Re: [RFC] x86: Speculative execution warnings

2019-05-16 Thread Nadav Amit
> On May 14, 2019, at 10:15 AM, Andy Lutomirski wrote: > > > > On May 14, 2019, at 10:00 AM, Nadav Amit wrote: > >>> On May 14, 2019, at 1:00 AM, Paul Turner wrote: >>> >>> From: Nadav Amit >>> Date: Fri, May 10, 2019 at 7:45 PM >>> To: >>> Cc: Borislav Petkov, , Nadav Amit, Andy >>> Luto

Re: [RFC] x86: Speculative execution warnings

2019-05-14 Thread Andy Lutomirski
On May 14, 2019, at 10:00 AM, Nadav Amit wrote: >> On May 14, 2019, at 1:00 AM, Paul Turner wrote: >> >> From: Nadav Amit >> Date: Fri, May 10, 2019 at 7:45 PM >> To: >> Cc: Borislav Petkov, , Nadav Amit, Andy >> Lutomirsky, Ingo Molnar, Peter Zijlstra, Thomas Gleixner, Jann Horn >> >>> I

Re: [RFC] x86: Speculative execution warnings

2019-05-14 Thread Nadav Amit
> On May 14, 2019, at 1:00 AM, Paul Turner wrote: > > From: Nadav Amit > Date: Fri, May 10, 2019 at 7:45 PM > To: > Cc: Borislav Petkov, , Nadav Amit, Andy > Lutomirsky, Ingo Molnar, Peter Zijlstra, Thomas Gleixner, Jann Horn > >> It may be useful to check in runtime whether certain assertions

Re: [RFC] x86: Speculative execution warnings

2019-05-14 Thread Paul Turner
From: Nadav Amit Date: Fri, May 10, 2019 at 7:45 PM To: Cc: Borislav Petkov, , Nadav Amit, Andy Lutomirsky, Ingo Molnar, Peter Zijlstra, Thomas Gleixner, Jann Horn > It may be useful to check in runtime whether certain assertions are > violated even during speculative execution. This can allow t

Re: [RFC] x86: Speculative execution warnings

2019-05-10 Thread Randy Dunlap
On 5/10/19 12:25 PM, Nadav Amit wrote: > It may be useful to check in runtime whether certain assertions are > violated even during speculative execution. This can allow to avoid > adding unnecessary memory fences and at the same time check that no data > leak channels exist. > > For example, addi

[RFC] x86: Speculative execution warnings

2019-05-10 Thread Nadav Amit
It may be useful to check in runtime whether certain assertions are violated even during speculative execution. This can allow to avoid adding unnecessary memory fences and at the same time check that no data leak channels exist. For example, adding such checks can show that allocating zeroed page