In f761622e59 we changed
early_setup_secondary so it's called using the proper kernel stack
rather than the emergency one.
Unfortunately, this stack pointer can't be used when translation is off
on PHYP as this stack pointer might be outside the RMO. This results in
the following on all non zero cpus:
cpu 0x1: Vector: 300 (Data Access) at [c00000001639fd10]
pc: 000000000001c50c
lr: 000000000000821c
sp: c00000001639ff90
msr: 8000000000001000
dar: c00000001639ffa0
dsisr: 42000000
current = 0xc000000016393540
paca = 0xc000000006e00200
pid = 0, comm = swapper
The original patch was only tested on bare metal system, so it never
caught this problem.
This changes __secondary_start so that we calculate the new stack
pointer but only start using it after we've called early_setup_secondary.
With this patch, the above problem goes away.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 0fe1ac48 ("powerpc/perf_event: Fix oops due to
perf_event_do_pending call") moved the call to perf_event_do_pending
in timer_interrupt() down so that it was after the irq_enter() call.
Unfortunately this moved it after the code that checks whether it
is time for the next decrementer clock event. The result is that
the call to perf_event_do_pending() won't happen until the next
decrementer clock event is due. This was pointed out by Milton
Miller.
This fixes it by moving the check for whether it's time for the
next decrementer clock event down to the point where we're about
to call the event handler, after we've called perf_event_do_pending.
This has the side effect that on old pre-Core99 Powermacs where we
use the ppc_n_lost_interrupts mechanism to replay interrupts, a
replayed interrupt will incur a little more latency since it will
now do the code from the irq_enter down to the irq_exit, that it
used to skip. However, these machines are now old and rare enough
that this doesn't matter. To make it clear that ppc_n_lost_interrupts
is only used on Powermacs, and to speed up the code slightly on
non-Powermac ppc32 machines, the code that tests ppc_n_lost_interrupts
is now conditional on CONFIG_PMAC as well as CONFIG_PPC32.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Call kexec purgatory code correctly. We were getting lucky before.
If you examine the powerpc 32bit kexec "purgatory" code you will
see it expects the following:
>From kexec-tools: purgatory/arch/ppc/v2wrap_32.S
-> calling convention:
-> r3 = physical number of this cpu (all cpus)
-> r4 = address of this chunk (master only)
As such, we need to set r3 to the current core, r4 happens to be
unused by purgatory at the moment but we go ahead and set it
here as well
Signed-off-by: Matthew McClintock <msm@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pci_device_to_OF_node() can return null, and list_for_each_entry will
never enter the loop when dev is NULL, so it looks like this test is
a typo.
Reported-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As early setup calls down to slb_initialize(), we must have kstack
initialised before checking "should we add a bolted SLB entry for our kstack?"
Failing to do so means stack access requires an SLB miss exception to refill
an entry dynamically, if the stack isn't accessible via SLB(0) (kernel text
& static data). It's not always allowable to take such a miss, and
intermittent crashes will result.
Primary CPUs don't have this issue; an SLB entry is not bolted for their
stack anyway (as that lives within SLB(0)). This patch therefore only
affects the init of secondaries.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When looking at some issues with the virtual ethernet driver I noticed
that TCE allocation was following a very strange pattern:
address 00e9000 length 2048
address 0409000 length 2048 <-----
address 0429000 length 2048
address 0449000 length 2048
address 0469000 length 2048
address 0489000 length 2048
address 04a9000 length 2048
address 04c9000 length 2048
address 04e9000 length 2048
address 4009000 length 2048 <-----
address 4029000 length 2048
Huge unexplained gaps in what should be an empty TCE table. It turns out
it_blocksize, the amount we want to align the next allocation to, was
c0000000fe903b20. Completely bogus.
Initialise it to something reasonable in the VIO IOMMU code, and use kzalloc
everywhere to protect against this when we next add a non compulsary
field to iommu code and forget to initialise it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
I'm sick of seeing ppc64_runlatch_off in our profiles, so inline it
into the callers. To avoid a mess of circular includes I didn't add
it as an inline function.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The 'smt_enabled=X' boot option does not handle values of X > 2.
For Power 7 processors with smt modes of 0,1,2,3, and 4 this does
not work. This patch allows the smt_enabled option to be set to
any value limited to a max equal to the number of threads per
core.
Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During CPU offline/online tests __cpu_up would flood the logs with
the following message:
Processor 0 found.
This provides no useful information to the user as there is no context
provided, and since the operation was a success (to this point) it is expected
that the CPU will come back online, providing all the feedback necessary.
Change the "Processor found" message to DBG() similar to other such messages in
the same function. Also, add an appropriate log level for the "Processor is
stuck" message.
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Acked-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Nathan Fontenot <nfont@austin.ibm.com>
Cc: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
start_secondary() is called shortly after _start and also via
cpu_idle()->cpu_die()->pseries_mach_cpu_die()
start_secondary() expects a preempt_count() of 0. pseries_mach_cpu_die() is
called via the cpu_idle() routine with preemption disabled, resulting in the
following repeating message during rapid cpu offline/online tests
with CONFIG_PREEMPT=y:
BUG: scheduling while atomic: swapper/0/0x00000002
Modules linked in: autofs4 binfmt_misc dm_mirror dm_region_hash dm_log [last unloaded: scsi_wait_scan]
Call Trace:
[c00000010e7079c0] [c0000000000133ec] .show_stack+0xd8/0x218 (unreliable)
[c00000010e707aa0] [c0000000006a47f0] .dump_stack+0x28/0x3c
[c00000010e707b20] [c00000000006e7a4] .__schedule_bug+0x7c/0x9c
[c00000010e707bb0] [c000000000699d9c] .schedule+0x104/0x800
[c00000010e707cd0] [c000000000015b24] .cpu_idle+0x1c4/0x1d8
[c00000010e707d70] [c0000000006aa1b4] .start_secondary+0x398/0x3d4
[c00000010e707e30] [c000000000008278] .start_secondary_resume+0x10/0x14
Move the cpu_die() call inside the existing preemption enabled block of
cpu_idle(). This is safe as the idle task is affined to a single CPU so the
debug_smp_processor_id() tests (from cpu_should_die()) won't trigger as we are
in a "migration disabled" region.
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Acked-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Nathan Fontenot <nfont@austin.ibm.com>
Cc: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
list_for_each_entry binds its first argument to a non-null value, and thus
any null test on the value of that argument is superfluous.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
iterator I;
expression x,E,E1,E2;
statement S,S1,S2;
@@
I(x,...) { <...
- if (x != NULL || ...)
S
...> }
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During kdump we run the crash handlers first then stop all other CPUs.
We really want to stop all CPUs as close to the fail as possible and also
have a very controlled environment for running the crash handlers, so it
makes sense to reverse the order.
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The interrupt stacks need to be indexed by the physical cpu since the
critical, debug and machine check handlers use the contents of SPRN_PIR to
index the critirq_ctx, dbgirq_ctx, and mcheckirq_ctx arrays.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
There are two entries for .cpu_user_features in
arch/powerpc/kernel/cputable.c. Remove the one that doesn't belong
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Clear the machine check syndrom register before enabling machine check
interrupts. The initial state of the tlb can lead to parity errors being
flagged early after a cold boot.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Make do_execve() take a const filename pointer so that kernel_execve() compiles
correctly on ARM:
arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type
This also requires the argv and envp arguments to be consted twice, once for
the pointer array and once for the strings the array points to. This is
because do_execve() passes a pointer to the filename (now const) to
copy_strings_kernel(). A simpler alternative would be to cast the filename
pointer in do_execve() when it's passed to copy_strings_kernel().
do_execve() may not change any of the strings it is passed as part of the argv
or envp lists as they are some of them in .rodata, so marking these strings as
const should be fine.
Further kernel_execve() and sys_execve() need to be changed to match.
This has been test built on x86_64, frv, arm and mips.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark arguments to certain system calls as being const where they should be but
aren't. The list includes:
(*) The filename arguments of various stat syscalls, execve(), various utimes
syscalls and some mount syscalls.
(*) The filename arguments of some syscall helpers relating to the above.
(*) The buffer argument of various write syscalls.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'timers-timekeeping-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
um: Fix read_persistent_clock fallout
kgdb: Do not access xtime directly
powerpc: Clean up obsolete code relating to decrementer and timebase
powerpc: Rework VDSO gettimeofday to prevent time going backwards
clocksource: Add __clocksource_updatefreq_hz/khz methods
x86: Convert common clocksources to use clocksource_register_hz/khz
timekeeping: Make xtime and wall_to_monotonic static
hrtimer: Cleanup direct access to wall_to_monotonic
um: Convert to use read_persistent_clock
timkeeping: Fix update_vsyscall to provide wall_to_monotonic offset
powerpc: Cleanup xtime usage
powerpc: Simplify update_vsyscall
time: Kill off CONFIG_GENERIC_TIME
time: Implement timespec_add
x86: Fix vtime/file timestamp inconsistencies
Trivial conflicts in Documentation/feature-removal-schedule.txt
Much less trivial conflicts in arch/powerpc/kernel/time.c resolved as
per Thomas' earlier merge commit 47916be4e2 ("Merge branch
'powerpc.cherry-picks' into timers/clocksource")
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (27 commits)
sched: Use correct macro to display sched_child_runs_first in /proc/sched_debug
sched: No need for bootmem special cases
sched: Revert nohz_ratelimit() for now
sched: Reduce update_group_power() calls
sched: Update rq->clock for nohz balanced cpus
sched: Fix spelling of sibling
sched, cpuset: Drop __cpuexit from cpu hotplug callbacks
sched: Fix the racy usage of thread_group_cputimer() in fastpath_timer_check()
sched: run_posix_cpu_timers: Don't check ->exit_state, use lock_task_sighand()
sched: thread_group_cputime: Simplify, document the "alive" check
sched: Remove the obsolete exit_state/signal hacks
sched: task_tick_rt: Remove the obsolete ->signal != NULL check
sched: __sched_setscheduler: Read the RLIMIT_RTPRIO value lockless
sched: Fix comments to make them DocBook happy
sched: Fix fix_small_capacity
powerpc: Exclude arch_sd_sibiling_asym_packing() on UP
powerpc: Enable asymmetric SMT scheduling on POWER7
sched: Add asymmetric group packing option for sibling domain
sched: Fix capacity calculations for SMT4
sched: Change nohz idle load balancing logic to push model
...
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (162 commits)
tracing/kprobes: unregister_trace_probe needs to be called under mutex
perf: expose event__process function
perf events: Fix mmap offset determination
perf, powerpc: fsl_emb: Restore setting perf_sample_data.period
perf, powerpc: Convert the FSL driver to use local64_t
perf tools: Don't keep unreferenced maps when unmaps are detected
perf session: Invalidate last_match when removing threads from rb_tree
perf session: Free the ref_reloc_sym memory at the right place
x86,mmiotrace: Add support for tracing STOS instruction
perf, sched migration: Librarize task states and event headers helpers
perf, sched migration: Librarize the GUI class
perf, sched migration: Make the GUI class client agnostic
perf, sched migration: Make it vertically scrollable
perf, sched migration: Parameterize cpu height and spacing
perf, sched migration: Fix key bindings
perf, sched migration: Ignore unhandled task states
perf, sched migration: Handle ignored migrate out events
perf: New migration tool overview
tracing: Drop cpparg() macro
perf: Use tracepoint_synchronize_unregister() to flush any pending tracepoint call
...
Fix up trivial conflicts in Makefile and drivers/cpufreq/cpufreq.c
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
debug_core,kdb: fix crash when arch does not have single step
kgdb,x86: use macro HBP_NUM to replace magic number 4
kgdb,mips: remove unused kgdb_cpu_doing_single_step operations
mm,kdb,kgdb: Add a debug reference for the kdb kmap usage
KGDB: Remove set but unused newPC
ftrace,kdb: Allow dumping a specific cpu's buffer with ftdump
ftrace,kdb: Extend kdb to be able to dump the ftrace buffer
kgdb,powerpc: Replace hardcoded offset by BREAK_INSTR_SIZE
arm,kgdb: Add ability to trap into debugger on notify_die
gdbstub: do not directly use dbg_reg_def[] in gdb_cmd_reg_set()
gdbstub: Implement gdbserial 'p' and 'P' packets
kgdb,arm: Individual register get/set for arm
kgdb,mips: Individual register get/set for mips
kgdb,x86: Individual register get/set for x86
kgdb,kdb: individual register set and and get API
gdbstub: Optimize kgdb's "thread:" response for the gdb serial protocol
kgdb: remove custom hex_to_bin()implementation
