linux-stable.git/arch/s390/kernel/entry64.S, branch linux-3.1.y

[S390] kvm: fix address mode switching

2011-09-20T15:07:34+00:00

598841ca9919d008b520114d8a4378c4ce4e40a1 ([S390] use gmap address
spaces for kvm guest images) changed kvm to use a separate address
space for kvm guests. This address space was switched in __vcpu_run
In some cases (preemption, page fault) there is the possibility that
this address space switch is lost.
The typical symptom was a huge amount of validity intercepts or
random guest addressing exceptions.
Fix this by doing the switch in sie_loop and sie_exit and saving the
address space in the gmap structure itself. Also use the preempt
notifier.

Signed-off-by: Christian Borntraeger 
Acked-by: Avi Kivity 
Signed-off-by: Heiko Carstens

[S390] Add PSW restart shutdown trigger

2011-08-03T14:44:19+00:00

With this patch a new S390 shutdown trigger "restart" is added. If under
z/VM "systerm restart" is entered or under the HMC the "PSW restart" button
is pressed, the PSW located at 0 (31 bit) or 0x1a0 (64 bit) bit is loaded.
Now we execute do_restart() that processes the restart action that is
defined under /sys/firmware/shutdown_actions/on_restart. Currently the
following actions are possible: reipl (default), stop, vmcmd, dump, and
dump_reipl.

Signed-off-by: Michael Holzheu 
Signed-off-by: Heiko Carstens

[S390] fix s390 assembler code alignments

2011-07-24T08:48:21+00:00

The alignment is missing for various global symbols in s390 assembly code.
With a recent gcc and an instruction like stgrl this can lead to a
specification exception if the instruction uses such a mis-aligned address.

Specify the alignment explicitely and while add it define __ALIGN for s390
and use the ENTRY define to save some lines of code.

Signed-off-by: Jan Glauber 
Signed-off-by: Martin Schwidefsky

[S390] move sie code to entry.S

2011-07-24T08:48:21+00:00

The entry to / exit from sie has subtle dependencies to the first level
interrupt handler. Move the sie assembler code to entry64.S and replace
the SIE_HOOK callback with a test and the new _TIF_SIE bit.
In addition this patch fixes several problems in regard to the check for
the_TIF_EXIT_SIE bits. The old code checked the TIF bits before executing
the interrupt handler and it only modified the instruction address if it
pointed directly to the sie instruction. In both cases it could miss
a TIF bit that normally would cause an exit from the guest and would
reenter the guest context.

Signed-off-by: Martin Schwidefsky

[S390] pfault: cpu hotplug vs missing completion interrupts

2011-05-23T08:24:29+00:00

On cpu hot remove a PFAULT CANCEL command is sent to the hypervisor
which in turn will cancel all outstanding pfault requests that have
been issued on that cpu (the same happens with a SIGP cpu reset).

The result is that we end up with uninterruptible processes where
the interrupt that would wake up these processes never arrives.

In order to solve this all processes which wait for a pfault
completion interrupt get woken up after a cpu hot remove. The worst
case that could happen is that they fault again and in turn need to
wait again.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

[S390] kernel: Initialize register 14 when starting new CPU

2011-05-10T15:13:42+00:00

When starting a new CPU we currently jump to start_secondary() without
setting register 14 (the return address) correctly. Therefore on the stack
frame for start_secondary an invalid return address is stored. This leads
to wrong stack back traces in kernel dumps.

Example:

 #00 [1f33fe48] cpu_idle at 10614a
 #01 [1f33fe90] start_secondary at 54fa88
 #02 [1f33feb8] (null) at 0                 <--- invalid

To fix this start_secondary() is called now with basr/brasl that sets
register 14 correctly. The output of the stack backtrace looks then
like the following:

 #00 [1f33fe48] cpu_idle at 10614a
 #01 [1f33fe90] start_secondary at 54fa88
 #02 [1f33feb8] restart_base at 54f41e      <--- correct

Signed-off-by: Michael Holzheu 
Signed-off-by: Martin Schwidefsky

[S390] ptrace cleanup

2011-01-05T11:47:31+00:00

Overhaul program event recording and the code dealing with the ptrace
user space interface.

Signed-off-by: Martin Schwidefsky

[S390] add kprobes annotations

2011-01-05T11:47:24+00:00

Add kprobes annotations to get the massive 'probe kernel.function("*") {}'
stress test working.

Signed-off-by: Martin Schwidefsky

[S390] fix kprobes single stepping

2010-10-29T14:50:50+00:00

Fix kprobes after git commit 1e54622e0403891b10f2105663e0f9dd595a1f17
broke it. The kprobe_handler is now called with interrupts in the state
at the time of the breakpoint. The single step of the replaced instruction
is done with interrupts off which makes it necessary to enable and disable
the interupts in the kprobes code.

Signed-off-by: Martin Schwidefsky

[S390] cleanup system call parameter setup

2010-10-25T14:10:19+00:00

Do the setup of the stack overflow argument for the sixth system
call parameter right before the branch to the system call function.
That simplifies the system call parameter access code.

Signed-off-by: Martin Schwidefsky