On 03/16/2012 05:44 PM, Takuya Yoshikawa wrote: > On Fri, 16 Mar 2012 16:28:56 +0800 > Xiao Guangrong <xiaoguangr...@linux.vnet.ibm.com> wrote: > >> Thanks for your explanation, maybe you are right, i do not know migration >> much. >> >> What i worried about is, you have changed the behaviour of GET_DIRTY_LOG, >> in the current one, it can get all the dirty pages when it is called; after >> your change, GET_DIRTY_LOG can get a empty dirty bitmap but dirty page >> exists. > > The current code also see the same situation because nothing prevents the > guest from writing to pages before GET_DIRTY_LOG returns and the userspace > checks the bitmap. Everything is running. >
The current code is under the protection of s-rcu: IIRC, it always holds s-rcu when write guest page and set dirty bit, that mean the dirty page is logged either in the old dirty_bitmap or in the current memslot->dirty_bitmap. Yes? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
