Am Donnerstag, den 30.01.2014, 10:05 -0800 schrieb Andy Lutomirski: > On Thu, Jan 30, 2014 at 2:49 AM, <stef...@seibold.net> wrote: > > diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h > > index 59c6c40..45ba688 100644 > > --- a/arch/x86/include/asm/compat.h > > +++ b/arch/x86/include/asm/compat.h > > @@ -295,6 +295,10 @@ static inline compat_uptr_t ptr_to_compat(void __user > > *uptr) > > > > static inline void __user *arch_compat_alloc_user_space(long len) > > { > > +#ifdef CONFIG_X86_32 > > + struct pt_regs *regs = task_pt_regs(current); > > + return (void __user *)regs->sp - len; > > Is there some reason this doesn't need to be aligned? >
The reason is that this function will not used for 32 bit kernels, but will the header will be included... This prevents an error! > > +#else > > compat_uptr_t sp; > > > > if (test_thread_flag(TIF_IA32)) { > > @@ -305,6 +309,7 @@ static inline void __user > > *arch_compat_alloc_user_space(long len) > > } > > > > return (void __user *)round_down(sp - len, 16); > > +#endif > > } > > > > +#define CREATE_TRACE_POINTS > > +#include "vsyscall_trace.h" > > + > > +void __init map_vsyscall(void) > > +{ > > + extern char __vvar_page; > > + unsigned long physaddr_vvar_page = __pa_symbol(&__vvar_page); > > + > > + __set_fixmap(VVAR_PAGE, physaddr_vvar_page, PAGE_KERNEL_VVAR); > > Given that the compat version of this can't (I assume) use a fixmap, > is there any good reason to not just use the same vma-based code for > compat and real 32-bit kernels? > The reason is compability! And it saves two Pages of logical address space wenn using not the VMA compat mode. BTW: It would be a great thing if you would not send back the hole patch. If is very hard to find your replies in tons of line! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/