Re: Race conditions in serial_select

[Andrew Lunn <andrew at lunn dot ch>]

On Tue, Jun 21, 2005 at 05:01:29PM +0200, Gaer, A. wrote:
> Hello!
> 
> As the DSR IMHO shouldn't try to accquire the mutex lock anyway, I would
> guess that it is save to do the locking in the proposed way. But I must
> admit that I intended to do it exactly the other way around like it was done
> in all the other functions of the serial.c file, simply to keep the logic a
> bit consistent. Don't ask me why I got it wrong, I must have been completely
> blind that afternoon. Sorry.
> 
> I can resend the patch with the locks swapped, if this is wanted.
> 
> As I understand it, the mutex lock is used to synchronize access to the
> read/write buffers from concurrent threads. As the logic of the select
> depends on the consitency of the buffers during it's exectution, I would say
> the mutex lock is neccessary. Though I can't imagine any usecase where the
> serial select and read/write calls are placed into different threads - but
> who knows.

How does the attacted patch look?

        Andrew

Attachment: io.serial.common.diff
Description: Text document