From 33978364a2f3fc2989751bdabcaea0ec7e8d1ae8 Mon Sep 17 00:00:00 2001 From: Jonathan Cavitt Date: Fri, 23 Jan 2026 15:21:22 +0000 Subject: [PATCH] drm/i915/display: PORT_NONE is not valid Static analysis issue: In assert_port_valid, add a check to ensure port != PORT_NONE, as that is not a valid port. The check must be explicit to prevent a bad bit shift operation in the general case via short-circuiting. It's not likely this will ever come up in a real use case, but it's at least worth guarding against. It would probably also be pertinent to modify the behavior of the port_name function to correctly print PORT_NONE in this case, as currently the port would be reported as 'port @' by the debugger. But that should be done separately, and given port_name is mostly just a debug printing helper function anyways, fixing it is a low priority. v2: - Conditional check was backwards. Fix it. (Jani) Signed-off-by: Jonathan Cavitt Cc: Jani Nikula Reviewed-by: Jani Nikula Link: https://patch.msgid.link/20260123152121.7042-2-jonathan.cavitt@intel.com Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_display.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index b18ce0c36a649..ee501009a251f 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -7890,7 +7890,8 @@ static bool intel_ddi_crt_present(struct intel_display *display) bool assert_port_valid(struct intel_display *display, enum port port) { - return !drm_WARN(display->drm, !(DISPLAY_RUNTIME_INFO(display)->port_mask & BIT(port)), + return !drm_WARN(display->drm, + !(port >= 0 && DISPLAY_RUNTIME_INFO(display)->port_mask & BIT(port)), "Platform does not support port %c\n", port_name(port)); } -- 2.47.3