| Message ID | 200908260137.48781.dl9pf@gmx.de |
|---|---|
| State | Superseded |
| Headers | show |
On Wed, Aug 26, 2009 at 01:37:48AM +0200, Jan-Simon Möller wrote: > Thinking a bit more about this, I wonder if g2h(x) shouldn't itself always > return NULL on x = NULL ? I agree this seems like a a better idea than modifying the users of g2h. > Something like: > > Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> > > diff --git a/cpu-all.h b/cpu-all.h > index 1a6a812..631f678 100644 > --- a/cpu-all.h > +++ b/cpu-all.h > @@ -633,7 +633,7 @@ extern int have_guest_base; > #endif > > /* All direct uses of g2h and h2g need to go away for usermode softmmu. */ > -#define g2h(x) ((void *)((unsigned long)(x) + GUEST_BASE)) > +#define g2h(x) ( !x ? NULL:((void *)((unsigned long)(x) + GUEST_BASE))) > #define h2g(x) ({ \ > unsigned long __ret = (unsigned long)(x) - GUEST_BASE; \ > /* Check if given address fits target address space */ \ > > > I read the comment above, but before replacing it in user-mode (if possible), > we should fix it ;) . > > > Best, > Jan-Simon > > >
Am Mittwoch 26 August 2009 15:40:43 schrieb Riku Voipio: > On Wed, Aug 26, 2009 at 01:37:48AM +0200, Jan-Simon Möller wrote: > > Thinking a bit more about this, I wonder if g2h(x) shouldn't itself > > always return NULL on x = NULL ? > > I agree this seems like a a better idea than modifying the users of g2h. > Ok, then please apply to master. Best, Jan-Simon
Am Mittwoch 26 August 2009 15:40:43 schrieb Riku Voipio: > On Wed, Aug 26, 2009 at 01:37:48AM +0200, Jan-Simon Möller wrote: > > Thinking a bit more about this, I wonder if g2h(x) shouldn't itself > > always return NULL on x = NULL ? > > I agree this seems like a a better idea than modifying the users of g2h. > > > Something like: > > > > Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> > > > > diff --git a/cpu-all.h b/cpu-all.h > > index 1a6a812..631f678 100644 > > --- a/cpu-all.h > > +++ b/cpu-all.h > > @@ -633,7 +633,7 @@ extern int have_guest_base; > > #endif > > > > /* All direct uses of g2h and h2g need to go away for usermode softmmu. > > */ -#define g2h(x) ((void *)((unsigned long)(x) + GUEST_BASE)) > > +#define g2h(x) ( !x ? NULL:((void *)((unsigned long)(x) + GUEST_BASE))) > > #define h2g(x) ({ \ > > unsigned long __ret = (unsigned long)(x) - GUEST_BASE; \ > > /* Check if given address fits target address space */ \ > > > > Take the first patch for syscall.c / mount . Unfortunately, the above one has side-effects where functions rely on a shifted NULL pointer ... Best, Jan-Simon
diff --git a/cpu-all.h b/cpu-all.h index 1a6a812..631f678 100644 --- a/cpu-all.h +++ b/cpu-all.h @@ -633,7 +633,7 @@ extern int have_guest_base; #endif /* All direct uses of g2h and h2g need to go away for usermode softmmu. */ -#define g2h(x) ((void *)((unsigned long)(x) + GUEST_BASE)) +#define g2h(x) ( !x ? NULL:((void *)((unsigned long)(x) + GUEST_BASE))) #define h2g(x) ({ \ unsigned long __ret = (unsigned long)(x) - GUEST_BASE; \ /* Check if given address fits target address space */ \
Thinking a bit more about this, I wonder if g2h(x) shouldn't itself always return NULL on x = NULL ? Something like: Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> I read the comment above, but before replacing it in user-mode (if possible), we should fix it ;) . Best, Jan-Simon