Hi, On 06/11/16 at 17:41 -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().
How can one know what glibc does on a given CPU? (preferably without access to the hardware) I could try to run an archive rebuild on hardware where glibc leverages TSX to see what happens. Lucas