Re: [Qemu-devel] [PATCH 01/10] crypto: introduce new module for computing hash digests

[Daniel P. Berrange]

On Tue, Jun 02, 2015 at 09:43:18AM +0200, Markus Armbruster wrote:
> "Daniel P. Berrange" <address@hidden> writes:
> 
> > On Thu, May 28, 2015 at 09:28:20PM +0800, Gonglei wrote:
> >> On 2015/5/21 18:56, Daniel P. Berrange wrote:
> >> > Introduce a new crypto/ directory that will (eventually) contain
> >> > all the cryptographic related code. This initially defines a
> >> > wrapper for initializing gnutls and for computing hashes with
> >> > gnutls. The former ensures that gnutls is guaranteed to be
> >> > initialized exactly once in QEMU regardless of CLI args. The
> >> > block quorum code currently fails to initialize gnutls so it
> >> > only works by luck, if VNC server TLS is not requested. The
> >> > hash APIs avoids the need to litter the rest of the code with
> >> > preprocessor checks and simplifies callers by allocating the
> >> > correct amount of memory for the requested hash.
> >> > 
> >> > Signed-off-by: Daniel P. Berrange <address@hidden>
> [...]
> >> > diff --git a/vl.c b/vl.c
> >> > index 15bccc4..72313a4 100644
> >> > --- a/vl.c
> >> > +++ b/vl.c
> >> > @@ -119,6 +119,7 @@ int main(int argc, char **argv)
> >> >  #include "qapi/opts-visitor.h"
> >> >  #include "qom/object_interfaces.h"
> >> >  #include "qapi-event.h"
> >> > +#include "crypto/init.h"
> >> >  
> >> >  #define DEFAULT_RAM_SIZE 128
> >> >  
> >> > @@ -2777,6 +2778,7 @@ int main(int argc, char **argv, char **envp)
> >> >      uint64_t ram_slots = 0;
> >> >      FILE *vmstate_dump_file = NULL;
> >> >      Error *main_loop_err = NULL;
> >> > +    Error *err = NULL;
> >> >  
> >> >      qemu_init_cpu_loop();
> >> >      qemu_mutex_lock_iothread();
> >> > @@ -2819,6 +2821,12 @@ int main(int argc, char **argv, char **envp)
> >> >  
> >> >      runstate_init();
> >> >  
> >> > +    if (qcrypto_init(&err) < 0) {
> >> > +        fprintf(stderr, "Cannot initialize crypto: %s\n",
> >> > +                error_get_pretty(err));
> >> > +        error_free(err);
> >> 
> >> This free is superflous (before exit) IMO.
> >
> > Personally I always free variables like this so valgrind doesn't complain
> > about leaks.
> 
> Marginally useful when you do it for the complete program.  QEMU
> doesn't, and making all of QEMU do it would be a fool's errand.

Ok, i'll remove it.

Regards,
Daniel
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