On 14/06/18 08:57, Zhouyang Jia wrote:
Hi,
I reported this bug since more than 90% callsites of vmap are
well handled in kernel. The caller function __comedi_buf_alloc
has no return value, so I don't know how the error is handled in
its caller.
I believe there would be a better error handling method, but I
have limited domain knowledge, so I'm sorry I can't help here.
Thanks for your kind reply.
Best,
Zhouyang
__comedi_buf_alloc is just a helper function factored out of, and called
by comedi_buf_alloc. __comedi_buf_alloc does not clean up after itself
on error because it expects comedi_buf_alloc to detect the error and
call __comedi_buf_free to clean up any partially allocated mess:
__comedi_buf_alloc(dev, s, n_pages);
if (!async->prealloc_buf) {
/*
* [This is not the actual comment in the code!]
*
* Error occured in __comedi_buf_alloc().
* Buffer may be partially allocated.
* Call __comedi_buf_free() to clean it up.
*/
__comedi_buf_free(dev, s);
return -ENOMEM;
}
2018-06-12 19:50 GMT+08:00 Dan Carpenter <dan.carpenter@xxxxxxxxxx
<mailto:dan.carpenter@xxxxxxxxxx>>:
On Tue, Jun 12, 2018 at 11:25:35AM +0800, Zhouyang Jia wrote:
> When vmap fails, the lack of error-handling code may
> cause unexpected results.
>
> This patch adds error-handling code after calling vmap.
>
Again, this is not error handling, this is just an error message. This
error condition is handled in the caller.
regards,
dan carpenter
--
-=( Ian Abbott <abbotti@xxxxxxxxx> || Web: www.mev.co.uk )=-
-=( MEV Ltd. is a company registered in England & Wales. )=-
-=( Registered number: 02862268. Registered address: )=-
-=( 15 West Park Road, Bramhall, STOCKPORT, SK7 3JZ, UK. )=-
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel