When userspace takes drm_master, the drm_client buffer is no more visible, so drm_log shouldn't waste CPU cycle to draw on it. Signed-off-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx> --- drivers/gpu/drm/drm_log.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_log.c b/drivers/gpu/drm/drm_log.c index 376ee173d99d9..226e206e8b6a3 100644 --- a/drivers/gpu/drm/drm_log.c +++ b/drivers/gpu/drm/drm_log.c @@ -18,6 +18,7 @@ #include <drm/drm_print.h> #include "drm_draw.h" +#include "drm_internal.h" #include "drm_log.h" MODULE_AUTHOR("Jocelyn Falempe"); @@ -308,8 +309,13 @@ static void drm_log_write_thread(struct console *con, struct nbcon_write_context if (!dlog->probed) drm_log_init_client(dlog); - for (i = 0; i < dlog->n_scanout; i++) - drm_log_draw_kmsg_record(&dlog->scanout[i], wctxt->outbuf, wctxt->len); + /* Check that we are still the master before drawing */ + if (drm_master_internal_acquire(dlog->client.dev)) { + drm_master_internal_release(dlog->client.dev); + + for (i = 0; i < dlog->n_scanout; i++) + drm_log_draw_kmsg_record(&dlog->scanout[i], wctxt->outbuf, wctxt->len); + } } static void drm_log_lock(struct console *con, unsigned long *flags) -- 2.47.0