Bug#842796: libc recently more aggressive about pthread locks in stable ?

[Henrique de Moraes Holschuh]

On Sun, 06 Nov 2016, Ben Hutchings wrote:
> It's worth noting that TSX is broken in 'Haswell' processors and is
> supposed to be disabled via a microcode update.  I don't know whether
> glibc avoids using it on these processors if the microcode update is
> not applied.  (Linux doesn't appear to hide the feature flags.)

It does avoid it.  For glibc libpthreads, Debian has blacklisted Intel
TSX use [in libpthreads] on all of Haswell and much of Broadwell.

But anything else *will* attempt to use it, people query cpuid directly
for these things.  You need a hypervisor that filters cpuid().

-- 
  Henrique Holschuh