On Fri, Jul 08, 2011 at 12:21:27AM +0100, David Gilbert wrote: > On 5 July 2011 15:49, Dave Martin <dave.mar...@linaro.org> wrote: > > On Fri, Jul 1, 2011 at 6:10 PM, David Gilbert <david.gilb...@linaro.org> > > wrote:
[...] > My patch is having to test an arbitrary address in the commpage in > init code to see if it's new enough to have the new helper that Minor niggle: the address is in no way arbitrary. Although there's no corresponding C symbol, it's a well-known absolute address. > Nicolas just added; Richard's argument is that if it was actually a > VDSO I'd just have linked against a symbol and if the symbol wasn't > there then I would have got a fairly normal linker error - I wouldn't > have needed any special code; and to be honest I think that would also > solve the problem that accessing that wacky address is also a pain for > things like qemu because we're going to have to intercept that read. Note that pre-existing code already calls into the vectors page. Introducing a VDSO interface will not automatically cause all software to stop using the binary interface. How much of a problem that is in practice, I don't know. This doesn't necessarily mean that adding a VDSO interface is bad, but it does mean the existing interface can't easily be changed or removed. Cheers ---Dave _______________________________________________ linaro-dev mailing list linaro-dev@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-dev
