On Tue, Aug 26, 2014 at 06:43:55PM +0300, Kirill A. Shutemov wrote: > On Tue, Aug 26, 2014 at 07:18:13PM +0400, Cyrill Gorcunov wrote: > > > Basically, it's safe if only soft-dirty is allowed to modify vm_flags > > > without down_write(). But why is soft-dirty so special? > > > > because how we use this bit, i mean in normal workload this bit won't > > be used intensively i think so it's not widespread in kernel code > > Weak argument to me. > > What about walk through vmas twice: first with down_write() to modify > vm_flags and vm_page_prot, then downgrade_write() and do > walk_page_range() on every vma?
I still it's undeeded, but for sure using write-lock/downgrade won't hurt, so no argues from my side. -- 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/
