From patchwork Thu May 2 01:53:30 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Konrad Rzeszutek Wilk X-Patchwork-Id: 2509841 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id CE1F6DF230 for ; Thu, 2 May 2013 01:53:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757564Ab3EBBx5 (ORCPT ); Wed, 1 May 2013 21:53:57 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:31586 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757115Ab3EBBx4 (ORCPT ); Wed, 1 May 2013 21:53:56 -0400 Received: from acsinet21.oracle.com (acsinet21.oracle.com [141.146.126.237]) by aserp1040.oracle.com (Sentrion-MTA-4.3.1/Sentrion-MTA-4.3.1) with ESMTP id r421rba2007171 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 2 May 2013 01:53:38 GMT Received: from aserz7021.oracle.com (aserz7021.oracle.com [141.146.126.230]) by acsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id r421raqT009411 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Thu, 2 May 2013 01:53:37 GMT Received: from abhmt118.oracle.com (abhmt118.oracle.com [141.146.116.70]) by aserz7021.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id r421ral1009402; Thu, 2 May 2013 01:53:36 GMT Received: from phenom.dumpdata.com (/50.195.21.189) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 01 May 2013 18:53:36 -0700 Received: by phenom.dumpdata.com (Postfix, from userid 1000) id A1A5D1BF7D6; Wed, 1 May 2013 21:53:34 -0400 (EDT) From: Konrad Rzeszutek Wilk To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rjw@sisk.pl, pavel@ucw.cz, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org Cc: Konrad Rzeszutek Wilk Subject: [PATCH] x86, x86-64, gdt, hibernate: Store/load GDT for hibernate path. Date: Wed, 1 May 2013 21:53:30 -0400 Message-Id: <1367459610-9656-2-git-send-email-konrad.wilk@oracle.com> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1367459610-9656-1-git-send-email-konrad.wilk@oracle.com> References: <1367459610-9656-1-git-send-email-konrad.wilk@oracle.com> X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The git commite7a5cd063c7b4c58417f674821d63f5eb6747e37 ("x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path is not needed.") assumes that for the hibernate path the booting kernel and the resuming kernel MUST be the same. That is certainly the case for a 32-bit kernel (see check_image_kernel and CONFIG_ARCH_HIBERNATION_HEADER config option). However for 64-bit kernels it is OK to have a different kernel version (and size of the image) of the booting and resuming kernels. Hence the above mentioned git commit introduces an regression. This patch fixes it by introducing a 'struct desc_ptr gdt_desc' back in the 'struct saved_context'. However instead of having in the 'save_processor_state' and 'restore_processor_state' the store/load_gdt calls, we are only saving the GDT in the save_processor_state. For the restore path the lgdt operation is done in hibernate_asm_[32|64].S in the 'restore_registers' path. The apt reader of this description will recognize that only 64-bit kernels need this treatment, not 32-bit. This patch adds the logic in the 32-bit path to be more similar to 64-bit so that in the future the unification process can take advantage of this. Suggested-by: "H. Peter Anvin" CC: "Rafael J. Wysocki" Signed-off-by: Konrad Rzeszutek Wilk Acked-by: Rafael J. Wysocki --- arch/x86/include/asm/suspend_32.h | 1 + arch/x86/include/asm/suspend_64.h | 2 ++ arch/x86/kernel/asm-offsets_32.c | 3 +++ arch/x86/kernel/asm-offsets_64.c | 1 + arch/x86/power/cpu.c | 15 ++++++++++----- arch/x86/power/hibernate_asm_32.S | 4 ++++ arch/x86/power/hibernate_asm_64.S | 3 +++ 7 files changed, 24 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/suspend_32.h b/arch/x86/include/asm/suspend_32.h index f6064b7..552d6c9 100644 --- a/arch/x86/include/asm/suspend_32.h +++ b/arch/x86/include/asm/suspend_32.h @@ -15,6 +15,7 @@ struct saved_context { unsigned long cr0, cr2, cr3, cr4; u64 misc_enable; bool misc_enable_saved; + struct desc_ptr gdt_desc; struct desc_ptr idt; u16 ldt; u16 tss; diff --git a/arch/x86/include/asm/suspend_64.h b/arch/x86/include/asm/suspend_64.h index 97b84e0..bc62328 100644 --- a/arch/x86/include/asm/suspend_64.h +++ b/arch/x86/include/asm/suspend_64.h @@ -25,6 +25,8 @@ struct saved_context { u64 misc_enable; bool misc_enable_saved; unsigned long efer; + u16 gdt_pad; /* Unused */ + struct desc_ptr gdt_desc; u16 idt_pad; u16 idt_limit; unsigned long idt_base; diff --git a/arch/x86/kernel/asm-offsets_32.c b/arch/x86/kernel/asm-offsets_32.c index 85d98ab..0ef4bba 100644 --- a/arch/x86/kernel/asm-offsets_32.c +++ b/arch/x86/kernel/asm-offsets_32.c @@ -60,6 +60,9 @@ void foo(void) OFFSET(IA32_RT_SIGFRAME_sigcontext, rt_sigframe, uc.uc_mcontext); BLANK(); + OFFSET(saved_context_gdt_desc, saved_context, gdt_desc); + BLANK(); + /* Offset from the sysenter stack to tss.sp0 */ DEFINE(TSS_sysenter_sp0, offsetof(struct tss_struct, x86_tss.sp0) - sizeof(struct tss_struct)); diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index 1b4754f..e7c798b 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -73,6 +73,7 @@ int main(void) ENTRY(cr3); ENTRY(cr4); ENTRY(cr8); + ENTRY(gdt_desc); BLANK(); #undef ENTRY diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index 6d6e907..1cf5b30 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -25,16 +25,12 @@ #include #ifdef CONFIG_X86_32 -static struct saved_context saved_context; - unsigned long saved_context_ebx; unsigned long saved_context_esp, saved_context_ebp; unsigned long saved_context_esi, saved_context_edi; unsigned long saved_context_eflags; -#else -/* CONFIG_X86_64 */ -struct saved_context saved_context; #endif +struct saved_context saved_context; /** * __save_processor_state - save CPU registers before creating a @@ -67,6 +63,15 @@ static void __save_processor_state(struct saved_context *ctxt) /* CONFIG_X86_64 */ store_idt((struct desc_ptr *)&ctxt->idt_limit); #endif + /* + * We save it here, but restore it only in the hibernate case. + * For ACPI S3 resume, this is loaded via 'early_gdt_desc' in 64-bit + * mode in "secondary_startup_64". In 32-bit mode it is done via + * 'pmode_gdt' in wakeup_start. + */ + ctxt->gdt_desc.size = GDT_SIZE - 1; + ctxt->gdt_desc.address = (unsigned long)get_cpu_gdt_table(smp_processor_id()); + store_tr(ctxt->tr); /* XMM0..XMM15 should be handled by kernel_fpu_begin(). */ diff --git a/arch/x86/power/hibernate_asm_32.S b/arch/x86/power/hibernate_asm_32.S index ad47dae..1d0fa0e 100644 --- a/arch/x86/power/hibernate_asm_32.S +++ b/arch/x86/power/hibernate_asm_32.S @@ -75,6 +75,10 @@ done: pushl saved_context_eflags popfl + /* Saved in save_processor_state. */ + movl $saved_context, %eax + lgdt saved_context_gdt_desc(%eax) + xorl %eax, %eax ret diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S index 9356547..3c4469a 100644 --- a/arch/x86/power/hibernate_asm_64.S +++ b/arch/x86/power/hibernate_asm_64.S @@ -139,6 +139,9 @@ ENTRY(restore_registers) pushq pt_regs_flags(%rax) popfq + /* Saved in save_processor_state. */ + lgdt saved_context_gdt_desc(%rax) + xorq %rax, %rax /* tell the hibernation core that we've just restored the memory */