You said this might have been resolved differently anyway with the newest 
kernel having again hle/rtm enabled - I haven't heard about it but that would 
probably be even better.
Lets see on the kernel side.
- Fixes for CVE-2019-11135 got added in 4.15.0-69.78
- This was reported against 4.15.0-70
- Wondering about 4.15.0-72 being ok again

Reading the latest state of 
Documentation/admin-guide/hw-vuln/tsx_async_abort.rst shows:
https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html#mitigation-control-on-the-kernel-command-line

212   tsx=on     tsx_async_abort=full         The system will use VERW to clear 
CPU
213                                           buffers. Cross-thread attacks are 
still
214                                           possible on SMT machines.
215   tsx=on     tsx_async_abort=full,nosmt   As above, cross-thread attacks on 
SMT
216                                           mitigated.
217   tsx=on     tsx_async_abort=off          The system is vulnerable.
218   tsx=off    tsx_async_abort=full         TSX might be disabled if microcode
219                                           provides a TSX control MSR. If so,
220                                           system is not vulnerable.
221   tsx=off    tsx_async_abort=full,nosmt   Ditto
222   tsx=off    tsx_async_abort=off          ditto

Maybe the initial take was tsx=off which would switch off those flags. But now 
is any of the tsx=on but with full mitigations? But I'm guessing at this point.
I have not found a clear kernel change since then (not until 4.15.0-73.82, but 
even less so  between .70 and .72) that would change these.
The only related "- x86/speculation/taa: Fix printing of TAA_MSG_SMT on 
IBRS_ALL CPUs" seems to only affect print output, but not change behavior.

Furthermore none of the systems I have has got hle/rtm back since then.


@Nobuto - has your system any of the above kernel parameters set manually?


I haven't heard from this by sbeattie or others after my last update.
Lets ping security to be sure this hasn't been forgotten.
(I have done that on IRC as well)
@Security - any updates on this from your side?

** CVE added: https://cve.mitre.org/cgi-bin/cvename.cgi?name=2019-11135

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https://bugs.launchpad.net/bugs/1853200

Title:
  cpu features hle and rtm disabled for security are present in
  /usr/share/libvirt/cpu_map.xml

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