Re: rseq/x86: choosing rseq code signature

2019-04-10 Thread Mathieu Desnoyers
- On Apr 10, 2019, at 1:57 PM, Peter Zijlstra pet...@infradead.org wrote: > On Wed, Apr 10, 2019 at 11:47:40AM -0400, Mathieu Desnoyers wrote: >> - On Apr 10, 2019, at 2:54 AM, Peter Zijlstra pet...@infradead.org wrote: >> >> > On Tue, Apr 09, 2019 at 04:43:42PM -0400, Mathieu Desnoyers

Re: rseq/x86: choosing rseq code signature

2019-04-10 Thread Peter Zijlstra
On Wed, Apr 10, 2019 at 11:47:40AM -0400, Mathieu Desnoyers wrote: > - On Apr 10, 2019, at 2:54 AM, Peter Zijlstra pet...@infradead.org wrote: > > > On Tue, Apr 09, 2019 at 04:43:42PM -0400, Mathieu Desnoyers wrote: > >> +/* > >> + * RSEQ_SIG is used with the following privileged

Re: rseq/x86: choosing rseq code signature

2019-04-10 Thread Mathieu Desnoyers
- On Apr 10, 2019, at 2:54 AM, Peter Zijlstra pet...@infradead.org wrote: > On Tue, Apr 09, 2019 at 04:43:42PM -0400, Mathieu Desnoyers wrote: >> +/* >> + * RSEQ_SIG is used with the following privileged instructions, which trap >> in >> user-space: >> + * x86-32:0f 01 3d 53 30 05 53

Re: rseq/x86: choosing rseq code signature

2019-04-10 Thread Peter Zijlstra
On Tue, Apr 09, 2019 at 04:43:42PM -0400, Mathieu Desnoyers wrote: > +/* > + * RSEQ_SIG is used with the following privileged instructions, which trap > in user-space: > + * x86-32:0f 01 3d 53 30 05 53 invlpg 0x53053053 > + * x86-64:0f 01 3d 53 30 05 53 invlpg 0x53053053(%rip) >

Re: rseq/x86: choosing rseq code signature

2019-04-09 Thread Mathieu Desnoyers
- On Apr 9, 2019, at 9:57 PM, Andy Lutomirski l...@kernel.org wrote: > On Tue, Apr 9, 2019 at 5:51 PM Zack Weinberg wrote: >> >> On Tue, Apr 9, 2019 at 4:43 PM Mathieu Desnoyers >> wrote: >> > - On Apr 9, 2019, at 3:32 PM, Mathieu Desnoyers >> > mathieu.desnoy...@efficios.com wrote: >>

Re: rseq/x86: choosing rseq code signature

2019-04-09 Thread Andy Lutomirski
On Tue, Apr 9, 2019 at 5:51 PM Zack Weinberg wrote: > > On Tue, Apr 9, 2019 at 4:43 PM Mathieu Desnoyers > wrote: > > - On Apr 9, 2019, at 3:32 PM, Mathieu Desnoyers > > mathieu.desnoy...@efficios.com wrote: > > > > > > We are about to include the code signature required prior to

Re: rseq/x86: choosing rseq code signature

2019-04-09 Thread Zack Weinberg
On Tue, Apr 9, 2019 at 4:43 PM Mathieu Desnoyers wrote: > - On Apr 9, 2019, at 3:32 PM, Mathieu Desnoyers > mathieu.desnoy...@efficios.com wrote: > > > > We are about to include the code signature required prior to restartable > > sequences abort handlers into glibc, which will make this ABI

Re: rseq/x86: choosing rseq code signature

2019-04-09 Thread Mathieu Desnoyers
- On Apr 9, 2019, at 3:32 PM, Mathieu Desnoyers mathieu.desnoy...@efficios.com wrote: > Hi, > > We are about to include the code signature required prior to restartable > sequences abort handlers into glibc, which will make this ABI choice final. > We need architecture maintainer input on

rseq/x86: choosing rseq code signature

2019-04-09 Thread Mathieu Desnoyers
Hi, We are about to include the code signature required prior to restartable sequences abort handlers into glibc, which will make this ABI choice final. We need architecture maintainer input on that signature value. That code signature is placed before each abort handler, so the kernel can