kernel.git/drivers/hwtracing/stm, branch linux-4.20.y

stm class: Fix a module refcount leak in policy creation error path

2019-01-13T08:24:08Z

commit c18614a1a11276837bdd44403d84d207c9951538 upstream. Commit c7fd62bc69d0 ("stm class: Introduce framing protocol drivers") adds a bug into the error path of policy creation, that would do a module_put() on a wrong module, if one tried to create a policy for an stm device which already has a policy, using a different protocol. IOW, | mkdir /config/stp-policy/dummy_stm.0:p_basic.test | mkdir /config/stp-policy/dummy_stm.0:p_sys-t.test # puts "p_basic" | mkdir /config/stp-policy/dummy_stm.0:p_sys-t.test # "p_basic" -> -1 throws: | general protection fault: 0000 [#1] SMP PTI | CPU: 3 PID: 2887 Comm: mkdir | RIP: 0010:module_put.part.31+0xe/0x90 | Call Trace: | module_put+0x13/0x20 | stm_put_protocol+0x11/0x20 [stm_core] | stp_policy_make+0xf1/0x210 [stm_core] | ? __kmalloc+0x183/0x220 | ? configfs_mkdir+0x10d/0x4c0 | configfs_mkdir+0x169/0x4c0 | vfs_mkdir+0x108/0x1c0 | do_mkdirat+0xe8/0x110 | __x64_sys_mkdir+0x1b/0x20 | do_syscall_64+0x5a/0x140 | entry_SYSCALL_64_after_hwframe+0x44/0xa9 Correct this sad mistake by calling calling 'put' on the correct reference, which happens to match another error path in the same function, so we consolidate the two at the same time. Signed-off-by: Alexander Shishkin Fixes: c7fd62bc69d0 ("stm class: Introduce framing protocol drivers") Reported-by: Ammy Yi Cc: stable Signed-off-by: Greg Kroah-Hartman

stm class: Use memcat_p()

2018-10-11T10:12:55Z

Instead of a local copy, use the memcat_p() helper to merge policy node attributes. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: heartbeat: Fix whitespace

2018-10-11T10:12:55Z

Fix whitespace in the code for better readability, no functional changes. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: p_sys-t: Add support for CLOCKSYNC packets

2018-10-11T10:12:54Z

This adds support for CLOCKSYNC SyS-T packets, that establish correlation between the transport clock (STP timestamps) and SyS-T timestamps. These packets are sent periodically to allow the decoder to keep both time sources in sync. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: Add MIPI SyS-T protocol support

2018-10-11T10:12:54Z

This adds support for MIPI SyS-T protocol as specified in an open standard [1]. In addition to marking message boundaries, it also supports tagging messages with the source UUID, to provide better distinction between trace sources, including payload length and timestamp in the message's metadata. This driver adds attributes to STP policy nodes to control/configure these metadata features. [1] https://www.mipi.org/specifications/sys-t Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: Switch over to the protocol driver

2018-10-11T10:12:54Z

Now that the default framing protocol is factored out into its own driver, switch over to using the driver for writing data. To that end, make the policy code require a valid protocol name (or absence thereof, which is equivalent to "p_basic"). Also, to make transition easier, make stm class request "p_basic" module at initialization time. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: Factor out default framing protocol

2018-10-11T10:12:54Z

The STP framing pattern that the stm class implicitly applies to the data payload is, in fact, a protocol. This patch moves the relevant code out of the stm core into its own driver module. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: Add a helper for writing data packets

2018-10-11T10:12:54Z

Add a helper to write a sequence of bytes as STP data packets. This is used by protocol drivers to output their metadata, as well as the actual data payload. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: Introduce framing protocol drivers

2018-10-11T10:12:54Z

At the moment, the stm class applies a certain STP framing pattern to the data as it is written to the underlying STM device. In order to allow different framing patterns (aka protocols), this patch introduces the concept of STP protocol drivers, defines data structures and APIs for the protocol drivers to use. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman

stm class: Clean up stp_configfs_init

2018-10-11T10:12:54Z

Minor code shortening, no functional changes. Signed-off-by: Alexander Shishkin Tested-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman