Re: [PATCH] fs/btrfs: Fix uninitialized variable

[Dan Carpenter]

On Mon, May 03, 2021 at 11:13:12AM +0100, Khaled Romdhani wrote:
> On Mon, May 03, 2021 at 10:23:22AM +0300, Dan Carpenter wrote:
> > On Sat, May 01, 2021 at 11:50:46PM +0100, Khaled ROMDHANI wrote:
> > > Fix the warning: variable 'zone' is used
> > > uninitialized whenever '?:' condition is true.
> > > 
> > > Fix that by preventing the code to reach
> > > the last assertion. If the variable 'mirror'
> > > is invalid, the assertion fails and we return
> > > immediately.
> > > 
> > > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > > Signed-off-by: Khaled ROMDHANI <khaledromdhani216@xxxxxxxxx>
> > > ---
> > 
> > This is not how you send a v4 patch...  v2 patches have to apply to the
> > original code and not on top of the patched code.
> > 
> > I sort of think you should find a different thing to work on.  This code
> > works fine as-is.  Just leave it and try to find a real bug and fix that
> > instead.
> > 
> > regards,
> > dan carpenter
> >
> 
> Sorry, I was wrong and I shall send a proper V4.
> 
> Yes, this code works fine just a warning caught by Coverity scan analysis. 

We're going to a lot of work to silence a static checker false positive.
As a rule, I tell people to ignore the static checker when it is wrong.

Btw, Smatch parses this code correctly and understands that the callers
only pass valid values for "mirror".

regards,
dan carpenter