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From: Vince Weaver <vincent.weaver@maine.edu>
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Subject: Re: perf: WARNING: kernel/events/core.c:4893 perf_mmap_close
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and as the fuzzing continues I started to get these, a bit worrying.

[ 6501.254564] Slab corruption (Tainted: G        W      ): task_struct start=ffff8800c072e000, len=5760
[ 6501.264971] 010: 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  jkkkkkkkkkkkkkkk
[ 6501.273650] Single bit error detected. Probably bad RAM.
[ 6501.279889] Run memtest86+ or a similar memory test tool.

[19535.776930] Slab corruption (Tainted: G        W      ): task_struct start=ffff8800c720e2c0, len=5760
[19535.787191] 010: 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  jkkkkkkkkkkkkkkk
[19535.795771] Single bit error detected. Probably bad RAM.
[19535.801872] Run memtest86+ or a similar memory test tool.

Is it possible this was a decrement-after-free bug?

It could also be bad RAM I suppose, I was using this machine to do some 
pretty intense DRAM RAPL validation which involved a lot of DIMM swapping 
so it is conceivable that I managed to break something.

Also lots of
[ 4714.797333] perfevents: irq loop stuck!
errors as always, I think we decided those were probably a hardware issue.