From: Jani Nikula Date: Fri, 5 Sep 2025 10:41:49 +0000 (+0300) Subject: drm/i915/power: fix size for for_each_set_bit() in abox iteration X-Git-Tag: v6.16.8~107 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4b49e9812a29b4ac3fe395bb8f6a755a1bb4f1ca;p=thirdparty%2Fkernel%2Fstable.git drm/i915/power: fix size for for_each_set_bit() in abox iteration commit cfa7b7659757f8d0fc4914429efa90d0d2577dd7 upstream. 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 Cc: Matt Roper Cc: stable@vger.kernel.org # v5.9+ Reviewed-by: Matt Roper Link: https://lore.kernel.org/r/20250905104149.1144751-1-jani.nikula@intel.com Signed-off-by: Jani Nikula (cherry picked from commit 7ea3baa6efe4bb93d11e1c0e6528b1468d7debf6) Signed-off-by: Tvrtko Ursulin Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c index 16356523816fb..068ed911e1245 100644 --- a/drivers/gpu/drm/i915/display/intel_display_power.c +++ b/drivers/gpu/drm/i915/display/intel_display_power.c @@ -1169,7 +1169,7 @@ static void icl_mbus_init(struct intel_display *display) if (DISPLAY_VER(display) == 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(display, MBUS_ABOX_CTL(i), mask, val); } @@ -1630,11 +1630,11 @@ static void tgl_bw_buddy_init(struct intel_display *display) if (table[config].page_mask == 0) { drm_dbg_kms(display->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(display, 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(display, BW_BUDDY_PAGE_MASK(i), table[config].page_mask);