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As this is >> secret sauce, I can't tell. > > I tried enabling /debug/rseq/debug but many of the daemons on my host > started crash-looping so much that I wasn't able to even run my test. > > Next I tried disabling CONFIG_RSEQ and as expected the issue went > away. I will use that for now to unblock my VFIO testing. > > I have reported the tcmalloc regression internally within Google to > figure out what next step they want to take. Note that I've proposed to help out the tcmalloc people a few times in the past years to fix this, but I've been told that it was not a priority on their end, and that they would not be able to even test whatever I would come up with. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com