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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D68C0C18E5B for ; Mon, 16 Mar 2020 02:40:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC1EA206E9 for ; Mon, 16 Mar 2020 02:40:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584326446; bh=uqsP2dN8vW/yN9dmAvxrzeEo6UosA6daNFnTZ48jmfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UQQZ9s9WAYQOIcwUiIlP6Wn1Ce3pHGp+0ojzDDmRJR/hXfeyTmV/y1dQGNpqwn6qt R+sYqdczbIxCq949lUwYNGkn2HtzJ31WPtRVB0UwAtC8zq7ZlvOhMSteEL7eIsbcQX UJjmyvaeCDL/ugMogDvvZl2JEBA4o+b5aUnC50lI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729954AbgCPCkp (ORCPT ); Sun, 15 Mar 2020 22:40:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:36878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729668AbgCPCdx (ORCPT ); Sun, 15 Mar 2020 22:33:53 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 97ECB20737; Mon, 16 Mar 2020 02:33:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584326033; bh=uqsP2dN8vW/yN9dmAvxrzeEo6UosA6daNFnTZ48jmfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vs4QkR/WUQBMtN13FRaqmXV+gfLLp2LItdjqcaTrvgRVLRjfdz4OuB305wtPeA/c+ ujbsk4DZN37maJYAxVhUv4gX0DdrcLZ17/V+PbqKptF2Bi2i4Md4V5kj5eU78ZRwZq 8wXW3RVUGthdGIBZ8tiEmNoOjPLNcxPi4b5Vcjy8= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vincent Chen , Alexandre Ghiti , Anup Patel , Carlos de Paula , Palmer Dabbelt , Sasha Levin , linux-riscv@lists.infradead.org Subject: [PATCH AUTOSEL 5.5 28/41] riscv: avoid the PIC offset of static percpu data in module beyond 2G limits Date: Sun, 15 Mar 2020 22:33:06 -0400 Message-Id: <20200316023319.749-28-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200316023319.749-1-sashal@kernel.org> References: <20200316023319.749-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vincent Chen [ Upstream commit 0cff8bff7af886af0923d5c91776cd51603e531f ] The compiler uses the PIC-relative method to access static variables instead of GOT when the code model is PIC. Therefore, the limitation of the access range from the instruction to the symbol address is +-2GB. Under this circumstance, the kernel cannot load a kernel module if this module has static per-CPU symbols declared by DEFINE_PER_CPU(). The reason is that kernel relocates the .data..percpu section of the kernel module to the end of kernel's .data..percpu. Hence, the distance between the per-CPU symbols and the instruction will exceed the 2GB limits. To solve this problem, the kernel should place the loaded module in the memory area [&_end-2G, VMALLOC_END]. Signed-off-by: Vincent Chen Suggested-by: Alexandre Ghiti Suggested-by: Anup Patel Tested-by: Alexandre Ghiti Tested-by: Carlos de Paula Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin --- arch/riscv/kernel/module.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c index b7401858d872f..8bbe5dbe1341b 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -8,6 +8,10 @@ #include #include #include +#include +#include +#include +#include static int apply_r_riscv_32_rela(struct module *me, u32 *location, Elf_Addr v) { @@ -386,3 +390,15 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, return 0; } + +#if defined(CONFIG_MMU) && defined(CONFIG_64BIT) +#define VMALLOC_MODULE_START \ + max(PFN_ALIGN((unsigned long)&_end - SZ_2G), VMALLOC_START) +void *module_alloc(unsigned long size) +{ + return __vmalloc_node_range(size, 1, VMALLOC_MODULE_START, + VMALLOC_END, GFP_KERNEL, + PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, + __builtin_return_address(0)); +} +#endif -- 2.20.1