From ccdab3d6e881649f05110d9098fd248d2753aaf3 Mon Sep 17 00:00:00 2001 From: Brian Foster Date: Wed, 14 Jun 2017 21:29:12 -0700 Subject: xfs: define bug_on_assert debug mode sysfs tunable In DEBUG mode, assert failures unconditionally trigger a kernel BUG. This is useful in diagnostic situations to panic a system and collect detailed state information at the time of a failure. This can also cause problems in cases where DEBUG mode code is desired but it is preferable not trigger kernel BUGs on assert failure. For example, during development of new code or during certain xfstests tests that intentionally cause corruption and test the kernel for survival (but otherwise may expect to trigger assert failures). To provide additional flexibility, create the /fs/xfs/debug/bug_on_assert tunable to configure assert failure behavior at runtime. This tunable is only available in DEBUG mode and is enabled by default to preserve existing default behavior. When disabled, assert failures in DEBUG mode result in kernel warnings. Signed-off-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_sysfs.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'fs/xfs/xfs_sysfs.c') diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c index 80ac15fb9638..ec6e0e2f95d6 100644 --- a/fs/xfs/xfs_sysfs.c +++ b/fs/xfs/xfs_sysfs.c @@ -145,6 +145,38 @@ struct kobj_type xfs_mp_ktype = { #ifdef DEBUG /* debug */ +STATIC ssize_t +bug_on_assert_store( + struct kobject *kobject, + const char *buf, + size_t count) +{ + int ret; + int val; + + ret = kstrtoint(buf, 0, &val); + if (ret) + return ret; + + if (val == 1) + xfs_globals.bug_on_assert = true; + else if (val == 0) + xfs_globals.bug_on_assert = false; + else + return -EINVAL; + + return count; +} + +STATIC ssize_t +bug_on_assert_show( + struct kobject *kobject, + char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.bug_on_assert ? 1 : 0); +} +XFS_SYSFS_ATTR_RW(bug_on_assert); + STATIC ssize_t log_recovery_delay_store( struct kobject *kobject, @@ -176,6 +208,7 @@ log_recovery_delay_show( XFS_SYSFS_ATTR_RW(log_recovery_delay); static struct attribute *xfs_dbg_attrs[] = { + ATTR_LIST(bug_on_assert), ATTR_LIST(log_recovery_delay), NULL, }; -- cgit v1.2.1