Re: [Xen-devel] [PATCH] Choose retpoline only when it is safe to use

2018-02-06 Thread Andrew Cooper
On 06/02/2018 09:13, Zhenzhong Duan wrote: > 在 2018/2/6 16:59, Andrew Cooper 写道: >> On 06/02/2018 08:43, Zhenzhong Duan wrote: >>> When ( ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, >>> thunk is set to THUNK_JMP rather than THUNK_RETPOLINE. >>> >>> When (!ibrs && thunk == THUNK_D

Re: [Xen-devel] [PATCH] Choose retpoline only when it is safe to use

2018-02-06 Thread Zhenzhong Duan
在 2018/2/6 16:59, Andrew Cooper 写道: On 06/02/2018 08:43, Zhenzhong Duan wrote: When ( ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, thunk is set to THUNK_JMP rather than THUNK_RETPOLINE. When (!ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, we should do the same

Re: [Xen-devel] [PATCH] Choose retpoline only when it is safe to use

2018-02-06 Thread Andrew Cooper
On 06/02/2018 08:43, Zhenzhong Duan wrote: > When ( ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, > thunk is set to THUNK_JMP rather than THUNK_RETPOLINE. > > When (!ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, > we should do the same. > > Signed-off-by: Zhenzhong

[Xen-devel] [PATCH] Choose retpoline only when it is safe to use

2018-02-06 Thread Zhenzhong Duan
When ( ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, thunk is set to THUNK_JMP rather than THUNK_RETPOLINE. When (!ibrs && thunk == THUNK_DEFAULT && !retpoline_safe() ) is true, we should do the same. Signed-off-by: Zhenzhong Duan --- xen/arch/x86/spec_ctrl.c |4 ++-- 1 fil