x86/entry/64: Make cpu_entry_area.tss read-only

[mirror_ubuntu-artful-kernel.git] / arch / x86 / kernel / traps.c

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index d9debdafe7a6f793dcaf15437c9c5120402c0ecc..14b462eefa17bcbc6dbc0522ff442c964af7df41 100644 (file)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -376,7 +376,7 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
                regs->cs == __KERNEL_CS &&
                regs->ip == (unsigned long)native_irq_return_iret)
        {
-               struct pt_regs *gpregs = (struct pt_regs *)this_cpu_read(cpu_tss.x86_tss.sp0) - 1;
+               struct pt_regs *gpregs = (struct pt_regs *)this_cpu_read(cpu_tss_rw.x86_tss.sp0) - 1;
 
                /*
                 * regs->sp points to the failing IRET frame on the
@@ -661,7 +661,7 @@ struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s)
         * exception came from the IRET target.
         */
        struct bad_iret_stack *new_stack =
-               (struct bad_iret_stack *)this_cpu_read(cpu_tss.x86_tss.sp0) - 1;
+               (struct bad_iret_stack *)this_cpu_read(cpu_tss_rw.x86_tss.sp0) - 1;
 
        /* Copy the IRET target to the new stack. */
        memmove(&new_stack->regs.ip, (void *)s->regs.sp, 5*8);
@@ -826,13 +826,6 @@ dotraplinkage void do_debug(struct pt_regs *regs, long error_code)
        debug_stack_usage_dec();
 
 exit:
-       /*
-        * This is the most likely code path that involves non-trivial use
-        * of the SYSENTER stack.  Check that we haven't overrun it.
-        */
-       WARN(this_cpu_read(cpu_tss.SYSENTER_stack_canary) != STACK_END_MAGIC,
-            "Overran or corrupted SYSENTER stack\n");
-
        ist_exit(regs);
 }
 NOKPROBE_SYMBOL(do_debug);
@@ -992,6 +985,9 @@ void __init trap_init(void)
 {
        int i;
 
+       /* Init cpu_entry_area before IST entries are set up */
+       setup_cpu_entry_areas();
+
 #ifdef CONFIG_EISA
        void __iomem *p = early_ioremap(0x0FFFD9, 4);