From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752896AbeDPWsO (ORCPT ); Mon, 16 Apr 2018 18:48:14 -0400 Received: from foss.arm.com ([217.140.101.70]:37044 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750972AbeDPWsN (ORCPT ); Mon, 16 Apr 2018 18:48:13 -0400 Date: Mon, 16 Apr 2018 17:48:11 -0500 From: Kim Phillips To: Namhyung Kim Cc: Arnaldo Carvalho de Melo , Jiri Olsa , Ingo Molnar , Peter Zijlstra , Jiri Olsa , LKML , Subject: Re: [PATCH] perf tools: set kernel end address properly Message-Id: <20180416174811.1aca9106364effe435f363c8@arm.com> In-Reply-To: <20180416122407.0d90863b69fed80166384850@arm.com> References: <20180416042240.21528-1-namhyung@kernel.org> <20180416092345.GA23274@krava> <20180416135125.GA23802@kernel.org> <20180416110730.1dd12801e43be66ea5d0cc48@arm.com> <20180416165800.GD3202@kernel.org> <20180416122407.0d90863b69fed80166384850@arm.com> Organization: Arm X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 16 Apr 2018 12:24:07 -0500 Kim Phillips wrote: > On Mon, 16 Apr 2018 13:58:00 -0300 > Arnaldo Carvalho de Melo wrote: > > > Em Mon, Apr 16, 2018 at 11:07:30AM -0500, Kim Phillips escreveu: > > > On Mon, 16 Apr 2018 10:51:25 -0300 > > > Arnaldo Carvalho de Melo wrote: > > > > > > > Em Mon, Apr 16, 2018 at 11:23:45AM +0200, Jiri Olsa escreveu: > > > > > On Mon, Apr 16, 2018 at 01:22:40PM +0900, Namhyung Kim wrote: > > > > > > The map_groups__fixup_end() was called to set end addresses of kernel > > > > > > map and module maps. But now machine__create_modules() is set the end > > > > > > address of modules properly so the only remaining piece is the kernel > > > > > > map. We can set it with adjacent module's address directly instead of > > > > > > calling the map_groups__fixup_end(). If there's no module after the > > > > > > kernel map, the end address will be ~0ULL. > > > > > > > > I wonder if it wouldn't be better to have it as last symbol + PAGE_SIZE > > > > or something like that... > > > > > > > > But, anyway, Kim, does this fix things for you? Can I have your > > > > Tested-by? > > > > > > No, perf test 1 still fails: > > > > > > vmlinux symtab matches kallsyms: FAILED! > > > > Ok, -vv please > > a perf/urgent from last week (commit 918965d4897) + this patch: > > $ sudo ./perf test -vv 1 |& head > 1: vmlinux symtab matches kallsyms : > --- start --- > test child forked, pid 6194 > Looking at the vmlinux_path (8 entries long) > Using /lib/modules/4.16.0+/build/vmlinux for symbols > ERR : 0xffff200008081000: do_undefinstr not on kallsyms > ERR : 0xffff2000080810b8: do_sysinstr not on kallsyms > ERR : 0xffff200008081258: do_debug_exception not on kallsyms > ERR : 0xffff200008081648: do_mem_abort not on kallsyms > ERR : 0xffff2000080818b8: do_el0_irq_bp_hardening not on kallsyms > $ sudo ./perf test -vv 1 |& tail > ERR : 0xffff20000a1d37c8: tramp_exit_native not on kallsyms > ERR : 0xffff20000a1d37e8: tramp_exit_compat not on kallsyms > ERR : 0xffff20000a1d4000: __entry_tramp_text_end not on kallsyms > WARN: Maps only in vmlinux: > ffff200008080000-ffff200008081000 10000 [kernel].head.text > ffff20000aec0000-ffff20000aff7548 2e50000 [kernel].init.text > ffff20000aff7548-ffff20000b0126d4 2f87548 [kernel].exit.text > test child finished with -1 > ---- end ---- > vmlinux symtab matches kallsyms: FAILED! this patch's advertised "If there's no module after the kernel map, the end address will be ~0ULL." doesn't seem to be working: the value it gets for 'end' is 0xffff200008080000. I even hardcoded 'end' variable to the value for '_end' in kallsyms prior to the machine__set_kernel_mmap() call, and test 1 still fails. The problem is earlier on in the code, somewhere. I've moved to working on the updated perf/urgent. Reverting the original patch doesn't make test 1 resume succeeding anymore. Pointers appreciated. Kim