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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1435C77B73 for ; Tue, 30 May 2023 14:33:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232623AbjE3Odz (ORCPT ); Tue, 30 May 2023 10:33:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231177AbjE3Odx (ORCPT ); Tue, 30 May 2023 10:33:53 -0400 Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [217.70.183.193]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 684888F for ; Tue, 30 May 2023 07:33:50 -0700 (PDT) X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr X-GND-Sasl: alex@ghiti.fr Received: by mail.gandi.net (Postfix) with ESMTPSA id 67A73240007; Tue, 30 May 2023 14:33:45 +0000 (UTC) Message-ID: <92d4aaa8-a1ed-74e1-3a22-df9be1ca1e4a@ghiti.fr> Date: Tue, 30 May 2023 16:33:45 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH -fixes] riscv: Fix relocatable kernels with early alternatives using -fno-pie Content-Language: en-US To: Conor Dooley Cc: Conor Dooley , Alexandre Ghiti , Paul Walmsley , Palmer Dabbelt , Albert Ou , Andreas Schwab , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org References: <20230526-rockfish-moody-f6d3e71f9d24@spud> <20230527-hyperlink-doctrine-ef22cfcb508a@spud> <20230528-darkness-grandly-6cb9e014391d@spud> <20230528-uneatable-earpiece-3f8673548863@spud> <20230529-skillet-quarters-3fbc3b6edb3a@spud> <41e57bb9-ce0c-7772-abeb-5c01d5ec19bb@ghiti.fr> <20230530-polka-trifle-7ccd7a093099@wendy> From: Alexandre Ghiti In-Reply-To: <20230530-polka-trifle-7ccd7a093099@wendy> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/05/2023 13:27, Conor Dooley wrote: > On Mon, May 29, 2023 at 09:37:28PM +0200, Alexandre Ghiti wrote: >> On 29/05/2023 21:06, Conor Dooley wrote: >>> On Mon, May 29, 2023 at 08:51:57PM +0200, Alexandre Ghiti wrote: >>>> On 28/05/2023 15:56, Conor Dooley wrote: >>>>> On Sun, May 28, 2023 at 03:42:59PM +0200, Alexandre Ghiti wrote: >>>>>> Hmmm, it still works for me with both clang and gcc-9. >>>>> gcc-9 is a bit of a relic, do you have more recent compilers lying >>>>> around? If not, I can try some older compilers at some point. >>>>> >>>>>> You don't have to do that now but is there a way I could get your compiled >>>>>> image? With the sha1 used to build it? Sorry, I don't see what happens, I >>>>>> need to get my hands dirty in some debug! >>>>> What do you mean by "sha1"? It falls with v6.4-rc1 which is a stable >>>>> hash, if that's what you're looking for. >>>>> >>>>> Otherwise, >>>>> https://github.com/ConchuOD/riscv-env/releases/download/v2022.03/vmlinux.bin >>>>> (ignore the release crap haha, too lazy to find a proper hosting >>>>> mechanism) >>>> Ok, I don't get much info without the symbols, can you also provide the >>>> vmlinux please? But at least your image does not boot, not during the early >>>> boot though because the mmu is enabled. >>> Do you see anything print when you try it? Cos I do not. Iff I have time >>> tomorrow, I'll go poking with gdb. I'm sorry I have not really done any >>> investigating, I have been really busy this last week or so with >>> dt-binding stuff but I should be freer again from tomorrow. >>> >>> https://github.com/ConchuOD/riscv-env/releases/download/v2022.03/vmlinux >> >> Better, the trap happens in kasan_early_init() when it tries to access a >> global symbol using the GOT but ends up with a NULL pointer, which is weird. >> So to me, this is not related to kasan, it happens that kasan_early_init() >> is the first function called after enabling the mmu, I think you may have an >> issue with the filling of the relocations. > Yeah, it reproduces without KASAN. > >> Sorry to bother you again, but if >> at some point you can recompile with DEBUG_INFO enabled, that would be >> perfect! And also provide the vmlinux.relocs file. Sorry for all that, too >> bad I can't reproduce it. > New vmlinux & vmlinux.relocs here: > https://microchiptechnology-my.sharepoint.com/:u:/g/personal/conor_dooley_microchip_com/EZpFNxYYrnNAh5Z3c-rf0pUBBpdPGTLafqdtfcXRUUBkXw?e=7KKMHX > They're pretty massive unfortunately & hopefully that is not some > garbage internal-only link. > .config is a wee bit different, cos different build machine, but the > problem still manifests on a icicle. I've added it to the tarball just > in case. Ok so I had to recreate the Image from the files you gave me and it boots fine using qemu: is that expected? Because you only mention the icicle above. [    0.000000] Linux version 6.4.0-rc1 (conor@wendy) (ClangBuiltLinux clang version 15.0.7 (/home/conor/stuff/dev/llvm/clang 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a), ClangBuiltLinux LLD 15.0.7) #1 SMP PREEMPT Tue May 30 12:13:12 IST 2023 [    0.000000] random: crng init done [    0.000000] Machine model: riscv-virtio,qemu [    0.000000] earlycon: ns16550a0 at MMIO 0x0000000010000000 (options '') [    0.000000] printk: bootconsole [ns16550a0] enabled [    0.000000] printk: debug: skip boot console de-registration. [    0.000000] efi: UEFI not found. [    0.000000] OF: reserved mem: 0x0000000080000000..0x000000008003ffff (256 KiB) map non-reusable mmode_resv0@80000000 [    0.000000] Zone ranges: [    0.000000]   DMA32    [mem 0x0000000080000000-0x00000000ffffffff] [    0.000000]   Normal   [mem 0x0000000100000000-0x000000017fffffff] [    0.000000] Movable zone start for each node [    0.000000] Early memory node ranges [    0.000000]   node   0: [mem 0x0000000080000000-0x000000017fffffff] [    0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x000000017fffffff] [    0.000000] SBI specification v1.0 detected [    0.000000] SBI implementation ID=0x1 Version=0x10002 [    0.000000] SBI TIME extension detected [    0.000000] SBI IPI extension detected [    0.000000] SBI RFENCE extension detected [    0.000000] SBI SRST extension detected [    0.000000] SBI HSM extension detected [    0.000000] riscv: base ISA extensions acdfhim [    0.000000] riscv: ELF capabilities acdfim [    0.000000] percpu: Embedded 30 pages/cpu s83872 r8192 d30816 u122880 [    0.000000] Kernel command line: earlycon keep_bootcon root=/dev/mmcblk1p2 rootdelay=10 reboot=cold [    0.000000] Dentry cache hash table entries: 524288 (order: 10, 4194304 bytes, linear) [    0.000000] Inode-cache hash table entries: 262144 (order: 9, 2097152 bytes, linear) [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 1034240 [    0.000000] mem auto-init: stack:all(zero), heap alloc:off, heap free:off ... >>>> I tried with gcc-12 and it still works fine on my end, so frustrating! >>> Crap! Also, should you not be enjoying a public holiday rather than >>> debugging?! Or maybe debugging is enjoyable for you... >> >> Ahah, this is what I enjoy doing when the kids finally sleep :) >> >> >> Thank you again for your very quick feedback, really appreciated! > No worries. > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv