Hello! This is an experimental semi-automated report about issues detected by Coverity from a scan of next-20221118 as part of the linux-next scan project: https://scan.coverity.com/projects/linux-next-weekly-scan You're getting this email because you were associated with the identified lines of code (noted below) that were touched by commits: Thu Nov 17 16:12:56 2022 +0200 62749912540b ("drm/i915/display: move hti under display sub-struct") Coverity reported the following: *** CID 1527374: Integer handling issues (BAD_SHIFT) drivers/gpu/drm/i915/display/intel_hti.c:24 in intel_hti_uses_phy() 18 if (INTEL_INFO(i915)->display.has_hti) 19 i915->display.hti.state = intel_de_read(i915, HDPORT_STATE); 20 } 21 22 bool intel_hti_uses_phy(struct drm_i915_private *i915, enum phy phy) 23 { vvv CID 1527374: Integer handling issues (BAD_SHIFT) vvv In expression "1UL << 2 * phy + 1", shifting by a negative amount has undefined behavior. The shift amount, "2 * phy + 1", is as little as -1. 24 return i915->display.hti.state & HDPORT_ENABLED && 25 i915->display.hti.state & HDPORT_DDI_USED(phy); 26 } 27 28 u32 intel_hti_dpll_mask(struct drm_i915_private *i915) 29 { If this is a false positive, please let us know so we can mark it as such, or teach the Coverity rules to be smarter. If not, please make sure fixes get into linux-next. :) For patches fixing this, please include these lines (but double-check the "Fixes" first): Reported-by: coverity-bot <keescook+coverity-bot@xxxxxxxxxxxx> Addresses-Coverity-ID: 1527374 ("Integer handling issues") Fixes: 62749912540b ("drm/i915/display: move hti under display sub-struct") This code appears to be safe currently (intel_hti_uses_phy() is never called with PHY_NONE), but perhaps add an explicit check? if (WARN_ON(phy == PHY_NONE)) return false; Thanks for your attention! -- Coverity-bot
