Jan Kiszka wrote: > [Let's discuss this without bothering users :)] > > Philippe Gerum wrote: > > Author: rpm > > Date: Sun Nov 4 18:18:39 2007 > > New Revision: 3147 > > > > URL: http://svn.gna.org/viewcvs/xenomai?rev=3147&view=rev > > Log: > > Make __xn_access_ok() return false for addresses lower than the natural > > page size. > > > > Modified: > > trunk/ChangeLog > > trunk/include/asm-x86/syscall_32.h > > trunk/include/asm-x86/syscall_64.h > > Could it be that you meant "PAGE_SIZE" instead of "PAGE_OFFSET"? Because > the current version is "slightly" broken, tagging any address in user > land as invalid. > > And if this test was meant to catch NULL page accesses early, is the > intention to cope with all those current i-pipe patches that do not yet > include the discussed domain switch on non-root faults? If yes, this > test would be a workaround for legacy code and should not become default > (pure overhead for later versions).
We can reduce the overhead of the two tests by testing (unsigned long) (addr - PAGE_SIZE) < (PAGE_OFFSET - PAGE_SIZE) > > Last question: We need this for the other archs as well, don't we? > > Jan > > _______________________________________________ > Xenomai-core mailing list > Xenomaifirstname.lastname@example.org > https://mail.gna.org/listinfo/xenomai-core -- Gilles Chanteperdrix. _______________________________________________ Xenomai-core mailing list Xenomaiemail@example.com https://mail.gna.org/listinfo/xenomai-core