| Message ID | 1509652882-7144-1-git-send-email-thuth@redhat.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | libvirtio: Mark struct virtio_scsi_req_cmd as packed | expand |
On 02.11.2017 21:01, Thomas Huth wrote: > The struct contains an uneven amount of bytes, so we should use > the "packed" attribute to avoid padding problems here. So far the > problems did not show up yet since the struct is filled by Forth > code only and QEMU seems to be quite forgiving about the length of > the descriptor, but anyway, let's better be safe than sorry here. > > Signed-off-by: Thomas Huth <thuth@redhat.com> > --- > lib/libvirtio/virtio-scsi.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/libvirtio/virtio-scsi.h b/lib/libvirtio/virtio-scsi.h > index 451ba4d..d598dea 100644 > --- a/lib/libvirtio/virtio-scsi.h > +++ b/lib/libvirtio/virtio-scsi.h > @@ -47,7 +47,7 @@ struct virtio_scsi_req_cmd { > uint8_t prio; > uint8_t crn; > char cdb[VIRTIO_SCSI_CDB_SIZE]; > -}; > +} __attribute__((packed)); > > /* This is the first element of the "in" scatter-gather list. */ > struct virtio_scsi_resp_cmd { > Ping?
Thomas Huth <thuth@redhat.com> writes: > The struct contains an uneven amount of bytes, so we should use > the "packed" attribute to avoid padding problems here. So far the > problems did not show up yet since the struct is filled by Forth > code only and QEMU seems to be quite forgiving about the length of > the descriptor, but anyway, let's better be safe than sorry here. > > Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> > --- > lib/libvirtio/virtio-scsi.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/libvirtio/virtio-scsi.h b/lib/libvirtio/virtio-scsi.h > index 451ba4d..d598dea 100644 > --- a/lib/libvirtio/virtio-scsi.h > +++ b/lib/libvirtio/virtio-scsi.h > @@ -47,7 +47,7 @@ struct virtio_scsi_req_cmd { > uint8_t prio; > uint8_t crn; > char cdb[VIRTIO_SCSI_CDB_SIZE]; > -}; > +} __attribute__((packed)); > > /* This is the first element of the "in" scatter-gather list. */ > struct virtio_scsi_resp_cmd { > -- > 1.8.3.1 > > _______________________________________________ > SLOF mailing list > SLOF@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/slof
On 06/12/17 19:08, Thomas Huth wrote: > On 02.11.2017 21:01, Thomas Huth wrote: >> The struct contains an uneven amount of bytes, so we should use >> the "packed" attribute to avoid padding problems here. So far the >> problems did not show up yet since the struct is filled by Forth >> code only and QEMU seems to be quite forgiving about the length of >> the descriptor, but anyway, let's better be safe than sorry here. >> >> Signed-off-by: Thomas Huth <thuth@redhat.com> >> --- >> lib/libvirtio/virtio-scsi.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/lib/libvirtio/virtio-scsi.h b/lib/libvirtio/virtio-scsi.h >> index 451ba4d..d598dea 100644 >> --- a/lib/libvirtio/virtio-scsi.h >> +++ b/lib/libvirtio/virtio-scsi.h >> @@ -47,7 +47,7 @@ struct virtio_scsi_req_cmd { >> uint8_t prio; >> uint8_t crn; >> char cdb[VIRTIO_SCSI_CDB_SIZE]; >> -}; >> +} __attribute__((packed)); >> >> /* This is the first element of the "in" scatter-gather list. */ >> struct virtio_scsi_resp_cmd { >> > > Ping? Thanks, applied.
diff --git a/lib/libvirtio/virtio-scsi.h b/lib/libvirtio/virtio-scsi.h index 451ba4d..d598dea 100644 --- a/lib/libvirtio/virtio-scsi.h +++ b/lib/libvirtio/virtio-scsi.h @@ -47,7 +47,7 @@ struct virtio_scsi_req_cmd { uint8_t prio; uint8_t crn; char cdb[VIRTIO_SCSI_CDB_SIZE]; -}; +} __attribute__((packed)); /* This is the first element of the "in" scatter-gather list. */ struct virtio_scsi_resp_cmd {
The struct contains an uneven amount of bytes, so we should use the "packed" attribute to avoid padding problems here. So far the problems did not show up yet since the struct is filled by Forth code only and QEMU seems to be quite forgiving about the length of the descriptor, but anyway, let's better be safe than sorry here. Signed-off-by: Thomas Huth <thuth@redhat.com> --- lib/libvirtio/virtio-scsi.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)