commit eed968607d656a218712df47a5e0432c21fd6994 Author: Daniel P. Berrange Date: Mon Jan 16 18:11:40 2012 +0000 hw/9pfs: Remove O_NOATIME flag from 9pfs open() calls in readonly mode When 2c74c2cb4bedddbfa67628fbd5f9273b4e0e9903 added support for the 'readonly' flag against 9p filesystems, it also made QEMU add the O_NOATIME flag as a side-effect. The O_NOATIME flag, however, may only be set by the file owner, or a user with CAP_FOWNER capability. QEMU cannot assume that this is the case for filesytems exported to QEMU. eg, run QEMU as non-root, and attempt to pass the host OS filesystem through to the guest OS with readonly enable. The result is that the guest OS cannot open any files at all. If O_NOATIME is really required, it should be optionally enabled via a separate QEMU command line flag. * hw/9pfs/virtio-9p.c: Remove O_NOATIME Acked-by: M. Mohan Kumar Signed-off-by: Daniel P. Berrange Signed-off-by: Aneesh Kumar K.V diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c index dfe2025..a72ffc3 100644 --- a/hw/9pfs/virtio-9p.c +++ b/hw/9pfs/virtio-9p.c @@ -1391,7 +1391,6 @@ static void v9fs_open(void *opaque) err = -EROFS; goto out; } - flags |= O_NOATIME; } err = v9fs_co_open(pdu, fidp, flags); if (err < 0) {