Fix fast_page_fault_helper crashing instead of causing page faults #5054
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## main #5054 +/- ##
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Coverage 83.19% 83.19%
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Files 247 247
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Add spaces before parenthesis Suggested-by: Babis Chalios <[email protected]> Signed-off-by: Patrick Roy <[email protected]>
mmap should never fail, but having the check for failure after the memset is just wrong. Signed-off-by: Patrick Roy <[email protected]>
-1 wraps around to 255, which in case of commands executed over SSH clashes with SSH defined return codes. Signed-off-by: Patrick Roy <[email protected]>
Without calling sigprocmask, the SIGUSR1 that we're using will actually just kill the process instead of waking it up, as sigwait can only be used to wait for _pending_ signals, but signals are only marked as pending if they're blocked by a signal mask. If they're not blocked, they will instead call signal handlers, which will in this case just kill the process. This does mean that this program never worked the intended way, which also kinda proves it was not needed to show the different in page faults between huge pages and normal pages (test_ept_violation_count). Signed-off-by: Patrick Roy <[email protected]>
Currently, all tests that want to make use of UFFD import UFFD related functions from test_uffd.py. That's a bit awkward, so move them into their own utility module. Signed-off-by: Patrick Roy <[email protected]>
There's really no use in having this be a fixture, it's just a dictionary - it used to be a fixture because we were building the binaries inside of the test framework (and so each call to it as a function would trigger compilations), but now that we pre-compile everything that's no longer something to worry about. Signed-off-by: Patrick Roy <[email protected]>
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ShadowCurse
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kalyazin
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Make page fault helper used in test_ept_violation_count actually cause page faults post restore. Currently, it is just crashing because the signal that is supposed to wake it up is actually killing it, due to no signal mask being installed.
Surrounded by a few refactors/fixes that came from me working on a page fault latency test before realizing that my approach was fundamentally flawed and I had to throw most of it away.
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how they are solving the problem in a clear and encompassing way.
in the PR.
CHANGELOG.md.Runbook for Firecracker API changes.
integration tests.
TODO.rust-vmm.