Red Hat Bugzilla – Bug 1256513
Support libipt for Broadwell+ Intel(R) Processor Trace
Last modified: 2016-11-15 05:11:46 EST
Description of problem:
DTS/Fedora/RHEL GDB does not yet support new functionality of branch tracing available in Broadwell + Skylake CPUs:
- record btrace pt
To get the feature one could either package new rpm libipt or bundle libipt with GDB (either dynamically or statically). libipt will be a new Fedora package in Fedora Rawhide but that does not seem to be quick enough for DTS-4.0.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
gdb -ex start -ex 'record btrace pt'
Target does not support branch tracing.
<nothing> ("info record" then should display PT is active)
Fedora Rawhide libipt new package (.spec file) for review: Bug 1258572
So technically I can include it into DTS-4.0.
gdb.rawhide+libipt.rawhide are built:
"intel_pt_interrupt" is still not found in:
But it is now present thanks to RHEL-7.3 kernel Bug 1270539 in:
It requires Intel Broadwell or higher where does exist:
and also there is in CPU flags:
grep -w intel_pt /proc/cpuinfo
Successfully tested it in Beaker with kernel-hw loaned machine:
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.