On Tue, Feb 08, 2005 at 06:10:18PM -0800, Andrew Morton wrote: > We could just remove the printk and stick a comment over it. If the > application later tries to access the not-there pages then it'll just > fault. > > However I worry if there is some way in which we can leave unzeroed memory > accessible to the application, although it's hard to see how that could > happen. > > Daniel, Pavel cruelly chopped you off the Cc when replying. What's your > diagnosis on the below?
It's asking for a lot of unwritable zeroed space. See this: > LOAD 0x000000 0x08048000 0x08048000 0xb7354 0x1b7354 R E 0x1000 > LOAD 0x0b7354 0x08200354 0x08200354 0x1e3e4 0x1f648 RW 0x1000 The 0xb7354 is size to map from the file, the 0x1b7354 is size to map in memory. We're supposed to zero-fill the rest. Now that I think about it I can see why this is a problem - the kernel probably assumes that any segment with MemSiz > FileSiz will be writable. Certainly it's a bit weird for the app to request unwritable zeroed pages. clear_user's probably not the right way to provide the extra zeroing. -- Daniel Jacobowitz CodeSourcery, LLC - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
