Commit Graph

8 Commits

Author SHA1 Message Date
Wang Nan f094446390 coresight: fix kernel panic caused by invalid CPU
Commit d52c9750f1 ("coresight: reset "enable_sink" flag when need be")
caused a kernel panic because of the using of an invalid value: after
'for_each_cpu(cpu, mask)', value of local variable 'cpu' become invalid,
causes following 'cpu_to_node' access invalid memory area.

This patch brings the deleted 'cpu = cpumask_first(mask)' back.

Panic log:

 $ perf record -e cs_etm// ls

 Unable to handle kernel paging request at virtual address fffe801804af4f10
 pgd = ffff8017ce031600
 [fffe801804af4f10] *pgd=0000000000000000, *pud=0000000000000000
 Internal error: Oops: 96000004 [#1] SMP
 Modules linked in:
 CPU: 33 PID: 1619 Comm: perf Not tainted 4.7.1+ #16
 Hardware name: Huawei Taishan 2280 /CH05TEVBA, BIOS 1.10 11/24/2016
 task: ffff8017cb0c8400 ti: ffff8017cb154000 task.ti: ffff8017cb154000
 PC is at tmc_alloc_etf_buffer+0x60/0xd4
 LR is at tmc_alloc_etf_buffer+0x44/0xd4
 pc : [<ffff000008633df8>] lr : [<ffff000008633ddc>] pstate: 60000145
 sp : ffff8017cb157b40
 x29: ffff8017cb157b40 x28: 0000000000000000
 ...skip...
 7a60: ffff000008c64dc8 0000000000000006 0000000000000253 ffffffffffffffff
 7a80: 0000000000000000 0000000000000000 ffff0000080872cc 0000000000000001
 [<ffff000008633df8>] tmc_alloc_etf_buffer+0x60/0xd4
 [<ffff000008632b9c>] etm_setup_aux+0x1dc/0x1e8
 [<ffff00000816eed4>] rb_alloc_aux+0x2b0/0x338
 [<ffff00000816a5e4>] perf_mmap+0x414/0x568
 [<ffff0000081ab694>] mmap_region+0x324/0x544
 [<ffff0000081abbe8>] do_mmap+0x334/0x3e0
 [<ffff000008191150>] vm_mmap_pgoff+0xa4/0xc8
 [<ffff0000081a9a30>] SyS_mmap_pgoff+0xb0/0x22c
 [<ffff0000080872e4>] sys_mmap+0x18/0x28
 [<ffff0000080843f0>] el0_svc_naked+0x24/0x28
 Code: 912040a5 d0001c00 f873d821 911c6000 (b8656822)
 ---[ end trace 98933da8f92b0c9a ]---

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Xia Kaixu <xiakaixu@huawei.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Fixes: d52c9750f1 ("coresight: reset "enable_sink" flag when need be")
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: stable <stable@vger.kernel.org> # 4.10
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:46:42 +01:00
Quentin Lambert ec98960e0b coresight: perf: Add a missing call to etm_free_aux
Most error branches following the call to alloc_event_data contain a call
to etm_free_aux. This patch add a call to etm_free_aux to an error branch
that does not call it.

This issue was found with Hector.

Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29 20:05:32 +01:00
Mathieu Poirier d52c9750f1 coresight: reset "enable_sink" flag when need be
When using coresight from the perf interface sinks are specified
as part of the perf command line.  As such the sink needs to be
disabled once it has been acknowledged by the coresight framework.
Otherwise the sink stays enabled, which may interfere with other
sessions.

This patch removes the sink selection check from the build path
process and make it a function on it's own.  The function is
then used when operating from sysFS or perf to determine what
sink has been selected.

If operated from perf the status of the "enable_sink" flag is
reset so that concurrent session can use a different sink.  When
used from sysFS the status of the flag is left untouched since
users have full control.

The implementation doesn't handle a scenario where a sink has
been enabled from sysFS and another sink is selected from the
perf command line as both modes of operation are mutually
exclusive.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29 20:05:32 +01:00
Mathieu Poirier 8e67cdbc2f coresight: perf: deal with error condition properly
Function coresight_build_path() should return -ENOMEM when kzalloc
fails to allocated the requested memory.  That way callers can deal
with the error condition in a similar way.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-09 13:52:59 +02:00
Mathieu Poirier ca878b1466 coresight: etm-perf: configuring filters from perf core
This patch implements the required API needed to access
and retrieve range and start/stop filters from the perf core.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:05:43 +02:00
Mathieu Poirier 68905d73df coresight: etm-perf: pass struct perf_event to source::enable/disable()
With this commit [1] address range filter information is now found
in the struct hw_perf_event::addr_filters.  As such pass the event
itself to the coresight_source::enable/disable() functions so that
both event attribute and filter can be accessible for configuration.

[1] 'commit 375637bc52 ("perf/core: Introduce address range filtering")'

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:05:43 +02:00
Paul Gortmaker ca48fa22c3 drivers/hwtracing: make coresight-etm-perf.c explicitly non-modular
In commit 941943cf51 ("drivers/hwtracing:
make coresight-* explicitly non-modular") we removed all uses of
modular functions/macros in favour of their built-in equivlents in
this subsystem.

However that commit and commit 0bcbf2e30f
("coresight: etm-perf: new PMU driver for ETM tracers") were in flight
at the same time, and hence one new non-modular user of module_init
crept back in.  Fix it up like we did all the others.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-05 12:19:39 -08:00
Mathieu Poirier 0bcbf2e30f coresight: etm-perf: new PMU driver for ETM tracers
Perf is a well known and used tool for performance monitoring
and much more. A such it is an ideal candidate for integration
with coresight based HW tracing.

This patch introduces a PMU that represent a coresight tracer to
the Perf core.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20 14:11:01 -08:00