From: Hiroya Nozaki <nozaki.hir...@jp.fujitsu.com> Running multiple mounts at the same time results in lustre_profile_list corruption when adding a new profile.
This patch adds a new spin_lock to protect the list and avoid the bug Signed-off-by: Hiroya Nozaki <nozaki.hir...@jp.fujitsu.com> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6600 Reviewed-on: http://review.whamcloud.com/14896 Reviewed-by: Andreas Dilger <andreas.dil...@intel.com> Reviewed-by: Jian Yu <jian...@intel.com> Reviewed-by: Oleg Drokin <oleg.dro...@intel.com> Signed-off-by: James Simmons <jsimm...@infradead.org> --- drivers/staging/lustre/lustre/include/obd_class.h | 3 + drivers/staging/lustre/lustre/llite/llite_lib.c | 2 + .../staging/lustre/lustre/obdclass/obd_config.c | 57 +++++++++++++++++--- 3 files changed, 54 insertions(+), 8 deletions(-) diff --git a/drivers/staging/lustre/lustre/include/obd_class.h b/drivers/staging/lustre/lustre/include/obd_class.h index 476b1e4..f79133c 100644 --- a/drivers/staging/lustre/lustre/include/obd_class.h +++ b/drivers/staging/lustre/lustre/include/obd_class.h @@ -182,10 +182,13 @@ struct lustre_profile { char *lp_profile; char *lp_dt; char *lp_md; + int lp_refs; + bool lp_list_deleted; }; struct lustre_profile *class_get_profile(const char *prof); void class_del_profile(const char *prof); +void class_put_profile(struct lustre_profile *lprof); void class_del_profiles(void); #if LUSTRE_TRACKS_LOCK_EXP_REFS diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c index b896ac1..308da06 100644 --- a/drivers/staging/lustre/lustre/llite/llite_lib.c +++ b/drivers/staging/lustre/lustre/llite/llite_lib.c @@ -929,6 +929,8 @@ int ll_fill_super(struct super_block *sb, struct vfsmount *mnt) out_free: kfree(md); kfree(dt); + if (lprof) + class_put_profile(lprof); if (err) ll_put_super(sb); else if (sbi->ll_flags & LL_SBI_VERBOSE) diff --git a/drivers/staging/lustre/lustre/obdclass/obd_config.c b/drivers/staging/lustre/lustre/obdclass/obd_config.c index bbed1b7..017bdac 100644 --- a/drivers/staging/lustre/lustre/obdclass/obd_config.c +++ b/drivers/staging/lustre/lustre/obdclass/obd_config.c @@ -585,16 +585,21 @@ static int class_del_conn(struct obd_device *obd, struct lustre_cfg *lcfg) } static LIST_HEAD(lustre_profile_list); +static DEFINE_SPINLOCK(lustre_profile_list_lock); struct lustre_profile *class_get_profile(const char *prof) { struct lustre_profile *lprof; + spin_lock(&lustre_profile_list_lock); list_for_each_entry(lprof, &lustre_profile_list, lp_list) { if (!strcmp(lprof->lp_profile, prof)) { + lprof->lp_refs++; + spin_unlock(&lustre_profile_list_lock); return lprof; } } + spin_unlock(&lustre_profile_list_lock); return NULL; } EXPORT_SYMBOL(class_get_profile); @@ -639,7 +644,11 @@ static int class_add_profile(int proflen, char *prof, int osclen, char *osc, } } + spin_lock(&lustre_profile_list_lock); + lprof->lp_refs = 1; + lprof->lp_list_deleted = false; list_add(&lprof->lp_list, &lustre_profile_list); + spin_unlock(&lustre_profile_list_lock); return err; free_lp_dt: @@ -659,27 +668,59 @@ void class_del_profile(const char *prof) lprof = class_get_profile(prof); if (lprof) { + spin_lock(&lustre_profile_list_lock); + /* because get profile increments the ref counter */ + lprof->lp_refs--; list_del(&lprof->lp_list); - kfree(lprof->lp_profile); - kfree(lprof->lp_dt); - kfree(lprof->lp_md); - kfree(lprof); + lprof->lp_list_deleted = true; + spin_unlock(&lustre_profile_list_lock); + + class_put_profile(lprof); } } EXPORT_SYMBOL(class_del_profile); +void class_put_profile(struct lustre_profile *lprof) +{ + spin_lock(&lustre_profile_list_lock); + if (--lprof->lp_refs > 0) { + LASSERT(lprof->lp_refs > 0); + spin_unlock(&lustre_profile_list_lock); + return; + } + spin_unlock(&lustre_profile_list_lock); + + /* confirm not a negative number */ + LASSERT(!lprof->lp_refs); + + /* + * At least one class_del_profile/profiles must be called + * on the target profile or lustre_profile_list will corrupt + */ + LASSERT(lprof->lp_list_deleted); + kfree(lprof->lp_profile); + kfree(lprof->lp_dt); + kfree(lprof->lp_md); + kfree(lprof); +} +EXPORT_SYMBOL(class_put_profile); + /* COMPAT_146 */ void class_del_profiles(void) { struct lustre_profile *lprof, *n; + spin_lock(&lustre_profile_list_lock); list_for_each_entry_safe(lprof, n, &lustre_profile_list, lp_list) { list_del(&lprof->lp_list); - kfree(lprof->lp_profile); - kfree(lprof->lp_dt); - kfree(lprof->lp_md); - kfree(lprof); + lprof->lp_list_deleted = true; + spin_unlock(&lustre_profile_list_lock); + + class_put_profile(lprof); + + spin_lock(&lustre_profile_list_lock); } + spin_unlock(&lustre_profile_list_lock); } EXPORT_SYMBOL(class_del_profiles); -- 1.7.1
