Currently we call virSetDeviceUnprivSGIO with val == 0 if a block device has an sgio attribute. But for sgio='filtered', we know that a kernel with no unpriv_sgio support will always behave as the user wanted. In this case, there is no need to call the function and report a (bogus) error. Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com&gt; --- src/qemu/qemu_process.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index b560d2e..4c152b2 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -3455,36 +3455,35 @@ qemuProcessReconnectAll(virConnectPtr conn, virQEMUDriverPtr driver) int qemuSetUnprivSGIO(virDomainDiskDefPtr disk) { + char *sysfs_path = NULL; int val = -1; + int ret = 0; /* "sgio" is only valid for block disk; cdrom * and floopy disk can have empty source. */ if (disk->type != VIR_DOMAIN_DISK_TYPE_BLOCK || + disk->device != VIR_DOMAIN_DISK_DEVICE_LUN || !disk->src) return 0; - if (disk->sgio) - val = (disk->sgio == VIR_DOMAIN_DISK_SGIO_UNFILTERED); - - /* Ignore the setting if unpriv_sgio is not supported by the - * kernel, otherwise defaults to filter the SG_IO commands, - * I.E. Set unpriv_sgio to 0. - */ - if (disk->sgio == VIR_DOMAIN_DISK_SGIO_DEFAULT && - disk->device == VIR_DOMAIN_DISK_DEVICE_LUN) { - char *sysfs_path = NULL; + sysfs_path = virGetUnprivSGIOSysfsPath(disk->src, NULL); + if (sysfs_path == NULL) + return -1; - if ((sysfs_path = virGetUnprivSGIOSysfsPath(disk->src, NULL)) && - virFileExists(sysfs_path)) - val = 0; - VIR_FREE(sysfs_path); - } + /* By default, filter the SG_IO commands, i.e. set unpriv_sgio to 0. */ + val = (disk->sgio == VIR_DOMAIN_DISK_SGIO_UNFILTERED); - if (val >= 0 && virSetDeviceUnprivSGIO(disk->src, NULL, val) < 0) - return -1; + /* Do not do anything if unpriv_sgio is not supported by the kernel and the + * whitelist is enabled. But if requesting unfiltered access, always call + * virSetDeviceUnprivSGIO, to report an error for unsupported unpriv_sgio. + */ + if ((virFileExists(sysfs_path) || val == 1) && + virSetDeviceUnprivSGIO(disk->src, NULL, val) < 0) + ret = -1; - return 0; + VIR_FREE(sysfs_path); + return ret; } int qemuProcessStart(virConnectPtr conn, -- 1.8.1.2