The "cleanup console_print()" patch in commit
353f6dd2de introduced an "extern"
declaration into an assembly language file. Remove it.
Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sysbench thinks SD_BALANCE_WAKE is too agressive and kbuild doesn't
really mind too much, SD_BALANCE_NEWIDLE picks up most of the
slack.
On a dual socket, quad core, dual thread nehalem system:
sysbench (--num_threads=16):
SD_BALANCE_WAKE-: 13982 tx/s
SD_BALANCE_WAKE+: 15688 tx/s
kbuild (-j16):
SD_BALANCE_WAKE-: 47.648295846 seconds time elapsed ( +- 0.312% )
SD_BALANCE_WAKE+: 47.608607360 seconds time elapsed ( +- 0.026% )
(same within noise)
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Aside from using fewer output sections and moving some data around,
the main side effect of this change is changing the alignment of some
sections. In particular:
* cachline-aligned and read_mostly data are now aligned to
SMP_CACHE_BYTES. (Previously, they were laid out consecutively after
a PAGE_SIZE alignment)
* .init.ramfs is now page-aligned, per the INIT_RAM_FS
macro. (Previously it had no explicit alignment).
Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
It seems that start_ap doesn't need to be in a special location in the
kernel, but it references some init code so it should be in .ref.text.
Since this is the only thing in the .text.head section, eliminate
.text.head from the linker script.
Signed-off-by: Tim Abbott <tabbott@ksplice.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
When
* there is almost out of ates
* one asks for more than one ate
* there are some available at the end of ate array
then the inner for loop will end without incrementing 'index'. This
means the outer loop will start at the same point finding it's available
and runs the inner loop again from the same index. This repeats forever.
Hence make sure we check we were at the end of ate array and return
an error in such case.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Found-by: Jeff Mahoney <jeffm@novell.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
If we're looking to place a new task, we might as well find the
idlest position _now_, not 1 tick ago.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make the idle balancer more agressive, to improve a
x264 encoding workload provided by Jason Garrett-Glaser:
NEXT_BUDDY NO_LB_BIAS
encoded 600 frames, 252.82 fps, 22096.60 kb/s
encoded 600 frames, 250.69 fps, 22096.60 kb/s
encoded 600 frames, 245.76 fps, 22096.60 kb/s
NO_NEXT_BUDDY LB_BIAS
encoded 600 frames, 344.44 fps, 22096.60 kb/s
encoded 600 frames, 346.66 fps, 22096.60 kb/s
encoded 600 frames, 352.59 fps, 22096.60 kb/s
NO_NEXT_BUDDY NO_LB_BIAS
encoded 600 frames, 425.75 fps, 22096.60 kb/s
encoded 600 frames, 425.45 fps, 22096.60 kb/s
encoded 600 frames, 422.49 fps, 22096.60 kb/s
Peter pointed out that this is better done via newidle_idx,
not via LB_BIAS, newidle balancing should look for where
there is load _now_, not where there was load 2 ticks ago.
Worst-case latencies are improved as well as no buddies
means less vruntime spread. (as per prior lkml discussions)
This change improves kbuild-peak parallelism as well.
Reported-by: Jason Garrett-Glaser <darkshikari@gmail.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1253011667.9128.16.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When merging select_task_rq_fair() and sched_balance_self() we lost
the use of wake_idx, restore that and set them to 0 to make wake
balancing more aggressive.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The problem with wake_idle() is that is doesn't respect things like
cpu_power, which means it doesn't deal well with SMT nor the recent
RT interaction.
To cure this, it needs to do what sched_balance_self() does, which
leads to the possibility of merging select_task_rq_fair() and
sched_balance_self().
Modify sched_balance_self() to:
- update_shares() when walking up the domain tree,
(it only called it for the top domain, but it should
have done this anyway), which allows us to remove
this ugly bit from try_to_wake_up().
- do wake_affine() on the smallest domain that contains
both this (the waking) and the prev (the wakee) cpu for
WAKE invocations.
Then use the top-down balance steps it had to replace wake_idle().
This leads to the dissapearance of SD_WAKE_BALANCE and
SD_WAKE_IDLE_FAR, with SD_WAKE_IDLE replaced with SD_BALANCE_WAKE.
SD_WAKE_AFFINE needs SD_BALANCE_WAKE to be effective.
Touch all topology bits to replace the old with new SD flags --
platforms might need re-tuning, enabling SD_BALANCE_WAKE
conditionally on a NUMA distance seems like a good additional
feature, magny-core and small nehalem systems would want this
enabled, systems with slow interconnects would not.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
console_print() is an old legacy interface mostly unused in the entire
kernel tree. It's best to clean up its existing use and let developers
use their own implementation of it as they feel fit.
Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Setting monarch_cpu = -1 to let slaves frozen might not work, because
there might be slaves being late, not entered the rendezvous yet.
Such slaves might be caught in while (monarch_cpu == -1) loop.
Use kdump_in_progress instead of monarch_cpus to break INIT rendezvous
and let all slaves enter DIE_INIT_SLAVE_LEAVE smoothly.
And monarch no longer need to manage rendezvous if once kdump_in_progress
is set, catch the monarch in DIE_INIT_MONARCH_ENTER then.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
kdump_on_init
CPUs should be frozen if possible, otherwise it might hinder kdump.
So if there are CPUs not respond to IPI, try INIT to stop them.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Summary:
Asserting INIT might block kdump if the system is already going to
start kdump via panic.
Description:
INIT can interrupt anywhere in panic path, so it can interrupt in
middle of kdump kicked by panic. Therefore there is a race if kdump
is kicked concurrently, via Panic and via INIT.
INIT could fail to invoke kdump if the system is already going to
start kdump via panic. It could not restart kdump from INIT handler
if some of cpus are already playing dead with INIT masked. It also
means that INIT could block kdump's progress if no monarch is entered
in the INIT rendezvous.
Panic+INIT is a rare, but possible situation since it can be assumed
that the kernel or an internal agent decides to panic the unstable
system while another external agent decides to send an INIT to the
system at same time.
How to reproduce:
Assert INIT just after panic, before all other cpus have frozen
Expected results:
continue kdump invoked by panic, or restart kdump from INIT
Actual results:
might be hang, crashdump not retrieved
Proposed Fix:
This patch masks INIT first in panic path to take the initiative on
kdump, and reuse atomic value kdump_in_progress to make sure there is
only one initiator of kdump. All INITs asserted later should be used
only for freezing all other cpus.
This mask will be removed soon by rfi in relocate_kernel.S, before jump
into kdump kernel, after all cpus are frozen and no-op INIT handler is
registered. So if INIT was in the interval while it is masked, it will
pend on the system and will received just after the rfi, and handled by
the no-op handler.
If there was a MCA event while psr.mc is 1, in theory the event will
pend on the system and will received just after the rfi same as above.
MCA handler is unregistered here at the time, so received MCA will not
reach to OS_MCA and will result in warmboot by SAL.
Note that codes in this masked interval are relatively simpler than
that in MCA/INIT handler which also executed with the mask. So it can
be said that probability of error in this interval is supposed not so
higher than that in MCA/INIT handler.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Summary:
Asserting INIT on cpu going to be offline will result in unexpected
behavior. It will be a real problem in kdump cases where INIT might
be asserted to unstable APs going to be offline by returning to SAL.
Description:
Since psr.mc is cleared when bits in psr are set to SAL_PSR_BITS_TO_SET
in ia64_jump_to_sal(), there is a small window (~few msecs) that the
cpu can receive INIT even if the cpu enter there via INIT handler.
In this window we do restore of registers for SAL, so INIT asserted
here will not work properly.
It is hard to remove this window by masking INIT (i.e. setting psr.mc)
because we have to unmask it later in OS, because we have to use branch
instruction (br.ret, not rfi) to return SAL, due to OS_BOOT_RENDEZ to
SAL return convention.
I suppose this window will not be a real problem on cpu offline if we
can educate people not to push INIT button during hotplug operation.
However, only exception is a race in kdump and INIT. Now kdump returns
APs to SAL before processing dump, but the kernel might receive INIT at
that point in time. Such INIT might be asserted by kdump itself if an
AP doesn't react IPI soon and kdump decided to use INIT to stop the AP.
Or it might be asserted by operator or an external agent to start dump
on the unstable system.
Such panic+INIT or INIT+INIT cases should be rare, but it will be happy
if we can retrieve crashdump even in such cases.
How to reproduce:
panic+INIT or INIT+INIT, with kdump configured
Expected results:
crashdump is retrieved anyway
Actual results:
panic, hang etc. (unexpected)
Proposed fix
To avoid the window on the way to SAL, this patch stops returning APs
to SAL in case of kdump. In other words, this patch makes APs spin
in OS instead of spinning in SAL.
(* Note: What impact would be there? If a cpu is spinning in SAL,
the cpu is in BOOT_RENDEZ loop, as same as offlined cpu.
In theory if an INIT is asserted there, cpus in the BOOT_RENDEZ loop
should not invoke OS_INIT on it. So in either way, no matter where
the cpu is spinning actually in, once cpu starts spin and act as
"frozen," INIT on the cpu have no effects.
From another point of view, all debug information on the cpu should
have stored to memory before the cpu start to be frozen. So no more
action on the cpu is required.)
I confirmed that the kdump sometime hangs by concurrent INITs (another
INIT after an INIT), and it doesn't hang after applying this patch.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Summary:
MCA on the beginning of kdump/kexec kernel will result in unexpected
behavior because MCA handler for previous kernel is invoked on the
kdump kernel.
Description:
Once a cpu is passed to new kernel, all resources in previous kernel
should not be used from the cpu. Even the resources for MCA handler
are no exception. So we cannot handle MCAs and its machine check
errors during kernel transition, until new handler for new kernel is
registered with new resources ready for handling the MCA.
How to reproduce:
Assert MCA while kdump kernel is booting, before new MCA handler for
kdump kernel is registered.
Expected(Desirable) results:
No recovery, cancel kdump and reboot the system.
Actual results:
MCA handler for previous kernel is invoked on the kdump kernel.
=> panic, hang etc. (unexpected)
Proposed fix:
To avoid entering MCA handler from early stage of new kernel,
unregister the entry point from SAL before leave from current
kernel. Then SAL will make all MCAs to warmboot safely, without
invoking OS_MCA.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
kdump/kexec kernel
Summary:
Asserting INIT on the beginning of kdump/kexec kernel will result
in unexpected behavior because INIT handler for previous kernel is
invoked on new kernel.
Description:
In panic situation, we can receive INIT while kernel transition,
i.e. from beginning of panic to bootstrap of kdump kernel.
Since we initialize registers on leave from current kernel, no
longer monarch/slave handlers of current kernel in virtual mode are
called safely. (In fact system goes hang as far as I confirmed)
How to Reproduce:
Start kdump
# echo c > /proc/sysrq-trigger
Then assert INIT while kdump kernel is booting, before new INIT
handler for kdump kernel is registered.
Expected(Desirable) result:
kdump kernel boots without any problem, crashdump retrieved
Actual result:
INIT handler for previous kernel is invoked on kdump kernel
=> panic, hang etc. (unexpected)
Proposed fix:
We can unregister these init handlers from SAL before jumping into
new kernel, however then the INIT will fallback to default behavior,
result in warmboot by SAL (according to the SAL specification) and
we cannot retrieve the crashdump.
Therefore this patch introduces a NOP init handler and register it
to SAL before leave from current kernel, to start kdump safely by
preventing INITs from entering virtual mode and resulting in warmboot.
On the other hand, in case of kexec that not for kdump, it also
has same problem with INIT while kernel transition.
This patch handles this case differently, because for kexec
unregistering handlers will be preferred than registering NOP
handler, since the situation "no handlers registered" is usual
state for kernel's entry.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Summary:
INIT asserted on kdump kernel invokes INIT handler not only on a
cpu that running on the kdump kernel, but also BSP of the panicked
kernel, because the (badly) frozen BSP can be thawed by INIT.
Description:
The kdump_cpu_freeze() is called on cpus except one that initiates
panic and/or kdump, to stop/offline the cpu (on ia64, it means we
pass control of cpus to SAL, or put them in spinloop). Note that
CPU0(BSP) always go to spinloop, so if panic was happened on an AP,
there are at least 2cpus (= the AP and BSP) which not back to SAL.
On the spinning cpus, interrupts are disabled (rsm psr.i), but INIT
is still interruptible because psr.mc for mask them is not set unless
kdump_cpu_freeze() is not called from MCA/INIT context.
Therefore, assume that a panic was happened on an AP, kdump was
invoked, new INIT handlers for kdump kernel was registered and then
an INIT is asserted. From the viewpoint of SAL, there are 2 online
cpus, so INIT will be delivered to both of them. It likely means
that not only the AP (= a cpu executing kdump) enters INIT handler
which is newly registered, but also BSP (= another cpu spinning in
panicked kernel) enters the same INIT handler. Of course setting of
registers in BSP are still old (for panicked kernel), so what happen
with running handler with wrong setting will be extremely unexpected.
I believe this is not desirable behavior.
How to Reproduce:
Start kdump on one of APs (e.g. cpu1)
# taskset 0x2 echo c > /proc/sysrq-trigger
Then assert INIT after kdump kernel is booted, after new INIT handler
for kdump kernel is registered.
Expected results:
An INIT handler is invoked only on the AP.
Actual results:
An INIT handler is invoked on the AP and BSP.
Sample of results:
I got following console log by asserting INIT after prompt "root:/>".
It seems that two monarchs appeared by one INIT, and one panicked at
last. And it also seems that the panicked one supposed there were
4 online cpus and no one did rendezvous:
:
[ 0 %]dropping to initramfs shell
exiting this shell will reboot your system
root:/> Entered OS INIT handler. PSP=fff301a0 cpu=0 monarch=0
ia64_init_handler: Promoting cpu 0 to monarch.
Delaying for 5 seconds...
All OS INIT slaves have reached rendezvous
Processes interrupted by INIT - 0 (cpu 0 task 0xa000000100af0000)
:
<<snip>>
:
Entered OS INIT handler. PSP=fff301a0 cpu=0 monarch=1
Delaying for 5 seconds...
mlogbuf_finish: printing switched to urgent mode, MCA/INIT might be dodgy or fail.
OS INIT slave did not rendezvous on cpu 1 2 3
INIT swapper 0[0]: bugcheck! 0 [1]
:
<<snip>>
:
Kernel panic - not syncing: Attempted to kill the idle task!
Proposed fix:
To avoid this problem, this patch inserts ia64_set_psr_mc() to mask
INIT on cpus going to be frozen. This masking have no effect if the
kdump_cpu_freeze() is called from INIT handler when kdump_on_init == 1,
because psr.mc is already turned on to 1 before entering OS_INIT.
I confirmed that weird log like above are disappeared after applying
this patch.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: kexec@lists.infradead.org
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from
interface between general code and arch code. kvm_arch_vcpu_runnable()
checks for interrupts instead.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write
functions. in_range now becomes unused so it is removed from device ops in
favor of read/write callbacks performing range checks internally.
This allows aliasing (mostly for in-kernel virtio), as well as better error
handling by making it possible to pass errors up to userspace.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Archs are free to use vcpu_id as they see fit. For x86 it is used as
vcpu's apic id. New ioctl is added to configure boot vcpu id that was
assumed to be 0 till now.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:
CPU A CPU B
kvm_vm_ioctl_deassign_dev_irq()
mutex_lock(&kvm->lock); worker_thread()
-> kvm_deassign_irq() -> kvm_assigned_dev_interrupt_work_handler()
-> deassign_host_irq() mutex_lock(&kvm->lock);
-> cancel_work_sync() [blocked]
[gleb: fix ia64 path]
Reported-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Init the itc_offset for all possible vCPUs. The current code by
mistake ends up only initializing the offset on vCPU 0.
Spotted by Gleb Natapov.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by : Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This was #define'd as 0 on all platforms, so let's get rid of it.
This change makes pci_scan_slot() slightly easier to read.
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The 32-bit parameters (len and csum) of csum_ipv6_magic() are passed in 64-bit
registers in2 and in4. The high order 32 bits of the registers were never
cleared, and garbage was sometimes calculated into the checksum.
Fix this by clearing the high order 32 bits of these registers.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Tony Luck <tony.luck@intel.com>
arch/ia64/kernel/dma-mapping.c:14: warning: control reaches end of non-void function
arch/ia64/kernel/dma-mapping.c:14: warning: no return statement in function returning non-void
This warning was introduced by commit: 390bd132b2
Add dma_debug_init() for ia64
Signed-off-by: Tony Luck <tony.luck@intel.com>
Add a keyctl to install a process's session keyring onto its parent. This
replaces the parent's session keyring. Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again. Normally this
will be after a wait*() syscall.
To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.
The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.
Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the
replacement to be performed at the point the parent process resumes userspace
execution.
This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership. However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.
This can be tested with the following program:
#include <stdio.h>
#include <stdlib.h>
#include <keyutils.h>
#define KEYCTL_SESSION_TO_PARENT 18
#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
int main(int argc, char **argv)
{
key_serial_t keyring, key;
long ret;
keyring = keyctl_join_session_keyring(argv[1]);
OSERROR(keyring, "keyctl_join_session_keyring");
key = add_key("user", "a", "b", 1, keyring);
OSERROR(key, "add_key");
ret = keyctl(KEYCTL_SESSION_TO_PARENT);
OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
return 0;
}
Compiled and linked with -lkeyutils, you should see something like:
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
355907932 --alswrv 4043 -1 \_ keyring: _uid.4043
[dhowells@andromeda ~]$ /tmp/newpag
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
1055658746 --alswrv 4043 4043 \_ user: a
[dhowells@andromeda ~]$ /tmp/newpag hello
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: hello
340417692 --alswrv 4043 4043 \_ user: a
Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Only IA64 was using PG_uncached as of now. We now intend to use this bit
in x86 as well, to keep track of memory type of those addresses that
have page struct for them. So, generalize the use of that bit across
ia64 and x86.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Between GCC version 3.4.0 and 4.3.3 (including 3.4.0 and 4.3.3), -mtune=merced
is implemented in GCC. Starting from 4.4.0, -mtune=merced is deprecated.
Even implemented in versions between 3.4.0 and 4.3.3, the -mtune=merced
feature has been broken in some of the versions. For example, GCC 4.1.2 reports
interanl tuning function errors during kernel building with -mtune=merced. Or
GCC Bugzilla 16130 reports another -mtune=merced issue on GCC 3.4.1.
So I would remove the -mtune=merced from IA64 kernel build. Without this option,
kernel on Merced will remain the same except losing an unstable and out-of-date
performance tunning feature.
Since GCC version 3.4.0, -mtune=mckinley has been implemented. The
-mtune=mckinley option functions the same as mtune=itanium2. And mtune=itanium2
is the default option. So we don't need to add mtune=mckinley either since its
been the default option in any GCC version which implements this option.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/include/asm/pgtable.h: asm/processor.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/kernel/ia64_ksyms.c: asm/page.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
__test_and_clear_bit() returns a bitfield with the tested-for bit set.
Make it consistent with the other bitops - of ia64 but also every
other architecture - and return a boolean value.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
In commit 160c1d8e40,
dma_ops->dma_supported = iommu_dma_supported;
This dma_ops->dma_supported is first called in platform_dma_init() during kernel
boot. Then dma_ops->dma_supported will be called recursively in
iommu_dma_supported.
Kernel can not boot because kernel can not get out of iommu_dma_supported until
it runs out of stack memory.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
flush_write_buffers() in dma-mapping-common.h was removed so we
can remove NULL flush_write_buffers() in IA64.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: davem@davemloft.net
LKML-Reference: <1249872797-1314-3-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This sockopt goes in line with SO_TYPE and SO_PROTOCOL. It makes it
possible for userspace programs to pass around file descriptors — I
am referring to arguments-to-functions, but it may even work for the
fd passing over UNIX sockets — without needing to also pass the
auxiliary information (PF_INET6/IPPROTO_TCP).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to SO_TYPE returning the socket type, SO_PROTOCOL allows to
retrieve the protocol used with a given socket.
I am not quite sure why we have that-many copies of socket.h, and why
the values are not the same on all arches either, but for where hex
numbers dominate, I use 0x1029 for SO_PROTOCOL as that seems to be
the next free unused number across a bunch of operating systems, or
so Google results make me want to believe. SO_PROTOCOL for others
just uses the next free Linux number, 38.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds two functions, phys_to_dma() and dma_to_phys() to x86, IA64
and powerpc. swiotlb uses them. phys_to_dma() converts a physical
address to a dma address. dma_to_phys() does the opposite.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
dma_capable() eventually replaces is_buffer_dma_capable(), which tells
if a memory area is dma-capable or not. The problem of
is_buffer_dma_capable() is that it doesn't take a pointer to struct
device so it doesn't work for POWERPC.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Anand Gadiyar