Subject: Re: linux-next: build failure after merge of the drm tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 6 Oct 2022 19:12:45 +1100

Hi all,

On Thu, 6 Oct 2022 09:28:10 +1100 Stephen Rothwell <[email-masked]> wrote:
>
> I have applied the following hack for today:
> 
> From: Stephen Rothwell <[email-masked]>
> Date: Thu, 6 Oct 2022 09:14:26 +1100
> Subject: [PATCH] fix up for drivers/gpu/drm/amd/display/dc/core/dc_stream.c
> 
> Signed-off-by: Stephen Rothwell <[email-masked]>
> ---
>  drivers/gpu/drm/amd/display/dc/core/dc_stream.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
> index ae13887756bf..a5da787b7876 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
> @@ -520,9 +520,9 @@ bool dc_stream_remove_writeback(struct dc *dc,
>  	}
>  
>  	/* remove writeback info for disabled writeback pipes from stream */
> -	for (i = 0, j = 0; i < stream->num_wb_info && j < MAX_DWB_PIPES; i++) {
> +	for (i = 0, j = 0; i < stream->num_wb_info && i < MAX_DWB_PIPES; i++) {
>  		if (stream->writeback_info[i].wb_enabled) {
> -			if (i != j)
> +			if ((j >= 0) && (j < i))
>  				/* trim the array */
>  				stream->writeback_info[j] = stream->writeback_info[i];
>  			j++;

This works as well, and (in my opinion) is better:

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
index ae13887756bf..fb6222d4c430 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_stream.c
@@ -499,7 +499,7 @@ bool dc_stream_remove_writeback(struct dc *dc,
 		struct dc_stream_state *stream,
 		uint32_t dwb_pipe_inst)
 {
-	int i = 0, j = 0;
+	unsigned int i, j;
 	if (stream == NULL) {
 		dm_error("DC: dc_stream is NULL!\n");
 		return false;
@@ -520,9 +520,9 @@ bool dc_stream_remove_writeback(struct dc *dc,
 	}
 
 	/* remove writeback info for disabled writeback pipes from stream */
-	for (i = 0, j = 0; i < stream->num_wb_info && j < MAX_DWB_PIPES; i++) {
+	for (i = 0, j = 0; i < stream->num_wb_info; i++) {
 		if (stream->writeback_info[i].wb_enabled) {
-			if (i != j)
+			if (j < i)
 				/* trim the array */
 				stream->writeback_info[j] = stream->writeback_info[i];
 			j++;

-- 
Cheers,
Stephen Rothwell