Re: [Qemu-devel] Provide safe_syscall for s390x

[Richard Henderson]

On 10/17/2016 03:55 AM, Christian Borntraeger wrote:
> On 10/17/2016 10:26 AM, Thomas Huth wrote:
> > On 14.10.2016 20:58, Michael Tokarev wrote:
> > > Hi.
> > >
> > > This commit: c9bc3437a905b660561a26cd4ecc64579843267b
> > > Author: Richard Henderson <address@hidden>
> > > Date:   Tue Jun 21 17:32:12 2016 -0700
> > >
> > >     linux-user: Provide safe_syscall for s390x
> > >
> > > does not build on debian unstable porterbox for s390x, with
> > > the following error message:
> > >
> > > linux-user/host/s390x/safe-syscall.inc.S: Assembler messages:
> > > linux-user/host/s390x/safe-syscall.inc.S:75: Error: Unrecognized opcode:
> > > `lt'
> > > rules.mak:72: recipe for target 'linux-user/safe-syscall.o' failed
> > >
> > > Since I know nothing about s390, I've no idea what's at fault
> > > here... :)  Thought I'd report this :)
> >
> > "lt" seems to be a newer s390x opcode which has been added to the
> > architecture within the last ten years or so. So maybe you've got to add
> > some "-march=xxx" flag when compiling this file?
> > Could you maybe start with finding out the exact comand line that is
> > used to compile this file?
>
> Yes, lt was added with the extended immidiate facility. So either use 
> -march=z9-109 (introduced in
> 2005) or replace the lt with an l + ltr to also run on older models.

Whoops.  I'd forgotten that RHEL defaults to z196 these days.  This piece of 
code is certainly not important enough to conditionalize on newer hardware. 
I'll put together a patch.


r~