[PATCH v2.2 1/2] check: detect and preserve all coredumps made by a test

["Darrick J. Wong" <djwong@kernel.org>]

From: Darrick J. Wong <djwong@kernel.org>

If someone sets kernel.core_uses_pid (or kernel.core_pattern), any
coredumps generated by fstests might have names that are longer than
just "core".  Since the pid isn't all that useful by itself, let's
record the coredumps by hash when we save them, so that we don't waste
space storing identical crash dumps.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Zorro Lang <zlang@redhat.com>
---
v2.1: use REPORT_DIR per maintainer suggestion
v2.2: use seqres, not REPORT_DIR, since REPORT_DIR doesnt work
---
 check     |   26 ++++++++++++++++++++++----
 common/rc |   22 ++++++++++++++++++++++
 2 files changed, 44 insertions(+), 4 deletions(-)

diff --git a/check b/check
index 3b7bb84ca2..9bebd2a1b9 100755
--- a/check
+++ b/check
@@ -923,11 +923,19 @@ function run_section()
 			sts=$?
 		fi
 
-		if [ -f core ]; then
-			_dump_err_cont "[dumped core]"
-			mv core $RESULT_BASE/$seqnum.core
+		# If someone sets kernel.core_pattern or kernel.core_uses_pid,
+		# coredumps generated by fstests might have a longer name than
+		# just "core".  Use globbing to find the most common patterns,
+		# assuming there are no other coredump capture packages set up.
+		local cores=0
+		for i in core core.*; do
+			test -f "$i" || continue
+			if ((cores++ == 0)); then
+				_dump_err_cont "[dumped core]"
+			fi
+			(_adjust_oom_score 250; _save_coredump "$i")
 			tc_status="fail"
-		fi
+		done
 
 		if [ -f $seqres.notrun ]; then
 			$timestamp && _timestamp
@@ -960,6 +968,16 @@ function run_section()
 			# of the check script itself.
 			(_adjust_oom_score 250; _check_filesystems) || tc_status="fail"
 			_check_dmesg || tc_status="fail"
+
+			# Save any coredumps from the post-test fs checks
+			for i in core core.*; do
+				test -f "$i" || continue
+				if ((cores++ == 0)); then
+					_dump_err_cont "[dumped core]"
+				fi
+				(_adjust_oom_score 250; _save_coredump "$i")
+				tc_status="fail"
+			done
 		fi
 
 		# Reload the module after each test to check for leaks or
diff --git a/common/rc b/common/rc
index d877ac77a0..1a0f167f84 100644
--- a/common/rc
+++ b/common/rc
@@ -4949,6 +4949,28 @@ _create_file_sized()
 	return $ret
 }
 
+# Save an arbitrary coredump to the report directory.
+_save_coredump()
+{
+	local path="$1"
+
+	if [ -z "$seqres" ]; then
+		echo "$path: seqres is not defined; ignoring coredump!"
+		return 1
+	fi
+
+	local core_hash="$(_md5_checksum "$path")"
+	local out_file="${seqres}.core.${core_hash}"
+
+	if [ -s "$out_file" ]; then
+		rm -f "$path"
+		return
+	fi
+	rm -f "$out_file"
+
+	mv "$path" "$out_file"
+}
+
 init_rc
 
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