On Mon, Nov 29, 2010 at 01:48:20PM +0800, Jason Wang wrote: > When counting pages we should increase it by 1 instead of VHOST_PAGE_SIZE, > and also make log_write() can correctly process the request across > pages with write_address not start at page boundary. > > Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> Thanks, good catch! But let's to it in small steps: first, a small patch to fix the bug: I think this is equivalent, right? Subject: vhost: correctly set bits of dirty pages When counting pages we should increase address by 1 instead of VHOST_PAGE_SIZE, and also make log_write() can correctly process the request across pages with write_address not starting at page boundary. Reported-by: Jason Wang <jasowang@xxxxxxxxxx> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> --- diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 568eb70..d0a3552 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -887,6 +887,7 @@ static int log_write(void __user *log_base, int r; if (!write_length) return 0; + write_length += write_address % VHOST_PAGE_SIZE; write_address /= VHOST_PAGE_SIZE; for (;;) { u64 base = (u64)(unsigned long)log_base; @@ -900,7 +901,7 @@ static int log_write(void __user *log_base, if (write_length <= VHOST_PAGE_SIZE) break; write_length -= VHOST_PAGE_SIZE; - write_address += VHOST_PAGE_SIZE; + write_address += 1; } return r; } -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html