Bug#850182: Please disable TSX in stretch and backport to jessie

[Henrique de Moraes Holschuh <hmh@debian.org>]

On Thu, 05 Jan 2017, Aurelien Jarno wrote:
> On 2017-01-05 09:15, Henrique de Moraes Holschuh wrote:
> > Also valid for S/390x, POWER, and anything else where glibc 2.24
> > supports hardware lock elision.
> 
> Do you have some pointers about the different behaviour of locking
> primitives on S/390 and POWER? They accept to "unlock" already unlocked

I got it from one of the multiple places describing TSX, were it was
compared to other implementations.  Can't find the source right now,
though, so I apologise :-(

> mutexes and I haven't seen any bug report about that so far. There have
> been a few issues fixed on the glibc and gcc side at the beginning, but
> it hasn't been the case for quite some time now.

I'd say whatever information source I got it from was likely wrong,
then.  Which might actually be a good thing...

Since we *do* have boxes running S/390x and POWER with hardware lock
elision enabled, I propose we could simply test for it if there is any
doubt.

So, it looks like hardware lock elision should be disabled only for
x86/x86-64.

-- 
  Henrique Holschuh