On 12/03, Linus Torvalds wrote: > > On Tue, Dec 3, 2013 at 12:54 PM, Oleg Nesterov <o...@redhat.com> wrote: > > > > So do you think the patch I sent is wrong? Why? > > I think the TLB shootdown should guarantee that it's ok on other > CPU's, since that's basically what we do on mmap.
OK, thanks. I'll resend this patch. It is still not clear to me if we can simply change a single byte on x86 or not, but at least on powerpc we need to update 4 bytes. Perhaps we can conditionalize these pte games later. > But looking closer at this, I think I see why the old code did what it > did. I think it's breaking shared mmap pages on purpose rather than > dirtying them. Which is probably the right thing to do. Ah, no. uprobes never writes to the shared pages. (hmm, it seems that VM_SHARED check is buggy, but this is offtopic). Otherwise this patch would be very wrong. Oleg. -- 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/
