Decoding the binary trace w/ a different kernel might be troublesome
since we convert addresses to symbols. For kernels with minimal changes,
the mappings would probably match, but it's not guaranteed at all.
(But still we could convert the addresses by hand, since we do print
raw addresses.)
If we use modules, the symbols could be loaded at different addresses
from the previously booted kernel, and so this would also fail, but
there's nothing we can do about it.
Also, the binary data format that pstore/ram is using in its ringbuffer
may change between the kernels, so here we too must ensure that we're
running the same kernel.
So, there are two questions really:
1. How to compute the unique kernel tag;
2. Where to store it.
In this patch we're using LINUX_VERSION_CODE, just as hibernation
(suspend-to-disk) does. This way we are protecting from the kernel
version mismatch, making sure that we're running the same kernel
version and patch level. We could use CRC of a symbol table (as
suggested by Tony Luck), but for now let's not be that strict.
And as for storing, we are using a small trick here. Instead of
allocating a dedicated buffer for the tag (i.e. another prz), or
hacking ram_core routines to "reserve" some control data in the
buffer, we are just encoding the tag into the buffer signature
(and XOR'ing it with the actual signature value, so that buffers
not needing a tag can just pass zero, which will result into the
plain old PRZ signature).
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Suggested-by: Tony Luck <tony.luck@intel.com>
Suggested-by: Colin Cross <ccross@android.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Headers should really include all the needed prototypes, types, defines
etc. to be self-contained. This is a long-standing issue, but apparently
the new tracing code unearthed it (SMP=n is also a prerequisite):
In file included from fs/pstore/internal.h:4:0,
from fs/pstore/ftrace.c:21:
include/linux/pstore.h:43:15: error: field ‘read_mutex’ has incomplete type
While at it, I also added the following:
linux/types.h -> size_t, phys_addr_t, uXX and friends
linux/spinlock.h -> spinlock_t
linux/errno.h -> Exxxx
linux/time.h -> struct timespec (struct passed by value)
struct module and rs_control forward declaration (passed via pointers).
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ftrace log size is configurable via ramoops.ftrace_size
module option, and the log itself is available via
<pstore-mount>/ftrace-ramoops file.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With this support kernel can save function call chain log into a
persistent ram buffer that can be decoded and dumped after reboot
through pstore filesystem. It can be used to determine what function
was last called before a reset or panic.
We store the log in a binary format and then decode it at read time.
p.s.
Mostly the code comes from trace_persistent.c driver found in the
Android git tree, written by Colin Cross <ccross@android.com>
(according to sign-off history). I reworked the driver a little bit,
and ported it to pstore.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For function tracing we need to stop using pstore.buf directly, since
in a tracing callback we can't use spinlocks, and thus we can't safely
use the global buffer.
With write_buf callback, backends no longer need to access pstore.buf
directly, and thus we can pass any buffers (e.g. allocated on stack).
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is now pretty straightforward: instead of using bool, just pass
an integer. For backwards compatibility ramoops.ecc=1 means 16 bytes
ECC (using 1 byte for ECC isn't much of use anyway).
Suggested-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The struct members were never used anywhere outside of
persistent_ram_init_ecc(), so there's actually no need for them
to be in the struct.
If we ever want to make polynomial or symbol size configurable,
it would make more sense to just pass initialized rs_decoder
to the persistent_ram init functions.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add iio channel type and modifiers for Correlated Color Temperature (CCT)
and RGBC (red/green/blue/clear) data.
Add CCT and RGBC descriptions to documentation.
Changes:
Revised/condensed RGBC descriptions.
Merge and trivial fix done by Jonathan Cameron.
Signed-off-by: Jon Brenner <jbrenner@taosinc.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add a helper function for validating a scan mask for devices where exactly one
channel must be selected during sampling. This is a common case among devices
which have scan mask restrictions so it makes sense to provide this function in
the core.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This is useful for cases where the number of valid scan masks grows
exponentially, but it is rather easy to check whether a mask is valid or not
programmatically.
An example of such a case is a device with multiple ADCs where each ADC has a
upstream MUX, which allows to select from a number of physical channels.
+-------+ +-------+
| | | | --- Channel 1
| ADC 1 |---| MUX 1 | --- ...
| | | | --- Channel M
+-------+ +-------+
. . .
. . .
. . .
+-------+ +-------+
| | | | --- Channel M * N + 1
| ADC N |---| MUX N | --- ...
| | | | --- Channel M * N + M
+-------+ +-------+
The number of necessary scan masks for this case is (M+1)**N - 1, on the other
hand it is easy to check whether subsets for each ADC of the scanmask have only
one bit set.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
There will probably be a number of such modifiers eventually but
this one is used in the adis16240 accelerometer driver.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
There will probably be a number of such modifiers eventually but
this one is used in the adis16204 accelerometer driver.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
These were originally introduced when the plan was to have parallel
IIO cores in and out of staging with a slow move between them.
Now we have reached the point where the whole core has moved,
they need clearing up!
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch adds support for the Analog Devices AD7265 and AD7266
Analog-to-Digital converters.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This picks up the staging changes made in 3.5-rc4 so that everyone can sync up
properly.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull drm fixes from Dave Airlie:
"Nothing major in here, one radeon SI fix for tiling, and one uninit
var fix, two minor header file fixes."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm: drop comment about this header being autogenerated.
drm/edid: don't return stack garbage from supports_rb
vga_switcheroo: Add include guard
drm/radeon: SI tiling fixes for display
Pull perf updates from Ingo Molnar.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ftrace: Make all inline tags also include notrace
perf: Use css_tryget() to avoid propping up css refcount
perf tools: Fix synthesizing tracepoint names from the perf.data headers
perf stat: Fix default output file
perf tools: Fix endianity swapping for adds_features bitmask
Pull NFS client bugfixes from Trond Myklebust:
- Fix a write hang due to an uninitalised variable when
!defined(CONFIG_NFS_V4)
- Address upcall races in the legacy NFSv4 idmapper
- Remove an O_DIRECT refcounting issue
- Fix a pNFS refcounting bug when the file layout metadata server is
also acting as a data server
- Fix a pNFS module loading race.
* tag 'nfs-for-3.5-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFS: Force the legacy idmapper to be single threaded
NFS: Initialise commit_info.rpc_out when !defined(CONFIG_NFS_V4)
NFS: Fix a refcounting issue in O_DIRECT
NFSv4.1: Fix a race in set_pnfs_layoutdriver
NFSv4.1: Fix umount when filelayout DS is also the MDS
Registering the platform driver before module_init allows us to log oopses
that happen during device probing.
This requires changing module_init to postcore_initcall, and switching
from platform_driver_probe to platform_driver_register because the
platform device is not registered when the platform driver is registered;
and because we use driver_register, now can't use create_bundle() (since
it will try to register the same driver once again), so we have to switch
to platform_device_register_data().
Also, some __init -> __devinit changes were needed.
Overall, the registration logic is now much clearer, since we have only
one driver registration point, and just an optional dummy device, which
is created from the module parameters.
Suggested-by: Colin Cross <ccross@android.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull staging tree fixes from Greg Kroah-Hartman:
"Here are a number of small fixes for the drivers/staging tree, as well
as iio and pstore drivers (which came from the staging tree in the
3.5-rc1 merge). All of these are tiny, but resolve issues that people
have been reporting.
There's also a documentation update to reflect what the iio drivers
really are doing, which is good to get straightened out.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'staging-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: r8712u: Add new USB IDs
staging: gdm72xx: Release netlink socket properly
iio: drop wrong reference from Kconfig
pstore/inode: Make pstore_fill_super() static
pstore/ram: Should zap persistent zone on unlink
pstore/ram_core: Factor persistent_ram_zap() out of post_init()
pstore/ram_core: Do not reset restored zone's position and size
pstore/ram: Should update old dmesg buffer before reading
staging:iio:ad7298: Fix linker error due to missing IIO kfifo buffer
Revert "staging: usbip: bugfix for stack corruption on 64-bit architectures"
staging: usbip: bugfix for stack corruption on 64-bit architectures
staging/comedi: fix build for USB not enabled
staging: omapdrm: fix crash when freeing bad fb
staging:iio:ad7606: Re-add missing scale attribute
iio: Fix potential use after free
staging:iio: remove num_interrupt_lines from documentation
iio: documentation: Add out_altvoltage and friends
Pull driver core and printk fixes from Greg Kroah-Hartman:
"Here are some fixes for 3.5-rc4 that resolve the kmsg problems that
people have reported showing up after the printk and kmsg changes went
into 3.5-rc1. There are also a smattering of other tiny fixes for the
extcon and hyper-v drivers that people have reported.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'driver-core-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
extcon: max8997: Add missing kfree for info->edev in max8997_muic_remove()
extcon: Set platform drvdata in gpio_extcon_probe() and fix irq leak
extcon: Fix wrong index in max8997_extcon_cable[]
kmsg - kmsg_dump() fix CONFIG_PRINTK=n compilation
printk: return -EINVAL if the message len is bigger than the buf size
printk: use mutex lock to stop syslog_seq from going wild
kmsg - kmsg_dump() use iterator to receive log buffer content
vme: change maintainer e-mail address
Extcon: Don't try to create duplicate link names
driver core: fixup reversed deferred probe order
printk: Fix alignment of buf causing crash on ARM EABI
Tools: hv: verify origin of netlink connector message
