LoongArch: KVM: Return the actual error code in kvm_ipi_create()

The kvm_ipi_create() function registers the IPI device on the IOCSR
bus. The error path currently discards the actual error code returned
by kvm_io_bus_register_dev() and returns -EFAULT instead:

      ret = kvm_io_bus_register_dev(kvm, KVM_IOCSR_BUS, IOCSR_IPI_BASE,
				      IOCSR_IPI_SIZE, device);
      mutex_unlock(&kvm->slots_lock);
      if (ret < 0) {
          kvm_pr_unimpl("%s: Initialize IOCSR dev failed, ret = %d\n",
			      __func__, ret);
          goto err;
      }
      ...
  err:
      kfree(s);
      return -EFAULT;

kvm_io_bus_register_dev() fails with -ENOMEM or -ENOSPC, so userspace
creating a KVM_DEV_TYPE_LOONGARCH_IPI device is told that it passed a
bad address when the real problem is that the host is out of memory or
out of IOCSR bus slots. -EFAULT is reserved for faulting user addresses,
and the remaining -EFAULT returns in this file are get_user() failures,
where it is correct.

Free the IPI state and propagate the error directly after cleanup. The
error label has a single user, so handling the failure in place removes
the label as well. This matches kvm_eiointc_create() which already frees
its state and propagates the actual kvm_io_bus_register_dev() error code
unchanged.

Only compile-tested.

Fixes: c532de5a67a7 ("LoongArch: KVM: Add IPI device support")
Assisted-by: Cursor:claude-opus-5
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Suggested-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

0 files changed, 0 insertions, 0 deletions