[PATCH] ppc64: still allow to move on if the emergency stacks info fails to initialize

[Lianbo Jiang <lijiang@xxxxxxxxxx>]

Currently crash will fail and then exit, if the initialization of
the emergency stacks information fails. In real customer environments,
sometimes, a vmcore may be partially damaged, although such vmcores
are rare. For example:

  # ./crash ../3.10.0-1127.18.2.el7.ppc64le/vmcore ../3.10.0-1127.18.2.el7.ppc64le/vmlinux  -s
  crash: invalid kernel virtual address: 38  type: "paca->emergency_sp"
  #

Lets try to keep loading vmcore if such issues happen, so call
the readmem() with the RETURN_ON_ERROR instead of FAULT_ON_ERROR,
which allows the crash move on.

Reported-by: Dave Wysochanski <dwysocha@xxxxxxxxxx>
Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
---
 ppc64.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/ppc64.c b/ppc64.c
index 4ea1f7c0c6f8..f94b402ec64d 100644
--- a/ppc64.c
+++ b/ppc64.c
@@ -1224,13 +1224,13 @@ ppc64_init_paca_info(void)
 		ulong paca_loc;
 
 		readmem(symbol_value("paca_ptrs"), KVADDR, &paca_loc, sizeof(void *),
-			"paca double pointer", FAULT_ON_ERROR);
+			"paca double pointer", RETURN_ON_ERROR);
 		readmem(paca_loc, KVADDR, paca_ptr, sizeof(void *) * kt->cpus,
-			"paca pointers", FAULT_ON_ERROR);
+			"paca pointers", RETURN_ON_ERROR);
 	} else if (symbol_exists("paca") &&
 		   (get_symbol_type("paca", NULL, NULL) == TYPE_CODE_PTR)) {
 		readmem(symbol_value("paca"), KVADDR, paca_ptr, sizeof(void *) * kt->cpus,
-			"paca pointers", FAULT_ON_ERROR);
+			"paca pointers", RETURN_ON_ERROR);
 	} else {
 		free(paca_ptr);
 		return;
@@ -1245,7 +1245,7 @@ ppc64_init_paca_info(void)
 		for (i = 0; i < kt->cpus; i++)
 			readmem(paca_ptr[i] + offset, KVADDR, &ms->emergency_sp[i],
 				sizeof(void *), "paca->emergency_sp",
-				FAULT_ON_ERROR);
+				RETURN_ON_ERROR);
 	}
 
 	if (MEMBER_EXISTS("paca_struct", "nmi_emergency_sp")) {
@@ -1256,7 +1256,7 @@ ppc64_init_paca_info(void)
 		for (i = 0; i < kt->cpus; i++)
 			readmem(paca_ptr[i] + offset, KVADDR, &ms->nmi_emergency_sp[i],
 				sizeof(void *), "paca->nmi_emergency_sp",
-				FAULT_ON_ERROR);
+				RETURN_ON_ERROR);
 	}
 
 	if (MEMBER_EXISTS("paca_struct", "mc_emergency_sp")) {
@@ -1267,7 +1267,7 @@ ppc64_init_paca_info(void)
 		for (i = 0; i < kt->cpus; i++)
 			readmem(paca_ptr[i] + offset, KVADDR, &ms->mc_emergency_sp[i],
 				sizeof(void *), "paca->mc_emergency_sp",
-				FAULT_ON_ERROR);
+				RETURN_ON_ERROR);
 	}
 
 	free(paca_ptr);
-- 
2.37.1

--
Crash-utility mailing list
Crash-utility@xxxxxxxxxx
https://listman.redhat.com/mailman/listinfo/crash-utility
Contribution Guidelines: https://github.com/crash-utility/crash/wiki