From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chen Yu Subject: [PATCH 03/12][v4] x86-32/asm/power: Create stack frames in hibernate_asm_32.S Date: Fri, 21 Sep 2018 14:26:47 +0800 Message-ID: References: Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Thomas Gleixner , "Rafael J. Wysocki" Cc: Pavel Machek , Len Brown , Zhimin Gu , Chen Yu , x86@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" List-Id: linux-pm@vger.kernel.org From: Zhimin Gu swsusp_arch_suspend() is callable non-leaf function which doesn't honor CONFIG_FRAME_POINTER, which can result in bad stack traces. Also it's not annotated as ELF callable function which can confuse tooling. Create a stack frame for it when CONFIG_FRAME_POINTER is enabled and give it proper ELF function annotation. Also in this patch introduces the restore_registers() symbol and gives it ELF function annotation, thus to prepare for later register restore. Analogous changes were made for 64bit before in Commit ef0f3ed5a4ac (x86/asm/power: Create stack frames in hibernate_asm_64.S) and Commit 4ce827b4cc58 (x86/power/64: Fix hibernation return address corruption) Cc: "Rafael J. Wysocki" Signed-off-by: Zhimin Gu Signed-off-by: Chen Yu --- arch/x86/include/asm/suspend_32.h | 4 ++++ arch/x86/power/hibernate_asm_32.S | 9 +++++++++ 2 files changed, 13 insertions(+) diff --git a/arch/x86/include/asm/suspend_32.h b/arch/x86/include/asm/suspend_32.h index 8be6afb58471..fdbd9d7b7bca 100644 --- a/arch/x86/include/asm/suspend_32.h +++ b/arch/x86/include/asm/suspend_32.h @@ -32,4 +32,8 @@ struct saved_context { unsigned long return_address; } __attribute__((packed)); +/* routines for saving/restoring kernel state */ +extern char core_restore_code[]; +extern char restore_registers[]; + #endif /* _ASM_X86_SUSPEND_32_H */ diff --git a/arch/x86/power/hibernate_asm_32.S b/arch/x86/power/hibernate_asm_32.S index 6e56815e13a0..671d38d0d931 100644 --- a/arch/x86/power/hibernate_asm_32.S +++ b/arch/x86/power/hibernate_asm_32.S @@ -12,6 +12,7 @@ #include #include #include +#include .text @@ -24,8 +25,11 @@ ENTRY(swsusp_arch_suspend) pushfl popl saved_context_eflags + FRAME_BEGIN call swsusp_save + FRAME_END ret +ENDPROC(swsusp_arch_suspend) ENTRY(restore_image) movl mmu_cr4_features, %ecx @@ -58,6 +62,10 @@ copy_loop: .p2align 4,,7 done: + + /* code below belongs to the image kernel */ + .align PAGE_SIZE +ENTRY(restore_registers) /* go back to the original page tables */ movl $swapper_pg_dir, %eax subl $__PAGE_OFFSET, %eax @@ -83,3 +91,4 @@ done: xorl %eax, %eax ret +ENDPROC(restore_registers) -- 2.17.1