Commit Graph

26 Commits

Author SHA1 Message Date
Alexander Shishkin
d44e8dd999 intel_th: Fix user-visible error codes
commit ce666be89a8a09c5924ff08fc32e119f974bdab6 upstream.

There are a few places in the driver that end up returning ENOTSUPP to
the user, replace those with EINVAL.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Fixes: ba82664c134ef ("intel_th: Add Memory Storage Unit driver")
Cc: stable@vger.kernel.org # v4.4+
Link: https://lore.kernel.org/r/20200317062215.15598-6-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-07 14:14:24 +02:00
Ding Xiang
4b07cd023f stm class: Fix a double free of stm_source_device
commit 961b6ffe0e2c403b09a8efe4a2e986b3c415391a upstream.

In the error path of stm_source_register_device(), the kfree is
unnecessary, as the put_device() before it ends up calling
stm_source_device_release() to free stm_source_device, leading to
a double free at the outer kfree() call. Remove it.

Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 7bd1d4093c2fa ("stm class: Introduce an abstraction for System Trace Module devices")
Link: https://lore.kernel.org/linux-arm-kernel/1563354988-23826-1-git-send-email-dingxiang@cmss.chinamobile.com/
Cc: stable@vger.kernel.org # v4.4+
Link: https://lore.kernel.org/r/20190821074955.3925-2-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-06 21:33:50 +02:00
Alexander Shishkin
6b0b8836fd intel_th: msu: Fix single mode with disabled IOMMU
commit 918b8646497b5dba6ae82d4a7325f01b258972b9 upstream.

Commit 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU") switched
the single mode code to use dma mapping pages obtained from the page
allocator, but with IOMMU disabled, that may lead to using SWIOTLB bounce
buffers and without additional sync'ing, produces empty trace buffers.

Fix this by using a DMA32 GFP flag to the page allocation in single mode,
as the device supports full 32-bit DMA addressing.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Ammy Yi <ammy.yi@intel.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20190621161930.60785-4-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-06 20:04:57 +02:00
Alexander Shishkin
265445fbe7 intel_th: msu: Fix single mode with IOMMU
commit 4e0eaf239fb33ebc671303e2b736fa043462e2f4 upstream.

Currently, the pages that are allocated for the single mode of MSC are not
mapped into the device's dma space and the code is incorrectly using
*_to_phys() in place of a dma address. This fails with IOMMU enabled and
is otherwise bad practice.

Fix the single mode buffer allocation to map the pages into the device's
DMA space.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: ba82664c134e ("intel_th: Add Memory Storage Unit driver")
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-06 18:13:40 +02:00
Tingwei Zhang
b71271bef6 stm class: Fix channel free in stm output free path
commit ee496da4c3915de3232b5f5cd20e21ae3e46fe8d upstream.

Number of free masters is not set correctly in stm
free path. Fix this by properly adding the number
of output channels before setting them to 0 in
stm_output_disclaim().

Currently it is equivalent to doing nothing since
master->nr_free is incremented by 0.

Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices")
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Cc: stable@vger.kernel.org # v4.4
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-06 18:13:36 +02:00
Alexander Shishkin
ce1308637b intel_th: gth: Fix an off-by-one in output unassigning
commit 91d3f8a629849968dc91d6ce54f2d46abf4feb7f upstream.

Commit 9ed3f22223c3 ("intel_th: Don't reference unassigned outputs")
fixes a NULL dereference for all masters except the last one ("256+"),
which keeps the stale pointer after the output driver had been unassigned.

Fix the off-by-one.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 9ed3f22223c3 ("intel_th: Don't reference unassigned outputs")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-06 16:40:30 +02:00
Sai Prakash Ranjan
4bb301ddf9 coresight: etm4x: Add support to enable ETMv4.2
[ Upstream commit 5666dfd1d8a45a167f0d8b4ef47ea7f780b1f24a ]

SDM845 has ETMv4.2 and can use the existing etm4x driver.
But the current etm driver checks only for ETMv4.0 and
errors out for other etm4x versions. This patch adds this
missing support to enable SoC's with ETMv4x to use same
driver by checking only the ETM architecture major version
number.

Without this change, we get below error during etm probe:

/ # dmesg | grep etm
[    6.660093] coresight-etm4x: probe of 7040000.etm failed with error -22
[    6.666902] coresight-etm4x: probe of 7140000.etm failed with error -22
[    6.673708] coresight-etm4x: probe of 7240000.etm failed with error -22
[    6.680511] coresight-etm4x: probe of 7340000.etm failed with error -22
[    6.687313] coresight-etm4x: probe of 7440000.etm failed with error -22
[    6.694113] coresight-etm4x: probe of 7540000.etm failed with error -22
[    6.700914] coresight-etm4x: probe of 7640000.etm failed with error -22
[    6.707717] coresight-etm4x: probe of 7740000.etm failed with error -22

With this change, etm probe is successful:

/ # dmesg | grep etm
[    6.659198] coresight-etm4x 7040000.etm: CPU0: ETM v4.2 initialized
[    6.665848] coresight-etm4x 7140000.etm: CPU1: ETM v4.2 initialized
[    6.672493] coresight-etm4x 7240000.etm: CPU2: ETM v4.2 initialized
[    6.679129] coresight-etm4x 7340000.etm: CPU3: ETM v4.2 initialized
[    6.685770] coresight-etm4x 7440000.etm: CPU4: ETM v4.2 initialized
[    6.692403] coresight-etm4x 7540000.etm: CPU5: ETM v4.2 initialized
[    6.699024] coresight-etm4x 7640000.etm: CPU6: ETM v4.2 initialized
[    6.705646] coresight-etm4x 7740000.etm: CPU7: ETM v4.2 initialized

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 14:50:34 +02:00
Geert Uytterhoeven
c43af3d243 stm class: Hide STM-specific options if STM is disabled
[ Upstream commit 4a2e2b19f96acfc037a9773c7729d133ce1e7e3b ]

If STM=n, it doesn't make sense to ask about STM_DUMMY and
STM_SOURCE_CONSOLE support, which are not even built when enabled
anyway. Hence hide these options if STM=n.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 13:03:45 +02:00
Mathieu Poirier
ec73ccd8f6 coresight: removing bind/unbind options from sysfs
[ Upstream commit b15f0fb657e040401d875d11ae13b269af8a16e0 ]

The coresight drivers have absolutely no control over bind and unbind
operations triggered from sysfs. The operations simply can't be
cancelled or denied event when one or several tracing sessions are
under way.  Since the memory associated to individual device is
invariably freed, the end result is a kernel crash when the path from
source to sink is travelled again as demonstrated here[1].

One solution could be to keep track of all the path (i.e tracing
session) that get created and iterate through the elements of those path
looking for the coresight device that is being removed.  This proposition
doesn't scale well since there is no upper bound on the amount of
concurrent trace session that can be created.

With the above in mind, this patch prevent devices from being unbounded
from their driver by using the driver->suppress_bind_attr option.  That way
trace sessions can be managed without fearing to loose devices.

Since device can't be removed anymore the xyz_remove() functions found in
each driver is also removed.

[1]. http://www.spinics.net/lists/arm-kernel/msg474952.html

Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 13:03:43 +02:00
Alexander Shishkin
c024cce43f stm class: Fix stm device initialization order
[ Upstream commit 389b6699a2aa0b457aa69986e9ddf39f3b4030fd ]

Currently, stm_register_device() makes the device visible and then
proceeds to initializing spinlocks and other properties, which leaves
a window when the device can already be opened but is not yet fully
operational.

Fix this by reversing the initialization order.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:52:24 +02:00
Alexander Shishkin
ae21109473 stm class: Do not leak the chrdev in error path
[ Upstream commit cbe4a61d1ddc4790d950ca8c33ef79ee68ef5e2b ]

Currently, the error path of stm_register_device() forgets to unregister
the chrdev. Fix this.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:52:22 +02:00
Eric Long
30030bc938 coresight: etm4x: Check every parameter used by dma_xx_coherent.
[ Upstream commit 61390593f72377c3a8f41ef998462e2d3985adac ]

The dma_alloc_coherent return an "void *" not an "void __iomen *".
It uses the wrong parameters when calls dma_free_coherent function.

The sparse tool output logs as the following:
coresight-tmc.c:199:23:    expected void *<noident>
coresight-tmc.c:199:23:    got void [noderef] <asn:2>*vaddr
coresight-tmc.c:336:30: warning: incorrect type in assignment
(different address spaces)
coresight-tmc.c:336:30:    expected char *buf
coresight-tmc.c:336:30:    got void [noderef] <asn:2>*
coresight-tmc.c:769:50: warning: incorrect type in argument 4
(different base types)
coresight-tmc.c:769:50:    expected unsigned long long
[unsigned] [usertype] dma_handle
coresight-tmc.c:769:50:    got restricted gfp_t

Signed-off-by: Eric Long <eric.long@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:51:02 +02:00
Eric Long
d70fd061cb coresight: "DEVICE_ATTR_RO" should defined as static.
[ Upstream commit bf16e5b8cdeabc1fe6565af0be475bb2084dc388 ]

"DEVICE_ATTR_RO(name)" should be defined as static. And
there is an unnecessary space at the front of the code.

The sparse tool output logs as the following:
coresight-etm4x.c:2224:1: warning: symbol 'dev_attr_trcoslsr' was
not declared. Should it be static?
coresight-etm4x.c:2225:1: warning: symbol 'dev_attr_trcpdcr' was
not declared. Should it be static?
coresight-etm4x.c:2226:1: warning: symbol 'dev_attr_trcpdsr' was
not declared. Should it be static?
And the smatch tool output logs as the following:
of_coresight.c:89 of_coresight_alloc_memory() warn:
inconsistent indenting

Signed-off-by: Eric Long <eric.long@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:51:00 +02:00
Alexander Shishkin
b8a55aab00 stm class: Fix a race in unlinking
[ Upstream commit b4ca34aaf78ed0cdfc15956d377064104257a437 ]

There is a window in stm_source_link_drop(), during which the source's
link may change before locks are acquired. When this happens, it throws
a warning, since this is not an expected scenario.

This patch handles the race in such a way that if the link appears to
have changed by the time we took the locks, it will release them and
repeat the whole unlinking procedure from the beginning, unless the
other contender beat us to it.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:58 +02:00
Alexander Shishkin
ec215f3c92 stm class: Fix unbalanced module/device refcounting
[ Upstream commit f7c81c7176c72c7899390754b4b038a64b296e4d ]

STM code takes references to the stm device and its module for the
duration of the character device's existence or the stm_source link.
Dropping these references is not well balanced everywhere, which may
lead to leaks.

This patch balances the acquisition and releasing of these two
references and annotates each site so that it's easier to verify
correctness by reading the code.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:56 +02:00
Alexander Shishkin
33ecbd2717 stm class: Guard output assignment against concurrency
[ Upstream commit cde4ad8368840e414ecf67db258fe1dabaa5fd2e ]

It is possible to concurrently assign the same output (a character
device writer or an stm_source device) to different stm devices,
which sets off a strategically placed warning in stm_output_assign().

To avoid this, use a spinlock to serialize (un)assignments between
outputs and stm devices.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:54 +02:00
Alexander Shishkin
d037f358f1 stm class: Fix unlocking braino in the error path
[ Upstream commit 1810f2c44817c74ca3d05d1e3981e3a2e2ceb6f5 ]

If an illegal attempt is made to unlink stm source device from an
stm device, the stm device's link spinlock mistakenly remains locked.
While this really shouldn't happen (there's a warning in place), the
locking should remain in order so that we can still recover from this
situation if it indeed does happen.

This patch unifies the unlocking in the exit path of
__stm_source_link_drop() to fix this.

Reported-by: Laurent Fert <laurent.fert@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:52 +02:00
Alexander Shishkin
a18cf3fe25 stm class: Support devices with multiple instances
[ Upstream commit 59be422e4ce10e3d49d4c9407a80fab8a9b7bc84 ]

By convention, the name of the stm policy directory in configfs consists of
the device name to which it applies and the actual policy name, separated
by a dot. Now, some devices already have dots in their names that separate
name of the actual device from its instance identifier. Such devices will
result in two (or more, who can tell) dots in the policy directory name.

Existing policy code, however, will treat the first dot as the one that
separates device name from policy name, therefore failing the above case.

This patch makes the last dot in the directory name be the separator, thus
prohibiting dots from being used in policy names.

Suggested-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:50 +02:00
Alexander Shishkin
35f8e74b46 stm class: Prevent user-controllable allocations
[ Upstream commit f08b18266c7116e2ec6885dd53a928f580060a71 ]

Currently, the character device write method allocates a temporary buffer
for user's data, but the user's data size is not sanitized and can cause
arbitrarily large allocations via kzalloc() or an integer overflow that
will then result in overwriting kernel memory.

This patch trims the input buffer size to avoid these issues.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:48 +02:00
Alexander Shishkin
9ed5b13a98 stm class: Fix link list locking
[ Upstream commit c74f7e8281add80bdfa0ad2998b8df287b13df73 ]

Currently, the list of stm_sources linked to an stm device is protected by
a spinlock, which also means that sources' .unlink() method is called under
this spinlock. However, this method may (and does) sleep, which means
trouble.

This patch slightly reworks locking around stm::link_list so that bits that
might_sleep() are called with a mutex held instead. Modification of this
list requires both mutex and spinlock to be held, while looking at the list
can be done under either mutex or spinlock.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:47 +02:00
Alexander Shishkin
d15b3d403b stm class: Fix locking in unbinding policy path
[ Upstream commit 4c127fd16e6b33ecb7badc091480c84ea9aebeb6 ]

Right now, if stm device removal has to unbind from a policy (that is,
an stm device that has STP policy, gets removed), it will trigger a
nested lock on the stm device's policy mutex.

This patch fixes the problem by moving the locking from the policy
unbinding to policy removal (configfs path), where it's actually needed;
the other caller of the policy unbinding function already takes the
mutex around the call.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:45 +02:00
Mathieu Poirier
5b6dd51167 coresight: remove csdev's link from topology
[ Upstream commit ad725aee070caf8fa93d84d6fb78321f9642db18 ]

In function 'coresight_unregister()', all references to the csdev that
is being taken away need to be removed from the topology.  Otherwise
building the next coresight path from source to sink may use memory
that has been released.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:43 +02:00
Mathieu Poirier
6a22afad61 coresight: release reference taken by 'bus_find_device()'
[ Upstream commit f2dfab3568fc32afeac8b698481e80e7ab2dc658 ]

The reference count taken by function bus_find_device() needs
to be released if a child device is found, something this patch
is adding.

Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:41 +02:00
Mathieu Poirier
dad04e5e33 coresight: coresight_unregister() function cleanup
[ Upstream commit fae54158792aec705620bdc3938d342879204f0c ]

In its current form the code never frees csdev->refcnt allocated
in coresight_register().  There is also a problem with csdev->conns
that is freed before device_unregister() rather than in the device
release function.

This patch addresses both issues by moving kfree(csdev->conns) to
coresight_device_release() and freeing csdev->refcnt, also in
the same function.

Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:39 +02:00
Mathieu Poirier
86ffcb99d9 coresight: fixing lockdep error
[ Upstream commit a9ddc71f5840c2711e530f2e055b278f79948b29 ]

On some platform the following lockdep error occurs when doing simple
manipulations:

    [   23.197021]
    [   23.198608] ======================================================
    [   23.205078] [ INFO: possible circular locking dependency detected ]
    [   23.211639] 4.4.0-rc8-00025-gbbf360b #172 Not tainted
    [   23.216918] -------------------------------------------------------
    [   23.223480] sh/858 is trying to acquire lock:
    [   23.228057]  (coresight_mutex){+.+.+.}, at: [<c0415d40>] coresight_enable+0x1c/0x1b4
    [   23.236206]
    [   23.236206] but task is already holding lock:
    [   23.242309]  (s_active#52){++++.+}, at: [<c01d4b40>] kernfs_fop_write+0x5c/0x1c0
    [   23.250122]
    [   23.250122] which lock already depends on the new lock.
    [   23.250122]
    [   23.258697]
    [   23.258697] the existing dependency chain (in reverse order) is:
    [   23.266510]
    -> #1 (s_active#52){++++.+}:
    [   23.270843]        [<c01d30ec>] __kernfs_remove+0x294/0x35c
    [   23.276672]        [<c01d3e44>] kernfs_remove_by_name_ns+0x44/0x8c
    [   23.283172]        [<c01d6318>] remove_files+0x3c/0x84
    [   23.288543]        [<c01d66b4>] sysfs_remove_group+0x48/0x9c
    [   23.294494]        [<c01d6734>] sysfs_remove_groups+0x2c/0x3c
    [   23.300506]        [<c030b658>] device_remove_attrs+0x5c/0x74
    [   23.306549]        [<c030c290>] device_del+0x110/0x218
    [   23.311950]        [<c030c3c4>] device_unregister+0x2c/0x6c
    [   23.317779]        [<c04156d8>] coresight_unregister+0x30/0x40
    [   23.323883]        [<c041a290>] etm_probe+0x228/0x2e8
    [   23.329193]        [<c02bc760>] amba_probe+0xe4/0x160
    [   23.334503]        [<c0310540>] driver_probe_device+0x23c/0x480
    [   23.340728]        [<c0310820>] __driver_attach+0x9c/0xa0
    [   23.346374]        [<c030e400>] bus_for_each_dev+0x70/0xa4
    [   23.352142]        [<c030fcf4>] driver_attach+0x24/0x28
    [   23.357604]        [<c030f86c>] bus_add_driver+0x1e0/0x278
    [   23.363372]        [<c0310d48>] driver_register+0x80/0x100
    [   23.369110]        [<c02bc508>] amba_driver_register+0x58/0x5c
    [   23.375244]        [<c0749514>] etm_driver_init+0x18/0x1c
    [   23.380889]        [<c0009918>] do_one_initcall+0xc4/0x20c
    [   23.386657]        [<c0715e7c>] kernel_init_freeable+0x160/0x208
    [   23.392974]        [<c052d7fc>] kernel_init+0x18/0xf0
    [   23.398254]        [<c0010850>] ret_from_fork+0x14/0x24
    [   23.403747]
    -> #0 (coresight_mutex){+.+.+.}:
    [   23.408447]        [<c008ed60>] lock_acquire+0xe4/0x210
    [   23.413909]        [<c0530a30>] mutex_lock_nested+0x74/0x450
    [   23.419860]        [<c0415d40>] coresight_enable+0x1c/0x1b4
    [   23.425689]        [<c0416030>] enable_source_store+0x58/0x68
    [   23.431732]        [<c030b358>] dev_attr_store+0x20/0x2c
    [   23.437286]        [<c01d55e8>] sysfs_kf_write+0x50/0x54
    [   23.442871]        [<c01d4ba8>] kernfs_fop_write+0xc4/0x1c0
    [   23.448699]        [<c015b60c>] __vfs_write+0x34/0xe4
    [   23.454040]        [<c015bf38>] vfs_write+0x98/0x174
    [   23.459228]        [<c015c7a8>] SyS_write+0x4c/0xa8
    [   23.464355]        [<c00107c0>] ret_fast_syscall+0x0/0x1c
    [   23.470031]
    [   23.470031] other info that might help us debug this:
    [   23.470031]
    [   23.478393]  Possible unsafe locking scenario:
    [   23.478393]
    [   23.484619]        CPU0                    CPU1
    [   23.489349]        ----                    ----
    [   23.494079]   lock(s_active#52);
    [   23.497497]                                lock(coresight_mutex);
    [   23.503906]                                lock(s_active#52);
    [   23.509918]   lock(coresight_mutex);
    [   23.513702]
    [   23.513702]  *** DEADLOCK ***
    [   23.513702]
    [   23.519897] 3 locks held by sh/858:
    [   23.523529]  #0:  (sb_writers#7){.+.+.+}, at: [<c015ec38>] __sb_start_write+0xa8/0xd4
    [   23.531799]  #1:  (&of->mutex){+.+...}, at: [<c01d4b38>] kernfs_fop_write+0x54/0x1c0
    [   23.539916]  #2:  (s_active#52){++++.+}, at: [<c01d4b40>] kernfs_fop_write+0x5c/0x1c0
    [   23.548156]
    [   23.548156] stack backtrace:
    [   23.552734] CPU: 0 PID: 858 Comm: sh Not tainted 4.4.0-rc8-00025-gbbf360b #172
    [   23.560302] Hardware name: Generic OMAP4 (Flattened Device Tree)
    [   23.566589] Backtrace:
    [   23.569152] [<c00154d4>] (dump_backtrace) from [<c00156d0>] (show_stack+0x18/0x1c)
    [   23.577087]  r7:ed4b8570 r6:c0936400 r5:c07ae71c r4:00000000
    [   23.583038] [<c00156b8>] (show_stack) from [<c027e69c>] (dump_stack+0x98/0xc0)
    [   23.590606] [<c027e604>] (dump_stack) from [<c008a750>] (print_circular_bug+0x21c/0x33c)
    [   23.599090]  r5:c0939d60 r4:c0936400
    [   23.602874] [<c008a534>] (print_circular_bug) from [<c008e370>] (__lock_acquire+0x1c98/0x1d88)
    [   23.611877]  r10:00000003 r9:c0fd7a5c r8:ed4b8550 r7:ed4b8570 r6:ed4b8000 r5:c0ff69e4
    [   23.620117]  r4:c0936400 r3:ed4b8550
    [   23.623901] [<c008c6d8>] (__lock_acquire) from [<c008ed60>] (lock_acquire+0xe4/0x210)
    [   23.632080]  r10:00000000 r9:00000000 r8:60000013 r7:c07cb7b4 r6:00000001 r5:00000000
    [   23.640350]  r4:00000000
    [   23.643005] [<c008ec7c>] (lock_acquire) from [<c0530a30>] (mutex_lock_nested+0x74/0x450)
    [   23.651458]  r10:ecc0bf80 r9:edbe7dcc r8:ed4b8000 r7:c0fd7a5c r6:c0415d40 r5:00000000
    [   23.659729]  r4:c07cb780
    [   23.662384] [<c05309bc>] (mutex_lock_nested) from [<c0415d40>] (coresight_enable+0x1c/0x1b4)
    [   23.671234]  r10:ecc0bf80 r9:edbe7dcc r8:ed733c00 r7:00000000 r6:ed733c00 r5:00000002
    [   23.679473]  r4:ed762140
    [   23.682128] [<c0415d24>] (coresight_enable) from [<c0416030>] (enable_source_store+0x58/0x68)
    [   23.691070]  r7:00000000 r6:ed733c00 r5:00000002 r4:ed762160
    [   23.697052] [<c0415fd8>] (enable_source_store) from [<c030b358>] (dev_attr_store+0x20/0x2c)
    [   23.705780]  r5:edbe7dc0 r4:c0415fd8
    [   23.709533] [<c030b338>] (dev_attr_store) from [<c01d55e8>] (sysfs_kf_write+0x50/0x54)
    [   23.717834]  r5:edbe7dc0 r4:c030b338
    [   23.721618] [<c01d5598>] (sysfs_kf_write) from [<c01d4ba8>] (kernfs_fop_write+0xc4/0x1c0)
    [   23.730163]  r7:00000000 r6:00000000 r5:00000002 r4:edbe7dc0
    [   23.736145] [<c01d4ae4>] (kernfs_fop_write) from [<c015b60c>] (__vfs_write+0x34/0xe4)
    [   23.744323]  r10:00000000 r9:ecc0a000 r8:c0010964 r7:ecc0bf80 r6:00000002 r5:c01d4ae4
    [   23.752593]  r4:ee385a40
    [   23.755249] [<c015b5d8>] (__vfs_write) from [<c015bf38>] (vfs_write+0x98/0x174)
    [   23.762908]  r9:ecc0a000 r8:c0010964 r7:ecc0bf80 r6:000ab0d8 r5:00000002 r4:ee385a40
    [   23.771057] [<c015bea0>] (vfs_write) from [<c015c7a8>] (SyS_write+0x4c/0xa8)
    [   23.778442]  r8:c0010964 r7:00000002 r6:000ab0d8 r5:ee385a40 r4:ee385a40
    [   23.785522] [<c015c75c>] (SyS_write) from [<c00107c0>] (ret_fast_syscall+0x0/0x1c)
    [   23.793457]  r7:00000004 r6:00000001 r5:000ab0d8 r4:00000002
    [   23.799652] coresight-etb10 54162000.etb: ETB enabled
    [   23.805084] coresight-funnel 54164000.funnel: FUNNEL inport 0 enabled
    [   23.811859] coresight-replicator 44000000.ocp:replicator: REPLICATOR enabled
    [   23.819335] coresight-funnel 54158000.funnel: FUNNEL inport 0 enabled
    [   23.826110] coresight-etm3x 5414c000.ptm: ETM tracing enabled

The locking in coresight_unregister() is not required as the only customers of
the function are drivers themselves when an initialisation failure has been
encoutered.

Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-06 12:50:37 +02:00
prashantpaddune
3bca37f224 A750FXXU4CTBC 2020-03-27 21:51:54 +05:30