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Suzuki K Poulose
bedf37fc2b
commit80624263faupstream. 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:3c5597e398("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> Cc: stable <stable@vger.kernel.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20201029164559.1268531-2-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.