s390-tools/s390-tools-sles15sp3-zcryptstats-Fix-handling-of-partial-results-with-man.patch

Subject: [PATCH] [BZ 189239] zcryptstats: Fix handling of partial results with many domains
From: Ingo Franzki <ifranzki@linux.ibm.com>

Description:   zcryptstats: Fix handling of partial results with many domains
Symptom:       Running zcryptstats when many domains are available per cryto
               card does not produce any output, and is hanging in a loop.
Problem:       When many domains per card are available, then the results of 
               the SCDMD CHSC call may not fit into the output area, and a
               partial result is returned. The further results must be 
               retrieved with another CHSC call. Fix the code to pass the 
               correct next-domain to the subsequent CHSC call of a partial
               response. Otherwise the same set of domains 1 to n are retrieved
               again, resulting in an infinite loop, because this will always
               produce a partial result.
Solution:      Fix the code to pass the correct next-domain to the subsequent 
               CHSC call of a partial response.
Reproduction:  Run zcryptstats on a system with many domains per card.
Upstream-ID:   cf2311f1f1de17435b49ba8c8697be91705ba031
Problem-ID:    189239

Upstream-Description:

              zcryptstats: Fix handling of partial results with many domains

              When many domains per card are available, then the results of the SCDMD
              CHSC call may not fit into the output area, and a partial result is
              returned. The further results must be retrieved with another CHSC call.

              Fix the code to pass the correct next-domain to the subsequent CHSC call
              of a partial response. Otherwise the same set of domains 1 to n are
              retrieved again, resulting in an infinite loop, because this will always
              produce a partial result.

              Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
              Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
              Signed-off-by: Jan Hoeppner <hoeppner@linux.ibm.com>


Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
---
 zconf/zcrypt/zcryptstats.c |   14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

--- a/zconf/zcrypt/zcryptstats.c
+++ b/zconf/zcrypt/zcryptstats.c
@@ -1178,8 +1178,14 @@ static int get_apqn_measurement_data(uin
 		scdmd_area.request.header.code = 0x102d;
 		scdmd_area.request.header.length =
 				sizeof(struct chsc_scdmd_request);
-		scdmd_area.request.first_drid.ap_index = card;
-		scdmd_area.request.first_drid.domain_index = g.min_domain;
+		if (scdmd_area.response.p) {
+			scdmd_area.request.first_drid =
+						scdmd_area.response.crid;
+		} else {
+			scdmd_area.request.first_drid.ap_index = card;
+			scdmd_area.request.first_drid.domain_index =
+								g.min_domain;
+		}
 		scdmd_area.request.last_drid.ap_index = card;
 		scdmd_area.request.last_drid.domain_index = g.max_domain;
 		scdmd_area.request.s = 1;
@@ -1217,10 +1223,6 @@ static int get_apqn_measurement_data(uin
 		rc = process_apqn_measurement_data(&scdmd_area);
 		if (rc != 0)
 			break;
-
-		if (scdmd_area.response.p)
-			scdmd_area.request.first_drid =
-					scdmd_area.response.crid;
 	} while (scdmd_area.response.p);
 
 	return rc;