A secured user-space accessible pstore object. Writes
to /dev/pmsg0 are appended to the buffer, on reboot
the persistent contents are available in
/sys/fs/pstore/pmsg-ramoops-[ID].
One possible use is syslogd, or other daemon, can
write messages, then on reboot provides a means to
triage user-space activities leading up to a panic
as a companion to the pstore dmesg or console logs.
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
ramoops_pstore_read fails to return the next in a prz
series after first zero-sized entry, not venturing to
the next non-zero entry.
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
All previous checks will fail with error if memory size
is not sufficient to register a zone, so this legacy
check has become redundant.
Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes, just
removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There are
some ath9k patches coming in through this tree that have been acked by
the wireless maintainers as they relied on the debugfs changes.
Everything has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core update from Greg KH:
"Here's the set of driver core patches for 3.19-rc1.
They are dominated by the removal of the .owner field in platform
drivers. They touch a lot of files, but they are "simple" changes,
just removing a line in a structure.
Other than that, a few minor driver core and debugfs changes. There
are some ath9k patches coming in through this tree that have been
acked by the wireless maintainers as they relied on the debugfs
changes.
Everything has been in linux-next for a while"
* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
fs: debugfs: add forward declaration for struct device type
firmware class: Deletion of an unnecessary check before the function call "vunmap"
firmware loader: fix hung task warning dump
devcoredump: provide a one-way disable function
device: Add dev_<level>_once variants
ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
ath: use seq_file api for ath9k debugfs files
debugfs: add helper function to create device related seq_file
drivers/base: cacheinfo: remove noisy error boot message
Revert "core: platform: add warning if driver has no owner"
drivers: base: support cpu cache information interface to userspace via sysfs
drivers: base: add cpu_device_create to support per-cpu devices
topology: replace custom attribute macros with standard DEVICE_ATTR*
cpumask: factor out show_cpumap into separate helper function
driver core: Fix unbalanced device reference in drivers_probe
driver core: fix race with userland in device_add()
sysfs/kernfs: make read requests on pre-alloc files use the buffer.
sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
fs: sysfs: return EGBIG on write if offset is larger than file size
...
On some ARMs the memory can be mapped pgprot_noncached() and still
be working for atomic operations. As pointed out by Colin Cross
<ccross@android.com>, in some cases you do want to use
pgprot_noncached() if the SoC supports it to see a debug printk
just before a write hanging the system.
On ARMs, the atomic operations on strongly ordered memory are
implementation defined. So let's provide an optional kernel parameter
for configuring pgprot_noncached(), and use pgprot_writecombine() by
default.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robherring2@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: stable@vger.kernel.org
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
pstore compression/decompression was added during 3.12.
The ramoops driver prepends a "====timestamp.timestamp-C|D\n"
header to the compressed record before handing it over to pstore
driver which doesn't know about the header. In pstore_decompress(),
the pstore driver reads the first "==" as a zlib header, so the
decompression always fails. For example, this causes the driver
to write /dev/pstore/dmesg-ramoops-0.enc.z instead of
/dev/pstore/dmesg-ramoops-0.
This patch makes the ramoops driver remove the header before
pstore decompression.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In case that ramoops_init_przs failed, max_dump_cnt won't be reset to
zero in error handle path.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
ramoops_get_next_prz get the prz according the paramters. If it get a
uninitialized prz, access its members by following persistent_ram_old_size(prz)
will cause a NULL pointer crash.
Ex: if ftrace_size is 0, fprz will be NULL.
Fix it by return NULL in advance.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In ramoops_pstore_read, a valid prz pointer with zero size buffer will
break traverse of all persistent ram buffers. The latter buffer might be
lost.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Cc: Colin Cross <ccross@android.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
*_read_cnt in ramoops_context need to be cleared during pstore ->open to
support mutli times getting the records. The patch added missed
ftrace_read_cnt clearing and removed duplicate clearing in ramoops_probe.
Signed-off-by: Liu ShuoX <shuox.liu@intel.com>
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Previous attempt to fix was b042e47491
Suggested use of is_power_of_2() was bogus because is_power_of_2(0) is
false (documented behaviour).
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
In pstore write, add character 'C'(compressed) or 'D'(decompressed)
in the header while writing to Ram persistent buffer. In pstore read,
read the header and update the 'compressed' flag accordingly.
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Backends will set the flag 'compressed' after reading the log from
persistent store to indicate the data being returned to pstore is
compressed or not.
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Addition of new argument 'compressed' in the write call back will
help the backend to know if the data passed from pstore is compressed
or not (In case where compression fails.). If compressed, the backend
can add a tag indicating the data is compressed while writing to
persistent store.
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Pull powerpc updates from Ben Herrenschmidt:
"This is the powerpc changes for the 3.11 merge window. In addition to
the usual bug fixes and small updates, the main highlights are:
- Support for transparent huge pages by Aneesh Kumar for 64-bit
server processors. This allows the use of 16M pages as transparent
huge pages on kernels compiled with a 64K base page size.
- Base VFIO support for KVM on power by Alexey Kardashevskiy
- Wiring up of our nvram to the pstore infrastructure, including
putting compressed oopses in there by Aruna Balakrishnaiah
- Move, rework and improve our "EEH" (basically PCI error handling
and recovery) infrastructure. It is no longer specific to pseries
but is now usable by the new "powernv" platform as well (no
hypervisor) by Gavin Shan.
- I fixed some bugs in our math-emu instruction decoding and made it
usable to emulate some optional FP instructions on processors with
hard FP that lack them (such as fsqrt on Freescale embedded
processors).
- Support for Power8 "Event Based Branch" facility by Michael
Ellerman. This facility allows what is basically "userspace
interrupts" for performance monitor events.
- A bunch of Transactional Memory vs. Signals bug fixes and HW
breakpoint/watchpoint fixes by Michael Neuling.
And more ... I appologize in advance if I've failed to highlight
something that somebody deemed worth it."
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (156 commits)
pstore: Add hsize argument in write_buf call of pstore_ftrace_call
powerpc/fsl: add MPIC timer wakeup support
powerpc/mpic: create mpic subsystem object
powerpc/mpic: add global timer support
powerpc/mpic: add irq_set_wake support
powerpc/85xx: enable coreint for all the 64bit boards
powerpc/8xx: Erroneous double irq_eoi() on CPM IRQ in MPC8xx
powerpc/fsl: Enable CONFIG_E1000E in mpc85xx_smp_defconfig
powerpc/mpic: Add get_version API both for internal and external use
powerpc: Handle both new style and old style reserve maps
powerpc/hw_brk: Fix off by one error when validating DAWR region end
powerpc/pseries: Support compression of oops text via pstore
powerpc/pseries: Re-organise the oops compression code
pstore: Pass header size in the pstore write callback
powerpc/powernv: Fix iommu initialization again
powerpc/pseries: Inform the hypervisor we are using EBB regs
powerpc/perf: Add power8 EBB support
powerpc/perf: Core EBB support for 64-bit book3s
powerpc/perf: Drop MMCRA from thread_struct
powerpc/perf: Don't enable if we have zero events
...
Header size is needed to distinguish between header and the dump data.
Incorporate the addition of new argument (hsize) in the pstore write
callback.
Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There doesn't appear to be any reason for the overall pstore RAM buffer to
be a power of 2 size, so remove it. The individual console, ftrace and oops
buffers are still a power of 2 size.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
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Merge tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
Pull trivial pstore update from Tony Luck:
"Couple of pstore cleanups"
It turns out that the kmemdup() conversion ends up being undone by the
fact that the memory block also needed the ecc information (see commit
bd08ec33b5c2: "pstore/ram: Restore ecc information block"), so all that
remains after merging is the error return code change.
* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
pstore/ram: fix error return code in ramoops_probe()
fs: pstore: Replaced calls to kmalloc and memcpy with kmemdup
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
This was lost when proc/last_kmsg moved to pstore/console-ramoops.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
Replaced calls to kmalloc and memcpy with a single call to kmemdup. This
patch was found using coccicheck.
Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
Replaced calls to kmalloc and memcpy with a single call to kmemdup.
This patch was found using coccicheck.
Signed-off-by: Alexandru Gheorghiu <gheorghiuandru@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
The pstore RAM backend can get called during resume, and must be defensive
against a suspended time source. Expose getnstimeofday logic that returns
an error instead of a WARN. This can be detected and the timestamp can
be zeroed out.
Reported-by: Doug Anderson <dianders@chromium.org>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.
This change removes the use of __devinit from the pstore filesystem.
Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.
Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'for-v3.8' of git://git.infradead.org/users/cbou/linux-pstore
Pull pstore update from Anton Vorontsov:
"Here are just a few fixups for the pstore subsystem, nothing special
this time"
* tag 'for-v3.8' of git://git.infradead.org/users/cbou/linux-pstore:
pstore/ftrace: Adjust for ftrace_ops->func prototype change
pstore/ram: Fix bounds checks for mem_size, record_size, console_size and ftrace_size
pstore/ram: Fix undefined usage of rounddown_pow_of_two(0)
pstore/ram: Fixup section annotations
The bounds check in ramoops_init_prz was incorrect and ramoops_init_przs
had no check. Additionally, ramoops_init_przs allows record_size to be 0,
but ramoops_pstore_write_buf would always crash in this case.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
[Issue]
Currently, a variable name, which identifies each entry, consists of type, id and ctime.
But if multiple events happens in a short time, a second/third event may fail to log because
efi_pstore can't distinguish each event with current variable name.
[Solution]
A reasonable way to identify all events precisely is introducing a sequence counter to
the variable name.
The sequence counter has already supported in a pstore layer with "oopscount".
So, this patch adds it to a variable name.
Also, it is passed to read/erase callbacks of platform drivers in accordance with
the modification of the variable name.
<before applying this patch>
a variable name of first event: dump-type0-1-12345678
a variable name of second event: dump-type0-1-12345678
type:0
id:1
ctime:12345678
If multiple events happen in a short time, efi_pstore can't distinguish them because
variable names are same among them.
<after applying this patch>
it can be distinguishable by adding a sequence counter as follows.
a variable name of first event: dump-type0-1-1-12345678
a variable name of Second event: dump-type0-1-2-12345678
type:0
id:1
sequence counter: 1(first event), 2(second event)
ctime:12345678
In case of a write callback executed in pstore_console_write(), "0" is added to
an argument of the write callback because it just logs all kernel messages and
doesn't need to care about multiple events.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
[Issue]
Currently, a variable name, which is used to identify each log entry, consists of type,
id and ctime. But an erase callback does not use ctime.
If efi_pstore supported just one log, type and id were enough.
However, in case of supporting multiple logs, it doesn't work because
it can't distinguish each entry without ctime at erasing time.
<Example>
As you can see below, efi_pstore can't differentiate first event from second one without ctime.
a variable name of first event: dump-type0-1-12345678
a variable name of second event: dump-type0-1-23456789
type:0
id:1
ctime:12345678, 23456789
[Solution]
This patch adds ctime to an argument of an erase callback.
It works across reboots because ctime of pstore means the date that the record was originally stored.
To do this, efi_pstore saves the ctime to variable name at writing time and passes it to pstore
at reading time.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
record_size / console_size / ftrace_size can be 0 (this is how you disable
the feature), but rounddown_pow_of_two(0) is undefined. As suggested by
Kees Cook, use !is_power_of_2() as a condition to call
rounddown_pow_of_two and avoid its undefined behavior on the value 0. This
issue has been present since commit 1894a253 (ramoops: Move to
fs/pstore/ram.c).
Cc: stable@vger.kernel.org
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Florian Fainelli <ffainelli@freebox.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
The compiler complained about missing section annotations.
Fix it.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
We need to unregister platform device when module exit, this commit fixes
the issue.
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
write_buf() should be marked as notrace, otherwise it is prone to
recursion.
Though, yet the issue is never triggered in real life, because we run
inside the function tracer, where ftrace does its own recurse protection.
But it's still no good, plus soon we might switch to our own tracer ops,
and then the issue will be fatal. So, let's fix it.
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Fix printk format warning (on i386) in pstore:
fs/pstore/ram.c:409:3: warning: format '%lu' expects type 'long unsigned int', but argument 2 has type 'size_t'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
We can dereference 'cxt->cprz' if console and dump logging are disabled
(which is unlikely, but still possible to do). This patch fixes the issue
by changing the code so that we don't dereference przs at all, we can
just calculate bufsize from console_size and record_size values.
Plus, while at it, the patch improves the buffer size calculation.
After Kay's printk rework, we know the optimal buffer size for console
logging -- it is LOG_LINE_MAX (defined privately in printk.c). Previously,
if only console logging was enabled, we would allocate unnecessary large
buffer in pstore, while we only need LOG_LINE_MAX. (Pstore console logging
is still capable of handling buffers > LOG_LINE_MAX, it will just do
multiple calls to psinfo->write).
Note that I don't export the constant, since we will do even a better
thing soon: we will switch console logging to a new write_buf API, which
will eliminate the need for the additional buffer; and so we won't need
the constant.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
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>
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>
Don't use pstore.buf directly, instead convert the code to write_buf callback
which passes a pointer to a buffer as an argument.
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>
persistent_ram_new() returns ERR_PTR() value on errors, so during
freeing of the przs we should check for both NULL and IS_ERR() entries,
otherwise bad things will happen.
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>
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>
The console log size is configurable via ramoops.console_size
module option, and the log itself is available via
<pstore-mount>/console-ramoops file.
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>
This will help make code clearer when we'll add support for other
message types.
The patch also changes return value from -EINVAL to 0 in case of
end-of-records. The exact value doesn't matter for pstore (it should
be just <= 0), but 0 feels more correct.
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>
This will help make code clearer when we'll add support for other
message types.
This also makes probe() much shorter and understandable, plus
makes mem/record size checking a bit easier.
Implementation detail: we now use a paddr pointer, this will
be used for allocating persistent ram zones for other message
types.
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>
We're about to add support for other message types, so let's rename
some variables to not be confused later.
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>
Otherwise, unlinked file will reappear on the next boot.
Reported-by: Kees Cook <keescook@chromium.org>
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>
Without the update, we'll only see the new dmesg buffer after the
reboot, but previously we could see it right away. Making an oops
visible in pstore filesystem before reboot is a somewhat dubious
feature, but removing it wasn't an intentional change, so let's
restore it.
For this we have to make persistent_ram_save_old() safe for calling
multiple times, and also extern it.
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>
This is now straightforward: just introduce a module parameter and pass
the needed value to persistent_ram_new().
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Marco Stornelli <marco.stornelli@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mark Salyzyn