4.14-stable review patch. If anyone has any objections, please let me know.
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From: Jianchao Wang jianchao.w.wang@oracle.com
[ Upstream commit 89d0c804392bb962553f23dc4c119d11b6bd1675 ]
iscsi tcp will first send out data, then calculate and send data digest. If we don't have BDI_CAP_STABLE_WRITES, the page cache will be written in spite of the on going writeback. Consequently, wrong digest will be got and sent to target.
To fix this, set BDI_CAP_STABLE_WRITES when data digest is enabled in iscsi_tcp .slave_configure callback.
Signed-off-by: Jianchao Wang jianchao.w.wang@oracle.com Acked-by: Chris Leech cleech@redhat.com Acked-by: Lee Duncan lduncan@suse.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/iscsi_tcp.c | 8 ++++++++ 1 file changed, 8 insertions(+)
--- a/drivers/scsi/iscsi_tcp.c +++ b/drivers/scsi/iscsi_tcp.c @@ -37,6 +37,7 @@ #include <linux/kfifo.h> #include <linux/scatterlist.h> #include <linux/module.h> +#include <linux/backing-dev.h> #include <net/tcp.h> #include <scsi/scsi_cmnd.h> #include <scsi/scsi_device.h> @@ -952,6 +953,13 @@ static int iscsi_sw_tcp_slave_alloc(stru
static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev) { + struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(sdev->host); + struct iscsi_session *session = tcp_sw_host->session; + struct iscsi_conn *conn = session->leadconn; + + if (conn->datadgst_en) + sdev->request_queue->backing_dev_info->capabilities + |= BDI_CAP_STABLE_WRITES; blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY); blk_queue_dma_alignment(sdev->request_queue, 0); return 0;