On 2024-07-23 16:51:21+0000, Alex Deucher wrote:
> The comment in the vbios structure says:
> // = 128 means EDID length is 128 bytes, otherwise the EDID length =
> ucFakeEDIDLength*128
>
> This fake edid struct has not been used in a long time, so I'm
> not sure if there were actually any boards out there with a non-128 byte
> EDID, but align the code with the comment.
>
> Reported-by: Thomas Weißschuh <li...@weissschuh.net>
> Link: https://lists.freedesktop.org/archives/amd-gfx/2024-June/109964.html
> Fixes: c324acd5032f ("drm/radeon/kms: parse the extended LCD info block")
> Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Reviewed-by: Thomas Weißschuh <li...@weissschuh.net>
> ---
>
> V2: Incorporate comments.
> Fix accidently dropped hunk.
>
> drivers/gpu/drm/radeon/radeon_atombios.c | 29 +++++++++++++-----------
> 1 file changed, 16 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/radeon/radeon_atombios.c
> b/drivers/gpu/drm/radeon/radeon_atombios.c
> index 97c4e10d0550..168f3f94003b 100644
> --- a/drivers/gpu/drm/radeon/radeon_atombios.c
> +++ b/drivers/gpu/drm/radeon/radeon_atombios.c
> @@ -1717,26 +1717,29 @@ struct radeon_encoder_atom_dig
> *radeon_atombios_get_lvds_info(struct
> fake_edid_record =
> (ATOM_FAKE_EDID_PATCH_RECORD *)record;
> if (fake_edid_record->ucFakeEDIDLength)
> {
> struct edid *edid;
> - int edid_size =
> - max((int)EDID_LENGTH,
> (int)fake_edid_record->ucFakeEDIDLength);
> - edid = kmalloc(edid_size,
> GFP_KERNEL);
> + int edid_size;
> +
> + if
> (fake_edid_record->ucFakeEDIDLength == 128)
> + edid_size =
> fake_edid_record->ucFakeEDIDLength;
> + else
> + edid_size =
> fake_edid_record->ucFakeEDIDLength * 128;
> + edid =
> kmemdup(&fake_edid_record->ucFakeEDIDString[0],
> + edid_size,
> GFP_KERNEL);
> if (edid) {
> - memcpy((u8 *)edid, (u8
> *)&fake_edid_record->ucFakeEDIDString[0],
> -
> fake_edid_record->ucFakeEDIDLength);
> -
> if
> (drm_edid_is_valid(edid)) {
>
> rdev->mode_info.bios_hardcoded_edid = edid;
>
> rdev->mode_info.bios_hardcoded_edid_size = edid_size;
> - } else
> + } else {
> kfree(edid);
> + }
> }
> + record +=
> struct_size(fake_edid_record,
> +
> ucFakeEDIDString,
> +
> edid_size);
> + } else {
> + /* empty fake edid record must
> be 3 bytes long */
> + record +=
> sizeof(ATOM_FAKE_EDID_PATCH_RECORD) + 1;
> }
> - record +=
> fake_edid_record->ucFakeEDIDLength ?
> - struct_size(fake_edid_record,
> - ucFakeEDIDString,
> -
> fake_edid_record->ucFakeEDIDLength) :
> - /* empty fake edid record
> must be 3 bytes long */
> -
> sizeof(ATOM_FAKE_EDID_PATCH_RECORD) + 1;
> break;
> case LCD_PANEL_RESOLUTION_RECORD_TYPE:
> panel_res_record =
> (ATOM_PANEL_RESOLUTION_PATCH_RECORD *)record;
> --
> 2.45.2
>
