From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Thu, 13 Oct 2022 12:38:23 +0200 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1oivbc-007G5T-OY for lore@lore.pengutronix.de; Thu, 13 Oct 2022 12:38:23 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oivba-0006wm-Lm for lore@pengutronix.de; Thu, 13 Oct 2022 12:38:23 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=bJfY8+rAuIwySo2wjujl9NHl0vn0sATE8Q/S3pummaI=; b=EmR2FvpLU192bGjmHCa1nZHZHO QrscG3EVMq/xjASdhhsxN76mxY84ErCcTVJN3TgYSGgNsigEdVUSInzofjCPdGSh5TJyLqzDdvU+y u+tcnS7mZv1MtKVepE5dAHzYudAU5Mgceodj0UsXqfcwPpPHeQsjcLkON+nxM8OovOtOtX3vK3jGJ Tv7uwW39JXvRb9tmHTaxxnS8EoBzjxCvGyPbDUrXMKcq9loION+novUBZF+juIHsZhTA6HlN2nEPf +YvJbqYsqMyZD2m7XPpPjeURf71fxqGR2t9tY3xHdohokzRLv4PwvH/KKolrICBG5wq8Y0DYQ7ayF jagQERnA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oivZq-00BQwj-VS; Thu, 13 Oct 2022 10:36:35 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oivZl-00BQve-Ro for barebox@lists.infradead.org; Thu, 13 Oct 2022 10:36:31 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1oivZi-0006qw-Bg for barebox@lists.infradead.org; Thu, 13 Oct 2022 12:36:26 +0200 Message-ID: <5646a232-b4f7-75c9-31ba-128c49ba73ff@pengutronix.de> Date: Thu, 13 Oct 2022 12:36:26 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Content-Language: en-US To: "barebox@lists.infradead.org" References: <20221013090352.562170-1-a.fatoum@pengutronix.de> <20221013090352.562170-4-a.fatoum@pengutronix.de> From: Ahmad Fatoum In-Reply-To: <20221013090352.562170-4-a.fatoum@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221013_033629_926392_A14D16A6 X-CRM114-Status: GOOD ( 21.95 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.2 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH master 3/3] RISC-V: add compiler barriers around unrelocated accesses X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) On 13.10.22 11:03, Ahmad Fatoum wrote: > We observed on ARM miscompilation because get_runtime_offset() was > cached before relocation, while address computation of symbol happened > after, effectively adding the base address twice to the symbol offset. > > New get_unrelocated() hides origin of the symbol going into the address > calculation and thereby thwarts this optimization. Employ it in RISC-V > code as well to avoid such issues as experienced on ARM. > > Signed-off-by: Ahmad Fatoum > --- > arch/riscv/boot/uncompress.c | 4 ++-- > arch/riscv/include/asm/sections.h | 2 +- > arch/riscv/lib/reloc.c | 6 +++--- > 3 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/arch/riscv/boot/uncompress.c b/arch/riscv/boot/uncompress.c > index ee24f81e0159..eab51c8d52bc 100644 > --- a/arch/riscv/boot/uncompress.c > +++ b/arch/riscv/boot/uncompress.c > @@ -36,8 +36,8 @@ void __noreturn barebox_pbl_start(unsigned long membase, unsigned long memsize, > irq_init_vector(riscv_mode()); > > /* piggy data is not relocated, so determine the bounds now */ > - pg_start = input_data + get_runtime_offset(); > - pg_end = input_data_end + get_runtime_offset(); > + pg_start = get_unrelocated(input_data); > + pg_end = get_unrelocated(input_data_end); > pg_len = pg_end - pg_start; > uncompressed_len = input_data_len(); > > diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h > index 6673648bcd58..b90f4d6d2ad5 100644 > --- a/arch/riscv/include/asm/sections.h > +++ b/arch/riscv/include/asm/sections.h > @@ -19,7 +19,7 @@ unsigned long get_runtime_offset(void); > > static inline unsigned int input_data_len(void) > { > - return get_unaligned((const u32 *)(input_data_end + get_runtime_offset() - 4)); > + return get_unaligned((const u32 *)get_unrelocated(input_data_end) - 1); > } > > #endif > diff --git a/arch/riscv/lib/reloc.c b/arch/riscv/lib/reloc.c > index 13118a9ac54f..1dddf627d0b9 100644 > --- a/arch/riscv/lib/reloc.c > +++ b/arch/riscv/lib/reloc.c > @@ -42,9 +42,9 @@ void relocate_to_current_adr(void) > if (!offset) > return; > > - dstart = __rel_dyn_start + offset; > - dend = __rel_dyn_end + offset; > - dynsym = (void *)__dynsym_start + offset; > + dstart = get_unrelocated(__rel_dyn_start); > + dend = get_unrelocated(__rel_dyn_end); > + dynsym = get_unrelocated(__dynsym_start) + offset; Ouch, + offset shouldn't be here. Will fix for v2. > > for (rela = dstart; (void *)rela < dend; rela++) { > unsigned long *fixup; -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |