- 23 Mar, 2012 40 commits
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Denys Vlasenko authored
This can be used to close a few corner cases in strace where we get unwanted racy behavior after attach, but before we have a chance to set options (the notorious post-execve SIGTRAP comes to mind), and removes the need to track "did we set opts for this task" state in strace internals. While we are at it: Make it possible to extend SEIZE in the future with more functionality by passing non-zero 'addr' parameter. To that end, error out if 'addr' is non-zero. PTRACE_ATTACH did not (and still does not) have such check, and users (strace) do pass garbage there... let's avoid repeating this mistake with SEIZE. Set all task->ptrace bits in one operation - before this change, we were adding PT_SEIZED and PT_PTRACE_CAP with task->ptrace |= BIT ops. This was probably ok (not a bug), but let's be on a safer side. Changes since v2: use (unsigned long) casts instead of (long) ones, move PTRACE_SEIZE_DEVEL-related code to separate lines of code. Signed-off-by:
Denys Vlasenko <vda.linux@googlemail.com> Acked-by:
Tejun Heo <tj@kernel.org> Cc: Pedro Alves <palves@redhat.com> Reviewed-by:
Oleg Nesterov <oleg@redhat.com> Cc: Jan Kratochvil <jan.kratochvil@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Denys Vlasenko authored
Exchange PT_TRACESYSGOOD and PT_PTRACE_CAP bit positions, which makes PT_option bits contiguous and therefore makes code in ptrace_setoptions() much simpler. Every PTRACE_O_TRACEevent is defined to (1 << PTRACE_EVENT_event) instead of using explicit numeric constants, to ensure we don't mess up relationship between bit positions and event ids. PT_EVENT_FLAG_SHIFT was not particularly useful, PT_OPT_FLAG_SHIFT with value of PT_EVENT_FLAG_SHIFT-1 is easier to use. PT_TRACE_MASK constant is nuked, the only its use is replaced by (PTRACE_O_MASK << PT_OPT_FLAG_SHIFT). Signed-off-by:
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Denys Vlasenko authored
On ptrace(PTRACE_SETOPTIONS, pid, 0, <opts>), we used to set those option bits which are known, and then fail with -EINVAL if there are some unknown bits in <opts>. This is inconsistent with typical error handling, which does not change any state if input is invalid. This patch changes PTRACE_SETOPTIONS behavior so that in this case, we return -EINVAL and don't change any bits in task->ptrace. It's very unlikely that there is userspace code in the wild which will be affected by this change: it should have the form ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_BOGUSOPT) where PTRACE_O_BOGUSOPT is a constant unknown to the kernel. But kernel headers, naturally, don't contain any PTRACE_O_BOGUSOPTs, thus the only way userspace can use one if it defines one itself. I can't see why anyone would do such a thing deliberately. Signed-off-by: -
Oleg Nesterov authored
ptrace_event(PTRACE_EVENT_EXEC) sends SIGTRAP if PT_TRACE_EXEC is not set. This is because this SIGTRAP predates PTRACE_O_TRACEEXEC option, we do not need/want this with PT_SEIZED which can set the options during attach. Suggested-by:
Pedro Alves <palves@redhat.com> Signed-off-by:
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Oleg Nesterov authored
Another old/known problem. If the tracee is killed after it reports syscall_entry, it starts the syscall and debugger can't control this. This confuses the users and this creates the security problems for ptrace jailers. Change tracehook_report_syscall_entry() to return non-zero if killed, this instructs syscall_trace_enter() to abort the syscall. Reported-by:
Chris Evans <scarybeasts@gmail.com> Tested-by:
Indan Zupancic <indan@nul.nu> Signed-off-by:
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Namjae Jeon authored
Since '*outlen' is initialized to zero, it is currently possible to create a filename of length (FAT_LFN_LEN + 1) when utf8 is not enabled. To enforce the FAT_LFN_LEN limit, we must perform one less iteration. Signed-off-by:
Namjae Jeon <linkinjeon@gmail.com> Signed-off-by:
Ravishankar N <cyberax82@gmail.com> Acked-by:
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by:
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Namjae Jeon authored
xlate_to_uni() is called by vfat_build_slots() with sbi->nls_io as the final argument. nls_io can never be null at this point because the check is already being done in fat_fill_super() wherein the mount fails if it is null. Signed-off-by:
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Austin Boyle authored
Generalise NVRAM to support RAM with other size and offset, such as the 64 bytes of SRAM on the mcp7941x. [rdunlap@xenotime.net: fix printk format warning] Signed-off-by:
Austin Boyle <Austin.Boyle@aviatnet.com> Signed-off-by:
Wolfram Sang <w.sang@pengutronix.de> Signed-off-by:
Randy Dunlap <rdunlap@xenotime.net> Cc: David Anders <danders.dev@gmail.com> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by:
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David Anders authored
Do some cleanup of the comment sections as well as correct some formatting issues reported by checkpatch.pl. Signed-off-by:
David Anders <x0132446@ti.com> Signed-off-by:
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Wolfram Sang authored
No need to have two seperate if-blocks for setting up the irq. Signed-off-by:
David Anders <danders.dev@gmail.com> Cc: Austin Boyle <Austin.Boyle@aviatnet.com> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by:
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Wolfram Sang authored
The chip_desc table is suboptimal. Currently it requires an entry for every new chip type, even if it is empty. This has already been forgotten for the ds1388. Refactor the code, so new entries are only needed, when they chip type really needs a (non-empty) description. Also make the table visually more appealing. Signed-off-by:
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Ashish Jangam authored
RTC Driver for Dialog Semiconductor DA9052/53 PMICs. This patch is functionally tested on Samsung SMDKV6410. [akpm@linux-foundation.org: clean up file header layout, remove unneeded initialisation of local arrays] Signed-off-by:
David Dajun Chen <dchen@diasemi.com> Signed-off-by:
Ashish Jangam <ashish.jangam@kpitcummins.com> Cc: Paul Gortmaker <p_gortmaker@yahoo.com> Cc: David Dajun Chen <dchen@diasemi.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by:
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Kevin Liu authored
drivers/rtc/rtc-max8925.c: fix alarm->enabled mistake in max8925_rtc_read_alarm/max8925_rtc_set_alarm max8925_rtc_read_alarm() should set alrm->enabled based on both ALARM_IRQ_MASK and ALARM_CTRL setting. max8925_rtc_set_alarm() should enable/disable alarm according to ALARM_CTRL reg setting. Signed-off-by:
Kevin Liu <kliu5@marvell.com> Signed-off-by:
Haojian Zhuang <haojian.zhuang@marvell.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by:
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Kevin Liu authored
max8925_rtc_read_alarm should always return 0 with success Signed-off-by:
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Navin P authored
Signed-off-by:
Navin P <zicrim@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by:
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Yong Zhang authored
Since commit e58aa3d2 ("genirq: run irq handlers with interrupts disabled") we run all interrupt handlers with interrupts disabled and we even check and yell when an interrupt handler returns with interrupts enabled - see commit b738a50a ("genirq: warn when handler enables interrupts"). So now this flag is a NOOP and can be removed. Signed-off-by:
Yong Zhang <yong.zhang0@gmail.com> Acked-by:
Linus Walleij <linus.walleij@linaro.org> Acked-by:
Wan ZongShun <mcuos.com@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by:
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Venu Byravarasu authored
Following changes are made as part of this change: 1. As TWL RTC supports periodic interrupt, the correct event should be RTC_PF instead of RTC_UF. 2. No need to initialize variable "events" to 0 & then OR it with the event values. Hence fixing it. Signed-off-by:
Venu Byravarasu <vbyravarasu@nvidia.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by:
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Venu Byravarasu authored
For clearing RTC interrupt, programming ALARM bit only is sufficient, as all other bits are any way not affected by writing 0 to them. Hence removed unwanted OR operation. Signed-off-by:
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Venu Byravarasu authored
As part of probe, before enabling RTC, RTC_CTRL register is read to check if it is already running. If RTC is used by kernel alone, then this read is not required. Even if RTC was enabled already by boot loader, setting STOP_RTC bit again should not harm. Hence removed unwanted read operation. Signed-off-by:
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Venu Byravarasu authored
As the TWL RTC driver has a cached copy of enabled RTC interrupt bits in variable rtc_irq_bits, that can be checked before really setting or masking any of the interrupt bits. Signed-off-by:
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zhao zhang authored
Add RTC support(TOY counter0) for loongson1B SOC Signed-off-by:
zhao zhang <zhzhl555@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Ralf Baechle <ralf@linux-mips.org> Acked-by:
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Axel Lin authored
Factor out some boilerplate code for i2c driver registration into module_i2c_driver. Signed-off-by:
Axel Lin <axel.lin@gmail.com> Cc: Piotr Ziecik <kosmo@semihalf.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Scott Wood <scottwood@freescale.com> Cc: Srikanth Srinivasan <srikanth.srinivasan@freescale.com> Cc: Mike Rapoport <mike@compulab.co.il> Cc: Sergey Lapin <slapin@ossfans.org> Cc: Roman Fietze <roman.fietze@telemotive.de> Cc: Herbert Valerio Riedel <hvr@gnu.org> Cc: Alexander Bigga <ab@mycable.de> Cc: Dale Farnsworth <dale@farnsworth.org> Cc: Gregory Hermant <gregory.hermant@calao-systems.com> Cc: Wolfgang Grandegger <wg@grandegger.com> Cc: Martyn Welch <martyn.welch@ge.com> Cc: Byron Bradley <byron.bbradley@gmail.com> Signed-off-by:
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Axel Lin authored
Factor out some boilerplate code for spi driver registration into module_spi_driver. Signed-off-by:
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Viresh Kumar authored
rtc_device_register() calls rtc-spear routines internally. These routines call dev_get_drvdata() to get struct spear_rtc_config. Currently, platform_set_drvdata is called after rtc device is registered. This causes system to crash, as dev_get_drvdata returns NULL. For this we need to call platform_set_drvdata() before registering rtc device. This requires further cleanup, that leads to removal of dev_set_drvdata on rtc->dev, which was just not required at all. Also, we change the parameter to request_irq and pass pointer to config instead of pointer to rtc struct. This patch brings all above changes. Signed-off-by:
Viresh Kumar <viresh.kumar@st.com> Cc: Shiraz Hashim <shiraz.hashim@st.com> Cc: Deepak Sikri <deepak.sikri@st.com> Acked-by:
Rajeev Kumar <rajeev-dlh.kumar@st.com> Signed-off-by:
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Shiraz Hashim authored
Define API for '.alarm_irq_enable' to enable and disable alarm irq. This is required by the framework else RTC_AIE_ON and RTC_AIE_OFF ioctls return errors. Signed-off-by:
Shiraz Hashim <shiraz.hashim@st.com> Signed-off-by:
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Deepak Sikri authored
Handle the fix for unbalanced irq for the cases when enable_irq_wake fails, and a warning related to same is displayed on the console. The workaround is handled at the driver level. Signed-off-by:
Deepak Sikri <deepak.sikri@st.com> Signed-off-by:
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Bernhard Walle authored
Printing the error code makes it easier to debug the cause of a mount failure. For example I had the problem that the root file system could not be mounted read-writeable because my SD card was write-protected. Without an error code it looks like the SD card was not detected at all. Signed-off-by:
Bernhard Walle <bernhard@bwalle.de> Signed-off-by:
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Diwakar Tundlam authored
Otherwise the 'Calibration skipped' message gets printed everytime a CPU is hotplugged in, cluttering console for systems that frequently hotplug CPUs. Signed-off-by:
Diwakar Tundlam <dtundlam@nvidia.com> Cc: Phil Carmody <ext-phil.2.carmody@nokia.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Greg KH <greg@kroah.com> Cc: Sameer Nanda <snanda@chromium.org> Cc: Peter De Schrijver <pdeschrijver@nvidia.com> Signed-off-by:
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Dan Carpenter authored
We never use the length variable. Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Acked-by:
Jason Baron <jbaron@redhat.com> Signed-off-by:
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Steven Rostedt authored
Looking for a bug in -rt, I stumbled across this code here from: commit 2dfa4eea ("epoll keyed wakeups: teach epoll about hints coming with the wakeup key"), specifically: #ifdef CONFIG_DEBUG_LOCK_ALLOC static inline void ep_wake_up_nested(wait_queue_head_t *wqueue, unsigned long events, int subclass) { unsigned long flags; spin_lock_irqsave_nested(&wqueue->lock, flags, subclass); wake_up_locked_poll(wqueue, events); spin_unlock_irqrestore(&wqueue->lock, flags); } #else static inline void ep_wake_up_nested(wait_queue_head_t *wqueue, unsigned long events, int subclass) { wake_up_poll(wqueue, events); } #endif You change the function of ep_wake_up_nested() depending on whether CONFIG_DEBUG_LOCK_ALLOC is set or not. This looks awfully suspicious, and there's no comment to explain why. I initially thought that this was trying to fool lockdep, and hiding a real bug. Investigating it, I found the creation of wake_up_nested() (which no longer exists) but was created for the sole purpose of epoll and its strange wake ups, as explained in commit 0ccf831c ("lockdep: annotate epoll") Although the commit message says "annotate epoll" the change log is much better at explaining what is happening than what is in the actual code. Thus a comment is really necessary here. And to save the time of other developers from having to go trudging through the git logs trying to figure out why this code exists. I took parts of the change log and placed it into a comment above the affected code. This will make the description of what is happening more visible to new developers that have to look at this code for the first time. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Signed-off-by:
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Hans Verkuil authored
In some cases the poll() implementation in a driver has to do different things depending on the events the caller wants to poll for. An example is when a driver needs to start a DMA engine if the caller polls for POLLIN, but doesn't want to do that if POLLIN is not requested but instead only POLLOUT or POLLPRI is requested. This is something that can happen in the video4linux subsystem among others. Unfortunately, the current epoll/poll/select implementation doesn't provide that information reliably. The poll_table_struct does have it: it has a key field with the event mask. But once a poll() call matches one or more bits of that mask any following poll() calls are passed a NULL poll_table pointer. Also, the eventpoll implementation always left the key field at ~0 instead of using the requested events mask. This was changed in eventpoll.c so the key field now contains the actual events that should be polled for as set by the caller. The solution to the NULL poll_table pointer is to set the qproc field to NULL in poll_table once poll() matches the events, not the poll_table pointer itself. That way drivers can obtain the mask through a new poll_requested_events inline. The poll_table_struct can still be NULL since some kernel code calls it internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h). In that case poll_requested_events() returns ~0 (i.e. all events). Very rarely drivers might want to know whether poll_wait will actually wait. If another earlier file descriptor in the set already matched the events the caller wanted to wait for, then the kernel will return from the select() call without waiting. This might be useful information in order to avoid doing expensive work. A new helper function poll_does_not_wait() is added that drivers can use to detect this situation. This is now used in sock_poll_wait() in include/net/sock.h. This was the only place in the kernel that needed this information. Drivers should no longer access any of the poll_table internals, but use the poll_requested_events() and poll_does_not_wait() access functions instead. In order to enforce that the poll_table fields are now prepended with an underscore and a comment was added warning against using them directly. This required a change in unix_dgram_poll() in unix/af_unix.c which used the key field to get the requested events. It's been replaced by a call to poll_requested_events(). For qproc it was especially important to change its name since the behavior of that field changes with this patch since this function pointer can now be NULL when that wasn't possible in the past. Any driver accessing the qproc or key fields directly will now fail to compile. Some notes regarding the correctness of this patch: the driver's poll() function is called with a 'struct poll_table_struct *wait' argument. This pointer may or may not be NULL, drivers can never rely on it being one or the other as that depends on whether or not an earlier file descriptor in the select()'s fdset matched the requested events. There are only three things a driver can do with the wait argument: 1) obtain the key field: events = wait ? wait->key : ~0; This will still work although it should be replaced with the new poll_requested_events() function (which does exactly the same). This will now even work better, since wait is no longer set to NULL unnecessarily. 2) use the qproc callback. This could be deadly since qproc can now be NULL. Renaming qproc should prevent this from happening. There are no kernel drivers that actually access this callback directly, BTW. 3) test whether wait == NULL to determine whether poll would return without waiting. This is no longer sufficient as the correct test is now wait == NULL || wait->_qproc == NULL. However, the worst that can happen here is a slight performance hit in the case where wait != NULL and wait->_qproc == NULL. In that case the driver will assume that poll_wait() will actually add the fd to the set of waiting file descriptors. Of course, poll_wait() will not do that since it tests for wait->_qproc. This will not break anything, though. There is only one place in the whole kernel where this happens (sock_poll_wait() in include/net/sock.h) and that code will be replaced by a call to poll_does_not_wait() in the next patch. Note that even if wait->_qproc != NULL drivers cannot rely on poll_wait() actually waiting. The next file descriptor from the set might match the event mask and thus any possible waits will never happen. Signed-off-by:
Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by:
Jonathan Corbet <corbet@lwn.net> Reviewed-by:
Al Viro <viro@zeniv.linux.org.uk> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by:
Hans de Goede <hdegoede@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by:
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Darrick J. Wong authored
Allow the kernel builder to choose a crc32* algorithm for the kernel. Signed-off-by:
Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by:
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Darrick J. Wong authored
Add self-test code for crc32c. Signed-off-by:
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Darrick J. Wong authored
Since lib/crc32.c now provides crc32c, remove the software implementation here and call the library function instead. Signed-off-by:
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Darrick J. Wong authored
Reuse the existing crc32 code to stamp out a crc32c implementation. Signed-off-by:
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Bob Pearson authored
Add a comment at the top of crc32.c [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by:
Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by:
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Bob Pearson authored
Add two changes that improve the performance of x86 systems 1. replace main loop with incrementing counter this change improves the performance of the selftest by about 5-6% on Nehalem CPUs. The apparent reason is that the compiler can use the loop index to perform an indexed memory access. This is reported to make the performance of PowerPC CPUs to get worse. 2. replace the rem_len loop with incrementing counter this change improves the performance of the selftest, which has more than the usual number of occurances, by about 1-2% on x86 CPUs. In actual work loads the length is most often a multiple of 4 bytes and this code does not get executed as often if at all. Again this change is reported to make the performance of PowerPC get worse. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by:
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Bob Pearson authored
Add slicing-by-8 algorithm to the existing slicing-by-4 algorithm. This consists of: - extend largest BITS size from 32 to 64 - extend tables from tab[4][256] to up to tab[8][256] - Add code for inner loop. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by:
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Bob Pearson authored
crc32.c provides a choice of one of several algorithms for computing the LSB and LSB versions of the CRC32 checksum based on the parameters CRC_LE_BITS and CRC_BE_BITS. In the original version the values 1, 2, 4 and 8 respectively selected versions of the alrogithm that computed the crc 1, 2, 4 and 32 bits as a time. This patch series adds a new version that computes the CRC 64 bits at a time. To make things easier to understand the parameter has been reinterpreted to actually stand for the number of bits processed in each step of the algorithm so that the old value 8 has been replaced with the value 32. This also allows us to add in a widely used crc algorithm that computes the crc 8 bits at a time called the Sarwate algorithm. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by:
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Bob Pearson authored
crc32.c in its original version freely mixed u32, __le32 and __be32 types which caused warnings from sparse with __CHECK_ENDIAN__. This patch fixes these by forcing the types to u32. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by:
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