Grzegorz Jaszczyk 8eae8e0d2d crosvm: improve suspend implementation ... As part of commit cadc84b32a the crosvm suspend command has been extended to generating sleep button injection in order to put VM in suspend state. Additionally the crosvm suspend command completed after the guest entered proper power state. Nevertheless in some circumstances above implementation caused issues. E.g. when the guest with pass-through devices entered run-time device suspension, triggering a subsequent system suspend request fails and makes VM inaccessible. It is because before entering system suspension, devices which entered device run-time suspension needs to be resumed. Therefore in problematic scenario: - VmRequest::Suspend was triggered and it resulted with blocking till guest entered proper suspend state - during VM suspension process some pci config write accesses are made, which in some cases triggers write_msi_reg-> write_msi_capability-> add_msi_route, which underneath sends VmIrqRequest::AddMsiRoute request - above VmIrqRequest::AddMsiRoute request can't be satisfied since VmRequest::Suspend made the run_control wait loop busy waiting and preventing further requests to be processed In order to fix the above issue, instead of busy waiting directly in the run_control wait loop for suspend notification, spawn a new thread, which will generate the acpi power button and start busy waiting for a notification that the VM actually entered suspend state. This allows to postpone sending response over the control tube indicating that the 'crosvm suspend ...' command completed and in the same time process other Vm*Requests. Mentioned postponement of 'crosvm suspend ..' completion is crucial since the full system suspension needs to be blocked till VM actually enters proper suspend state. BUG=b:248462336 TEST=With a setup where some device is pass-through to the VM and --force-s2idle flag is used: wait till pass-through device enters run-time suspend state and trigger "crosvm suspend /run/vm/vm.<hash>/crosvm.sock" followed by "crosvm resume ..". Also make sure that full system suspension/resumption doesn't make VM inaccessible anymore. Change-Id: Ic23461a78a62d2116cf5674c71d89f4f86ad96c3 Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3944915 Reviewed-by: Daniel Verkamp <dverkamp@chromium.org> Commit-Queue: Grzegorz Jaszczyk <jaszczyk@google.com> Reviewed-by: Noah Gold <nkgold@google.com>		2022-11-16 21:38:29 +00:00
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src	crosvm: improve suspend implementation	2022-11-16 21:38:29 +00:00
Cargo.toml	crosvm: migrate to Rust 2021 edition	2022-03-09 01:16:03 +00:00