Message-ID: <10d91214-4106-7a9d-b1ac-68df1aa5f6c9@quicinc.com>
Date:   Thu, 2 Feb 2023 15:44:45 +0530
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Subject: Re: [PATCH V2] Serial: core: Add compat ioctl support
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To:     Greg KH <gregkh@linuxfoundation.org>
CC:     <jirislaby@kernel.org>, <linux-serial@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <quic_msavaliy@quicinc.com>,
        <quic_vnivarth@quicinc.com>, <quic_vtanuku@quicinc.com>,
        <quic_arandive@quicinc.com>
References: <20230125113418.7221-1-quic_vdadhani@quicinc.com>
 <Y9EfYCBngFAG+RBw@kroah.com>
From:   Viken Dadhaniya <quic_vdadhani@quicinc.com>
In-Reply-To: <Y9EfYCBngFAG+RBw@kroah.com>
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Hi Greg,

"Can you point us at the out-of-tree code please?"

Please refer: 
https://git.codelinaro.org/clo/la/kernel/msm-5.10/-/blob/KERNEL.PLATFORM.1.0.r3-01300-kernel.0/drivers/tty/serial/msm_geni_serial.c#L750

Thanks

Viken Dadhaniya


On 1/25/2023 5:54 PM, Greg KH wrote:
> On Wed, Jan 25, 2023 at 05:04:18PM +0530, Viken Dadhaniya wrote:
>> Current serial core driver doesn't support compat_ioctl
>> due to which 32-bit application is not able to send
>> ioctls to driver on a 64-bit platform.
>>
>> Added compat_ioctl support in serial core to handle
>> ioctls from 32-bit applications on a 64-bit platform.
>>
>> Signed-off-by: Viken Dadhaniya <quic_vdadhani@quicinc.com>
>> ---
>>   drivers/tty/serial/serial_core.c | 7 +++++++
>>   1 file changed, 7 insertions(+)
>>
>> diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
>> index b9fbbee598b8..ad4c3a5a3d29 100644
>> --- a/drivers/tty/serial/serial_core.c
>> +++ b/drivers/tty/serial/serial_core.c
>> @@ -1601,6 +1601,12 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
>>   	return ret;
>>   }
>>   
>> +static long
>> +uart_compat_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
>> +{
>> +	return (long)uart_ioctl(tty, cmd, arg);
> How does this "fix" your out-of-tree driver at all?  What command is
> being sent that has this incorrect that this simple "pass through" is
> going to solve?
>
> Can you point us at the out-of-tree code please?
>
> thanks,
>
> greg k-h