32bit wrapper is lost on that; 64bit one is *not*, since
we need to arrange for full pt_regs on stack when we call
sys_execve() and we need to load callee-saved ones from
there afterwards.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... no need to read current_thread_info()->task only to
feed it to task_thread_page() immediately afterwards.
Moreover, not using current_thread_info() at all ends
up with better assembler - we need a location very close
to the top of kernel stack page and it's actually better
to do or with 0x1fff, followed be subtracting a small
constant than and with ~0x1fff, followed by adding a large
one. Both & and | would be a couple of insns (mvn lsr/mvn lsl
for |, a pair of bic for &), but the following addition
would cost a pair of add while the subtraction ends up
as a single sub.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Selected by __ARCH_WANT_SYS_EXECVE in unistd.h. Requires
* working current_pt_regs()
* *NOT* doing a syscall-in-kernel kind of kernel_execve()
implementation. Using generic kernel_execve() is fine.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Otherwise, we got NULL derefernce while calling backlight_device_unregister()
in tps65217_bl_remove().
Also convert to use module_platform_driver.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Patch 6e20a0a4 "gpio: pcf857x: enable gpio_to_irq() support"
added IRQ domain support to the pcf857x driver, but some configurations
(e.g. davinci_all_defconfig) don't already enable CONFIG_IRQ_DOMAIN.
Always selecting it from the Kconfig in this case is what other
such drivers do as well, and avoids these build errors:
Without this patch, building davinci_all_defconfig results in:
drivers/gpio/gpio-pcf857x.c: In function 'pcf857x_to_irq':
drivers/gpio/gpio-pcf857x.c:167:2: error: implicit declaration of function 'irq_create_mapping'
drivers/gpio/gpio-pcf857x.c: In function 'pcf857x_irq_demux_work':
drivers/gpio/gpio-pcf857x.c:183:3: error: implicit declaration of function 'irq_find_mapping'
drivers/gpio/gpio-pcf857x.c: In function 'pcf857x_irq_domain_cleanup':
drivers/gpio/gpio-pcf857x.c:218:3: error: implicit declaration of function 'irq_domain_remove'
drivers/gpio/gpio-pcf857x.c: In function 'pcf857x_irq_domain_init':
drivers/gpio/gpio-pcf857x.c:230:2: error: implicit declaration of function 'irq_domain_add_linear'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
based mostly on arm and alpha versions. Architectures can define
__ARCH_WANT_KERNEL_EXECVE and use it, provided that
* they have working current_pt_regs(), even for kernel threads.
* kernel_thread-spawned threads do have space for pt_regs
in the normal location. Normally that's as simple as switching to
generic kernel_thread() and making sure that kernel threads do *not*
go through return from syscall path; call the payload from equivalent
of ret_from_fork if we are in a kernel thread (or just have separate
ret_from_kernel_thread and make copy_thread() use it instead of
ret_from_fork in kernel thread case).
* they have ret_from_kernel_execve(); it is called after
successful do_execve() done by kernel_execve() and gets normal
pt_regs location passed to it as argument. It's essentially
a longjmp() analog - it should set sp, etc. to the situation
expected at the return for syscall and go there. Eventually
the need for that sucker will disappear, but that'll take some
surgery on kernel_thread() payloads.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Normally (and that's the default) it's just task_pt_regs(current).
However, if an architecture can optimize that, it can do so by
making a macro of its own available from asm/ptrace.h. More
importantly, some architectures have task_pt_regs() working only
for traced tasks blocked on signal delivery. current_pt_regs()
needs to work for *all* processes, so before those architectures
start using stuff relying on current_pt_regs() they'll need a
properly working variant.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Let architectures select GENERIC_KERNEL_THREAD and have their copy_thread()
treat NULL regs as "it came from kernel_thread(), sp argument contains
the function new thread will be calling and stack_size - the argument for
that function". Switching the architectures begins shortly...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
copy_from_user() returns the number of bytes remaining to be copied, but
we want to return an error code here.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
snprintf() returns the number of characters which would have been
printed if there were enough space. For example, on the first print if
we fill up the 28 character string then it would return a number more
than 30. Use scnprintf() instead because that returns the actual number
of characters printed.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
This patch adds documentation for set_debounce in struct device_node.
Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch adds the missing gpi28 to the list of GPIOs in the GPI P3 "chip".
NOTE: This patch depends on incrementing LPC32XX_GPI_P3_MAX. When applied
without the respective mach-lpc32xx patch (merged via arm-soc.git), gcc will
give a warning about "excess elements in array initializer" but this doesn't
harm.
Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
John W. Linville says:
====================
Here is another batch of updates intended for 3.7...
Highlights include an hci_connect re-write in Bluetooth, HCI/LLC
layer separation in NFC, removal of the raw pn544 NFC driver, NFC LLCP
raw sockets support, improved IBSS auth frame handling in mac80211,
full-MAC AP mode notification support in mac80211, a lot of attention
paid to brcmfmac, and the usual level of updates to iwlwifi, ath9k,
mwifiex, and rt2x00, and various other updates.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Added and modified a few log messages mostly in probe path.
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1) link_status_query() is always called to query the link-speed (speed
after applying qos). When there is no qos setting, link-speed is derived from
port-speed. Do all this inside this routine and hide this from the callers.
2) adpater->phy.forced_port_speed is not being set anywhere after being
initialized. Get rid of this variable.
3) Ignore async link_speed notifications till the initial value has been
fetched from FW.
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All invocations of this routine use the same type value.
Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Simple round-robin hardware TX scheduling can cause starvation of TX rings
with small packets when other TX rings have large TSO or jumbo packets.
In the simplest case, consider 2 TCP streams running in opposite
directions. The TSO TX traffic will hash to one ring and the ACKs for the
incoming data on a different TCP connection will hash to a different TX
ring. The hardware fetches one complete TSO packet (up to 64K data)
before servicing the other TX ring. When it gets to the other TX ring, it
will only fetch one packet (64-byte ACK packet in this case). After that,
it will switch back to the 1st ring filled with more TSO packets. Because
only one ACK can go out roughly every 500 usec in this case, the incoming
data rate becomes very low.
Update version to 3.125.
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Default remains the same.
Reviewed-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
by introducing tg3_stop() that does the opposite of tg3_start(). This
function will be useful when adding the support for changing the numbe
of rx and tx rings.
Reviewed-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
by introducing tg3_start() that handles all initialization steps from
IRQ allocation. This function will be needed when adding support for
changing the number of rx and tx rings.
Reviewed-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
since the number of rings can be different.
Reviewed-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
irq_cnt is no longer necessarily equal to the number rx or tx rings.
Reviewed-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is preparation work to allow the number of RX and TX rings to be
configured separately.
Reviewed-by: Nithin Nayak Sujir <nsujir@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IBM reported a deadlock in select_parent(). This was found to be caused
by taking rename_lock when already locked when restarting the tree
traversal.
There are two cases when the traversal needs to be restarted:
1) concurrent d_move(); this can only happen when not already locked,
since taking rename_lock protects against concurrent d_move().
2) racing with final d_put() on child just at the moment of ascending
to parent; rename_lock doesn't protect against this rare race, so it
can happen when already locked.
Because of case 2, we need to be able to handle restarting the traversal
when rename_lock is already held. This patch fixes all three callers of
try_to_ascend().
IBM reported that the deadlock is gone with this patch.
[ I rewrote the patch to be smaller and just do the "goto again" if the
lock was already held, but credit goes to Miklos for the real work.
- Linus ]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a v7 defconfig enabling highbank, socfpga, mvebu, and vexpress
platforms and their drivers. Most other options are left to the default.
The existing individual platform defconfigs are kept for now as they are
a bit different. In some cases, the choices look pretty arbitrary and
just copied from other defconfigs.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Dinh Nguyen <dinguyen@altera.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
From Ryan Mallon:
* tag 'ep93xx-fixes-for-3.7' of git://github.com/RyanMallon/linux-ep93xx:
ARM: ep93xx: Move ts72xx.h out of include/mach
ARM: ep93xx: use __iomem pointers for MMIO
ARM: ep93xx: Fix build error due to 'SZ_32M' undeclared
From Roland Stigge, three more updates to lpc32xx.
* 'lpc32xx/core' of git://git.antcom.de/linux-2.6:
ARM: LPC32xx: Support GPI 28
ARM: LPC32xx: Platform update for devicetree completion of spi-pl022
ARM: LPC32xx: Board cleanup
From Roland Stigge. Pulling in one bugfix to the lpc32xx DT conversion.
* 'lpc32xx/dts' of git://git.antcom.de/linux-2.6:
ARM: LPC32xx: LED fix in PHY3250 DTS file
mach/include/gpio.h was removed as part of the multiplatform-3.7
update. This patch removes the include from arch-vt8500/vt8500.c
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Olof Johansson <olof@lixom.net>
quite a while ago but have somehow fallen though the cracks
as most of the focus has been making things to work with
device tree. As the first patch depends on sparse IRQ
related removal of irqs.h and related header moves, these
are based on omap-cleanup-local-headers-for-v3.7 tag.
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Merge tag 'omap-devel-board-late-v3-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/cleanup
From Tony Lindgren:
These board and platform related patches have been posted
quite a while ago but have somehow fallen though the cracks
as most of the focus has been making things to work with
device tree. As the first patch depends on sparse IRQ
related removal of irqs.h and related header moves, these
are based on omap-cleanup-local-headers-for-v3.7 tag.
* tag 'omap-devel-board-late-v3-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP2+: serial: Change MAX_HSUART_PORTS to 6
ARM: OMAP4: twl-common: Support for additional devices on i2c1 bus
using device tree.
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Merge tag 'devel-dt-arch-timer-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/dt
From Tony Lindgren:
Few late patches to enable arch timer for omap5
using device tree.
* tag 'devel-dt-arch-timer-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
ARM: OMAP5: Enable arch timer support
ARM: OMAP: Add initialisation for the real-time counter.
framework for omap but unfortunately these patches were not
ready for merging earlier. See also the notes below on the
dependencies these patches have, they are based on a merge
of sereral branches already merged.
From Paul Walmsley <paul@pwsan.com>:
OMAP patches intended for the 3.7 merge window:
- Runtime PM conversions for the GPMC and RNG IP blocks
- Preparation patches for the OMAP common clock framework conversion
- clkdev alias additions required by other drivers
- Performance Monitoring Unit (PMU) support for OMAP2, 3, and non-4430 OMAP4
- OMAP hwmod code and data improvements
- Preparation patches for the IOMMU runtime PM conversion
- Preparation patches for OMAP4 full-chip retention support
Based on a merge of v3.6-rc6, the omap-cleanup-b-for-3.7 tag
(7852ec0536ca39cefffc6301dc77f8ae55592926),the cleanup-fixes-for-v3.7
tag (de6ca33a96), and the
omap-devel-am33xx-for-v3.7 tag
(11964f53eb), due to dependencies.
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Merge tag 'omap-devel-late-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into late/soc
These changes take us a step closer to merging the common clock
framework for omap but unfortunately these patches were not
ready for merging earlier. See also the notes below on the
dependencies these patches have, they are based on a merge
of sereral branches already merged.
From Paul Walmsley <paul@pwsan.com>:
OMAP patches intended for the 3.7 merge window:
- Runtime PM conversions for the GPMC and RNG IP blocks
- Preparation patches for the OMAP common clock framework conversion
- clkdev alias additions required by other drivers
- Performance Monitoring Unit (PMU) support for OMAP2, 3, and non-4430 OMAP4
- OMAP hwmod code and data improvements
- Preparation patches for the IOMMU runtime PM conversion
- Preparation patches for OMAP4 full-chip retention support
Based on a merge of v3.6-rc6, the omap-cleanup-b-for-3.7 tag
(7852ec0536ca39cefffc6301dc77f8ae55592926),the cleanup-fixes-for-v3.7
tag (de6ca33a96), and the
omap-devel-am33xx-for-v3.7 tag
(11964f53eb), due to dependencies.
* tag 'omap-devel-late-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: (281 commits)
ARM: OMAP4460/4470: PMU: Enable PMU for OMAP4460/70
ARM: OMAP2+: PMU: Add runtime PM support
ARM: OMAP4430: PMU: prepare to create PMU device via HWMOD
ARM: OMAP2+: PMU: Convert OMAP2/3 devices to use HWMOD
ARM: OMAP3: hwmod data: Add debugss HWMOD data
ARM: OMAP2+: clockdomain/hwmod: add workaround for EMU clockdomain idle problems
ARM: OMAP: Add a timer attribute for timers that can interrupt the DSP
hwrng: OMAP: remove SoC restrictions from driver registration
ARM: OMAP: split OMAP1, OMAP2+ RNG device registration
hwrng: OMAP: convert to use runtime PM
hwrng: OMAP: store per-device data in per-device variables, not file statics
ARM: OMAP2xxx: hwmod/CM: add RNG integration data
ARM: OMAP2+: gpmc: minimal driver support
ARM: OMAP2+: gpmc: Adapt to HWMOD
ARM: OMAP2/3: hwmod data: add gpmc
ARM: OMAP4: hwmod data: add mmu hwmod for ipu and dsp
ARM: OMAP3: hwmod data: add mmu data for iva and isp
ARM: OMAP: iommu: fix including iommu.h without IOMMU_API selected
ARM: OMAP4: hwmod data: add missing HWMOD_NO_IDLEST flags to some PRCM IP blocks
ARM: OMAP4: hwmod data: make *phy_48m* as the main_clk of ocp2scp
...
After the previous change is_swbp_at_addr() is always called with
current->mm. Remove this check and move it close to its single caller.
Also, remove the obsolete comment about is_swbp_at_addr() and
uprobe_state.count.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Unlike set_swbp(), set_orig_insn()->is_swbp_at_addr() makes sense,
although it can't prevent all confusions.
But the usage of is_swbp_at_addr() is equally confusing, and it adds
the extra get_user_pages() we can avoid.
This patch removes set_orig_insn()->is_swbp_at_addr() but changes
write_opcode() to do the necessary checks before replace_page().
Perhaps it also makes sense to ensure PAGE_MAPPING_ANON in unregister
case.
find_active_uprobe() becomes the only user of is_swbp_at_addr(),
we can change its semantics.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
No functional changes, preparations.
1. Extract the kmap-and-memcpy code from read_opcode() into the
new trivial helper, copy_opcode(). The next patch will add
another user.
2. read_opcode() becomes really trivial, fold it into its single
caller, is_swbp_at_addr().
3. Remove "auprobe" argument from write_opcode(), it is not used
since f403072c6.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
A separate patch for better documentation.
set_swbp()->is_swbp_at_addr() is not needed for correctness, it is
harmless to do the unnecessary __replace_page(old_page, new_page)
when these 2 pages are identical.
And it can not be counted as optimization. mmap/register races are
very unlikely, while in the likely case is_swbp_at_addr() adds the
extra get_user_pages() even if the caller is uprobe_mmap(current->mm)
and returns false.
Note also that the semantics/usage of is_swbp_at_addr() in uprobe.c
is confusing. set_swbp() uses it to detect the case when this insn
was already modified by uprobes, that is why it should always compare
the opcode with UPROBE_SWBP_INSN even if the hardware (like powerpc)
has other trap insns. It doesn't matter if this breakpoint was in fact
installed by gdb or application itself, we are going to "steal" this
breakpoint anyway and execute the original insn from vm_file even if
it no longer matches the memory.
OTOH, handle_swbp()->find_active_uprobe() uses is_swbp_at_addr() to
figure out whether we need to send SIGTRAP or not if we can not find
uprobe, so in this case it should return true for all trap variants,
not only for UPROBE_SWBP_INSN.
This patch removes set_swbp()->is_swbp_at_addr(), the next patches
will remove it from set_orig_insn() which is similar to set_swbp()
in this respect. So the only caller will be handle_swbp() and we
can make its semantics clear.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
valid_vma(false) ignores ->vm_flags, this is not actually right.
We should never try to write into MAP_SHARED mapping, this can
confuse an apllication which actually writes to ->vm_file.
With this patch valid_vma(false) ignores VM_WRITE only but checks
other (immutable) bits checked by valid_vma(true). This can also
speedup uprobe_munmap() and uprobe_unregister().
Note: even after this patch _unregister can confuse the probed
application if it does mprotect(PROT_WRITE) after _register and
installs "int3", but this is hardly possible to avoid and this
doesn't differ from gdb case.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
uprobe_register() or uprobe_mmap() requires VM_READ | VM_EXEC, this
is not right. An apllication can do mprotect(PROT_EXEC) later and
execute this code.
Change valid_vma(is_register => true) to check VM_MAYEXEC instead.
No need to check VM_MAYREAD, it is always set.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
