Re: [RFC PATCH v1 26/37] KVM: selftests: guest_memfd: Test that shared/private status is consistent across processes

Ackerley Tng [off-list ref] writes:

From: Sean Christopherson <seanjc@google.com>

Add a test to verify that a guest_memfd's shared/private status is
consistent across processes.

Missed copying Sean's note from [1]. Rephrased:

Test that on shared to private conversion, any shared pages previously
mapped in any process are unmapped from all processes.

[1] https://lore.kernel.org/all/aN7U1ewx8dNOKl1n@google.com/ (local)

The test forks a child process after creating the shared guest_memfd
region so that the second process exists alongside the main process for the
entire test.

The processes then take turns to access memory to check that the
shared/private status is consistent across processes.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Co-developed-by: Ackerley Tng <redacted>
Signed-off-by: Ackerley Tng <redacted>
---
 .../kvm/guest_memfd_conversions_test.c        | 74 +++++++++++++++++++
 1 file changed, 74 insertions(+)


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