This patch introduces exclusive emergency stack for machine check exception.
We use emergency stack to handle machine check exception so that we can save
MCE information (srr1, srr0, dar and dsisr) before turning on ME bit and be
ready for re-entrancy. This helps us to prevent clobbering of MCE information
in case of nested machine checks.
The reason for using emergency stack over normal kernel stack is that the
machine check might occur in the middle of setting up a stack frame which may
result into improper use of kernel stack.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit 24ec2125f3 ("powerpc/xmon: Use cpumask iterator to avoid warning")
replaced a loop from 0 to NR_CPUS-1 with a for_each_possible_cpu() loop,
which means that if the last possible cpu is in xmon, we print the
wrong value for the end of the range. For example, if 4 cpus are
possible, NR_CPUS is 128, and all cpus are in xmon, we print "0-7f"
rather than "0-3". The code also assumes that the set of possible
cpus is contiguous, which may not necessarily be true.
This fixes the code to check explicitly for contiguity, and to print
the ending value correctly.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We haven't updated these for a while it seems, it's nice to have in the
oops output.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull powerpc update from Benjamin Herrenschmidt:
"The main highlights this time around are:
- A pile of addition POWER8 bits and nits, such as updated
performance counter support (Michael Ellerman), new branch history
buffer support (Anshuman Khandual), base support for the new PCI
host bridge when not using the hypervisor (Gavin Shan) and other
random related bits and fixes from various contributors.
- Some rework of our page table format by Aneesh Kumar which fixes a
thing or two and paves the way for THP support. THP itself will
not make it this time around however.
- More Freescale updates, including Altivec support on the new e6500
cores, new PCI controller support, and a pile of new boards support
and updates.
- The usual batch of trivial cleanups & fixes"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (156 commits)
powerpc: Fix build error for book3e
powerpc: Context switch the new EBB SPRs
powerpc: Turn on the EBB H/FSCR bits
powerpc: Replace CPU_FTR_BCTAR with CPU_FTR_ARCH_207S
powerpc: Setup BHRB instructions facility in HFSCR for POWER8
powerpc: Fix interrupt range check on debug exception
powerpc: Update tlbie/tlbiel as per ISA doc
powerpc: Print page size info during boot
powerpc: print both base and actual page size on hash failure
powerpc: Fix hpte_decode to use the correct decoding for page sizes
powerpc: Decode the pte-lp-encoding bits correctly.
powerpc: Use encode avpn where we need only avpn values
powerpc: Reduce PTE table memory wastage
powerpc: Move the pte free routines from common header
powerpc: Reduce the PTE_INDEX_SIZE
powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format
powerpc: New hugepage directory format
powerpc: Don't truncate pgd_index wrongly
powerpc: Don't hard code the size of pte page
powerpc: Save DAR and DSISR in pt_regs on MCE
...
Currently help message of /proc/sysrq-trigger highlight its
upper-case characters, like below:
SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E)
memory-full-oom-kill(F) kill-all-tasks(I) ...
this would confuse user trigger sysrq by upper-case character, which is
inconsistent with the real lower-case character registed key.
This inconsistent help message will also lead more confused when
26 upper-case letters put into use in future.
This patch fix powerpc xmon sysrq key: "xmon(x)"
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We were not saving DAR and DSISR on MCE. Save then and also print the values
along with exception details in xmon.
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With allmodconfig we are getting:
drivers/tty/synclink_gt.c:160:12: error: conflicting types for 'set_break'
arch/powerpc/include/asm/debug.h:49:5: note: previous declaration of 'set_break' was here
drivers/tty/synclinkmp.c:526:12: error: conflicting types for 'set_break'
arch/powerpc/include/asm/debug.h:49:5: note: previous declaration of 'set_break' was here
This renames set_break to set_breakpoint to avoid this naming conflict
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is a rewrite so that we don't assume we are using the DABR throughout the
code. We now use the arch_hw_breakpoint to store the breakpoint in a generic
manner in the thread_struct, rather than storing the raw DABR value.
The ptrace GET/SET_DEBUGREG interface currently passes the raw DABR in from
userspace. We keep this functionality, so that future changes (like the POWER8
DAWR), will still fake the DABR to userspace.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Finally remove the two level TOC and build with -mcmodel=medium.
Unfortunately we can't build modules with -mcmodel=medium due to
the tricks the kernel module loader plays with percpu data:
# -mcmodel=medium breaks modules because it uses 32bit offsets from
# the TOC pointer to create pointers where possible. Pointers into the
# percpu data area are created by this method.
#
# The kernel module loader relocates the percpu data section from the
# original location (starting with 0xd...) to somewhere in the base
# kernel percpu data space (starting with 0xc...). We need a full
# 64bit relocation for this to work, hence -mcmodel=large.
On older kernels we fall back to the two level TOC (-mminimal-toc)
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It is possible to configure a kernel which has xmon enabled, but has no
udbg backend to provide IO. This can make xmon rather confusing, as it
produces no output, blocks for two seconds, and then returns.
As a last resort we can instead try to printk(), which may deadlock or
otherwise crash, but tries quite hard not to.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently xmon_depth_to_print is static and global, but it's only
ever used in xmon_show_stack().
At least with a modern compiler it's inlined, so there's no point
in it being static, we could #define it but it's only used in one
place.
By reworking the logic we can drop count and just decrement the
max value as a loop counter. Also switch to a while loop so we
actually print no more than 64 frames as you'd expect based on the
variable name.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We use STACK_FRAME_OVERHEAD in the exception vectors to establish
the exception frame, so it should be good enough to use here.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Neither REGS_PER_LINE or LAST_VOLATILE are used, nor have they ever
been as far back as I can see.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have two #defines that rename scanhex() and skipbl() to
xmon_scanhex() and xmon_skipbl() - but no one ever uses those
names.
So the only effect is to rename the actual symbols in the generated
code, and AFACIS there is no reason to do that, so drop them.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The routines in start.c are only ever called from nonstdio.c, so if we
move them in there they can become static which is nice.
I suspect the idea behind the separation was that start.c could be
replaced in order to build xmon in userland. If anyone still cares about
doing that we could handle that with an ifdef or two.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
xmon_getchar() is only called from within nonstdio.c, so make it static.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This has been empty since 2005, commit 51d3082 "Unify udbg (#2)".
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It looks like xmon_expect() was used for doing xmon over a modem (!?),
that code was dropped in 2005 in commit 51d3082 "Unify udbg (#2)".
Once xmon_expect() is gone xmon_read_poll() is unused, drop it too.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This was originally motivated by a desire to see the mapping between
logical and hardware cpu numbers.
But it seemed that it made more sense to just add a command to dump
(most of) the paca.
With no arguments "dp" will dump the paca for the current cpu.
It also takes an argument, eg. "dp 3" which is the logical cpu number
in hex. This form does not check if the cpu is possible, but displays
the paca regardless, as well as the cpu's state in the possible, present
and online masks.
Thirdly, "dpa" will display the paca for all possible cpus. If there are
no possible cpus, like early in boot, it will tell you that.
Sample output, number in brackets is the offset into the struct:
2:mon> dp 3
paca for cpu 0x3 @ c00000000ff20a80:
possible = yes
present = yes
online = yes
lock_token = 0x8000 (0x8)
paca_index = 0x3 (0xa)
kernel_toc = 0xc00000000144f990 (0x10)
kernelbase = 0xc000000000000000 (0x18)
kernel_msr = 0xb000000000001032 (0x20)
stab_real = 0x0 (0x28)
stab_addr = 0x0 (0x30)
emergency_sp = 0xc00000003ffe4000 (0x38)
data_offset = 0xa40000 (0x40)
hw_cpu_id = 0x9 (0x50)
cpu_start = 0x1 (0x52)
kexec_state = 0x0 (0x53)
__current = 0xc00000007e568680 (0x218)
kstack = 0xc00000007e5a3e30 (0x220)
stab_rr = 0x1a (0x228)
saved_r1 = 0xc00000007e7cb450 (0x230)
trap_save = 0x0 (0x240)
soft_enabled = 0x0 (0x242)
irq_happened = 0x0 (0x243)
io_sync = 0x0 (0x244)
irq_work_pending = 0x0 (0x245)
nap_state_lost = 0x0 (0x246)
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rework set_dabr to take a DABRX value as well.
Both the pseries and PS3 hypervisors do some checks on the DABRX
values that are passed in the hcall. This patch stops bogus values
from being passed to hypervisor. Also, in the case where we are
clearing the breakpoint, where DABR and DABRX are zero, we modify the
DABRX value to make it valid so that the hcall won't fail.
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>
We have a bug report where the kernel hits a warning in the cpumask
code:
WARNING: at include/linux/cpumask.h:107
Which is:
WARN_ON_ONCE(cpu >= nr_cpumask_bits);
The backtrace is:
cpu_cmd
cmds
xmon_core
xmon
die
xmon is iterating through 0 to NR_CPUS. I'm not sure why we are still
open coding this but iterating above nr_cpu_ids is definitely a bug.
This patch iterates through all possible cpus, in case we issue a
system reset and CPUs in an offline state call in.
Perhaps the old code was trying to handle CPUs that were in the
partition but were never started (eg kexec into a kernel with an
nr_cpus= boot option). They are going to die way before we get into
xmon since we haven't set any kernel state up for them.
Signed-off-by: Anton Blanchard <anton@samba.org>
CC: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system
Pull "Disintegrate and delete asm/system.h" from David Howells:
"Here are a bunch of patches to disintegrate asm/system.h into a set of
separate bits to relieve the problem of circular inclusion
dependencies.
I've built all the working defconfigs from all the arches that I can
and made sure that they don't break.
The reason for these patches is that I recently encountered a circular
dependency problem that came about when I produced some patches to
optimise get_order() by rewriting it to use ilog2().
This uses bitops - and on the SH arch asm/bitops.h drags in
asm-generic/get_order.h by a circuituous route involving asm/system.h.
The main difficulty seems to be asm/system.h. It holds a number of
low level bits with no/few dependencies that are commonly used (eg.
memory barriers) and a number of bits with more dependencies that
aren't used in many places (eg. switch_to()).
These patches break asm/system.h up into the following core pieces:
(1) asm/barrier.h
Move memory barriers here. This already done for MIPS and Alpha.
(2) asm/switch_to.h
Move switch_to() and related stuff here.
(3) asm/exec.h
Move arch_align_stack() here. Other process execution related bits
could perhaps go here from asm/processor.h.
(4) asm/cmpxchg.h
Move xchg() and cmpxchg() here as they're full word atomic ops and
frequently used by atomic_xchg() and atomic_cmpxchg().
(5) asm/bug.h
Move die() and related bits.
(6) asm/auxvec.h
Move AT_VECTOR_SIZE_ARCH here.
Other arch headers are created as needed on a per-arch basis."
Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that. We'll find out anything that got broken and fix it..
* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
Delete all instances of asm/system.h
Remove all #inclusions of asm/system.h
Add #includes needed to permit the removal of asm/system.h
Move all declarations of free_initmem() to linux/mm.h
Disintegrate asm/system.h for OpenRISC
Split arch_align_stack() out from asm-generic/system.h
Split the switch_to() wrapper out of asm-generic/system.h
Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
Create asm-generic/barrier.h
Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
Disintegrate asm/system.h for Xtensa
Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
Disintegrate asm/system.h for Tile
Disintegrate asm/system.h for Sparc
Disintegrate asm/system.h for SH
Disintegrate asm/system.h for Score
Disintegrate asm/system.h for S390
Disintegrate asm/system.h for PowerPC
Disintegrate asm/system.h for PA-RISC
Disintegrate asm/system.h for MN10300
...
Disintegrate asm/system.h for PowerPC.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cc: linuxppc-dev@lists.ozlabs.org
"[RFC - PATCH 0/7] consolidation of BUG support code."
https://lkml.org/lkml/2012/1/26/525
--
The changes shown here are to unify linux's BUG support under
the one <linux/bug.h> file. Due to historical reasons, we have
some BUG code in bug.h and some in kernel.h -- i.e. the support for
BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h,
but old code in kernel.h wasn't moved to bug.h at that time. As
a band-aid, kernel.h was including <asm/bug.h> to pseudo link them.
This has caused confusion[1] and general yuck/WTF[2] reactions.
Here is an example that violates the principle of least surprise:
CC lib/string.o
lib/string.c: In function 'strlcat':
lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
make[2]: *** [lib/string.o] Error 1
$
$ grep linux/bug.h lib/string.c
#include <linux/bug.h>
$
We've included <linux/bug.h> for the BUG infrastructure and yet we
still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.]
Ugh - very confusing for someone who is new to kernel development.
With the above in mind, the goals of this changeset are:
1) find and fix any include/*.h files that were relying on the
implicit presence of BUG code.
2) find and fix any C files that were consuming kernel.h and
hence relying on implicitly getting some/all BUG code.
3) Move the BUG related code living in kernel.h to <linux/bug.h>
4) remove the asm/bug.h from kernel.h to finally break the chain.
During development, the order was more like 3-4, build-test, 1-2.
But to ensure that git history for bisect doesn't get needless
build failures introduced, the commits have been reorderd to fix
the problem areas in advance.
[1] https://lkml.org/lkml/2012/1/3/90
[2] https://lkml.org/lkml/2012/1/17/414
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Merge tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
Pull <linux/bug.h> cleanup from Paul Gortmaker:
"The changes shown here are to unify linux's BUG support under the one
<linux/bug.h> file. Due to historical reasons, we have some BUG code
in bug.h and some in kernel.h -- i.e. the support for BUILD_BUG in
linux/kernel.h predates the addition of linux/bug.h, but old code in
kernel.h wasn't moved to bug.h at that time. As a band-aid, kernel.h
was including <asm/bug.h> to pseudo link them.
This has caused confusion[1] and general yuck/WTF[2] reactions. Here
is an example that violates the principle of least surprise:
CC lib/string.o
lib/string.c: In function 'strlcat':
lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON'
make[2]: *** [lib/string.o] Error 1
$
$ grep linux/bug.h lib/string.c
#include <linux/bug.h>
$
We've included <linux/bug.h> for the BUG infrastructure and yet we
still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh -
very confusing for someone who is new to kernel development.
With the above in mind, the goals of this changeset are:
1) find and fix any include/*.h files that were relying on the
implicit presence of BUG code.
2) find and fix any C files that were consuming kernel.h and hence
relying on implicitly getting some/all BUG code.
3) Move the BUG related code living in kernel.h to <linux/bug.h>
4) remove the asm/bug.h from kernel.h to finally break the chain.
During development, the order was more like 3-4, build-test, 1-2. But
to ensure that git history for bisect doesn't get needless build
failures introduced, the commits have been reorderd to fix the problem
areas in advance.
[1] https://lkml.org/lkml/2012/1/3/90
[2] https://lkml.org/lkml/2012/1/17/414"
Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul
and linux-next.
* tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
kernel.h: doesn't explicitly use bug.h, so don't include it.
bug: consolidate BUILD_BUG_ON with other bug code
BUG: headers with BUG/BUG_ON etc. need linux/bug.h
bug.h: add include of it to various implicit C users
lib: fix implicit users of kernel.h for TAINT_WARN
spinlock: macroize assert_spin_locked to avoid bug.h dependency
x86: relocate get/set debugreg fcns to include/asm/debugreg.
This is no longer selectable, so just remove all the dependent code.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current implementation of lazy interrupts handling has some
issues that this tries to address.
We don't do the various workarounds we need to do when re-enabling
interrupts in some cases such as when returning from an interrupt
and thus we may still lose or get delayed decrementer or doorbell
interrupts.
The current scheme also makes it much harder to handle the external
"edge" interrupts provided by some BookE processors when using the
EPR facility (External Proxy) and the Freescale Hypervisor.
Additionally, we tend to keep interrupts hard disabled in a number
of cases, such as decrementer interrupts, external interrupts, or
when a masked decrementer interrupt is pending. This is sub-optimal.
This is an attempt at fixing it all in one go by reworking the way
we do the lazy interrupt disabling from the ground up.
The base idea is to replace the "hard_enabled" field with a
"irq_happened" field in which we store a bit mask of what interrupt
occurred while soft-disabled.
When re-enabling, either via arch_local_irq_restore() or when returning
from an interrupt, we can now decide what to do by testing bits in that
field.
We then implement replaying of the missed interrupts either by
re-using the existing exception frame (in exception exit case) or via
the creation of a new one from an assembly trampoline (in the
arch_local_irq_enable case).
This removes the need to play with the decrementer to try to create
fake interrupts, among others.
In addition, this adds a few refinements:
- We no longer hard disable decrementer interrupts that occur
while soft-disabled. We now simply bump the decrementer back to max
(on BookS) or leave it stopped (on BookE) and continue with hard interrupts
enabled, which means that we'll potentially get better sample quality from
performance monitor interrupts.
- Timer, decrementer and doorbell interrupts now hard-enable
shortly after removing the source of the interrupt, which means
they no longer run entirely hard disabled. Again, this will improve
perf sample quality.
- On Book3E 64-bit, we now make the performance monitor interrupt
act as an NMI like Book3S (the necessary C code for that to work
appear to already be present in the FSL perf code, notably calling
nmi_enter instead of irq_enter). (This also fixes a bug where BookE
perfmon interrupts could clobber r14 ... oops)
- We could make "masked" decrementer interrupts act as NMIs when doing
timer-based perf sampling to improve the sample quality.
Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2:
- Add hard-enable to decrementer, timer and doorbells
- Fix CR clobber in masked irq handling on BookE
- Make embedded perf interrupt act as an NMI
- Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want
to retrigger an interrupt without preventing hard-enable
v3:
- Fix or vs. ori bug on Book3E
- Fix enabling of interrupts for some exceptions on Book3E
v4:
- Fix resend of doorbells on return from interrupt on Book3E
v5:
- Rebased on top of my latest series, which involves some significant
rework of some aspects of the patch.
v6:
- 32-bit compile fix
- more compile fixes with various .config combos
- factor out the asm code to soft-disable interrupts
- remove the C wrapper around preempt_schedule_irq
v7:
- Fix a bug with hard irq state tracking on native power7
Also use local_paca instead of get_paca() to avoid getting into
the smp_processor_id() debugging code from the debugger
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With bug.h currently living right in linux/kernel.h there
are files that use BUG_ON and friends but are not including
the header explicitly. Fix them up so we can remove the
presence in kernel.h file.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The 'u' command will print the TLB on book3e parts and the SLB on
Book3s parts, but the help system doesn't say that correctly.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
All these files were including module.h just for the basic
EXPORT_SYMBOL infrastructure. We can shift them off to the
export.h header which is a way smaller footprint and thus
realize some compile time gains.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Based on patch by David Gibson <dwg@au1.ibm.com>
xmon has a longstanding bug on systems which are SMP-capable but lack
the MSR[RI] bit. In these cases, xmon invoked by IPI on secondary
CPUs will not properly keep quiet, but will print stuff, thereby
garbling the primary xmon's output. This patch fixes it, by ignoring
the RI bit if the processor does not support it.
There's already a version of this for 4xx upstream, which we'll need
to extend to other RI-lacking CPUs at some point. For now this adds
Book3e processors to the mix.
Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The only user of MSG_ALL_BUT_SELF in the whole kernel tree is powerpc,
and it only uses it to start the debugger. Both debuggers always call
smp_send_debugger_break with MSG_ALL_BUT_SELF, and only mpic can do
anything more optimal than a loop over all online cpus, but all message
passing implementations have to code for this special delivery target.
Convert smp_send_debugger_break to take void and loop calling the smp_ops
message_pass function for each of the other cpus in the online cpumask.
Use raw_smp_processor_id() because we are either entering the debugger
or trying to start kdump and the additional warning it not useful were
it to trigger.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Adapt new API.
Almost change is trivial. Most important change is the below line
because we plan to change task->cpus_allowed implementation.
- ctx->cpus_allowed = current->cpus_allowed;
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Recent 64-bit server processors (POWER6 and POWER7) have a "Come-From
Address Register" (CFAR), that records the address of the most recent
branch or rfid (return from interrupt) instruction for debugging purposes.
This saves the value of the CFAR in the exception entry code and stores
it in the exception frame. We also make xmon print the CFAR value in
its register dump code.
Rather than extend the pt_regs struct at this time, we steal the orig_gpr3
field, which is only used for system calls, and use it for the CFAR value
for all exceptions/interrupts other than system calls. This means we
don't save the CFAR on system calls, which is not a great problem since
system calls tend not to happen unexpectedly, and also avoids adding the
overhead of reading the CFAR to the system call entry path.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some of the 64bit PPC CPU features are MMU-related, so this patch moves
them to MMU_FTR_ bits. All cpu_has_feature()-style tests are moved to
mmu_has_feature(), and seven feature bits are freed as a result.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use the new MSR_64BIT in a few places. Some of these are already ifdef'ed
for BOOKE vs BOOKS, but it's still clearer, MSR_SF does not immediately
parse as "MSR bit for 64bit".
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Commit ddd588b5dd ("oom: suppress nodes that are not allowed from
meminfo on oom kill") moved lib/show_mem.o out of lib/lib.a, which
resulted in build warnings on all architectures that implement their own
versions of show_mem():
lib/lib.a(show_mem.o): In function `show_mem':
show_mem.c:(.text+0x1f4): multiple definition of `show_mem'
arch/sparc/mm/built-in.o:(.text+0xd70): first defined here
The fix is to remove __show_mem() and add its argument to show_mem() in
all implementations to prevent this breakage.
Architectures that implement their own show_mem() actually don't do
anything with the argument yet, but they could be made to filter nodes
that aren't allowed in the current context in the future just like the
generic implementation.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: James Bottomley <James.Bottomley@hansenpartnership.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace EXTRA_CFLAGS with ccflags-y and EXTRA_AFLAGS with asflags-y.
Signed-off-by: matt mooney <mfm@muteddisk.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Noone is using tty argument so let's get rid of it.
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Using perf to trace L1 dcache misses and dumping data addresses I found a few
variables taking a lot of misses. Since they are almost never written, they
should go into the __read_mostly section.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch provides an extended_cede_processor() helper function
which takes the cede latency hint as an argument. This hint is to be passed
on to the hypervisor to cede to the corresponding state on platforms
which support it.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Arun R Bharadwaj <arun@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Prior to the arch/ppc -> arch/powerpc transition, xmon had support for single
stepping on 4xx boards. The functionality was lost when arch/ppc was removed.
This patch restores single step support for 44x boards, and Book-E in general.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The xmon code relies on MSR_RI being non-zero to indicate that an exception
is recoverable. If it is not, it prints a warning message. However, the
PowerPC 4xx cores do not have an MSR_RI bit and this warning is produced for
every xmon event.
This introduces an unrecoverable_excp function to determine if an exception
is recoverable or not. This gets rid of the erroneous warnings on 4xx.
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Make it possible to enable GCOV code coverage measurement on powerpc.
Lightly tested on 64-bit, seems to work as expected.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This contains all the bits that didn't fit in previous patches :-) This
includes the actual exception handlers assembly, the changes to the
kernel entry, other misc bits and wiring it all up in Kconfig.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add the option to build the code under arch/powerpc with -Werror.
The intention is to make it harder for people to inadvertantly introduce
warnings in the arch/powerpc code. It needs to be configurable so that
if a warning is introduced, people can easily work around it while it's
being fixed.
The option is a negative, ie. don't enable -Werror, so that it will be
turned on for allyes and allmodconfig builds.
The default is n, in the hope that developers will build with -Werror,
that will probably lead to some build breaks, I am prepared to be flamed.
It's not enabled for math-emu, which is a steaming pile of warnings.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Gets rid of this warning:
arch/powerpc/xmon/xmon.c: In function 'dump_log_buf':
arch/powerpc/xmon/xmon.c:2133: warning: unused variable 'i'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Hello All,
Quite a while back Michael Ellerman had posted a patch to add support to xmon to print the contents of the console log pointed to by __log_buf.
Here's the link to that patch - http://ozlabs.org/pipermail/linuxppc64-dev/2005-March/003657.html
I've ported the patch in the above link to 2.6.30-rc5 and have tested it.
Thanks & regards,
Vinay
Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Today the arch/powerpc/xmon/setjmp.S file contains only the
xmon_save_regs function. We want to use it for kdump purposes, so
let's move the file into arch/powerpc/kernel/ and give the function a
more generic name (ppc_save_regs).
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes sure we don't try to call find_bug or is_warning_bug when
CONFIG_BUG=n and CONFIG_XMON=y. Otherwise we get these errors:
arch/powerpc/xmon/xmon.c: In function ‘print_bug_trap’:
arch/powerpc/xmon/xmon.c:1364: error: implicit declaration of function ‘find_bug’
arch/powerpc/xmon/xmon.c:1364: warning: assignment makes pointer from integer without a cast
arch/powerpc/xmon/xmon.c:1367: error: implicit declaration of function ‘is_warning_bug’
arch/powerpc/xmon/xmon.c:1374: error: dereferencing pointer to incomplete type
make[2]: *** [arch/powerpc/xmon/xmon.o] Error 1
make[1]: *** [arch/powerpc/xmon] Error 2
make: *** [sub-make] Error 2
Signed-off-by: Paul Mackerras <paulus@samba.org>
According to the CBEA, the SPU dsisr is not updated for class 0
exceptions.
spu_stopped() is testing the dsisr that was passed to it from the class
0 exception handler, so we return a false positive here.
This patch cleans up the interrupt handler and erroneous tests in
spu_stopped. It also removes the fields from the csa since it is not
needed to process class 0 events.
Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
This is a little messier than I'd like because xmon.h only exists
on powerpc and we can't have a static inline and an extern declaration
visible at the same time.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
warning: Using plain integer as NULL pointer
warning: Using plain integer as NULL pointer
warning: symbol 'excprint' was not declared. Should it be static?
warning: symbol 'prregs' was not declared. Should it be static?
warning: symbol 'cacheflush' was not declared. Should it be static?
warning: symbol 'read_spr' was not declared. Should it be static?
warning: symbol 'write_spr' was not declared. Should it be static?
warning: symbol 'super_regs' was not declared. Should it be static?
warning: symbol 'mread' was not declared. Should it be static?
warning: symbol 'mwrite' was not declared. Should it be static?
warning: symbol 'byterev' was not declared. Should it be static?
warning: symbol 'memex' was not declared. Should it be static?
warning: symbol 'bsesc' was not declared. Should it be static?
warning: symbol 'dump' was not declared. Should it be static?
warning: symbol 'prdump' was not declared. Should it be static?
warning: symbol 'generic_inst_dump' was not declared. Should it be static?
warning: symbol 'ppc_inst_dump' was not declared. Should it be static?
warning: symbol 'memops' was not declared. Should it be static?
warning: symbol 'memdiffs' was not declared. Should it be static?
warning: symbol 'memlocate' was not declared. Should it be static?
warning: symbol 'memzcan' was not declared. Should it be static?
warning: symbol 'proccall' was not declared. Should it be static?
warning: symbol 'scannl' was not declared. Should it be static?
warning: symbol 'hexdigit' was not declared. Should it be static?
warning: symbol 'flush_input' was not declared. Should it be static?
warning: symbol 'inchar' was not declared. Should it be static?
warning: symbol 'take_input' was not declared. Should it be static?
warning: symbol 'xmon_init' was not declared. Should it be static?
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
SPU class 0 & 1 exceptions may occur in parallel, so we may end up
overwriting csa.dsisr.
This change adds dedicated fields for each class to the spu and the spu
context so that fault data is not overwritten.
Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
This moves various definitions used all over the place to parse stack
frames to ptrace.h so only one definition is needed.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that we have the alpaca, the reg_save_ptr is no longer needed in the
paca. Eradicate all global uses of it and make it static in the iSeries
lpardata.c
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes the setjmp/longjmp code used by xmon, generically available
to other code. It also removes the requirement for debugger hooks to
be only called on 0x300 (data storage) exception.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Currently we hardwire the number of SLBs to 64, but PAPR says we
should use the ibm,slb-size property to obtain the number of SLB
entries. This uses this property instead of assuming 64. If no
property is found, we assume 64 entries as before.
This soft patches the SLB handler, so it shouldn't change performance
at all.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds a function to xmon to dump the content of the 44x processor
TLB with a little bit of decoding (but not much).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In some configuration, xmon help string is larger than xmon_printf
buffer. We need not to use printf. This patch adds xmon_puts and
change to use it to show help string.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Because xmon_write doesn't change the buffer, we should add 'const'
qualifier to the argument which points it.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Several kallsyms_lookup() pass dummy arguments but only need, say, module's
name. Make kallsyms_lookup() accept NULLs where possible.
Also, makes picture clearer about what interfaces are needed for all symbol
resolving business.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Whenever we enter xmon we get a WARN_ON out of the rtas code since it
thinks interrupts are still on:
Unable to handle kernel paging request for data at address 0x00000000
Faulting instruction address: 0xd000000000080008
cpu 0x3: Vector: 300 (Data Access) at [c0000000075dba00]
pc: d000000000080008: .doit+0x8/0x40 [oopser]
lr: c000000000077704: .sys_init_module+0x1664/0x1824
sp: c0000000075dbc80
msr: 9000000000009032
dar: 0
dsisr: 42000000
current = 0xc000000003fa64b0
paca = 0xc000000000694280
pid = 2260, comm = insmod
------------[ cut here ]------------
Badness at arch/powerpc/kernel/entry_64.S:651
Call Trace:
[C0000000075DAE70] [C00000000000EB64] .show_stack+0x68/0x1b0 (unreliable)
[C0000000075DAF10] [C000000000216254] .report_bug+0x94/0xe8
[C0000000075DAFA0] [C00000000047B140] __kprobes_text_start+0x178/0x584
[C0000000075DB040] [C0000000000044F4] program_check_common+0xf4/0x100
Signed-off-by: Paul Mackerras <paulus@samba.org>
My patch to add spu disassembly (af89fb8041)
removed a newline from the xmon help that it shouldn't have, put it back.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It doesn't make any sense to have a priority field in the physical spu
structure. Move it into the spu context instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Use ARRAY_SIZE macro already defined in linux/kernel.h
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes powerpc use the generic BUG machinery. The biggest reports the
function name, since it is redundant with kallsyms, and not needed in general.
There is an overall reduction of code, since module_32/64 duplicated several
functions.
Unfortunately there's no way to tell gcc that BUG won't return, so the BUG
macro includes a goto loop. This will generate a real jmp instruction, which
is never used.
[akpm@osdl.org: build fix]
[paulus@samba.org: remove infinite loop in BUG_ON]
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
xmon still does not run on iSeries, but this allows us to build a combined
kernel that includes it.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It may be desireable to build a kernel for cell without
spufs, e.g. as the initial kboot kernel. This requires
that the SPU specific parts of the core dump and the xmon
code depend on CONFIG_SPU_BASE instead of CONFIG_PPC_CELL.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This fixes the xmon support for the cell spu to be compatable with the split
spu platform code.
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This includes:
* version 1.24 of ppc-dis.c
* version 1.88 of ppc-opc.c
* version 1.23 of ppc.h
I can't vouch for the accuracy etc. of these changes, but it brings
us into line with binutils - and from a cursory test appears to work
fine.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
While adding spu disassembly support it struck me that we're actually
carrying quite a lot of code around, just to do disassembly in the case
of a crash.
While on large systems it's not an issue, on smaller ones it might be
nice to have xmon - but without the weight of the disassembly support.
For a Cell build this saves ~230KB (!), and for pSeries ~195KB.
We still support the 'di' and 'sdi' commands, however they just dump
the instruction in hex.
Move the definitions into a header to clean xmon.c just a tiny bit.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch adds a "sdi" command to xmon, to disassemble the contents
of an spu's local store.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch imports and munges the spu disassembly code from binutils.
All files originated from version 1.1 in binutils cvs.
* spu.h, spu-insns.h and spu-opc.c are unchanged except for pathnames.
* spu-dis.c has been edited heavily:
* use printf instead of info->fprintf_func and similar.
* pass the instruction in rather than reading it.
* we have no equivalent to symbol_at_address_func, so we just assume
there is never a symbol at the address given.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
In order to do disassembly of spu binaries in xmon, we need to abstract
the disassembly function from ppc_inst_dump.
We do this by making the actual disassembly function a function pointer
that we pass to ppc_inst_dump(). To save updating all the callers, we
turn ppc_inst_dump() into generic_inst_dump() and make ppc_inst_dump()
a wrapper which always uses print_insn_powerpc().
Currently we pass the dialect into print_insn_powerpc(), but we always
pass 0 - so just make it a local.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Add a command to xmon to dump the memory of a spu's local store.
This mimics the 'd' command which dumps regular memory, but does
a little hand holding by taking the user supplied address and
finding that offset in the local store for the specified spu.
This makes it easy for example to look at what was executing on a spu:
1:mon> ss
...
Stopped spu 04 (was running)
...
1:mon> sf 4
Dumping spu fields at address c0000000019e0a00:
...
problem->spu_npc_RW = 0x228
...
1:mon> sd 4 0x228
d000080080318228 01a00c021cffc408 4020007f217ff488 |........@ ..!...|
Aha, 01a00c02, which is of course rdch $2,$ch24 !
--
Updated to only do the setjmp goo around the spu access, and not
around prdump because it does its own (via mread).
Also the num variable is now common between sf and sd, so you don't
have to keep typing the spu number in if you're repeating commands
on the same spu.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
After stopping spus in xmon I often find myself trawling through the
field dumps to find out which spus were running. The spu stopping
code actually knows what's running, so let's print it out to save
the user some futzing.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
My patch to add spu helpers to xmon (a898497088)
introduced a few sparse warnings, because I was dereferencing an __iomem
pointer.
I think the best way to handle it is to actually use the appropriate in_beXX
functions. Need to rejigger the DUMP macro a little to accomodate that.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This patch adds a command to xmon for dumping information about
spu structs. The command is 'sf' for "spu fields" perhaps, and
takes the spu number as an argument. This is the same value as the
spu->number field, or the "phys-id" value of a context when it is
bound to a physical spu.
We try to catch memory errors as we dump each field, hopefully this
will make the command reasonably robust, but YMMV. If people see a
need we can easily add more fields to the dump in future.
Output looks something like this:
0:mon> sf 0
Dumping spu fields at address c00000001ffd9e80:
number = 0x0
name = spe
devnode->full_name = /cpus/PowerPC,BE@0/spes/spe@0
nid = 0x0
local_store_phys = 0x20000000000
local_store = 0xd0000800801e0000
ls_size = 0x0
isrc = 0x4
node = 0x0
flags = 0x0
dar = 0x0
dsisr = 0x0
class_0_pending = 0
irqs[0] = 0x16
irqs[1] = 0x17
irqs[2] = 0x24
slb_replace = 0x0
pid = 0
prio = 0
mm = 0x0000000000000000
ctx = 0x0000000000000000
rq = 0x0000000000000000
timestamp = 0x0000000000000000
problem_phys = 0x20000040000
problem = 0xd000080080220000
problem->spu_runcntl_RW = 0x0
problem->spu_status_R = 0x0
problem->spu_npc_RW = 0x0
priv1 = 0xd000080080240000
priv1->mfc_sr1_RW = 0x33
priv2 = 0xd000080080250000
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch adds support for stopping, and restarting, spus
from xmon. We use the spu master runcntl bit to stop execution,
this is apparently the "right" way to control spu execution and
spufs will be changed in the future to use this bit.
Testing has shown that to restart execution we have to turn the
master runcntl bit on and also rewrite the spu runcntl bit, even
if it is already set to 1 (running).
Stopping spus is triggered by the xmon command 'ss' - "spus stop"
perhaps. Restarting them is triggered via 'sr'. Restart doesn't
start execution on spus unless they were running prior to being
stopped by xmon.
Walking the spu->full_list in xmon after a panic, would mean
corruption of any spu struct would make all the others
inaccessible. To avoid this, and also to make the next patch
easier, we cache pointers to all spus during boot.
We attempt to catch and recover from errors while stopping and
restarting the spus, but as with most xmon functionality there are
no guarantees that performing these operations won't crash xmon
itself.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Currently, if xmon has no input device (as is generally the case on
G5 powermacs), and we drop into xmon as a result of a fatal exception,
it will return 1, which die() interprets as "continue without causing
an oops". This fixes it by making xmon() return 0 in the case where
it has no input device.
Signed-off-by: Paul Mackerras <paulus@samba.org>
My patch to make the early xmon logic work with earlier early param
parsing (480f6f35a1) breaks xmon=off.
No one does this obviously as xmon rocks, but it should really work
as documented.
While fixing that it struck me that we could move the xmon param
handling into xmon.c, and also consolidate the
xmon_init()/do_early_xmon logic into xmon_setup(). This means
xmon=early drops into xmon a little earlier on 32-bit, but it
seems to work just fine.
Tested on PSERIES and CLASSIC32.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
xmon does not print a backtrace per default. This is bad on systems with
USB keyboard, the most needed info about the crash is lost.
print a backtrace during the very first xmon entry.
Booting with xmon=nobt disables the autobacktrace functionality.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch contains a total rewrite of the backlight infrastructure for
portable Apple computers. Backward compatibility is retained. A sysfs
interface allows userland to control the brightness with more steps than
before. Userland is allowed to upload a brightness curve for different
monitors, similar to Mac OS X.
[akpm@osdl.org: add needed exports]
Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Dump a stream of rawbytes with a new 'dr' command.
Produces less output and it is simpler to feed the output to scripts.
Also, dr has no dumpsize limits.
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These symbols are only used in the file that they are defined in,
so they should not be in the global namespace.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
There's a bunch of code that compares an address with KERNELBASE to see if
it's a "kernel address", ie. >= KERNELBASE. The proper test is actually to
compare with PAGE_OFFSET, since we're going to change KERNELBASE soon.
So replace all of them with an is_kernel_addr() macro that does that.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The udbg low level io layer has an issue with udbg_getc() returning a
char (unsigned on ppc) instead of an int, thus the -1 if you had no
available input device could end up turned into 0xff, filling your
display with bogus characters. This fixes it, along with adding a little
blob to xmon to do a delay before exiting when getting an EOF and fixing
the detection of ADB keyboards in udbg_adb.c
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch unifies udbg for both ppc32 and ppc64 when building the
merged achitecture. xmon now has a single "back end". The powermac udbg
stuff gets enriched with some ADB capabilities and btext output. In
addition, the early_init callback is now called on ppc32 as well,
approx. in the same order as ppc64 regarding device-tree manipulations.
The init sequences of ppc32 and ppc64 are getting closer, I'll unify
them in a later patch.
For now, you can force udbg to the scc using "sccdbg" or to btext using
"btextdbg" on powermacs. I'll implement a cleaner way of forcing udbg
output to something else than the autodetected OF output device in a
later patch.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
arch/powerpc/xmon/xmon.c:525: error: syntax error before "xmon_irq"
arch/powerpc/xmon/xmon.c:526: warning: return type defaults to `int'
arch/powerpc/xmon/xmon.c: In function `xmon_irq':
arch/powerpc/xmon/xmon.c:532: error: `IRQ_HANDLED' undeclared (first use in this function)
arch/powerpc/xmon/xmon.c:532: error: (Each undeclared identifier is reported only once
arch/powerpc/xmon/xmon.c:532: error: for each function it appears in.)
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When we created the instructions to read/write SPRs in xmon, we were
setting up a ppc64-style procedure descriptor and calling that, which
doesn't work in 32-bit. For 32-bit a function pointer just points
to the instructions of the function. This fixes it to do the right
thing for both 32-bit and 64-bit.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This makes the memory examine/change command print the address as
8 digits instead of 16, and makes the memory dump command print
4 4-byte values per line instead of 2 8-byte values.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch consolidates macros used to generate assembly for
compatibility across different CPUs or configs. A new header,
asm-powerpc/asm-compat.h contains the main compatibility macros. It
uses some preprocessor magic to make the macros suitable both for use
in .S files, and in inline asm in .c files. Headers (bitops.h,
uaccess.h, atomic.h, bug.h) which had their own such compatibility
macros are changed to use asm-compat.h.
ppc_asm.h is now for use in .S files *only*, and a #error enforces
that. As such, we're a lot more careless about namespace pollution
here than in asm-compat.h.
While we're at it, this patch adds a call to the PPC405_ERR77 macro in
futex.h which should have had it already, but didn't.
Built and booted on pSeries, Maple and iSeries (ARCH=powerpc). Built
for 32-bit powermac (ARCH=powerpc) and Walnut (ARCH=ppc).
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This factors out the common bits of arch/powerpc/xmon/start_*.c into
a new nonstdio.c, and removes some stuff that was supposed to make
xmon's I/O routines somewhat stdio-like but was never used.
It also makes the parsing of the xmon= command line option common,
so that ppc32 can now use xmon={off,on,early} also.
Signed-off-by: Paul Mackerras <paulus@samba.org>
The merged version follows the ppc64 version pretty closely mostly,
and in fact ARCH=ppc64 now uses the arch/powerpc/xmon version.
The main difference for ppc64 is that the 'p' command to call
show_state (which was always pretty dodgy) has been replaced by
the ppc32 'p' command, which calls a given procedure (so in fact
the old 'p' command behaviour can be achieved with 'p $show_state').
Signed-off-by: Paul Mackerras <paulus@samba.org>
Mahesh Salgaonkar