From 3a23208e69679597e767cf3547b1a30dd845d9b5 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 24 Apr 2015 17:31:35 +0200 Subject: [PATCH] x86/entry: Define 'cpu_current_top_of_stack' for 64-bit code 32-bit code has PER_CPU_VAR(cpu_current_top_of_stack). 64-bit code uses somewhat more obscure: PER_CPU_VAR(cpu_tss + TSS_sp0). Define the 'cpu_current_top_of_stack' macro on CONFIG_X86_64 as well so that the PER_CPU_VAR(cpu_current_top_of_stack) expression can be used in both 32-bit and 64-bit code. Signed-off-by: Denys Vlasenko Cc: Alexei Starovoitov Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Will Drewry Link: http://lkml.kernel.org/r/1429889495-27850-3-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/ia32/ia32entry.S | 4 ++-- arch/x86/include/asm/thread_info.h | 10 ++++------ arch/x86/kernel/entry_64.S | 2 +- arch/x86/xen/xen-asm_64.S | 5 +++-- 4 files changed, 10 insertions(+), 11 deletions(-) diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index 1b1330c07971..63450a596800 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -113,7 +113,7 @@ ENTRY(ia32_sysenter_target) * it is too small to ever cause noticeable irq latency. */ SWAPGS_UNSAFE_STACK - movq PER_CPU_VAR(cpu_tss + TSS_sp0), %rsp + movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp ENABLE_INTERRUPTS(CLBR_NONE) /* Zero-extending 32-bit regs, do not remove */ @@ -346,7 +346,7 @@ ENTRY(ia32_cstar_target) SWAPGS_UNSAFE_STACK movl %esp,%r8d CFI_REGISTER rsp,r8 - movq PER_CPU_VAR(cpu_tss + TSS_sp0),%rsp + movq PER_CPU_VAR(cpu_current_top_of_stack),%rsp ENABLE_INTERRUPTS(CLBR_NONE) /* Zero-extending 32-bit regs, do not remove */ diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 472288962c99..225ee545e1a0 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -195,16 +195,14 @@ static inline unsigned long current_stack_pointer(void) #else /* !__ASSEMBLY__ */ +#ifdef CONFIG_X86_64 +# define cpu_current_top_of_stack (cpu_tss + TSS_sp0) +#endif + /* Load thread_info address into "reg" */ -#ifdef CONFIG_X86_32 #define GET_THREAD_INFO(reg) \ _ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \ _ASM_SUB $(THREAD_SIZE),reg ; -#else -#define GET_THREAD_INFO(reg) \ - _ASM_MOV PER_CPU_VAR(cpu_tss + TSS_sp0),reg ; \ - _ASM_SUB $(THREAD_SIZE),reg ; -#endif /* * ASM operand which evaluates to a 'thread_info' address of diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index c13b86b40176..09c3f9e0e07e 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -216,7 +216,7 @@ ENTRY(system_call) GLOBAL(system_call_after_swapgs) movq %rsp,PER_CPU_VAR(rsp_scratch) - movq PER_CPU_VAR(cpu_tss + TSS_sp0),%rsp + movq PER_CPU_VAR(cpu_current_top_of_stack),%rsp /* Construct struct pt_regs on stack */ pushq_cfi $__USER_DS /* pt_regs->ss */ diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S index 5aa7ec607b9e..04529e620559 100644 --- a/arch/x86/xen/xen-asm_64.S +++ b/arch/x86/xen/xen-asm_64.S @@ -16,6 +16,7 @@ #include #include #include +#include #include @@ -54,7 +55,7 @@ ENTRY(xen_sysret64) * still with the kernel gs, so we can easily switch back */ movq %rsp, PER_CPU_VAR(rsp_scratch) - movq PER_CPU_VAR(cpu_tss + TSS_sp0), %rsp + movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp pushq $__USER_DS pushq PER_CPU_VAR(rsp_scratch) @@ -73,7 +74,7 @@ ENTRY(xen_sysret32) * still with the kernel gs, so we can easily switch back */ movq %rsp, PER_CPU_VAR(rsp_scratch) - movq PER_CPU_VAR(cpu_tss + TSS_sp0), %rsp + movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp pushq $__USER32_DS pushq PER_CPU_VAR(rsp_scratch) -- 2.20.1