6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jani Nikula jani.nikula@intel.com
[ Upstream commit cfa7b7659757f8d0fc4914429efa90d0d2577dd7 ]
for_each_set_bit() expects size to be in bits, not bytes. The abox mask iteration uses bytes, but it works by coincidence, because the local variable holding the mask is unsigned long, and the mask only ever has bit 2 as the highest bit. Using a smaller type could lead to subtle and very hard to track bugs.
Fixes: 62afef2811e4 ("drm/i915/rkl: RKL uses ABOX0 for pixel transfers") Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Matt Roper matthew.d.roper@intel.com Cc: stable@vger.kernel.org # v5.9+ Reviewed-by: Matt Roper matthew.d.roper@intel.com Link: https://lore.kernel.org/r/20250905104149.1144751-1-jani.nikula@intel.com Signed-off-by: Jani Nikula jani.nikula@intel.com (cherry picked from commit 7ea3baa6efe4bb93d11e1c0e6528b1468d7debf6) Signed-off-by: Tvrtko Ursulin tursulin@ursulin.net [ adapted struct intel_display *display parameters to struct drm_i915_private *dev_priv ] Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/display/intel_display_power.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/i915/display/intel_display_power.c +++ b/drivers/gpu/drm/i915/display/intel_display_power.c @@ -1170,7 +1170,7 @@ static void icl_mbus_init(struct drm_i91 if (DISPLAY_VER(dev_priv) == 12) abox_regs |= BIT(0);
- for_each_set_bit(i, &abox_regs, sizeof(abox_regs)) + for_each_set_bit(i, &abox_regs, BITS_PER_TYPE(abox_regs)) intel_de_rmw(dev_priv, MBUS_ABOX_CTL(i), mask, val); }
@@ -1623,11 +1623,11 @@ static void tgl_bw_buddy_init(struct drm if (table[config].page_mask == 0) { drm_dbg(&dev_priv->drm, "Unknown memory configuration; disabling address buddy logic.\n"); - for_each_set_bit(i, &abox_mask, sizeof(abox_mask)) + for_each_set_bit(i, &abox_mask, BITS_PER_TYPE(abox_mask)) intel_de_write(dev_priv, BW_BUDDY_CTL(i), BW_BUDDY_DISABLE); } else { - for_each_set_bit(i, &abox_mask, sizeof(abox_mask)) { + for_each_set_bit(i, &abox_mask, BITS_PER_TYPE(abox_mask)) { intel_de_write(dev_priv, BW_BUDDY_PAGE_MASK(i), table[config].page_mask);