vfio/nvgrace-gpu: Drop the usemem length check in open_device

nvgrace_gpu_open_device() sets up the fake BAR registers and remap_lock
only when usemem.memlength is nonzero.  The check exists for fallback
mode, which used to share this open path.  Fallback mode now has its own
open_device, so only devices with ACPI memory properties reach this one.

For those devices usemem.memlength is never zero: an empty region from
nvgrace_gpu_fetch_memory_property() selects fallback mode, and probe
fails when nvgrace_gpu_init_nvdev_struct() rounds usemem down to
nothing.  Do the setup unconditionally.

Assisted-by: LLM
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Reviewed-by: Ankit Agrawal <ankita@nvidia.com>
Link: https://lore.kernel.org/r/20261015081937.405320-3-parri.andrea@gmail.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
This commit is contained in:
Andrea Parri 2026-10-15 10:19:35 +02:00 committed by Alex Williamson
parent 9c48b994b6
commit 076d7e989c

View File

@ -188,10 +188,8 @@ static int nvgrace_gpu_open_device(struct vfio_device *core_vdev)
if (ret)
return ret;
if (nvdev->usemem.memlength) {
nvgrace_gpu_init_fake_bar_emu_regs(core_vdev);
mutex_init(&nvdev->remap_lock);
}
nvgrace_gpu_init_fake_bar_emu_regs(core_vdev);
mutex_init(&nvdev->remap_lock);
/*
* GPU readiness is checked by reading the BAR0 registers.