Friendly map create errors, document rlimit and perf ring garbage #94
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ti-mo
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Hi @lmb, is this good to go? Any other feedback? |
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…reproducer A patch for this was submitted upstream: https://lore.kernel.org/patchwork/patch/1244339. Promises about the buffer's alignment were also removed because they were inacurrate. The `perf_event_open` man page is incorrect, and there's another bug in the kernel that causes these buffers to be unaligned.
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Hi all,
While migrating a project off of gobpf, I encountered some issues loading an ELF binary, most of which have been addressed below. There's another part that deals with overwriting the binary's
versionsection with the running kernel'sLINUX_VERSION_CODE, but that I'd like to address in another PR.The removal of BTF requirements in data sections and the rlimit changes might need some extra test coverage, but please let me know what you think before I get started on that.
I've added a bit more detailed info about the perf event buffer underrun in the commit that introduced it:
I think I might've stumbled across a kernel bug, but looking at bcc and gobpf, it seems like many userspace libraries already depend on that behaviour by now and discard those bytes by default. Raw perf events are 64-bit aligned, but the test case wasn't.