From patchwork Fri Nov 8 12:24:04 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Martin X-Patchwork-Id: 3157951 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E5B51BEEB2 for ; Fri, 8 Nov 2013 12:25:16 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4A56C20483 for ; Fri, 8 Nov 2013 12:25:12 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A28CD2047D for ; Fri, 8 Nov 2013 12:25:10 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vel7T-0005jM-4X; Fri, 08 Nov 2013 12:24:59 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vel7Q-0002ac-Jh; Fri, 08 Nov 2013 12:24:56 +0000 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21] helo=cam-smtp0.cambridge.arm.com) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vel7N-0002Zt-Uf for linux-arm-kernel@lists.infradead.org; Fri, 08 Nov 2013 12:24:54 +0000 Received: from e103592.cambridge.arm.com (e103592.cambridge.arm.com [10.1.203.45]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with ESMTP id rA8CONPT008019; Fri, 8 Nov 2013 12:24:23 GMT From: Dave Martin To: Will Deacon Subject: [PATCH v2] ARM: kexec: Use the right ISA for relocate_new_kernel Date: Fri, 8 Nov 2013 12:24:04 +0000 Message-Id: <1383913444-9153-1-git-send-email-Dave.Martin@arm.com> X-Mailer: git-send-email 1.7.9.5 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131108_072454_304152_92635984 X-CRM114-Status: GOOD ( 12.04 ) X-Spam-Score: -2.6 (--) Cc: Taras Kondratiuk , linaro-kernel@lists.linaro.org, Dave Martin , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Copying a function with memcpy() and then trying to execute the result isn't trivially portable to Thumb. This patch modifies the kexec soft restart code to copy its assembler trampoline relocate_new_kernel() using fncpy() instead, so that relocate_new_kernel can be in the same ISA as the rest of the kernel without problems. Signed-off-by: Dave Martin --- Changes since v1: * Move ENDPROC() after relocate_new_kernel's literals, to be consistent the location of relocate_new_kernel_end and with the way GCC sets ELF symbol sizes for functions. This is just a tidyup, with no functional impact. arch/arm/kernel/machine_kexec.c | 17 ++++++++++------- arch/arm/kernel/relocate_kernel.S | 8 ++++++-- 2 files changed, 16 insertions(+), 9 deletions(-) diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index 57221e3..f0d180d 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -14,11 +14,12 @@ #include #include #include +#include #include #include #include -extern const unsigned char relocate_new_kernel[]; +extern void relocate_new_kernel(void); extern const unsigned int relocate_new_kernel_size; extern unsigned long kexec_start_address; @@ -142,6 +143,8 @@ void machine_kexec(struct kimage *image) { unsigned long page_list; unsigned long reboot_code_buffer_phys; + unsigned long reboot_entry = (unsigned long)relocate_new_kernel; + unsigned long reboot_entry_phys; void *reboot_code_buffer; /* @@ -168,16 +171,16 @@ void machine_kexec(struct kimage *image) /* copy our kernel relocation code to the control code page */ - memcpy(reboot_code_buffer, - relocate_new_kernel, relocate_new_kernel_size); + reboot_entry = fncpy(reboot_code_buffer, + reboot_entry, + relocate_new_kernel_size); + reboot_entry_phys = (unsigned long)reboot_entry + + (reboot_code_buffer_phys - (unsigned long)reboot_code_buffer); - - flush_icache_range((unsigned long) reboot_code_buffer, - (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE); printk(KERN_INFO "Bye!\n"); if (kexec_reinit) kexec_reinit(); - soft_restart(reboot_code_buffer_phys); + soft_restart(reboot_entry_phys); } diff --git a/arch/arm/kernel/relocate_kernel.S b/arch/arm/kernel/relocate_kernel.S index d0cdedf..9585896 100644 --- a/arch/arm/kernel/relocate_kernel.S +++ b/arch/arm/kernel/relocate_kernel.S @@ -2,10 +2,12 @@ * relocate_kernel.S - put the kernel image in place to boot */ +#include #include - .globl relocate_new_kernel -relocate_new_kernel: + .align 3 /* not needed for this code, but keeps fncpy() happy */ + +ENTRY(relocate_new_kernel) ldr r0,kexec_indirection_page ldr r1,kexec_start_address @@ -79,6 +81,8 @@ kexec_mach_type: kexec_boot_atags: .long 0x0 +ENDPROC(relocate_new_kernel) + relocate_new_kernel_end: .globl relocate_new_kernel_size