Adding smp_mb__after_lock define to be used as a smp_mb call after
a lock.
Making it nop for x86, since {read|write|spin}_lock() on x86 are
full memory barriers.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wrapped the smack_audit_data and selinux_audit_data
structs in include/linux/lsm_audit.h in ifdefs so that the
union will always be the correct size.
Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Made the lsm_priv union in include/linux/lsm_audit.h
anonymous.
Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Moved variable function in include/linux/lsm_audit.h into the
smack_audit_data struct since it is never used outside of it.
Also removed setting of function in the COMMON_AUDIT_DATA_INIT
macro because that variable is now private to SMACK.
Signed-off-by: Thomas Liu <tliu@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
I-dont-see-any-problems-with-it: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <jmorris@namei.org>
fix the following 'make includecheck' warning:
include/linux/rfkill.h: linux/types.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: gpio_mouse - use standard driver registration method
Input: mark serio and i8042 as suspended when hibernating too
Input: add support for generic GPIO-based matrix keypad
Input: arrange keyboards alphabetically
Input: gpio-keys - avoid possibility of sleeping in timer function
Input: gpio-keys - revert 'change timer to workqueue'
Input: dm355evm_keys - fix kconfig symbol names
Input: wacom - add DTF720a support and fix rotation on Intuos3
Input: i8042 - more reset quirks for MSI Wind-clone netbooks
Fix various silly problems wrt mnt_namespace.h:
- exit_mnt_ns() isn't used, remove it
- done that, sched.h and nsproxy.h inclusions aren't needed
- mount.h inclusion was need for vfsmount_lock, but no longer
- remove mnt_namespace.h inclusion from files which don't use anything
from mnt_namespace.h
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit a65e7bfcd7 broke the UML build with
the following error -
In file included from fs/proc/kcore.c:17:
include/linux/elfcore.h: In function 'elf_core_copy_task_regs':
include/linux/elfcore.h:129: error: implicit declaration of function 'task_pt_regs'
Fix this by restoring the previous behavior of returning 0 for all arches
like UML that don't define task_pt_regs.
Signed-off-by: Parag Warudkar <parag.lkml@gmail.com>
Acked-by: Amerigo Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clarify how the protocol version should be negotiated between kernel
and userspace. Notably libfuse didn't correctly handle the case when
the supported major versions didn't match.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Functions like free_bootmem() are allowed to free only part of a memory
block. This patch adds support for this via the kmemleak_free_part()
callback which removes the original object and creates one or two
additional objects as a result of the memory block split.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
The kmalloc_large() and kmalloc_large_node() functions were missed when
adding the kmemleak hooks to the slub allocator. However, they should be
traced to avoid false positives.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
This patch converts the ring buffers into a completely lockless
buffer recording system. The read side still takes locks since
we still serialize readers. But the writers are the ones that
must be lockless (those can happen in NMIs).
The main change is to the "head_page" pointer. We write to the
tail, and read from the head. The "head_page" pointer in the cpu
buffer is now just a reference to where to look. The real head
page is now kept in the head_page->list->prev->next pointer.
That is, in the list head of the previous page we set flags.
The list pages are allocated to be aligned such that the lowest
significant bits are always zero pointing to the list. This gives
us play to put in flags to their pointers.
bit 0: set when the page is a head page
bit 1: set when the writer is moving the page (for overwrite mode)
cmpxchg is used to update the pointer.
When the writer wraps the buffer and the tail meets the head,
in overwrite mode, the writer must move the head page forward.
It first uses cmpxchg to change the pointer flag from 1 to 2.
Once this is done, the reader on another CPU will not take the
page from the buffer.
The writers need to protect against interrupts (we don't bother with
disabling interrupts because NMIs are allowed to write too).
After the writer sets the pointer flag to 2, it takes care to
manage interrupts coming in. This is discribed in detail within the
comments of the code.
Changes in version 2:
- Let reader reset entries value of header page.
- Fix tail page passing commit page on reader page test.
- Always increment entries and write counter in rb_tail_page_update
- Add safety check in rb_set_commit_to_write to break out of infinite loop
- add mask in rb_is_reader_page
[ Impact: lock free writing to the ring buffer ]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
The practical values for these limits depend on the design of the
filesystem server so let userspace set them at initialization time.
Signed-off-by: Csaba Henk <csaba@gluster.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
sys_rt_tgsigqueueinfo needs to be declared in linux/syscalls.h so that
architectures defining the system call table in C can reference it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
LKML-Reference: <200907071023.44008.arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (39 commits)
Revert "p54: Use SKB list handling helpers instead of by-hand code."
sctp: fix warning at inet_sock_destruct() while release sctp socket
tun/tap: Fix crashes if open() /dev/net/tun and then poll() it.
dsa: fix 88e6xxx statistics counter snapshotting
forcedeth: Fix NAPI race.
drivers/net/smsc911x.c: Fix resource size off by 1 error
pcnet_cs: add new id
bnx2x: Fix the maximal values of coalescing timeouts.
bnx2x: Disable HC coalescing when setting timeout to zero.
tun: Fix device unregister race
be2net: fix spurious interrupt handling in intx mode
e1000e: disable K1 at 1000Mbps for 82577/82578
e1000e: delay second read of PHY_STATUS register on failure of first read
e1000e: prevent NVM corruption on sectors larger than 4K
e1000e: do not write SmartSpeed register bits on parts without support
e1000e: delay after LCD reset and proper checks for PHY configuration done
e1000e: PHY loopback broken on 82578
ixgbe: Not allow 8259x unsupported wol options change from ethtool
ixgbe: fix inconsistent SFP/SFP+ failure results.
ixgbe: fix regression on some 82598 adapters
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: Fix IRQ swizzling for ARI-enabled devices
ia64/PCI: adjust section annotation for pcibios_setup()
x86/PCI: get root CRS before scanning children
x86/PCI: fix boundary checking when using root CRS
PCI MSI: Fix restoration of MSI/MSI-X mask states in suspend/resume
PCI MSI: Unmask MSI if setup failed
PCI MSI: shorten PCI_MSIX_ENTRY_* symbol names
PCI: make pci_name() take const argument
PCI: More PATA quirks for not entering D3
PCI: fix kernel-doc warnings
PCI: check if bus has a proper bridge device before triggering SBR
PCI: remove pci_dac_dma_... APIs on mn10300
PCI ECRC: Remove unnecessary semicolons
PCI MSI: Return if alloc_msi_entry for MSI-X failed
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
ieee1394: sbp2: add support for disks >2 TB (and 16 bytes long CDBs)
firewire: sbp2: add support for disks >2 TB (and 16 bytes long CDBs)
firewire: core: do not DMA-map stack addresses
In include/linux/sysrq.h the constant EINVAL is being used but is undefined
if include/linux/errno.h is not included before.
Fix this by adding #include <linux/errno.h> at the beginning.
Signed-off-by: Tobias Doerffel <tobias.doerffel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the multithread program core thread message error.
This issue affects arches with neither has CORE_DUMP_USE_REGSET nor
ELF_CORE_COPY_TASK_REGS, ARM is one of them.
The thread message of core file is generated in elf_dump_thread_status.
The register values is set by elf_core_copy_task_regs in this function.
If an arch doesn't define ELF_CORE_COPY_TASK_REGS,
elf_core_copy_task_regs() will do nothing. Then the core file will not
have the register message of thread.
So add elf_core_copy_regs to set regiser values if ELF_CORE_COPY_TASK_REGS
doesn't define.
The following is how to reproduce this issue:
cat 1.c
#include <stdio.h>
#include <pthread.h>
#include <assert.h>
void td1(void * i)
{
while (1)
{
printf ("1\n");
sleep (1);
}
return;
}
void td2(void * i)
{
while (1)
{
printf ("2\n");
sleep (1);
}
return;
}
int
main(int argc,char *argv[],char *envp[])
{
pthread_t t1,t2;
pthread_create(&t1, NULL, (void*)td1, NULL);
pthread_create(&t2, NULL, (void*)td2, NULL);
sleep (10);
assert(0);
return (0);
}
arm-xxx-gcc -g -lpthread 1.c -o 1
copy 1.c and 1 to a arm board.
Goto this board.
ulimit -c 1800000
./1
# ./1
1
2
1
...
...
1
1: 1.c:37: main: Assertion `0' failed.
Aborted (core dumped)
Then you can get a core file.
gdb 1 core.xxx
Without the patch:
(gdb) info threads
3 process 909 0x00000000 in ?? ()
2 process 908 0x00000000 in ?? ()
* 1 process 907 0x4a6e2238 in raise () from /lib/libc.so.6
You can found that the pc of 909 and 908 is 0x00000000.
With the patch:
(gdb) info threads
3 process 885 0x4a749974 in nanosleep () from /lib/libc.so.6
2 process 884 0x4a749974 in nanosleep () from /lib/libc.so.6
* 1 process 883 0x4a6e2238 in raise () from /lib/libc.so.6
The pc of 885 and 884 is right.
Signed-off-by: Hui Zhu <teawater@gmail.com>
Cc: Amerigo Wang <xiyou.wangcong@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch allows a TIPC application to determine the number of messages
currently waiting in a socket's receive queue (TIPC_SOCK_RECVQ_DEPTH) or
in all TIPC socket receive queues (TIPC_NODE_RECVQ_DEPTH).
Signed-off-by: Oscar Medina <oscar.medina@motorola.com>
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
almost no users in the tree; and the few that use them treat them
like NET_RX_DROP.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The defines and typedefs (hw_interrupt_type, no_irq_type, irq_desc_t)
have been kept around for migration reasons. The last users are gone,
remove them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes:
kbuild: finally remove the obsolete variable $TOPDIR
gitignore: ignore scripts/ihex2fw
Kbuild: Disable the -Wformat-security gcc flag
gitignore: ignore gcov output files
kbuild: deb-pkg ship changelog
Add new __init_task_data macro to be used in arch init_task.c files.
asm-generic/vmlinux.lds.h: shuffle INIT_TASK* macro names in vmlinux.lds.h
Add new macros for page-aligned data and bss sections.
asm-generic/vmlinux.lds.h: Fix up RW_DATA_SECTION definition.
Large page first chunk allocator is primarily used for NUMA machines;
however, its NUMA handling is extremely simplistic. Regardless of
their proximity, each cpu is put into separate large page just to
return most of the allocated space back wasting large amount of
vmalloc space and increasing cache footprint.
This patch teachs NUMA details to large page allocator. Given
processor proximity information, pcpu_lpage_build_unit_map() will find
fitting cpu -> unit mapping in which cpus in LOCAL_DISTANCE share the
same large page and not too much virtual address space is wasted.
This greatly reduces the unit and thus chunk size and wastes much less
address space for the first chunk. For example, on 4/4 NUMA machine,
the original code occupied 16MB of virtual space for the first chunk
while the new code only uses 4MB - one 2MB page for each node.
[ Impact: much better space efficiency on NUMA machines ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Miller <davem@davemloft.net>
Currently cpu and unit are always identity mapped. To allow more
efficient large page support on NUMA and lazy allocation for possible
but offline cpus, cpu -> unit mapping needs to be non-linear and/or
sparse. This can be easily implemented by adding a cpu -> unit
mapping array and using it whenever looking up the matching unit for a
cpu.
The only unusal conversion is in pcpu_chunk_addr_search(). The passed
in address is unit0 based and unit0 might not be in use so it needs to
be converted to address of an in-use unit. This is easily done by
adding the unit offset for the current processor.
[ Impact: allows non-linear/sparse cpu -> unit mapping, no visible change yet ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
percpu core doesn't need to tack all the allocated pages. It needs to
know whether certain pages are populated and a way to reverse map
address to page when freeing. This patch drops pcpu_chunk->page[] and
use populated bitmap and vmalloc_to_page() lookup instead. Using
vmalloc_to_page() exclusively is also possible but complicates first
chunk handling, inflates cache footprint and prevents non-standard
memory allocation for percpu memory.
pcpu_chunk->page[] was used to track each page's allocation and
allowed asymmetric population which happens during failure path;
however, with single bitmap for all units, this is no longer possible.
Bite the bullet and rewrite (de)populate functions so that things are
done in clearly separated steps such that asymmetric population
doesn't happen. This makes the (de)population process much more
modular and will also ease implementing non-standard memory usage in
the future (e.g. large pages).
This makes @get_page_fn parameter to pcpu_setup_first_chunk()
unnecessary. The parameter is dropped and all first chunk helpers are
updated accordingly. Please note that despite the volume most changes
to first chunk helpers are symbol renames for variables which don't
need to be referenced outside of the helper anymore.
This change reduces memory usage and cache footprint of pcpu_chunk.
Now only #unit_pages bits are necessary per chunk.
[ Impact: reduced memory usage and cache footprint for bookkeeping ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Now that all first chunk allocator helpers allocate and map the first
chunk themselves, there's no need to have optional default alloc/map
in pcpu_setup_first_chunk(). Drop @populate_pte_fn and only leave
@dyn_size optional and make all other params mandatory.
This makes it much easier to follow what pcpu_setup_first_chunk() is
doing and what actual differences tweaking each parameter results in.
[ Impact: drop unused code path ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Generalize and move x86 setup_pcpu_lpage() into
pcpu_lpage_first_chunk(). setup_pcpu_lpage() now is a simple wrapper
around the generalized version. Other than taking size parameters and
using arch supplied callbacks to allocate/free/map memory,
pcpu_lpage_first_chunk() is identical to the original implementation.
This simplifies arch code and will help converting more archs to
dynamic percpu allocator.
While at it, factor out pcpu_calc_fc_sizes() which is common to
pcpu_embed_first_chunk() and pcpu_lpage_first_chunk().
[ Impact: code reorganization and generalization ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Generalize and move x86 setup_pcpu_4k() into pcpu_4k_first_chunk().
setup_pcpu_4k() now is a simple wrapper around the generalized
version. Other than taking size parameters and using arch supplied
callbacks to allocate/free memory, pcpu_4k_first_chunk() is identical
to the original implementation.
This simplifies arch code and will help converting more archs to
dynamic percpu allocator.
While at it, s/pcpu_populate_pte_fn_t/pcpu_fc_populate_pte_fn_t/ for
consistency.
[ Impact: code reorganization and generalization ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
The only extra feature @unit_size provides is making dead space at the
end of the first chunk which doesn't have any valid usecase. Drop the
parameter. This will increase consistency with generalized 4k
allocator.
James Bottomley spotted missing conversion for the default
setup_per_cpu_areas() which caused build breakage on all arcsh which
use it.
[ Impact: drop unused code path ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Ingo Molnar <mingo@elte.hu>
Pull linus#master to merge PER_CPU_DEF_ATTRIBUTES and alpha build fix
changes. As alpha in percpu tree uses 'weak' attribute instead of
inline assembly, there's no need for __used attribute.
Conflicts:
arch/alpha/include/asm/percpu.h
arch/mn10300/kernel/vmlinux.lds.S
include/linux/percpu-defs.h
This adds a new sysfs file called 'charge_type' which displays the
type of charging (unknown, n/a, trickle charge, or fast charging).
This allows things like battery diagnostics to determine what the
battery/EC is doing without resorting to changing the 'status' sysfs
output.
Signed-off-by: Andres Salomon <dilinger@collabora.co.uk>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: invalidation reverse calls
fuse: allow umask processing in userspace
fuse: fix bad return value in fuse_file_poll()
fuse: fix return value of fuse_dev_write()
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
cfq-iosched: remove redundant check for NULL cfqq in cfq_set_request()
blocK: Restore barrier support for md and probably other virtual devices.
block: get rid of queue-private command filter
block: Create bip slabs with embedded integrity vectors
cfq-iosched: get rid of the need for __GFP_NOFAIL in cfq_find_alloc_queue()
cfq-iosched: move cfqq initialization out of cfq_find_alloc_queue()
Trivial typo fixes in Documentation/block/data-integrity.txt.
The initial patches to support this through sysfs export were broken
and have been if 0'ed out in any release. So lets just kill the code
and reclaim some space in struct request_queue, if anyone would later
like to fixup the sysfs bits, the git history can easily restore
the removed bits.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch restores stacking ability to the block layer integrity
infrastructure by creating a set of dedicated bip slabs. Each bip slab
has an embedded bio_vec array at the end. This cuts down on memory
allocations and also simplifies the code compared to the original bvec
version. Only the largest bip slab is backed by a mempool. The pool is
contained in the bio_set so stacking drivers can ensure forward
progress.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@carl.(none)>
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (47 commits)
perf report: Add --symbols parameter
perf report: Add --comms parameter
perf report: Add --dsos parameter
perf_counter tools: Adjust only prelinked symbol's addresses
perf_counter: Provide a way to enable counters on exec
perf_counter tools: Reduce perf stat measurement overhead/skew
perf stat: Use percentages for scaling output
perf_counter, x86: Update x86_pmu after WARN()
perf stat: Micro-optimize the code: memcpy is only required if no event is selected and !null_run
perf stat: Improve output
perf stat: Fix multi-run stats
perf stat: Add -n/--null option to run without counters
perf_counter tools: Remove dead code
perf_counter: Complete counter swap
perf report: Print sorted callchains per histogram entries
perf_counter tools: Prepare a small callchain framework
perf record: Fix unhandled io return value
perf_counter tools: Add alias for 'l1d' and 'l1i'
perf-report: Add bare minimum PERF_EVENT_READ parsing
perf-report: Add modes for inherited stats and no-samples
...
Add a mutex to avoid a circular locking problem between the mm layer
semaphore and fbdev ioctl mutex through the fb_mmap() call.
Also, add mutex to all places where smem_start and smem_len fields change
so the mutex inside the fb_mmap() is actually used. Changing of these
fields before calling the framebuffer_register() are not mutexed.
This is 2.6.31 material. It removes one lockdep (fb_mmap() and
register_framebuffer()) but there is still another one (fb_release() and
register_framebuffer()). It also cleans up handling of the smem_start and
smem_len fields used by mutexed section of the fb_mmap().
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new spi_master.flags word listing constraints relevant to that
controller. Define the first constraint bit: a half duplex restriction.
Include that constraint in the OMAP1 MicroWire controller driver.
Have the mmc_spi host be the first customer of this flag. Its coding
relies heavily on full duplex transfers, so it must fail when the
underlying controller driver won't perform them.
(The spi_write_then_read routine could use it too: use the
temporarily-withdrawn full-duplex speedup unless this flag is set, in
which case the existing code applies. Similarly, any spi_master
implementing only SPI_3WIRE should set the flag.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add two new spi_device.mode bits to accomodate more protocol options, and
pass them through to usermode drivers:
* SPI_NO_CS ... a second 3-wire variant, where the chipselect
line is removed instead of a data line; transfers are still
full duplex.
This obviously has STRONG protocol implications since the
chipselect transitions can't be used to synchronize state
transitions with the SPI master.
* SPI_READY ... defines open drain signal that's pulled low
to pause the clock. This defines a 5-wire variant (normal
4-wire SPI plus READY) and two 4-wire variants (READY plus
each of the 3-wire flavors).
Such hardware flow control can be a big win. There are ADC
converters and flash chips that expose READY signals, but not
many host controllers support it today.
The spi_bitbang code should be changed to use SPI_NO_CS instead of its
current nonportable hack. That's a mode most hardware can easily support
(unlike SPI_READY).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: "Paulraj, Sandeep" <s-paulraj@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With ELF, at generating coredump, some more headers other than used
vmas are added.
When max_map_count == 65536, a core generated by following kinds of
code can be unreadable because the number of ELF's program header is
written in 16bit in Ehdr (please see elf.h) and the number overflows.
==
... = mmap(); (munmap, mprotect, etc...)
if (failed)
abort();
==
This can happen in mmap/munmap/mprotect/etc...which calls split_vma().
I think 65536 is not safe as _default_ and reduce it to 65530 is good
for avoiding unexpected corrupted core.
Anyway, max_map_count can be enlarged by sysctl if a user is brave..
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Jakub Jelinek <jakub@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
