Re: [Qemu-devel] [PATCH 1/2] vl: Fix the confused logic for '-m' option

[zhanghailiang]

On 2014/9/12 21:52, Igor Mammedov wrote:
> On Fri, 12 Sep 2014 13:58:55 +0800
> zhanghailiang<address@hidden>  wrote:
>
> > It should be valid for the follow configure:
> > -m 256,slots=0
> > -m 256,maxmem=256M
> Doc comment/help says that slots&  maxmem must be in pair so above is not valid 
> CLI
> "

Hmm, yes, you are right;), Sorry for the noise.

> -m[emory] [size=]megs[,slots=n,maxmem=size]
>                  configure guest RAM
>                  size: initial amount of guest memory (default: 128MiB)
>                  slots: number of hotplug slots (default: none)
>                  maxmem: maximum amount of guest memory (default: none)
> "
>
> > -m 256,slots=0,maxmem=256M
> > -m 256,slots=x,maxmem=y  where x>  0 and y>  256M
> s/-m 256,slots=x,maxmem=y  where x>  0 and y>  256M/-m z,slots=x,maxmem=y  where 
> x>  0 and y>  z(M)
>
> > Fix the confused code logic and use error_report instead of fprintf.
> >
> > Printing the maxmem in hex, same with ram_size.
> >
> > Signed-off-by: zhanghailiang<address@hidden>
> > ---
> >   vl.c | 46 +++++++++++++++++++++++++++-------------------
> >   1 file changed, 27 insertions(+), 19 deletions(-)
> >
> > diff --git a/vl.c b/vl.c
> > index 9c9acf5..f547405 100644
> > --- a/vl.c
> > +++ b/vl.c
> > @@ -3306,6 +3306,7 @@ int main(int argc, char **argv, char **envp)
> >                   break;
> >               case QEMU_OPTION_m: {
> >                   uint64_t sz;
> > +                uint64_t slots;
> >                   const char *mem_str;
> >                   const char *maxmem_str, *slots_str;
> >
> > @@ -3353,40 +3354,47 @@ int main(int argc, char **argv, char **envp)
> >
> >                   maxmem_str = qemu_opt_get(opts, "maxmem");
> >                   slots_str = qemu_opt_get(opts, "slots");
> > -                if (maxmem_str&&  slots_str) {
> > -                    uint64_t slots;
> > -
> > +                if (maxmem_str) {
> >                       sz = qemu_opt_get_size(opts, "maxmem", 0);
> > +                }
> > +                if (slots_str) {
> > +                    slots = qemu_opt_get_number(opts, "slots", 0);
> > +                }
> > +                if (maxmem_str&&  slots_str) {
> >                       if (sz<  ram_size) {
> > -                        fprintf(stderr, "qemu: invalid -m option value: maxmem 
> > "
> > -                                "(%" PRIu64 ")<= initial memory ("
> > +                        error_report("qemu: invalid -m option value: maxmem "
> > +                                "(%" PRIx64 ")<  initial memory ("
> it may be worth to add 0x before hex number,
> maybe printing maxmem_str instead of number here would be better, since
> user would able to match easily maxmem value and what is printed in error 
> message.

Good idea, will fix it.

> >                                   RAM_ADDR_FMT ")\n", sz, ram_size);
> >                           exit(EXIT_FAILURE);
> >                       }
> > -
> > -                    slots = qemu_opt_get_number(opts, "slots", 0);
> > -                    if ((sz>  ram_size)&&  !slots) {
> > -                        fprintf(stderr, "qemu: invalid -m option value: maxmem 
> > "
> > -                                "(%" PRIu64 ") more than initial memory ("
> > +                    if (!slots&&  (sz != ram_size)) {
> it would report wrong message in case of "-m 256,slots=0,maxmem=128M"

No, in this case, actually it will go into the above *if (sz<  ram_size) {*
branch statements and reports "qemu: invalid -m option value:
maxmem (8000000) < initial memory (10000000)":)


> > +                        error_report("qemu: invalid -m option value: maxmem "
> > +                                "(%" PRIx64 ") more than initial memory ("
> >                                   RAM_ADDR_FMT ") but no hotplug slots where "
> >                                   "specified\n", sz, ram_size);
> >                           exit(EXIT_FAILURE);
> >                       }
> > -
> > -                    if ((sz<= ram_size)&&  slots) {
> > -                        fprintf(stderr, "qemu: invalid -m option value:  %"
> > +                    if (slots&&  (sz == ram_size)) {
> What takes care about the case "-m 256,slots=1,maxmem=128M"?

Same with the above explain.

> > +                        error_report("qemu: invalid -m option value:  %"
> >                                   PRIu64 " hotplug slots where specified but "
> > -                                "maxmem (%" PRIu64 ")<= initial memory ("
> > +                                "maxmem (%" PRIx64 ") = initial memory ("
> >                                   RAM_ADDR_FMT ")\n", slots, sz, ram_size);
> >                           exit(EXIT_FAILURE);
> >                       }
> >                       maxram_size = sz;
> >                       ram_slots = slots;
> > -                } else if ((!maxmem_str&&  slots_str) ||
> > -                           (maxmem_str&&  !slots_str)) {
> > -                    fprintf(stderr, "qemu: invalid -m option value: missing "
> > -                            "'%s' option\n", slots_str ? "maxmem" : "slots");
> > -                    exit(EXIT_FAILURE);
> > +                } else if (!maxmem_str&&  slots_str) {
> > +                    if (slots>  0) {
> > +                        error_report("qemu: invalid -m option value: missing "
> > +                                "'maxmem' option\n");
> > +                        exit(EXIT_FAILURE);
> > +                    }
> > +                } else if (maxmem_str&&  !slots_str) {
> > +                    if (sz != ram_size) {
> > +                        error_report("qemu: invalid -m option value: missing "
> > +                                "'slot' option\n");
> > +                        exit(EXIT_FAILURE);
> > +                    }
> >                   }
> >                   break;
> >               }
>
>
> .