2016-03-17 08:13:06

by Jandy Gou

[permalink] [raw]
Subject: [PATCH] staging: r8723au: This patch tries to fix some byte order issues that is found by sparse check.

make C=1 M=drivers/staging/rtl8723au/

drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:96:38: warning: cast to
restricted __le16
drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:100:27: warning: cast to
restricted __le32

Signed-off-by: Jandy Gou <[email protected]>
---
drivers/staging/rtl8723au/hal/rtl8723a_cmd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c b/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
index 1662c03c..d82fd8a 100644
--- a/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
+++ b/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
@@ -93,11 +93,11 @@ int FillH2CCmd(struct rtw_adapter *padapter, u8 ElementID, u32 CmdLen,

if (h2c_cmd & BIT(7)) {
msgbox_ex_addr = REG_HMEBOX_EXT_0 + (h2c_box_num * EX_MESSAGE_BOX_SIZE);
- h2c_cmd_ex = le16_to_cpu(h2c_cmd_ex);
+ le16_to_cpus(&h2c_cmd_ex);
rtl8723au_write16(padapter, msgbox_ex_addr, h2c_cmd_ex);
}
msgbox_addr = REG_HMEBOX_0 + (h2c_box_num * MESSAGE_BOX_SIZE);
- h2c_cmd = le32_to_cpu(h2c_cmd);
+ le32_to_cpus(&h2c_cmd);
rtl8723au_write32(padapter, msgbox_addr, h2c_cmd);

bcmd_down = true;
--
1.9.1



2016-03-17 09:19:22

by Julian Calaby

[permalink] [raw]
Subject: Re: [PATCH] staging: r8723au: This patch tries to fix some byte order issues that is found by sparse check.

Hi Jandy,

On Thu, Mar 17, 2016 at 7:03 PM, Jandy Gou <[email protected]> wrote:
> make C=1 M=drivers/staging/rtl8723au/
>
> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:96:38: warning: cast to
> restricted __le16
> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:100:27: warning: cast to
> restricted __le32
>
> Signed-off-by: Jandy Gou <[email protected]>

I'm not sure your change is correct. Perhaps you should add temporary
variables for h2c_cmd_ex and h2c_cmd while they're cpu-endian?

Jes,

I'm pretty sure this isn't the first time this has come up. Do you
have any ideas for a solution? Or should we ignore this as this driver
will eventually be going away?

Thanks,

Julian Calaby

> ---
> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c b/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
> index 1662c03c..d82fd8a 100644
> --- a/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
> +++ b/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
> @@ -93,11 +93,11 @@ int FillH2CCmd(struct rtw_adapter *padapter, u8 ElementID, u32 CmdLen,
>
> if (h2c_cmd & BIT(7)) {
> msgbox_ex_addr = REG_HMEBOX_EXT_0 + (h2c_box_num * EX_MESSAGE_BOX_SIZE);
> - h2c_cmd_ex = le16_to_cpu(h2c_cmd_ex);
> + le16_to_cpus(&h2c_cmd_ex);
> rtl8723au_write16(padapter, msgbox_ex_addr, h2c_cmd_ex);
> }
> msgbox_addr = REG_HMEBOX_0 + (h2c_box_num * MESSAGE_BOX_SIZE);
> - h2c_cmd = le32_to_cpu(h2c_cmd);
> + le32_to_cpus(&h2c_cmd);
> rtl8723au_write32(padapter, msgbox_addr, h2c_cmd);
>
> bcmd_down = true;
> --
> 1.9.1
>
>
> --
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--
Julian Calaby

Email: [email protected]
Profile: http://www.google.com/profiles/julian.calaby/

2016-03-17 14:39:20

by Jes Sorensen

[permalink] [raw]
Subject: Re: [PATCH] staging: r8723au: This patch tries to fix some byte order issues that is found by sparse check.

Jandy Gou <[email protected]> writes:
> make C=1 M=drivers/staging/rtl8723au/
>
> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:96:38: warning: cast to
> restricted __le16
> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:100:27: warning: cast to
> restricted __le32
>
> Signed-off-by: Jandy Gou <[email protected]>
> ---
> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c b/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
> index 1662c03c..d82fd8a 100644
> --- a/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
> +++ b/drivers/staging/rtl8723au/hal/rtl8723a_cmd.c
> @@ -93,11 +93,11 @@ int FillH2CCmd(struct rtw_adapter *padapter, u8 ElementID, u32 CmdLen,
>
> if (h2c_cmd & BIT(7)) {
> msgbox_ex_addr = REG_HMEBOX_EXT_0 + (h2c_box_num * EX_MESSAGE_BOX_SIZE);
> - h2c_cmd_ex = le16_to_cpu(h2c_cmd_ex);
> + le16_to_cpus(&h2c_cmd_ex);
> rtl8723au_write16(padapter, msgbox_ex_addr, h2c_cmd_ex);
> }
> msgbox_addr = REG_HMEBOX_0 + (h2c_box_num * MESSAGE_BOX_SIZE);
> - h2c_cmd = le32_to_cpu(h2c_cmd);
> + le32_to_cpus(&h2c_cmd);
> rtl8723au_write32(padapter, msgbox_addr, h2c_cmd);

Please do *not* use le{16,32}_to_cpus() that is so gross it's hard to
even put words on it. Use a temp variable of the correct type instead.

NAK

Jes

2016-03-17 14:44:27

by Jes Sorensen

[permalink] [raw]
Subject: Re: [PATCH] staging: r8723au: This patch tries to fix some byte order issues that is found by sparse check.

Julian Calaby <[email protected]> writes:
> Hi Jandy,
>
> On Thu, Mar 17, 2016 at 7:03 PM, Jandy Gou <[email protected]> wrote:
>> make C=1 M=drivers/staging/rtl8723au/
>>
>> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:96:38: warning: cast to
>> restricted __le16
>> drivers/staging/rtl8723au/hal/rtl8723a_cmd.c:100:27: warning: cast to
>> restricted __le32
>>
>> Signed-off-by: Jandy Gou <[email protected]>
>
> I'm not sure your change is correct. Perhaps you should add temporary
> variables for h2c_cmd_ex and h2c_cmd while they're cpu-endian?
>
> Jes,
>
> I'm pretty sure this isn't the first time this has come up. Do you
> have any ideas for a solution? Or should we ignore this as this driver
> will eventually be going away?

Temp variables as you suggest would be a clean way to accomplish this.

Technically this might work, but esthetically this is so gross I wish I
had never seen it. There is a reason why we have the byteorder specific
types, and le{16,32}_to_cpus() violates that.

I am surprised we still have these macros around, tbh I didn't even know
they existed. A quick search for le16_to_cpus() shows that it's really
very old drivers and some more recent Intel Ethernet drivers that use
them - maybe this would be a good time to get rid of them completely.

Cheers,
Jes