> -----Original Message-----
> From: Takashi Iwai <tiwai@xxxxxxx>
> Sent: Friday, November 5, 2021 11:07 PM
> To: Pkshih <pkshih@xxxxxxxxxxx>
> Cc: kvalo@xxxxxxxxxxxxxx; linux-wireless@xxxxxxxxxxxxxxx; Larry.Finger@xxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH] rtw89: Fix crash by loading compressed firmware file
>
>
> You should put const in the cast in le32_get_bits() invocations, at
> least.
>
> For the le32_replace_bits(), ideally it should be rewritten in some
> better way the compiler can catch. e.g. use an inline function to
> take a void * argument without const,
>
> static inline void RTW89_SET_FWCMD_CXRFK_TYPE(void *cmd, unsigned int val)
> {
> le32p_replace_bits((__le32 *)((u8 *)(cmd) + 2), val, GENMASK(17, 10));
> }
>
> Then the compiler will warn when you pass a const pointer there.
>
I have sent a patchset [1] to do these two things by patch 2 and 3.
>
> BTW, while reading your reply, I noticed that it's an unaligned access
> to a 32bit value, which is another potential breakage on some
> architectures. So the whole stuff has to be rewritten in anyway...
>
We use these macros/inline function on skb->data mostly, and I
suppose skb->data is a 32bit aligned address. Since I don't have
this kind of machine on hand, I would like to defer this work until
I have one.
>
> > The macro SET_FW_HDR_PART_SIZE() is used to set the firmware
> > partition size we are going to download, and it is only used
> > by rtw89_fw_download_hdr(). So, I will set the partition size
> > after copying constant firmware header into skb->data.
>
> Sounds good.
>
Please check if my patch works on your platform.
Thanks you.
[1] https://lore.kernel.org/linux-wireless/20211111021457.13776-1-pkshih@xxxxxxxxxxx/T/#t
--
Ping-Ke
