drm/msm/dsi: Fix VM leak in dsi_tx_buf_alloc_6g()

dsi_tx_buf_alloc_6g() takes a reference to the kms VM with
drm_gpuvm_get() and stores it in msm_host->vm.  If
msm_gem_kernel_new() fails, the function returns early without
dropping that reference.  Since msm_host->tx_gem_obj is cleared on
the error path, msm_dsi_tx_buf_free() will never see a non-NULL
tx_gem_obj and thus never calls drm_gpuvm_put(), leaking the VM
reference.

Drop the VM reference and clear msm_host->vm on the error path.

Fixes: 5e05be782645 ("drm/msm/dsi: free TX buffer in unbind")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Rob Clark <rob.clark@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/754332/
Link: https://lore.kernel.org/r/20260916175738.2089950-1-vulab@iscas.ac.cn
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

0 files changed, 0 insertions, 0 deletions