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On 2026-01-26 17:35, Mathieu Desnoyers wrote: > On 2026-01-26 17:27, David Matlack wrote: >> On Mon, Jan 26, 2026 at 1:51 PM Thomas Gleixner wrote: > [...] >>>> Perhaps this is the nudge Google needs to go fix this. >>> >>> The real question is whether the segfault is triggered from the rseq >>> sanity checks or if the application segfaults becauses it relies on >>> something something which is not guaranteed by the ABI. 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