Re: [PATCH v2 02/13] block/iscsi:Remove redundant statement in iscsi_open()

[Kevin Wolf]

Am 27.02.2020 um 02:49 hat Chenqun (kuhn) geschrieben:
> >-----Original Message-----
> >From: Kevin Wolf [mailto:address@hidden]
> >Sent: Wednesday, February 26, 2020 5:55 PM
> >To: Chenqun (kuhn) <address@hidden>
> >Cc: address@hidden; address@hidden;
> >address@hidden; Zhanghailiang <address@hidden>;
> >Euler Robot <address@hidden>; Ronnie Sahlberg
> ><address@hidden>; Paolo Bonzini <address@hidden>; Peter
> >Lieven <address@hidden>; Max Reitz <address@hidden>
> >Subject: Re: [PATCH v2 02/13] block/iscsi:Remove redundant statement in
> >iscsi_open()
> >
> >Am 26.02.2020 um 09:46 hat address@hidden geschrieben:
> >> From: Chen Qun <address@hidden>
> >>
> >> Clang static code analyzer show warning:
> >>   block/iscsi.c:1920:9: warning: Value stored to 'flags' is never read
> >>         flags &= ~BDRV_O_RDWR;
> >>         ^        ~~~~~~~~~~~~
> >>
> >> Reported-by: Euler Robot <address@hidden>
> >> Signed-off-by: Chen Qun <address@hidden>
> >
> >Hmm, I'm not so sure about this one because if we remove the line, flags will
> >be inconsistent with bs->open_flags. It feels like setting a trap for anyone
> >who wants to add code using flags in the future.
> Hi Kevin,  
> I find it exists since 8f3bf50d34037266.   :  )  

Yes, it has existed from the start with auto-read-only.

> It's not a big deal,  just upset clang static code analyzer. 
> As you said, it could be a trap for the future. 

What's interesting is that we do have one user of the flags later in the
function, but it uses bs->open_flags instead:

    ret = iscsi_allocmap_init(iscsilun, bs->open_flags);

Maybe this should be using flags? (The value of the bits we're
interested in is the same, but when flags is passed as a parameter, I
would expect it to be used.)

Kevin