mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-12-28 10:15:32 -05:00
A VMM may send a non-fatal signal to its threads, including vCPU tasks, at any time, and thus may signal vCPU tasks during KVM_RUN. If a vCPU task receives the signal while its trying to spawn the huge page recovery vhost task, then KVM_RUN will fail due to copy_process() returning -ERESTARTNOINTR. Rework call_once() to mark the call complete if and only if the called function succeeds, and plumb the function's true error code back to the call_once() invoker. This provides userspace with the correct, non-fatal error code so that the VMM doesn't terminate the VM on -ENOMEM, and allows subsequent KVM_RUN a succeed by virtue of retrying creation of the NX huge page task. Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> [implemented the kvm user side] Signed-off-by: Keith Busch <kbusch@kernel.org> Message-ID: <20250227230631.303431-3-kbusch@meta.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>