Hi, On Mon, Oct 4, 2021 at 8:42 AM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > > > - if ((edid = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL) > > + edid = (u8 *)drm_do_get_edid_base_block(get_edid_block, data, > > + &connector->edid_corrupt, > > + &connector->null_edid_counter); > > + if (IS_ERR_OR_NULL(edid)) { > > + if (IS_ERR(edid)) > > So edid is an error code, not a valid pointer... > > > + connector_bad_edid(connector, edid, 1); > > ... while connector_bad_edid() expects edid to be a valid pointer, > causing a crash: > > Unable to handle kernel NULL pointer dereference at virtual address Sigh. Thanks for the report and analysis. I guess I don't have any displays reporting invalid EDIDs to test with. Hopefully this will help: https://lore.kernel.org/r/20211004092100.1.Ic90a5ebd44c75db963112be167a03cc96f9fb249@changeid/ -Doug