Re: libc recently more aggressive about pthread locks in stable ?
On Sun, 06 Nov 2016, Adrian Bunk wrote:
> On Sun, Nov 06, 2016 at 05:41:34PM -0200, Henrique de Moraes Holschuh wrote:
> > 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().
>
> All users who are using intel-microcode from non-free instead of running
> outdated microcode with known errata should be OK here?
Last time I checked, it looked like an yes for Skylake as far as Intel
TSX is concerned.
I don't know about the other processors, such as Broadwell-E.
--
Henrique Holschuh
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