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2013-12-20pstore: Don't allow high traffic options on fragile devicesLuck, Tony1-2/+5
Some pstore backing devices use on board flash as persistent storage. These have limited numbers of write cycles so it is a poor idea to use them from high frequency operations. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-16pstore: Remove the messages related to compression failureAruna Balakrishnaiah1-4/+0
Remove the messages indicating compression failure as it will add to the space during panic path. Reported-by: Seiji Aguchi <seiji.aguchi@hds.com> Tested-by: Seiji Aguchi <seiji.aguchi@hds.com> Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-09-16pstore: Use zlib_inflateInit2 instead of zlib_inflateInitAruna Balakrishnaiah1-1/+1
Since zlib_deflateInit2() is used for specifying window bit during compression, zlib_inflateInit2() is appropriate for decompression. Reported-by: Seiji Aguchi <seiji.aguchi@hds.com> Tested-by: Seiji Aguchi <seiji.aguchi@hds.com> Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-09-16pstore: Adjust buffer size for compression for smaller registered buffersAruna Balakrishnaiah1-1/+22
When backends (ex: efivars) have smaller registered buffers, the big_oops_buf is too big for them as number of repeated occurences in the text captured will be less. What happens is that pstore takes too big a bite from the dmesg log and then finds it cannot compress it enough to meet the backend block size. Patch takes care of adjusting the buffer size based on the registered buffer size. cmpr values have been arrived after doing experiments with plain text for buffers of size 1k - 4k (Smaller the buffer size repeated occurence will be less) and with sample crash log for buffers ranging from 4k - 10k. Reported-by: Seiji Aguchi <seiji.aguchi@hds.com> Tested-by: Seiji Aguchi <seiji.aguchi@hds.com> Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-08-30pstore/ram: (really) fix undefined usage of rounddown_pow_of_twoMaxime Bizon1-3/+3
Previous attempt to fix was b042e47491ba5f487601b5141a3f1d8582304170 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>
2013-08-19pstore/ram: Read and write to the 'compressed' flag of pstoreAruna Balakrishnaiah1-8/+28
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>
2013-08-19pstore: Add file extension to pstore file if compressedAruna Balakrishnaiah3-6/+10
In case decompression fails, add a ".enc.z" to indicate the file has compressed data. This will help user space utilities to figure out the file contents. 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>
2013-08-19pstore: Add decompression support to pstoreAruna Balakrishnaiah1-2/+51
Based on the flag 'compressed' set or not, pstore will decompress the data returning a plain text file. If decompression fails for a particular record it will have the compressed data in the file which can be decompressed with 'openssl' command line tool. 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>
2013-08-19pstore: Introduce new argument 'compressed' in the read callbackAruna Balakrishnaiah2-2/+5
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>
2013-08-19pstore: Add compression support to pstoreAruna Balakrishnaiah1-9/+139
Add compression support to pstore which will help in capturing more data. Initially, pstore will make a call to kmsg_dump with a bigger buffer and will pass the size of bigger buffer to kmsg_dump and then compress the data to registered buffer of registered size. In case compression fails, pstore will capture the uncompressed data by making a call again to kmsg_dump with registered_buffer of registered size. Pstore will indicate the data is compressed or not with a flag in the write callback. 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>
2013-08-19pstore/Kconfig: Select ZLIB_DEFLATE and ZLIB_INFLATE when PSTORE is selectedAruna Balakrishnaiah1-0/+2
Pstore will make use of deflate and inflate algorithm to compress and decompress the data. So when Pstore is enabled select zlib_deflate and zlib_inflate. 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>
2013-08-19pstore: Add new argument 'compressed' in pstore write callbackAruna Balakrishnaiah2-4/+5
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>
2013-08-19pstore: d_alloc_name() doesn't return an ERR_PTRDan Carpenter1-2/+1
d_alloc_name() returns NULL on error. Also I changed the error code from -ENOSPC to -ENOMEM to reflect that we were short on RAM not disk space. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-07-04Merge branch 'next' of ↵Linus Torvalds4-6/+18
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 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 ...
2013-07-02pstore: Add hsize argument in write_buf call of pstore_ftrace_callAruna Balakrishnaiah1-1/+1
Incorporate the addition of hsize argument in write_buf callback of pstore. This was forgotten in 6bbbca735936e15b9431882eceddcf6dff76e03c pstore: Pass header size in the pstore write callback Causing a build failure when ftrace and pstore are enabled. Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01pstore: Pass header size in the pstore write callbackAruna Balakrishnaiah2-5/+8
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>
2013-06-28pstore: Return unique error if backend registration excluded by kernel paramLenny Szubowicz1-5/+6
This is patch 1/3 of a patch set that avoids what misleadingly appears to be a error during boot: ERST: Could not register with persistent store This message is displayed if the system has a valid ACPI ERST table and the pstore.backend kernel parameter has been used to disable use of ERST by pstore. But this same message is used for errors that preclude registration. As part of fixing this, return a unique error status from pstore_register if the pstore.backend kernel parameter selects a specific facility other than the requesting facility and check for this condition before any others. This allows the caller to distinquish this benign case from the other failure cases. Also, print an informational console message about which facility successfully registered as the pstore backend. Since there are various kernel parameters, config build options, and boot-time errors that can influence which facility registers with pstore, it's useful to have a positive indication. Signed-off-by: Lenny Szubowicz <lszubowi@redhat.com> Reported-by: Naotaka Hamaguchi <n.hamaguchi@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-06-25pstore: Fail to unlink if a driver has not defined pstore_eraseAruna Balakrishnaiah1-0/+2
pstore_erase is used to erase the record from the persistent store. So if a driver has not defined pstore_erase callback return -EPERM instead of unlinking a file as deleting the file without erasing its record in persistent store will give a wrong impression to customers. Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-06-20powerpc/pseries: Read common partition via pstoreAruna Balakrishnaiah1-0/+3
This patch exploits pstore subsystem to read details of common partition in NVRAM to a separate file in /dev/pstore. For instance, common partition details will be stored in a file named [common-nvram-6]. Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Reviewed-by: Jim Keniston <jkenisto@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/pseries: Read of-config partition via pstoreAruna Balakrishnaiah1-0/+3
This patch set exploits the pstore subsystem to read details of of-config partition in NVRAM to a separate file in /dev/pstore. For instance, of-config partition details will be stored in a file named [of-nvram-5]. Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Reviewed-by: Jim Keniston <jkenisto@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/pseries: Read rtas partition via pstoreAruna Balakrishnaiah1-0/+3
This patch set exploits the pstore subsystem to read details of rtas partition in NVRAM to a separate file in /dev/pstore. For instance, rtas details will be stored in a file named [rtas-nvram-4]. Signed-off-by: Aruna Balakrishnaiah <aruna@linux.vnet.ibm.com> Reviewed-by: Jim Keniston <jkenisto@us.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-14pstore/ram: remove the power of buffer size limitationRob Herring1-2/+0
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>
2013-06-14pstore/ram: avoid atomic accesses for ioremapped regionsRob Herring1-2/+52
For persistent RAM outside of main memory, the memory may have limitations on supported accesses. For internal RAM on highbank platform exclusive accesses are not supported and will hang the system. So atomic_cmpxchg cannot be used. This commit uses spinlock protection for buffer size and start updates on ioremapped regions instead. 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>
2013-05-09Merge tag 'please-pull-pstore' of ↵Linus Torvalds1-0/+2
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
2013-05-08pstore/ram: fix error return code in ramoops_probe()Wei Yongjun1-0/+2
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>
2013-04-03pstore/ram: Restore ecc information blockArve Hjønnevåg2-2/+13
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>
2013-04-03pstore/ram: Allow specifying ecc parameters in platform dataArve Hjønnevåg2-37/+42
Allow specifying ecc parameters in platform data Signed-off-by: Arve Hjønnevåg <arve@android.com> [jstultz: Tweaked commit subject & add commit message] Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Anton Vorontsov <anton@enomsg.org>
2013-04-03pstore/ram: Include ecc_size when calculating ecc_blockArve Hjønnevåg1-1/+2
Wastes less memory and allows using more memory for ecc than data. Signed-off-by: Arve Hjønnevåg <arve@android.com> [jstultz: Tweaked commit subject] Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Anton Vorontsov <anton@enomsg.org>
2013-03-18pstore: Replace calls to kmalloc and memcpy with kmemdupAlexandru Gheorghiu1-2/+1
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>
2013-03-11fs: pstore: Replaced calls to kmalloc and memcpy with kmemdupAlexandru Gheorghiu1-2/+1
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>
2013-02-21Merge tag 'please-pull-pstore' of ↵Linus Torvalds2-7/+46
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux Pull pstore patches from Tony Luck: "A few fixes to reduce places where pstore might hang a system in the crash path. Plus a new mountpoint (/sys/fs/pstore ... makes more sense then /dev/pstore)." Fix up trivial conflict in drivers/firmware/efivars.c * tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: pstore: Create a convenient mount point for pstore efi_pstore: Introducing workqueue updating sysfs efivars: Disable external interrupt while holding efivars->lock efi_pstore: Avoid deadlock in non-blocking paths pstore: Avoid deadlock in panic and emergency-restart path
2013-02-12pstore: Create a convenient mount point for pstoreJosh Boyer1-1/+17
Using /dev/pstore as a mount point for the pstore filesystem is slightly awkward. We don't normally mount filesystems in /dev/ and the /dev/pstore file isn't created automatically by anything. While this method will still work, we can create a persistent mount point in sysfs. This will put pstore on par with things like cgroups and efivarfs. Signed-off-by: Josh Boyer <jwboyer@redhat.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-02-04Merge branch 'fortglx/3.9/time' of git://git.linaro.org/people/jstultz/linux ↵Thomas Gleixner1-3/+7
into timers/core Trivial conflict in arch/x86/Kconfig Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-01-15time: create __getnstimeofday for WARNless callsKees Cook1-3/+7
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>
2013-01-11pstore: Avoid deadlock in panic and emergency-restart pathSeiji Aguchi1-6/+29
[Issue] When pstore is in panic and emergency-restart paths, it may be blocked in those paths because it simply takes spin_lock. This is an example scenario which pstore may hang up in a panic path: - cpuA grabs psinfo->buf_lock - cpuB panics and calls smp_send_stop - smp_send_stop sends IRQ to cpuA - after 1 second, cpuB gives up on cpuA and sends an NMI instead - cpuA is now in an NMI handler while still holding buf_lock - cpuB is deadlocked This case may happen if a firmware has a bug and cpuA is stuck talking with it more than one second. Also, this is a similar scenario in an emergency-restart path: - cpuA grabs psinfo->buf_lock and stucks in a firmware - cpuB kicks emergency-restart via either sysrq-b or hangcheck timer. And then, cpuB is deadlocked by taking psinfo->buf_lock again. [Solution] This patch avoids the deadlocking issues in both panic and emergency_restart paths by introducing a function, is_non_blocking_path(), to check if a cpu can be blocked in current path. With this patch, pstore is not blocked even if another cpu has taken a spin_lock, in those paths by changing from spin_lock_irqsave to spin_trylock_irqsave. In addition, according to a comment of emergency_restart() in kernel/sys.c, spin_lock shouldn't be taken in an emergency_restart path to avoid deadlock. This patch fits the comment below. <snip> /** * emergency_restart - reboot the system * * Without shutting down any hardware or taking any locks * reboot the system. This is called when we know we are in * trouble so this is our best effort to reboot. This is * safe to call in interrupt context. */ void emergency_restart(void) <snip> Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Acked-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-01-03pstore: remove __dev* attributes.Greg Kroah-Hartman2-13/+10
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>
2012-12-17lseek: the "whence" argument is called "whence"Andrew Morton1-3/+3
But the kernel decided to call it "origin" instead. Fix most of the sites. Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-15Merge tag 'for-v3.8' of git://git.infradead.org/users/cbou/linux-pstoreLinus Torvalds2-12/+34
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
2012-12-12pstore/ftrace: Adjust for ftrace_ops->func prototype changeAnton Vorontsov1-1/+3
This commit fixes the following warning: fs/pstore/ftrace.c:51:2: warning: initialization from incompatible pointer type [enabled by default] fs/pstore/ftrace.c:51:2: warning: (near initialization for ‘pstore_ftrace_ops.func’) [enabled by defaula Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-12-12pstore/ram: Fix bounds checks for mem_size, record_size, console_size and ↵Arve Hjønnevåg1-2/+16
ftrace_size 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>
2012-11-26efi_pstore: Add a sequence counter to a variable nameSeiji Aguchi4-14/+16
[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>
2012-11-26efi_pstore: Add ctime to argument of erase callbackSeiji Aguchi2-2/+3
[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>
2012-11-17pstore/ram: Fix undefined usage of rounddown_pow_of_two(0)Maxime Bizon1-4/+8
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>
2012-11-16pstore/ram: Fixup section annotationsHannes Reinecke1-5/+7
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>
2012-11-14pstore: Fix NULL pointer dereference in console writesColin Ian King1-1/+2
Passing a NULL id causes a NULL pointer deference in writers such as erst_writer and efi_pstore_write because they expect to update this id. Pass a dummy id instead. This avoids a cascade of oopses caused when the initial pstore_console_write passes a null which in turn causes writes to the console causing further oopses in subsequent pstore_console_write calls. Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-09-20pstore: Avoid recursive spinlocks in the oops_in_progress caseChuansheng Liu1-1/+7
Like 8250 driver, when pstore is registered as a console, to avoid recursive spinlocks when panic happening, change the spin_lock_irqsave to spin_trylock_irqsave when oops_in_progress is true. Signed-off-by: liu chuansheng <chuansheng.liu@intel.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-09-06pstore/ftrace: Convert to its own enable/disable debugfs knobAnton Vorontsov4-1/+103
With this patch we no longer reuse function tracer infrastructure, now we register our own tracer back-end via a debugfs knob. It's a bit more code, but that is the only downside. On the bright side we have: - Ability to make persistent_ram module removable (when needed, we can move ftrace_ops struct into a module). Note that persistent_ram is still not removable for other reasons, but with this patch it's just one thing less to worry about; - Pstore part is more isolated from the generic function tracer. We tried it already by registering our own tracer in available_tracers, but that way we're loosing ability to see the traces while we record them to pstore. This solution is somewhere in the middle: we only register "internal ftracer" back-end, but not the "front-end"; - When there is only pstore tracing enabled, the kernel will only write to the pstore buffer, omitting function tracer buffer (which, of course, still can be enabled via 'echo function > current_tracer'). Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-08-31pstore/ram: Add missing platform_device_unregisterJovi Zhang1-0/+1
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>
2012-08-04pstore/ram: Mark ramoops_pstore_write_buf() as notraceAnton Vorontsov1-6/+6
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>
2012-08-04pstore/ram: Fix printk format warningRandy Dunlap1-1/+1
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>