| Message ID | 20201029164559.1268531-2-mathieu.poirier@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | coresight: Fixes for v5.10-rc2 | expand |
On Thu, Oct 29, 2020 at 10:45:58AM -0600, Mathieu Poirier wrote: > From: Suzuki K Poulose <suzuki.poulose@arm.com> > > With LOCKDEP enabled, CTI driver triggers the following splat due > to uninitialized lock class for dynamically allocated attribute > objects. > > [ 5.372901] coresight etm0: CPU0: ETM v4.0 initialized > [ 5.376694] coresight etm1: CPU1: ETM v4.0 initialized > [ 5.380785] coresight etm2: CPU2: ETM v4.0 initialized > [ 5.385851] coresight etm3: CPU3: ETM v4.0 initialized > [ 5.389808] BUG: key ffff00000564a798 has not been registered! > [ 5.392456] ------------[ cut here ]------------ > [ 5.398195] DEBUG_LOCKS_WARN_ON(1) > [ 5.398233] WARNING: CPU: 1 PID: 32 at kernel/locking/lockdep.c:4623 lockdep_init_map_waits+0x14c/0x260 > [ 5.406149] Modules linked in: > [ 5.415411] CPU: 1 PID: 32 Comm: kworker/1:1 Not tainted 5.9.0-12034-gbbe85027ce80 #51 > [ 5.418553] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) > [ 5.426453] Workqueue: events amba_deferred_retry_func > [ 5.433299] pstate: 40000005 (nZcv daif -PAN -UAO -TCO BTYPE=--) > [ 5.438252] pc : lockdep_init_map_waits+0x14c/0x260 > [ 5.444410] lr : lockdep_init_map_waits+0x14c/0x260 > [ 5.449007] sp : ffff800012bbb720 > ... > > [ 5.531561] Call trace: > [ 5.536847] lockdep_init_map_waits+0x14c/0x260 > [ 5.539027] __kernfs_create_file+0xa8/0x1c8 > [ 5.543539] sysfs_add_file_mode_ns+0xd0/0x208 > [ 5.548054] internal_create_group+0x118/0x3c8 > [ 5.552307] internal_create_groups+0x58/0xb8 > [ 5.556733] sysfs_create_groups+0x2c/0x38 > [ 5.561160] device_add+0x2d8/0x768 > [ 5.565148] device_register+0x28/0x38 > [ 5.568537] coresight_register+0xf8/0x320 > [ 5.572358] cti_probe+0x1b0/0x3f0 > > ... > > Fix this by initializing the attributes when they are allocated. > > Fixes: 3c5597e39812 ("coresight: cti: Add connection information to sysfs") > Reported-by: Leo Yan <leo.yan@linaro.org> > Tested-by: Leo Yan <leo.yan@linaro.org> > Cc: Mike Leach <mike.leach@linaro.org> > Cc: Mathieu Poirier <mathieu.poirier@linaro.org> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> > --- > drivers/hwtracing/coresight/coresight-cti-sysfs.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c > index 392757f3a019..7ff7e7780bbf 100644 > --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c > +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c > @@ -1065,6 +1065,13 @@ static int cti_create_con_sysfs_attr(struct device *dev, > } > eattr->var = con; > con->con_attrs[attr_idx] = &eattr->attr.attr; > + /* > + * Initialize the dynamically allocated attribute > + * to avoid LOCKDEP splat. See include/linux/sysfs.h > + * for more details. > + */ > + sysfs_attr_init(con->con_attrs[attr_idx]); > + > return 0; > } Should go to stable kernels too, as the patch this fixes is in 5.7. I'll add the stable tag here, but feel free to do it yourself next time :) thanks, greg k-h
On Thu, Oct 29, 2020 at 08:10:11PM +0100, Greg KH wrote: > On Thu, Oct 29, 2020 at 10:45:58AM -0600, Mathieu Poirier wrote: > > From: Suzuki K Poulose <suzuki.poulose@arm.com> > > > > With LOCKDEP enabled, CTI driver triggers the following splat due > > to uninitialized lock class for dynamically allocated attribute > > objects. > > > > [ 5.372901] coresight etm0: CPU0: ETM v4.0 initialized > > [ 5.376694] coresight etm1: CPU1: ETM v4.0 initialized > > [ 5.380785] coresight etm2: CPU2: ETM v4.0 initialized > > [ 5.385851] coresight etm3: CPU3: ETM v4.0 initialized > > [ 5.389808] BUG: key ffff00000564a798 has not been registered! > > [ 5.392456] ------------[ cut here ]------------ > > [ 5.398195] DEBUG_LOCKS_WARN_ON(1) > > [ 5.398233] WARNING: CPU: 1 PID: 32 at kernel/locking/lockdep.c:4623 lockdep_init_map_waits+0x14c/0x260 > > [ 5.406149] Modules linked in: > > [ 5.415411] CPU: 1 PID: 32 Comm: kworker/1:1 Not tainted 5.9.0-12034-gbbe85027ce80 #51 > > [ 5.418553] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) > > [ 5.426453] Workqueue: events amba_deferred_retry_func > > [ 5.433299] pstate: 40000005 (nZcv daif -PAN -UAO -TCO BTYPE=--) > > [ 5.438252] pc : lockdep_init_map_waits+0x14c/0x260 > > [ 5.444410] lr : lockdep_init_map_waits+0x14c/0x260 > > [ 5.449007] sp : ffff800012bbb720 > > ... > > > > [ 5.531561] Call trace: > > [ 5.536847] lockdep_init_map_waits+0x14c/0x260 > > [ 5.539027] __kernfs_create_file+0xa8/0x1c8 > > [ 5.543539] sysfs_add_file_mode_ns+0xd0/0x208 > > [ 5.548054] internal_create_group+0x118/0x3c8 > > [ 5.552307] internal_create_groups+0x58/0xb8 > > [ 5.556733] sysfs_create_groups+0x2c/0x38 > > [ 5.561160] device_add+0x2d8/0x768 > > [ 5.565148] device_register+0x28/0x38 > > [ 5.568537] coresight_register+0xf8/0x320 > > [ 5.572358] cti_probe+0x1b0/0x3f0 > > > > ... > > > > Fix this by initializing the attributes when they are allocated. > > > > Fixes: 3c5597e39812 ("coresight: cti: Add connection information to sysfs") > > Reported-by: Leo Yan <leo.yan@linaro.org> > > Tested-by: Leo Yan <leo.yan@linaro.org> > > Cc: Mike Leach <mike.leach@linaro.org> > > Cc: Mathieu Poirier <mathieu.poirier@linaro.org> > > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > > Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> > > --- > > drivers/hwtracing/coresight/coresight-cti-sysfs.c | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c > > index 392757f3a019..7ff7e7780bbf 100644 > > --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c > > +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c > > @@ -1065,6 +1065,13 @@ static int cti_create_con_sysfs_attr(struct device *dev, > > } > > eattr->var = con; > > con->con_attrs[attr_idx] = &eattr->attr.attr; > > + /* > > + * Initialize the dynamically allocated attribute > > + * to avoid LOCKDEP splat. See include/linux/sysfs.h > > + * for more details. > > + */ > > + sysfs_attr_init(con->con_attrs[attr_idx]); > > + > > return 0; > > } > > Should go to stable kernels too, as the patch this fixes is in 5.7. > I'll add the stable tag here, but feel free to do it yourself next time > :) Oh - I (wrongly) assumed all patches with a "Fixes" tag were going to stable. > > thanks, > > greg k-h
diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c index 392757f3a019..7ff7e7780bbf 100644 --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c @@ -1065,6 +1065,13 @@ static int cti_create_con_sysfs_attr(struct device *dev, } eattr->var = con; con->con_attrs[attr_idx] = &eattr->attr.attr; + /* + * Initialize the dynamically allocated attribute + * to avoid LOCKDEP splat. See include/linux/sysfs.h + * for more details. + */ + sysfs_attr_init(con->con_attrs[attr_idx]); + return 0; }