diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c index 70dd8e5c6889..1c44b53cb15b 100644 --- a/arch/x86_64/kernel/process.c +++ b/arch/x86_64/kernel/process.c @@ -781,10 +781,16 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) } case ARCH_GET_GS: { unsigned long base; + unsigned gsindex; if (task->thread.gsindex == GS_TLS_SEL) base = read_32bit_tls(task, GS_TLS); - else if (doit) - rdmsrl(MSR_KERNEL_GS_BASE, base); + else if (doit) { + asm("movl %%gs,%0" : "=r" (gsindex)); + if (gsindex) + rdmsrl(MSR_KERNEL_GS_BASE, base); + else + base = task->thread.gs; + } else base = task->thread.gs; ret = put_user(base, (unsigned long __user *)addr);