables ffffff8000000000 | -512 GB | ffffffeeffffffff | 444 GB | ... unused hole ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | ... unused hole - ffffffff80000000 | -2 GB | ffffffff9fffffff | 512 MB | kernel text mapping, mapped to physical address 0 + ffffffff80000000 | -2 GB | ffffffff9fffffff | 512 MB | kernel text mapping and execmem, mapped to physical address 0 ffffffff80000000 |-2048 MB | | | ffffffffa0000000 |-1536 MB | fffffffffeffffff | 1520 MB | module mapping space ffffffffff000000 | -16 MB | | | diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 04f36063ad54..c0f9cceb109a 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -101,6 +101,7 @@ extern unsigned int ptrs_per_p4d; #define PUD_MASK (~(PUD_SIZE - 1)) #define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE - 1)) +#define PMD_ALIGN(x) (((unsigned long)(x) + (PMD_SIZE - 1)) & PMD_MASK) /* * See Documentation/x86/x86_64/mm.rst for a description of the memory map. diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 3f040c6e5d13..5b42fc0c6099 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1373,7 +1373,7 @@ void mark_rodata_ro(void) unsigned long start = PFN_ALIGN(_text); unsigned long rodata_start = PFN_ALIGN(__start_rodata); unsigned long end = (unsigned long)__end_rodata_hpage_align; - unsigned long text_end = PFN_ALIGN(_etext); + unsigned long text_end = PMD_ALIGN(_etext); unsigned long rodata_end = PFN_ALIGN(__end_rodata); unsigned long all_end; @@ -1414,6 +1414,8 @@ void mark_rodata_ro(void) (void *)rodata_end, (void *)_sdata); debug_checkwx(); + register_text_tail_vm(PFN_ALIGN((unsigned long)_etext), + PMD_ALIGN((unsigned long)_etext)); } int kern_addr_valid(unsigned long addr)