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Date:   Wed, 16 Nov 2022 16:17:37 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Marco Pagani <marpagan@redhat.com>
Cc:     Oded Gabbay <ogabbay@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev
Subject: Re: [PATCH] habanalabs: added return value check for
 hl_fw_dynamic_send_clear_cmd()
Message-ID: <Y3T/ESXEb+MF2QEW@kroah.com>
References: <20221116134126.199087-1-marpagan@redhat.com>
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On Wed, Nov 16, 2022 at 02:41:25PM +0100, Marco Pagani wrote:
> The clang-analyzer reported a warning: "Value stored to 'rc' is never
> read".
> 
> The return value check for the first hl_fw_dynamic_send_clear_cmd() call
> in hl_fw_dynamic_send_protocol_cmd() appears to be missing.
> 
> Signed-off-by: Marco Pagani <marpagan@redhat.com>
> ---
>  drivers/misc/habanalabs/common/firmware_if.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/misc/habanalabs/common/firmware_if.c b/drivers/misc/habanalabs/common/firmware_if.c
> index 2de6a9bd564d..311942108dbc 100644
> --- a/drivers/misc/habanalabs/common/firmware_if.c
> +++ b/drivers/misc/habanalabs/common/firmware_if.c
> @@ -1782,6 +1782,8 @@ int hl_fw_dynamic_send_protocol_cmd(struct hl_device *hdev,
>  
>  	/* first send clear command to clean former commands */
>  	rc = hl_fw_dynamic_send_clear_cmd(hdev, fw_loader);
> +	if (rc)
> +		return rc;
>  
>  	/* send the actual command */
>  	hl_fw_dynamic_send_cmd(hdev, fw_loader, cmd, size);

Are you sure this is ok?  If the first "clean the buffer" command fails,
all should still be good as that wasn't the real command.

But maybe the hardware will never fail this?

thanks,

greg k-h