On Mon, Nov 27, 2017 at 11:22:41AM +0100, Peter Zijlstra wrote: > Could be a simple as this.. but I've not tested. > > > diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c > index f4f4ab8525bd..1be393a97421 100644 > --- a/arch/x86/kernel/cpu/common.c > +++ b/arch/x86/kernel/cpu/common.c > @@ -1442,7 +1442,10 @@ void syscall_init(void) > (entry_SYSCALL_64_trampoline - _entry_trampoline); > > wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); > - wrmsrl(MSR_LSTAR, SYSCALL64_entry_trampoline); > + if (kaiser_enabled) > + wrmsrl(MSR_LSTAR, SYSCALL64_entry_trampoline); > + else > + wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); > > #ifdef CONFIG_IA32_EMULATION > wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat); Seems to work: root@ivb-ep:~# rdmsr --all 0xc0000082 | uniq ffffffff81beb780 root@ivb-ep:~# grep ffffffff81beb780 /proc/kallsyms ffffffff81beb780 T entry_SYSCALL_64 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
