diff options
| -rw-r--r-- | i386/i386/ldt.c | 3 | ||||
| -rw-r--r-- | x86_64/locore.S | 4 |
2 files changed, 5 insertions, 2 deletions
diff --git a/i386/i386/ldt.c b/i386/i386/ldt.c index 4d7ec19a..5db36426 100644 --- a/i386/i386/ldt.c +++ b/i386/i386/ldt.c @@ -27,6 +27,7 @@ * "Local" descriptor table. At the moment, all tasks use the * same LDT. */ +#include <mach/machine/eflags.h> #include <mach/machine/vm_types.h> #include <mach/xen.h> @@ -75,7 +76,7 @@ ldt_fill(struct real_descriptor *myldt, struct real_descriptor *mygdt) wrmsr(MSR_REG_EFER, rdmsr(MSR_REG_EFER) | MSR_EFER_SCE); wrmsr(MSR_REG_LSTAR, (vm_offset_t)syscall64); wrmsr(MSR_REG_STAR, ((((long)USER_CS - 16) << 16) | (long)KERNEL_CS) << 32); - wrmsr(MSR_REG_FMASK, 0); // ? + wrmsr(MSR_REG_FMASK, EFL_IF | EFL_IOPL_USER); #else /* defined(__x86_64__) && ! defined(USER32) */ fill_ldt_gate(myldt, USER_SCALL, (vm_offset_t)&syscall, KERNEL_CS, diff --git a/x86_64/locore.S b/x86_64/locore.S index 4d61d618..2938e430 100644 --- a/x86_64/locore.S +++ b/x86_64/locore.S @@ -1390,9 +1390,10 @@ ENTRY(syscall64) mov %r11,%rbx /* prepare for error handling */ mov %r10,%rcx /* fix arg3 location according to C ABI */ - /* switch to kernel stack */ + /* switch to kernel stack, then we can enable interrupts */ CPU_NUMBER(%r11) movq CX(EXT(kernel_stack),%r11),%rsp + sti /* Now we have saved state and args 1-6 are in place. * Before invoking the syscall we do some bound checking and, @@ -1453,6 +1454,7 @@ _syscall64_check_for_ast: _syscall64_restore_state: /* Restore thread state and return to user using sysret. */ + cli /* block interrupts when using the user stack in kernel space */ movq CX(EXT(active_threads),%r11),%r11 /* point to current thread */ movq TH_PCB(%r11),%r11 /* point to pcb */ addq $ PCB_ISS,%r11 /* point to saved state */ |