From owner-svn-src-head@freebsd.org Wed Feb 5 11:34:11 2020 Return-Path: Delivered-To: svn-src-head@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 7F3C5248142; Wed, 5 Feb 2020 11:34:11 +0000 (UTC) (envelope-from luporl@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48CKGC2c25z4RNq; Wed, 5 Feb 2020 11:34:11 +0000 (UTC) (envelope-from luporl@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 54B1B1F5A; Wed, 5 Feb 2020 11:34:11 +0000 (UTC) (envelope-from luporl@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 015BYBUE050389; Wed, 5 Feb 2020 11:34:11 GMT (envelope-from luporl@FreeBSD.org) Received: (from luporl@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 015BYBq4050388; Wed, 5 Feb 2020 11:34:11 GMT (envelope-from luporl@FreeBSD.org) Message-Id: <202002051134.015BYBq4050388@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: luporl set sender to luporl@FreeBSD.org using -f From: Leandro Lupori Date: Wed, 5 Feb 2020 11:34:11 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r357570 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: luporl X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 357570 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Feb 2020 11:34:11 -0000 Author: luporl Date: Wed Feb 5 11:34:10 2020 New Revision: 357570 URL: https://svnweb.freebsd.org/changeset/base/357570 Log: Add SYSCTL to get KERNBASE and relocated KERNBASE This change adds 2 new SYSCTLs, to retrieve the original and relocated KERNBASE values. This provides an easy, architecture independent way to calculate the running kernel displacement (current/load address minus original base address). The initial goal for this change is to add a new libkvm function that returns the kernel displacement, both for live kernels and crashdumps. This would in turn be used by kgdb to find out how to relocate kernel symbols (if needed). Reviewed by: jhb Differential Revision: https://reviews.freebsd.org/D23284 Modified: head/sys/kern/link_elf.c Modified: head/sys/kern/link_elf.c ============================================================================== --- head/sys/kern/link_elf.c Wed Feb 5 11:02:00 2020 (r357569) +++ head/sys/kern/link_elf.c Wed Feb 5 11:34:10 2020 (r357570) @@ -51,6 +51,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include @@ -389,6 +390,13 @@ link_elf_link_common_finish(linker_file_t lf) extern vm_offset_t __startkernel, __endkernel; +static unsigned long kern_relbase = KERNBASE; + +SYSCTL_ULONG(_kern, OID_AUTO, base_address, CTLFLAG_RD, + SYSCTL_NULL_ULONG_PTR, KERNBASE, "Kernel base address"); +SYSCTL_ULONG(_kern, OID_AUTO, relbase_address, CTLFLAG_RD, + &kern_relbase, 0, "Kernel relocated base address"); + static void link_elf_init(void* arg) { @@ -431,6 +439,7 @@ link_elf_init(void* arg) #ifdef __powerpc__ linker_kernel_file->address = (caddr_t)__startkernel; linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel); + kern_relbase = (unsigned long)__startkernel; #else linker_kernel_file->address += KERNBASE; linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;