From 491eccb721c2ee67250273a96e4515fb5b423337 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 25 Jun 2008 00:19:15 -0400 Subject: [PATCH] x86/paravirt: define PARA_INDIRECT for indirect asm calls On 32-bit it's best to use a %cs: prefix to access memory where the other segments may not bet set up properly yet. On 64-bit it's best to use a rip-relative addressing mode. Define PARA_INDIRECT() to abstract this and generate the proper addressing mode in each case. Signed-off-by: Jeremy Fitzhardinge Cc: xen-devel Cc: Stephen Tweedie Cc: Eduardo Habkost Cc: Mark McLoughlin Signed-off-by: Ingo Molnar --- include/asm-x86/paravirt.h | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h index 198293bed46..82cdcde4b22 100644 --- a/include/asm-x86/paravirt.h +++ b/include/asm-x86/paravirt.h @@ -1455,51 +1455,53 @@ static inline unsigned long __raw_local_irq_save(void) #define PV_RESTORE_REGS popq %rdx; popq %rcx; popq %rdi; popq %rax #define PARA_PATCH(struct, off) ((PARAVIRT_PATCH_##struct + (off)) / 8) #define PARA_SITE(ptype, clobbers, ops) _PVSITE(ptype, clobbers, ops, .quad, 8) +#define PARA_INDIRECT(addr) *addr(%rip) #else #define PV_SAVE_REGS pushl %eax; pushl %edi; pushl %ecx; pushl %edx #define PV_RESTORE_REGS popl %edx; popl %ecx; popl %edi; popl %eax #define PARA_PATCH(struct, off) ((PARAVIRT_PATCH_##struct + (off)) / 4) #define PARA_SITE(ptype, clobbers, ops) _PVSITE(ptype, clobbers, ops, .long, 4) +#define PARA_INDIRECT(addr) *%cs:addr #endif #define INTERRUPT_RETURN \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_iret), CLBR_NONE, \ - jmp *%cs:pv_cpu_ops+PV_CPU_iret) + jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_iret)) #define DISABLE_INTERRUPTS(clobbers) \ PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_disable), clobbers, \ - PV_SAVE_REGS; \ - call *%cs:pv_irq_ops+PV_IRQ_irq_disable; \ + PV_SAVE_REGS; \ + call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_disable); \ PV_RESTORE_REGS;) \ #define ENABLE_INTERRUPTS(clobbers) \ PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_enable), clobbers, \ - PV_SAVE_REGS; \ - call *%cs:pv_irq_ops+PV_IRQ_irq_enable; \ + PV_SAVE_REGS; \ + call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable); \ PV_RESTORE_REGS;) #define ENABLE_INTERRUPTS_SYSCALL_RET \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_irq_enable_syscall_ret),\ CLBR_NONE, \ - jmp *%cs:pv_cpu_ops+PV_CPU_irq_enable_syscall_ret) + jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_irq_enable_syscall_ret)) #ifdef CONFIG_X86_32 -#define GET_CR0_INTO_EAX \ - push %ecx; push %edx; \ - call *pv_cpu_ops+PV_CPU_read_cr0; \ +#define GET_CR0_INTO_EAX \ + push %ecx; push %edx; \ + call PARA_INDIRECT(pv_cpu_ops+PV_CPU_read_cr0); \ pop %edx; pop %ecx #else #define SWAPGS \ PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_swapgs), CLBR_NONE, \ PV_SAVE_REGS; \ - call *pv_cpu_ops+PV_CPU_swapgs; \ + call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs); \ PV_RESTORE_REGS \ ) -#define GET_CR2_INTO_RCX \ - call *pv_mmu_ops+PV_MMU_read_cr2; \ - movq %rax, %rcx; \ +#define GET_CR2_INTO_RCX \ + call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2); \ + movq %rax, %rcx; \ xorq %rax, %rax; #endif -- 2.41.1