scsi: qedi: Fix a possible sleep-in-atomic bug in qedi_process_tmf_resp

The driver may sleep under a spinlock.
The function call path is:
qedi_cpu_offline (acquire the spinlock)
  qedi_fp_process_cqes
    qedi_mtask_completion
      qedi_process_tmf_resp
        kzalloc(GFP_KERNEL) --> may sleep

To fix it, GFP_KERNEL is replaced with GFP_ATOMIC.

This bug is found by my static analysis tool(DSAC) and checked by my
code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Acked-by: Manish Rangankar <Manish.Rangankar@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qedi/qedi_fw.c b/drivers/scsi/qedi/qedi_fw.c
index bd302d3..20a9259 100644 (file)
--- a/drivers/scsi/qedi/qedi_fw.c
+++ b/drivers/scsi/qedi/qedi_fw.c
@@ -198,7 +198,7 @@ static void qedi_process_tmf_resp(struct qedi_ctx *qedi,
        cqe_tmp_response = &cqe->cqe_common.iscsi_hdr.tmf_response;
 
        qedi_cmd = task->dd_data;
-       qedi_cmd->tmf_resp_buf = kzalloc(sizeof(*resp_hdr_ptr), GFP_KERNEL);
+       qedi_cmd->tmf_resp_buf = kzalloc(sizeof(*resp_hdr_ptr), GFP_ATOMIC);
        if (!qedi_cmd->tmf_resp_buf) {
                QEDI_ERR(&qedi->dbg_ctx,
                         "Failed to allocate resp buf, cid=0x%x\n",