2021-08-28 15:42:48

by F.A.Sulaiman

Subject: [PATCH] GPU:drm: returning ENOMEM

When memory allocation is failed this patch returns out of memory error instead of -1.

Signed-off-by: F.A. SULAIMAN <[email protected]>
---
drivers/gpu/drm/udl/udl_connector.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/udl/udl_connector.c b/drivers/gpu/drm/udl/udl_connector.c
index 3750fd216131..afebab6186ab 100644
--- a/drivers/gpu/drm/udl/udl_connector.c
+++ b/drivers/gpu/drm/udl/udl_connector.c
@@ -24,7 +24,7 @@ static int udl_get_edid_block(void *data, u8 *buf, unsigned int block,

read_buff = kmalloc(2, GFP_KERNEL);
if (!read_buff)
- return -1;
+ return -ENOMEM;

for (i = 0; i < len; i++) {
int bval = (i + block * EDID_LENGTH) << 8;
--
2.17.1

2021-08-30 16:04:54

by F.A.Sulaiman

Subject: [PATCH v2] GPU:DRM: returning ENOMEM

check the return value and pass the proper error code.

Signed-off-by: F.A. SULAIMAN <[email protected]>
---
drivers/gpu/drm/udl/udl_connector.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_connector.c b/drivers/gpu/drm/udl/udl_connector.c
index cdc1c42e1669..857d2c97ef0e 100644
--- a/drivers/gpu/drm/udl/udl_connector.c
+++ b/drivers/gpu/drm/udl/udl_connector.c
@@ -23,7 +23,7 @@ static int udl_get_edid_block(void *data, u8 *buf, unsigned int block,

read_buff = kmalloc(2, GFP_KERNEL);
if (!read_buff)
- return -1;
+ return -ENOMEM;

for (i = 0; i < len; i++) {
int bval = (i + block * EDID_LENGTH) << 8;
@@ -31,11 +31,16 @@ static int udl_get_edid_block(void *data, u8 *buf, unsigned int block,
usb_rcvctrlpipe(udl->udev, 0),
(0x02), (0x80 | (0x02 << 5)), bval,
0xA1, read_buff, 2, HZ);
- if (ret < 1) {
+ if (ret == 0) {
+ DRM_ERROR("Reading EDID block %d returned empty result\n", i);
+ kfree(read_buff);
+ return -EINVAL;
+ } else if (ret < 0) {
DRM_ERROR("Read EDID byte %d failed err %x\n", i, ret);
kfree(read_buff);
- return -1;
+ return ret;
}
+
buf[i] = read_buff[1];
}

--
2.17.1

2021-08-30 16:09:49

by Simon Ser

Subject: Re: [PATCH v2] GPU:DRM: returning ENOMEM

Maybe the commit message can be improved a bit? Add a prefix to make it
clear this is about the udl driver, make it clear this is about the
udl_get_edid_block function. The new `return ret` statement may return
something different from ENOMEM.

This would give something among these lines:

drm/udl: return -errno in udl_get_edid_block