At Fri, 15 May 2009 08:56:00 +0200, Andi Kleen wrote: > Can you describe how it makes it POSIX friendly? > > My understanding was that EFAULT behaviour was undefined in POSIX. > > The obvious hole in the patch is that all these checks are not race > free -- they don't pin pages -- so if there's a parallel unmap even > with your change they can still fail in the middle. ptr = mmap(0, page_size, ....); ... write(fd, ptr + page_size - 256, 512); Write() will fail here, but it can write first 256 bytes. Previously, all 512 bytes were proceeded, but last 256 bytes were zeroed, and sys_write() returned 256. Not very nice too. -- wbr, Vitaly -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
