When we take an exception at EL1, we only want to enable debug
exceptions if we're not currently stepping, otherwise we can easily get
stuck in a loop stepping into interrupt handlers.
Unfortunately, the current code tests the wrong bit in the mdscr, so fix
that.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
It is required to enable respective clock-domain before
enabling any clock/module inside that clock-domain.
During common-clock migration, .clkdm_name field got missed
for "clkdiv32k_ick" clock, which leaves "clk_24mhz_clkdm"
unused; so it will be disabled even if childs of this clock-domain
is enabled, which keeps child modules in idle mode.
This fixes the kernel crash observed on AM335xEVM-SK platform,
where clkdiv32_ick clock is being used as a gpio debounce clock
and since clkdiv32k_ick is in idle mode it leads to below crash -
Crash Log:
==========
[ 2.598347] Unhandled fault: external abort on non-linefetch (0x1028) at
0xfa1ac150
[ 2.606434] Internal error: : 1028 [#1] SMP ARM
[ 2.611207] Modules linked in:
[ 2.614449] CPU: 0 Not tainted (3.8.4-01382-g1f449cd-dirty #4)
[ 2.620973] PC is at _set_gpio_debounce+0x60/0x104
[ 2.626025] LR is at clk_enable+0x30/0x3c
Cc: stable@vger.kernel.org # v3.9
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Cc: Rajendra Nayak <rnayak@ti.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
With the latest device tree reorganization which introduced the
'internal-reg' node, now the only region translated is the internal register's.
This makes the description of the hardware incomplete, for it lacks the
Device Bus childs address space.
In order to fix this, it's required to add a 'ranges' entry with a suitable
address space to map Device Bus childs, on a per-board basis.
This patch fixes the ranges property on the Armada XP GP board.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
The cpu-info array starts with a list of cpus in configured state,
followed by the cpus in standby state. The comparison to decide which
state a cpu has is incorrect, this causes configured cpus appear as
standby cpus. The correct comparison is the index of the new cpu in
the cpu-info array vs. the number of configured cpus.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This reverts commit d532f3d26716a39dfd4b88d687bd344fbe77e390.
The original commit has several problems:
1) Doesn't work with 64-bit kernels.
2) Calls TLBMISS_HANDLER_SETUP() before the code is generated.
3) Calls TLBMISS_HANDLER_SETUP() twice in per_cpu_trap_init() when
only one call is needed.
[ralf@linux-mips.org: Also revert the bits of the ASID patch which were
hidden in the KVM merge.]
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5242/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This reverts commit f6b06d9361a008afb93b97fb3683a6e92d69d0f4.
The next revert depends on this one, so this has to go too.
Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: "Steven J. Hill" <Steven.Hill@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/5241/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
omap2plus_defconfig is missing CONFIG_ARCH_MULTI_V6. This results in
undefined instruction traps in u-boot (and boot failures) on OMAP2xxx
SoCs, which are ARM11-based. Fix by setting CONFIG_ARCH_MULTI_V6.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Fix to return -ENOMEM in the d->chan alloc error handling
case instead of 0, as done elsewhere in this function.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Commit ad871c10 (ARM: dts: OMAP: Add usb_otg and glue data to
OMAP3+ boards) added support for MUSB on omap3 for device tree,
but added the interrupts the wrong way probably as they were
copied from the omap4.dtsi file. On omap3 we have TI specific
interrupt controller, not GIC.
Fix this by specifying the interrupt following the TI INTC
binding.
Without this fix MUSB won't work as it is trying to use
irq0 instead of irq92.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Pull x86 fixes from Thomas Gleixner:
- Fix for a CPU hot-add deadlock in microcode update code
- Fix for idle consolidation fallout
- Documentation update for initial kernel direct mapping
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Add missing comments for initial kernel direct mapping
x86/microcode: Add local mutex to fix physical CPU hot-add deadlock
x86: Fix idle consolidation fallout
Pull timer fixes from Thomas Gleixner:
- Cure for not using zalloc in the first place, which leads to random
crashes with CPUMASK_OFF_STACK.
- Revert a user space visible change which broke udev
- Add a missing cpu_online early return introduced by the new full
dyntick conversions
- Plug a long standing race in the timer wheel cpu hotplug code.
Sigh...
- Cleanup NOHZ per cpu data on cpu down to prevent stale data on cpu
up.
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons
timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE
tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offline
tick: Cleanup NOHZ per cpu data on cpu down
tick: Use zalloc_cpumask_var for allocating offstack cpumasks
Pull core fixes from Thomas Gleixner:
- Two fixlets for the fallout of the generic idle task conversion
- Documentation update
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcu/idle: Wrap cpu-idle poll mode within rcu_idle_enter/exit
idle: Fix hlt/nohlt command-line handling in new generic idle
kthread: Document ways of reducing OS jitter due to per-CPU kthreads
Pull ARM fixes from Russell King:
"A small number of fixes for stuff from the last merge window, and in
one case (IRQ time accounting) the previous merge window."
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7720/1: ARM v6/v7 cmpxchg64 shouldn't clear upper 32 bits of the old/new value
ARM: 7715/1: MCPM: adapt to GIC changes after upstream merge
ARM: 7714/1: mmc: mmci: Ensure return value of regulator_enable() is checked
ARM: 7712/1: Remove trailing whitespace in arch/arm/Makefile
ARM: 7711/1: dove: fix Dove cpu type from V7 to PJ4
ARM: finally enable IRQ time accounting config
Commit 84ebc10294a3d7be4c66f51070b7aedbaa24de9b (USB: remove
CONFIG_USB_SUSPEND option) failed to remove all of the usages of
USB_SUSPEND throughout the kernel. This patch (as1677) removes the
remaining instances of that symbol.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MACH_MOP500 selects REGULATOR_FIXED_VOLTAGE but not REGULATOR. This
patch makes it select the latter too.
Seen as:
warning: (MACH_DOVE_DT && ARCH_KIRKWOOD_DT && MACH_AMS_DELTA &&
MACH_MOP500 && TPS6105X) selects REGULATOR_FIXED_VOLTAGE which has
unmet direct dependencies (REGULATOR)
Signed-off-by: Emilio López <emilio@elopez.com.ar>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tony Jones reported that the ftrace self tests on s390 do not work:
<6>Testing dynamic ftrace ops #1: (0 0 0 0 0) FAILED!
<6>Testing tracer irqsoff:
<3>failed to start irqsoff tracer
<4>.. no entries found ..FAILED!
<6>Testing tracer wakeup:
<3>failed to start wakeup tracer
<4>.. no entries found ..FAILED!
<6>Testing tracer function_graph:
<4>Failed to init function_graph tracer, init returned -19
<4>FAILED!
This happens because we forgot to adjust the instruction pointer that gets
passed to the ftrace trace function by MCOUNT_INSN_SIZE.
In addition change MCOUNT_INSN_SIZE to the correct value on 31 bit.
It only worked so far because the to be patched instruction was identical.
Reported-by: Tony Jones <tonyj@suse.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
On heavy paging load some guest cpus started to loop in gmap_ipte_notify.
This was visible as stalled cpus inside the guest. The gmap_ipte_notifier
tries to map a user page and then made sure that the pte is valid and
writable. Turns out that with the software change bit tracking the pte
can become read-only (and only software writable) if the page is clean.
Since we loop in this code, the page would stay clean and, therefore,
be never writable again.
Let us just use fixup_user_fault, that guarantees to call handle_mm_fault.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
since commit 838a2ae80a6ab52139fb1bf0a93ea8c5eff94488
Author: Shawn Guo <shawn.guo@linaro.org>
Date: Sat Jan 12 11:50:05 2013 +0000
ARM: use clockevents_config_and_register() where possible
The timer is wrongly configured and result in a nice crash
so revert it on rm9200 timer.
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: stable <stable@vger.kernel.org> # 3.8+
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
CONFIG_ARCH_SUNXI currently doesn't enable a gpiolib, which causes build
problems when building a kernel with only the sunxi platform enabled.
Select ARCH_REQUIRE_GPIOLIB to solve this.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Emilio López <emilio@elopez.com.ar>
The TB10x platform port includes a custom mechanism using to set up
default pin controller configurations using abilis,simple-default
pin configurations of nodes compatible with abilis,simple-pinctrl. This
mechanism is redundant with the Linux standard "default" pin
configuration, see commit ab78029ecc347debbd737f06688d788bd9d60c1d
"drivers/pinctrl: grab default handles from device core".
This patch removes the TB10x custom mechanism in favour of the Linux
standard.
Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Kay Sievers noted that the ALWAYS_USE_PERSISTENT_CLOCK config,
which enables some minor compile time optimization to avoid
uncessary code in mostly the suspend/resume path could cause
problems for userland.
In particular, the dependency for RTC_HCTOSYS on
!ALWAYS_USE_PERSISTENT_CLOCK, which avoids setting the time
twice and simplifies suspend/resume, has the side effect
of causing the /sys/class/rtc/rtcN/hctosys flag to always be
zero, and this flag is commonly used by udev to setup the
/dev/rtc symlink to /dev/rtcN, which can cause pain for
older applications.
While the udev rules could use some work to be less fragile,
breaking userland should strongly be avoided. Additionally
the compile time optimizations are fairly minor, and the code
being optimized is likely to be reworked in the future, so
lets revert this change.
Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: stable <stable@vger.kernel.org> #3.9
Cc: Feng Tang <feng.tang@intel.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Link: http://lkml.kernel.org/r/1366828376-18124-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As per commit 764e0da1 (timers: Fixup the Kconfig consolidation
fallout), init/Kconfig already includes kernel/time/Kconfig, so no need
to do it explicitly for arm64.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The format of the lower 32-bits of the 64-bit operand to 'dc cisw' is
unchanged from ARMv7 architecture and the upper bits are RES0. This
implies that the 'way' field of the operand of 'dc cisw' occupies the
bit-positions [31 .. (32-A)]. Due to the use of 64-bit extended operands
to 'clz', the existing implementation of __flush_dcache_all is incorrectly
placing the 'way' field in the bit-positions [63 .. (64-A)].
Signed-off-by: Sukanto Ghosh <sghosh@apm.com>
Tested-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@vger.kernel.org
The of_platform_populate() is currently invoked at device_initcall()
level. There are however drivers that use platform_driver_probe()
directly and they need the devices to be populated. This patch makes the
of_platform_populate() and arch_initcall().
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Benoit Lecardonnel <Benoit.Lecardonnel@synopsys.com>
Tested-by: Benoit Lecardonnel <Benoit.Lecardonnel@synopsys.com>
Pull powerpc fixes from Benjamin Herrenschmidt:
"This is mostly bug fixes (some of them regressions, some of them I
deemed worth merging now) along with some patches from Li Zhong
hooking up the new context tracking stuff (for the new full NO_HZ)"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
powerpc: Set show_unhandled_signals to 1 by default
powerpc/perf: Fix setting of "to" addresses for BHRB
powerpc/pmu: Fix order of interpreting BHRB target entries
powerpc/perf: Move BHRB code into CONFIG_PPC64 region
powerpc: select HAVE_CONTEXT_TRACKING for pSeries
powerpc: Use the new schedule_user API on userspace preemption
powerpc: Exit user context on notify resume
powerpc: Exception hooks for context tracking subsystem
powerpc: Syscall hooks for context tracking subsystem
powerpc/booke64: Fix kernel hangs at kernel_dbg_exc
powerpc: Fix irq_set_affinity() return values
powerpc: Provide __bswapdi2
powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3
powerpc/powernv: Detect OPAL v3 API version
powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning again
powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FS
powerpc: Bring all threads online prior to migration/hibernation
powerpc/rtas_flash: Fix validate_flash buffer overflow issue
powerpc/kexec: Fix kexec when using VMX optimised memcpy
powerpc: Fix build errors STRICT_MM_TYPECHECKS
...
Instead of requesting all available spi cs-gpios, request only the ones used on
the board, in our case on the cpu module.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
First Ethernet device has a ".0" appended onto the device name.
Since on a non-DT boot the ethernet will be named "smsc911x.0"
and since the clocks are not converted to device tree these
names need to be matched when providing the name from
auxdata.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[edited commit message]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
A recent move to rid header files which were hindering multiplatform
support forced address allocations out of the headers and into the
files which were using them. We also lost some useful macros such as
IO_ADDRESS(), so physical -> virtual addressing has been carried out
manually in this case. Unfortunately the incorrect value was converted.
This patch rectifies the error and ensures earlyprintk works again.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Since: "05ec260 mfd: db8500-prcmu: update resource passing", the AB8500's
platform data 'ab8500_platdata' is passed directly as an attribute to
'db8500_prcmu_pdata', so there's no requirement to assign it a second
time. In fact, it's only due to an ordering issue that the entire
'db8500_prcmu_pdata' data structure isn't completely over-written by the
assignment in u8500_init_devices().
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
That will be better initial the value of DataSize to zero for the input of
GetVariable(), otherwise we will feed a random value. The debug log of input
DataSize like this:
...
[ 195.915612] EFI Variables Facility v0.08 2004-May-17
[ 195.915819] efi: size: 18446744071581821342
[ 195.915969] efi: size': 18446744071581821342
[ 195.916324] efi: size: 18446612150714306560
[ 195.916632] efi: size': 18446612150714306560
[ 195.917159] efi: size: 18446612150714306560
[ 195.917453] efi: size': 18446612150714306560
...
The size' is value that was returned by BIOS.
After applied this patch:
[ 82.442042] EFI Variables Facility v0.08 2004-May-17
[ 82.442202] efi: size: 0
[ 82.442360] efi: size': 1039
[ 82.443828] efi: size: 0
[ 82.444127] efi: size': 2616
[ 82.447057] efi: size: 0
[ 82.447356] efi: size': 5832
...
Found on Acer Aspire V3 BIOS, it will not return the size of data if we input a
non-zero DataSize.
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Compilation warning:
arch/microblaze/kernel/cpu/cache.c:148:2: warning:
'temp' is used uninitialized in this function [-Wuninitialized]
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Currently we only set the "to" address in the branch stack when the CPU
explicitly gives us a value. Unfortunately it only does this for XL form
branches (eg blr, bctr, bctar) and not I and B form branches (eg b, bc).
Fortunately if we read the instruction from memory we can extract the offset of
a branch and calculate the target address.
This adds a function power_pmu_bhrb_to() to calculate the target/to address of
the corresponding I and B form branches. It handles branches in both user and
kernel spaces. It also plumbs this into the perf brhb reading code.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current Branch History Rolling Buffer (BHRB) code misinterprets the order
of entries in the hardware buffer. It assumes that a branch target address
will be read _after_ its corresponding branch. In reality the branch target
comes before (lower mfbhrb entry) it's corresponding branch.
This is a rewrite of the code to take this into account.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The new Branch History Rolling buffer (BHRB) code is only useful on 64bit
processors, so move it into the #ifdef CONFIG_PPC64 region.
This avoids code bloat on 32bit systems.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Start context tracking support from pSeries.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch corresponds to
[PATCH] x86: Use the new schedule_user API on userspace preemption
commit 0430499ce9d78691f3985962021b16bf8f8a8048
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch allows RCU usage in do_notify_resume, e.g. signal handling.
It corresponds to
[PATCH] x86: Exit RCU extended QS on notify resume
commit edf55fda35c7dc7f2d9241c3abaddaf759b457c6
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is the exception hooks for context tracking subsystem, including
data access, program check, single step, instruction breakpoint, machine check,
alignment, fp unavailable, altivec assist, unknown exception, whose handlers
might use RCU.
This patch corresponds to
[PATCH] x86: Exception hooks for userspace RCU extended QS
commit 6ba3c97a38803883c2eee489505796cb0a727122
But after the exception handling moved to generic code, and some changes in
following two commits:
56dd9470d7c8734f055da2a6bac553caf4a468eb
context_tracking: Move exception handling to generic code
6c1e0256fad84a843d915414e4b5973b7443d48d
context_tracking: Restore correct previous context state on exception exit
it is able for exception hooks to use the generic code above instead of a
redundant arch implementation.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is the syscall slow path hooks for context tracking subsystem,
corresponding to
[PATCH] x86: Syscall hooks for userspace RCU extended QS
commit bf5a3c13b939813d28ce26c01425054c740d6731
TIF_MEMDIE is moved to the second 16-bits (with value 17), as it seems there
is no asm code using it. TIF_NOHZ is added to _TIF_SYCALL_T_OR_A, so it is
better for it to be in the same 16 bits with others in the group, so in the
asm code, andi. with this group could work.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
MSR_DE is not cleared on entry to the kernel, and we don't clear it
explicitly outside of debug code. If we have MSR_DE set in
prime_debug_regs(), and the new thread has events enabled in DBCR0
(e.g. ICMP is set in thread->dbsr0, even though it was cleared in the
real DBCR0 when the thread got scheduled out), we'll end up taking a
debug exception in the kernel when DBCR0 is loaded. DSRR0 will not
point to an exception vector, and the kernel ends up hanging at
kernel_dbg_exc. Fix this by always clearing MSR_DE when we load new
debug state.
Another observed source of kernel_dbg_exc hangs is with the branch
taken event. If this event is active, but we take a non-debug trap
(e.g. a TLB miss or an asynchronous interrupt) before the next branch.
We end up taking a branch-taken debug exception on the initial branch
instruction of the exception vector, but because the debug exception is
DBSR_BT rather than DBSR_IC we branch to kernel_dbg_exc before even
checking the DSRR0 address. Fix this by checking for DBSR_BT as well
as DBSR_IC, which is what 32-bit does and what the comments suggest was
intended in the 64-bit code as well.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some versions of GCC apparently expect this to be provided by libgcc.
Updates from Mikey to fix 32 bit version and adding "r" to registers.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current code fails to handle kexec on OPALv2. This fixes it
and adds code to improve the situation on OPALv3 where we can
query the CPU status from the firmware and decide what to do
based on that.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Saw this warning again, and this time from the ret_from_fork path.
It seems we could clear the back chain earlier in copy_thread(), which
could cover both path, and also fix potential lockdep usage in
schedule_tail(), or exception occurred before we clear the back chain.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>