patch_instruction() can be called very early on ppc32, when the kernel
isn't yet running at it's linked address. That can cause the !
is_kernel_addr() test in __put_user() to trip and call might_sleep()
which is very bad at that point during boot.
Use a lower level function instead for now, at least until we get to
rework ppc32 boot process to do the code patching later, like ppc64
does.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have been observing hangs, both of KVM guest vcpu tasks and more
generally, where a process that is woken doesn't properly wake up and
continue to run, but instead sticks in TASK_WAKING state. This
happens because the update of rq->wake_list in ttwu_queue_remote()
is not ordered with the update of ipi_message in
smp_muxed_ipi_message_pass(), and the reading of rq->wake_list in
scheduler_ipi() is not ordered with the reading of ipi_message in
smp_ipi_demux(). Thus it is possible for the IPI receiver not to see
the updated rq->wake_list and therefore conclude that there is nothing
for it to do.
In order to make sure that anything done before smp_send_reschedule()
is ordered before anything done in the resulting call to scheduler_ipi(),
this adds barriers in smp_muxed_message_pass() and smp_ipi_demux().
The barrier in smp_muxed_message_pass() is a full barrier to ensure that
there is a full ordering between the smp_send_reschedule() caller and
scheduler_ipi(). In smp_ipi_demux(), we use xchg() rather than
xchg_local() because xchg() includes release and acquire barriers.
Using xchg() rather than xchg_local() makes sense given that
ipi_message is not just accessed locally.
This moves the barrier between setting the message and calling the
cause_ipi() function into the individual cause_ipi implementations.
Most of them -- those that used outb, out_8 or similar -- already had
a full barrier because out_8 etc. include a sync before the MMIO
store. This adds an explicit barrier in the two remaining cases.
These changes made no measurable difference to the speed of IPIs as
measured using a simple ping-pong latency test across two CPUs on
different cores of a POWER7 machine.
The analysis of the reason why processes were not waking up properly
is due to Milton Miller.
Cc: stable@vger.kernel.org # v3.0+
Reported-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During a context switch we always restore the per thread DSCR value.
If we aren't doing explicit DSCR management
(ie thread.dscr_inherit == 0) and the default DSCR changed while
the process has been sleeping we end up with the wrong value.
Check thread.dscr_inherit and select the default DSCR or per thread
DSCR as required.
This was found with the following test case, when running with
more threads than CPUs (ie forcing context switching):
http://ozlabs.org/~anton/junkcode/dscr_default_test.c
With the four patches applied I can run a combination of all
test cases successfully at the same time:
http://ozlabs.org/~anton/junkcode/dscr_default_test.chttp://ozlabs.org/~anton/junkcode/dscr_explicit_test.chttp://ozlabs.org/~anton/junkcode/dscr_inherit_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If the default DSCR is non zero we set thread.dscr_inherit in
copy_thread() meaning the new thread and all its children will ignore
future updates to the default DSCR. This is not intended and is
a change in behaviour that a number of our users have hit.
We just need to inherit thread.dscr and thread.dscr_inherit from
the parent which ends up being much simpler.
This was found with the following test case:
http://ozlabs.org/~anton/junkcode/dscr_default_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we update the DSCR either via emulation of mtspr(DSCR) or via
a change to dscr_default in sysfs we don't update thread.dscr.
We will eventually update it at context switch time but there is
a period where thread.dscr is incorrect.
If we fork at this point we will copy the old value of thread.dscr
into the child. To avoid this, always keep thread.dscr in sync with
reality.
This issue was found with the following testcase:
http://ozlabs.org/~anton/junkcode/dscr_inherit_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Writing to dscr_default in sysfs doesn't actually change the DSCR -
we rely on a context switch on each CPU to do the work. There is no
guarantee we will get a context switch in a reasonable amount of time
so fire off an IPI to force an immediate change.
This issue was found with the following test case:
http://ozlabs.org/~anton/junkcode/dscr_explicit_test.c
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> # 3.0+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The CPU hotplug code for the powernv platform currently only puts
offline CPUs into nap mode if the powersave_nap variable is set.
However, HV-style KVM on this platform requires secondary CPU threads
to be offline and in nap mode. Since we know nap mode works just
fine on all POWER7 machines, and the only machines that support the
powernv platform are POWER7 machines, this changes the code to
always put offline CPUs into nap mode, regardless of powersave_nap.
Powersave_nap still controls whether or not CPUs go into nap mode
when idle, as before.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At the moment the handler for hypervisor decrementer interrupts is
the same as for decrementer interrupts, i.e. timer_interrupt().
This is bogus; if we ever do get a hypervisor decrementer interrupt
it won't have anything to do with the next timer event. In fact
the only time we get hypervisor decrementer interrupts is when one
is left pending on exit from a KVM guest.
When we get a hypervisor decrementer interrupt we don't need to do
anything special to clear it, since they are edge-triggered on the
transition of HDEC from 0 to -1. Thus this adds an empty handler
function for them. We don't need to have them masked when interrupts
are soft-disabled, so we use STD_EXCEPTION_HV instead of
MASKABLE_EXCEPTION_HV.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch_update_cpu_topology() should only return 1 when the topology has
actually changed, and should return 0 otherwise.
This patch fixes a potential bug where rebuild_sched_domains() would
reinitialize the sched domains even when the topology hasn't changed.
Signed-off-by: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This reverts commit b1acf1bb54.
Something went horribly wrong when I did savedefconfig, not sure what,
but what's in there is busted so let's revert it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
For certain speculative events on Power7, 'perf stat' reports far higher
event count than 'perf record' for the same event.
As described in following commit, a performance monitor exception is raised
even when the the performance events are rolled back.
commit 0837e3242c
Author: Anton Blanchard <anton@samba.org>
Date: Wed Mar 9 14:38:42 2011 +1100
perf_event_interrupt() records an event only when an overflow occurs. But
this check for overflow is a simple 'if (val < 0)'.
Because the events are rolled back, this check for overflow fails and the
event is not recorded. perf_event_interrupt() later uses pmc_overflow() to
detect the overflow and resets the counters and the events are lost completely.
To properly detect the overflow of rolled back events, use pmc_overflow()
even when recording events.
To reproduce:
$ cat strcpy.c
#include <stdio.h>
#include <string.h>
main()
{
char buf[256];
alarm(5);
while(1)
strcpy(buf, "string1");
}
$ perf record -e r20014 ./strcpy
$ perf report -n > report.1
$ perf stat -e r20014 > report.2
# Compare report.1 and report.2
Reported-by: Maynard Johnson <mpjohn@us.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The enhanced prefetch hint patches corrupt the condition register
that was used to check if we are in interrupt. Fix this by using cr1.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
"powerpc: Use enhanced touch instructions in POWER7
copy_to_user/copy_from_user" was applied twice. Remove one.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Directly comparing current->personality against PER_LINUX32 doesn't work
in cases when any of the personality flags stored in the top three bytes
are used.
Directly forcefully setting personality to PER_LINUX32 or PER_LINUX
discards any flags stored in the top three bytes
Use personality() macro to compare only PER_MASK bytes and make sure that
we are setting only the bits that should be set, instead of overwriting
the whole value.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Checking for device mask to cover the whole IOMMU table is too strict.
IOMMU allocators should handle mask constraint properly for each
allocation.
The patch enables to use old AirPort Extreme cards on PowerMacs with
more than 1GB of memory; without the patch the driver init fails with:
b43-pci-bridge 0001:01:01.0: Warning: IOMMU window too big for device mask
b43-pci-bridge 0001:01:01.0: mask: 0x3fffffff, table end: 0x80000000
b43-phy0 ERROR: The machine/kernel does not support the required 30-bit DMA mask
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
For powerpc BooKE and e200, singlestep is handled on the critical/dbg
exception stack. This causes current_thread_info() to fail for kgdb
internal, so previously We work around this issue by copying
the thread_info from the kernel stack before calling kgdb_handle_exception,
and copying it back afterwards.
But actually we don't do this properly. We should backup current_thread_info
then restore that when exit.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We need to skip a breakpoint exception when it occurs after
a breakpoint has already been removed.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The kgdb_single_step flag has the possibility to indefinitely
hang the system on an SMP system.
The x86 arch have the same problem, and that problem was fixed by
commit 8097551d9ab9b9e3630(kgdb,x86: do not set kgdb_single_step
on x86). This patch does the same behaviors as x86's patch.
Signed-off-by: Dongdong Deng <dongdong.deng@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add several #includes that mpic_msgr relies on being pulled implicitly,
which only happens on certain configs.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Meador Inge <meador_inge@mentor.com>
Cc: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently if you are doing a global perf recording with hardware
breakpoints (ie perf record -e mem:0xdeadbeef -a), you can oops with:
Faulting instruction address: 0xc000000000738890
cpu 0xc: Vector: 300 (Data Access) at [c0000003f76af8d0]
pc: c000000000738890: .hw_breakpoint_handler+0xa0/0x1e0
lr: c000000000738830: .hw_breakpoint_handler+0x40/0x1e0
sp: c0000003f76afb50
msr: 8000000000001032
dar: 6f0
dsisr: 42000000
current = 0xc0000003f765ac00
paca = 0xc00000000f262a00 softe: 0 irq_happened: 0x01
pid = 6810, comm = loop-read
enter ? for help
[c0000003f76afbe0] c00000000073cd04 .notifier_call_chain.isra.0+0x84/0xe0
[c0000003f76afc80] c00000000073cdbc .notify_die+0x3c/0x60
[c0000003f76afd20] c0000000000139f0 .do_dabr+0x40/0xf0
[c0000003f76afe30] c000000000005a9c handle_dabr_fault+0x14/0x48
--- Exception: 300 (Data Access) at 0000000010000480
SP (ff8679e0) is in userspace
This is because we don't check to see if the break point is associated
with task before we deference the task_struct pointer.
This changes the update to use current.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There are a few whitespace goolies in xmon.c, some of them appear to
be my fault. Fix them all in one go.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since the printk internals were reworked the xmon 'dl' command which
dumps the content of __log_buf has stopped working.
It is now a structured buffer, so just dumping it doesn't really work.
Use the helpers added for kgdb to print out the content.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Yocto (Built by Poky 7.0) 1.2 root filesystems fail to boot,
at least over nfs, with:
Failed to mount /dev: No such device
Configuring DEVTMPFS fixes it.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
run make savedefconfig on fsl defconfigs.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Put the parameters the right way around
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=44031
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
When we map a page that wasn't icache cleared before, do so when first
mapping it in KVM using the same information bits as the Linux mapping
logic. That way we are 100% sure that any page we map does not have stale
entries in the icache.
Signed-off-by: Alexander Graf <agraf@suse.de>
In handling the H_CEDE hypercall, if this vcpu has already been
prodded (with the H_PROD hypercall, which Linux guests don't in fact
use), we branch to a numeric label '1f'. Unfortunately there is
another '1:' label before the one that we want to jump to. This fixes
the problem by using a textual label, 'kvm_cede_prodded'. It also
changes the label for another longish branch from '2:' to
'kvm_cede_exit' to avoid a possible future problem if code modifications
add another numeric '2:' label in between.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Add the missing usb controller version info and port0, which is
required during setup usb phy.
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
We change fsl_add_bridge to return -ENODEV if the controller is working in
agent mode. Then check the return value of fsl_add_bridge to guarantee
that only successfully added host bus will be scanned.
Signed-off-by: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Commit b38c77d82e moved the MTMSR_EERI macro from the KVM code to generic
ppc_asm.h code. However, while adding it in the headers for the ppc32 case,
it missed out to remove the former definition in the KVM code.
This patch fixes compilation on server type PPC32 targets with CONFIG_KVM
enabled.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rather than #define the options manually in the architecture code, add
Kconfig options for them and select them there instead. This also allows
us to select the compat IPC version parsing automatically for platforms
using the old compat IPC interface.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE and use this instead
of the multitude of #if defined() checks in atomic64_test.c
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 9adc5374 ('common: dma-mapping: introduce mmap method') added a
generic method for implementing mmap user call to dma_map_ops structure.
This patch converts ARM and PowerPC architectures (the only providers of
dma_mmap_coherent/dma_mmap_writecombine calls) to use this generic
dma_map_ops based call and adds a generic cross architecture
definition for dma_mmap_attrs, dma_mmap_coherent, dma_mmap_writecombine
functions.
The generic mmap virt_to_page-based fallback implementation is provided for
architectures which don't provide their own implementation for mmap method.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
As Colin Cross ported my x86 change to ARM, he also pointed out that
powerpc is also behind in this fix.
The commit 722b3c7469 "ftrace/graph: Trace function entry before
updating index" fixes an issue with function graph tracing for x86,
where if the called entry function decides not to trace interrupts, it
can fail the check if an interrupt comes in just after the
curr_ret_stack is updated.
The solution is to call the entry function first, then update the
curr_ret_stack if the entry function wants to be traced.
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reduce the severity of the warning given when firmware flash is
not supported. Not all platforms have it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Enable the hardware RNG and crypto modules. I verified they both
autoload via the VIO subsystem, so there is no need to build them in.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This updates the g5 defconfig to include nouveau instead of nvidiafb
(which works much better nowadays, in fact the latter crashes on modern
distros), and to set CONFIG_VT_HW_CONSOLE_BINDING without which takeover
from the firmware offb by nouveau doesn't work properly (and leads to
unexplained black screens for some users).
The rest is churn of going through defconfig / savedefconfig
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
After merging the register type check patches from Ben's tree, the
hv enabled booke implementation ceased to compile.
This patch fixes things up so everyone's happy again.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 9778b696a0 incorrectly
changes the code setting the stack limit on entry to the
kernel to mark the thread_info at the bottom of the stack
out of bounds anymore. This fixes it.
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In order for indirect mode on the PIXIS to work properly, both chip selects
need to be set to GPCM mode, otherwise writes to the chip select base
addresses will not actually post to the local bus -- they'll go to the
NAND controller instead. Therefore, we need to set BR0 and BR1 to GPCM
mode before switching to indirect mode.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The Freescale P1022 has a unique pin muxing "feature" where the DIU video
controller's video signals are muxed with 24 of the local bus address signals.
When the DIU is enabled, the bulk of the local bus is disabled, preventing
access to memory-mapped devices like NAND flash and the pixis FPGA.
Therefore, if the DIU is going to be enabled, then memory-mapped devices on
the localbus, like NAND flash, need to be disabled.
This patch is similar to "powerpc/85xx: p1022ds: disable the NOR flash node
if video is enabled", except that it disables the NAND flash node instead.
This PIXIS node needs to remain enabled because it is used by platform code
to switch into indirect mode.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
The sram_offset parameter represents a physical address and should be of
type phys_addr_t. As part of this fix, the extraction of sram_params is
being cleaned-up and fixed.
This patch fixes now the case when the offset value of 0xfff00000 was being
rejected by the driver (returning -EINVAL), although this is a valid offset
value.
Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Benjamin Herrenschmidt