It has been suggested that I add a way to disable the function tracer
on an oops. This code adds a ftrace_kill_atomic. It is not meant to be
used in normal situations. It will disable the ftrace tracer, but will
not perform the nice shutdown that requires scheduling.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is more of a clean up. Currently the function tracer initializes the
tracer with which ever CPU was last used for tracing. This value isn't
realy useful for function tracing, but at least it should be something other
than a random number.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Enabling the wakeup tracer before enabling the function tracing causes
some strange results due to the dynamic enabling of the functions.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There is no CONFIG_PREEMPT_DESKTOP. Use the proper entry CONFIG_PREEMPT.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
After the sched_clock code has been removed from sched.c we can now trace
the scheduler. The scheduler has a lot of functions that would be worth
tracing.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When CONFIG_FTRACE is not enabled, the tracing_start_functon_trace
and tracing_stop_function_trace should be nops.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We have two markers now that are enabled on sched_switch. One that records
the context switching and the other that records task wake ups. Currently
we enable the tracing first and then set the markers. This causes some
confusing traces:
# tracer: sched_switch
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
trace-cmd-3973 [00] 115.834817: 3973:120:R + 3: 0:S
trace-cmd-3973 [01] 115.834910: 3973:120:R + 6: 0:S
trace-cmd-3973 [02] 115.834910: 3973:120:R + 9: 0:S
trace-cmd-3973 [03] 115.834910: 3973:120:R + 12: 0:S
trace-cmd-3973 [02] 115.834910: 3973:120:R + 9: 0:S
<idle>-0 [02] 115.834910: 0:140:R ==> 3973:120:R
Here we see that trace-cmd with PID 3973 wakes up task 9 but the next line
shows the idle task doing a context switch to task 3973.
Enabling the tracing to _after_ the markers are set creates a much saner
output:
# tracer: sched_switch
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
<idle>-0 [02] 7922.634225: 0:140:R ==> 4790:120:R
trace-cmd-4789 [03] 7922.634225: 0:140:R + 4790:120:R
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use the X86_FEATURE_SYSENTER32 to remove hard-coded CPU vendor check.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add pseudo-feature bits to describe whether the CPU supports sysenter
and/or syscall from ia32-compat userspace. This removes a hardcoded
test in vdso32-setup.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The problem is introduced by commit
664d080c41.
acpi_evaluate_integer is a sleeping function,
and it should not be called with spin_lock_irqsave.
https://bugzilla.redhat.com/show_bug.cgi?id=451399
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Some BIOSen enable DIPM via _GTF which causes command timeouts under
certain configuration. This didn't occur on 2.6.25 because 2.6.25
defaulted to SRST, so _GTF wasn't executed during boot probe, so ahci
host reset disabled DIPM and as _GTF wasn't executed after SRST, DIPM
wasn't enabled. On 2.6.26, hardreset is used during probe and after
probe _GTF is executed enabling DIPM and thus the failures.
This patch could theoretically disable DIPM on machines which used to
have it enabled on 2.6.25 but AFAIK ahci is currently the only driver
which uses SATA ACPI hierarchy (_SDD) and as the host reset would have
always disabled DIPM, this shouldn't happen.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Yinghai Lu reported crashes on 64-bit x86:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
IP: [<ffffffff80253b17>] hrtick_start_fair+0x89/0x173
[...]
And with a long session of debugging and a lot of difficulty, tracked it down
to this commit:
--------------->
8fbbc4b45c is first bad commit
commit 8fbbc4b45c
Author: Alok Kataria <akataria@vmware.com>
Date: Tue Jul 1 11:43:34 2008 -0700
x86: merge tsc_init and clocksource code
<--------------
The problem is that the TSC unification missed these Makefile rules
in arch/x86/kernel/Makefile:
# Do not profile debug and lowlevel utilities
CFLAGS_REMOVE_tsc_64.o = -pg
CFLAGS_REMOVE_tsc_32.o = -pg
...
CFLAGS_tsc_64.o := $(nostackp)
...
which rules make sure that various instrumentation and debugging
facilities are disabled for code that might end up in a VDSO - such as
the TSC code.
Reported-and-bisected-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Conflicts:
Signed-off-by: Ingo Molnar <mingo@elte.hu>
when more than 4g memory is installed, don't map the big hole below 4g.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
save the SLIT, in case we are using fixmap to read it, and that fixmap
could be cleared by others.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
also let mem= to print out modified e820 map too
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The IRQ rate reported back by the RTC is incorrect when HPET is enabled.
Newer hardware that has HPET to emulate the legacy RTC device gets this value
wrong since after it sets the rate, it returns before setting the variable
used to report the IRQ rate back to users of the device -- so the set rate and
the reported rate get out of sync.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Brownell <david-b@pacbell.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (27 commits)
tun: Persistent devices can get stuck in xoff state
xfrm: Add a XFRM_STATE_AF_UNSPEC flag to xfrm_usersa_info
ipv6: missed namespace context in ipv6_rthdr_rcv
netlabel: netlink_unicast calls kfree_skb on error path by itself
ipv4: fib_trie: Fix lookup error return
tcp: correct kcalloc usage
ip: sysctl documentation cleanup
Documentation: clarify tcp_{r,w}mem sysctl docs
netfilter: nf_nat_snmp_basic: fix a range check in NAT for SNMP
netfilter: nf_conntrack_tcp: fix endless loop
libertas: fix memory alignment problems on the blackfin
zd1211rw: stop beacons on remove_interface
rt2x00: Disable synchronization during initialization
rc80211_pid: Fix fast_start parameter handling
sctp: Add documentation for sctp sysctl variable
ipv6: fix race between ipv6_del_addr and DAD timer
irda: Fix netlink error path return value
irda: New device ID for nsc-ircc
irda: via-ircc proper dma freeing
sctp: Mark the tsn as received after all allocations finish
...
The scenario goes like this. App stops reading from tun/tap.
TX queue gets full and driver does netif_stop_queue().
App closes fd and TX queue gets flushed as part of the cleanup.
Next time the app opens tun/tap and starts reading from it but
the xoff state is not cleared. We're stuck.
Normally xoff state is cleared when netdev is brought up. But
in the case of persistent devices this happens only during
initial setup.
The fix is trivial. If device is already up when an app opens
it we clear xoff state and that gets things moving again.
Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a XFRM_STATE_AF_UNSPEC flag to handle the AF_UNSPEC behavior for
the selector family. Userspace applications can set this flag to leave
the selector family of the xfrm_state unspecified. This can be used
to to handle inter family tunnels if the selector is not set from
userspace.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
So, no need to kfree_skb here on the error path. In this case we can
simply return.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit a07f5f508a "[IPV4] fib_trie: style
cleanup", the changes to check_leaf() and fn_trie_lookup() were wrong - where
fn_trie_lookup() would previously return a negative error value from
check_leaf(), it now returns 0.
Now fn_trie_lookup() doesn't appear to care about plen, so we can revert
check_leaf() to returning the error value.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Tested-by: William Boughton <bill@boughton.de>
Acked-by: Stephen Heminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kcalloc is supposed to be called with the count as its first argument and
the element size as the second.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reduced version of the spelling cleanup patch.
Take out the confusing language in tcp_frto, and organize the
undocumented values.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix some of the defaults and attempt to clarify some language.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vegard Nossum reported a crash in kmem_cache_alloc():
BUG: unable to handle kernel paging request at da87d000
IP: [<c01991c7>] kmem_cache_alloc+0xc7/0xe0
*pde = 28180163 *pte = 1a87d160
Oops: 0002 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Pid: 3850, comm: grep Not tainted (2.6.26-rc9-00059-gb190333 #5)
EIP: 0060:[<c01991c7>] EFLAGS: 00210203 CPU: 0
EIP is at kmem_cache_alloc+0xc7/0xe0
EAX: 00000000 EBX: da87c100 ECX: 1adad71a EDX: 6b6b6b6b
ESI: 00200282 EDI: da87d000 EBP: f60bfe74 ESP: f60bfe54
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
and analyzed it:
"The register %ecx looks innocent but is very important here. The disassembly:
mov %edx,%ecx
shr $0x2,%ecx
rep stos %eax,%es:(%edi) <-- the fault
So %ecx has been loaded from %edx... which is 0x6b6b6b6b/POISON_FREE.
(0x6b6b6b6b >> 2 == 0x1adadada.)
%ecx is the counter for the memset, from here:
memset(object, 0, c->objsize);
i.e. %ecx was loaded from c->objsize, so "c" must have been freed.
Where did "c" come from? Uh-oh...
c = get_cpu_slab(s, smp_processor_id());
This looks like it has very much to do with CPU hotplug/unplug. Is
there a race between SLUB/hotplug since the CPU slab is used after it
has been freed?"
Good analysis.
Yeah, it's possible that a caller of kmem_cache_alloc() -> slab_alloc()
can be migrated on another CPU right after local_irq_restore() and
before memset(). The inital cpu can become offline in the mean time (or
a migration is a consequence of the CPU going offline) so its
'kmem_cache_cpu' structure gets freed ( slab_cpuup_callback).
At some point of time the caller continues on another CPU having an
obsolete pointer...
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kernel Bugzilla #11063 points out that on some architectures (e.g. x86_32)
exec'ing an ELF without a PT_GNU_STACK program header should default to an
executable stack; but this got broken by the unlimited argv feature because
stack vma is now created before the right personality has been established:
so breaking old binaries using nested function trampolines.
Therefore re-evaluate VM_STACK_FLAGS in setup_arg_pages, where stack
vm_flags used to be set, before the mprotect_fixup. Checking through
our existing VM_flags, none would have changed since insert_vm_struct:
so this seems safer than finding a way through the personality labyrinth.
Reported-by: pageexec@freemail.hu
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gas 2.15 complains about 32-bit registers being used in lea.
AS arch/x86/lib/copy_user_64.o
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_64.S: Assembler messages:
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_64.S:188: Error: `(%edx,%ecx,8)' is not a valid 64 bit base/index expression
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_64.S:257: Error: `(%edx,%ecx,8)' is not a valid 64 bit base/index expression
AS arch/x86/lib/copy_user_nocache_64.o
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_nocache_64.S: Assembler messages:
/local/scratch-2/jeremy/hg/xen/paravirt/linux/arch/x86/lib/copy_user_nocache_64.S:107: Error: `(%edx,%ecx,8)' is not a valid 64 bit base/index expression
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Clean up __migrate_task(): to just have separate "done" and "fail"
cases, instead of that "out" case with random error behavior.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
PREEMPT_RCU without HOTPLUG_CPU is broken. The rcu_online_cpu is called
to initially populate rcu_cpu_online_map with all online CPUs when the
hotplug event handler is installed, and also to populate the map with
CPUs as they come online. The former case is meant to happen with and
without HOTPLUG_CPU, but without HOTPLUG_CPU, the rcu_offline_cpu
function is no-oped -- while it still gets called, it does not set the
rcu CPU map.
With a blank RCU CPU map, grace periods get to tick by completely
oblivious to active RCU read side critical sections. This results in
free-before-grace bugs.
Fix is obvious once the problem is known. (Also, change __devinit to
__cpuinit so the function gets thrown away on !HOTPLUG_CPU kernels).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reported-and-tested-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ Nick is my personal hero of the day - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fix:
arch/x86/pci/built-in.o: In function `pci_subsys_init':
visws.c:(.init.text+0xfc5): undefined reference to `pci_direct_conf1'
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix:
arch/x86/kernel/built-in.o: In function `visws_early_detect':
: undefined reference to `mach_get_smp_config_quirk'
arch/x86/kernel/built-in.o: In function `visws_early_detect':
: undefined reference to `mach_find_smp_config_quirk'
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Integration generated a duplicate call to use_tsc_delay.
Particularly, the one that is done before we check for general
tsc usability seems wrong.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix:
arch/x86/kernel/visws_quirks.c: In function ‘visws_early_detect’:
arch/x86/kernel/visws_quirks.c:293: error: ‘no_broadcast’ undeclared (first use in this function)
arch/x86/kernel/visws_quirks.c:293: error: (Each undeclared identifier is reported only once
arch/x86/kernel/visws_quirks.c:293: error: for each function it appears in.)
make[1]: *** [arch/x86/kernel/visws_quirks.o] Error 1
make: *** [arch/x86/kernel/visws_quirks.o] Error 2
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Patch d49c4288 (tip/x86/mpparse) introduced some changes in calling
subsys_init calls if CONFIG_X86_NUMAQ option is set. This patch
updates subsystem initalization according to this changes.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This is the long awaited ftrace.txt. It explains in quite detail how to
use ftrace and the various tracers.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
