linux.git/arch/s390/kernel, branch v4.4.12

s390/cpumf: add missing lpp magic initialization

2016-04-12T16:08:36+00:00

commit 8f100bb1ff27873dd71f636da670e503b9ade3c6 upstream.

Add the missing lpp magic initialization for cpu 0. Without this all
samples on cpu 0 do not have the most significant bit set in the
program parameter field, which we use to distinguish between guest and
host samples if the pid is also 0.

We did initialize the lpp magic in the absolute zero lowcore but
forgot that when switching to the allocated lowcore on cpu 0 only.

Reported-by: Shu Juan Zhang 
Acked-by: Christian Borntraeger 
Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390: fix floating pointer register corruption (again)

2016-04-12T16:08:36+00:00

commit e370e4769463a65dcf8806fa26d2874e0542ac41 upstream.

There is a tricky interaction between the machine check handler
and the critical sections of load_fpu_regs and save_fpu_regs
functions. If the machine check interrupts one of the two
functions the critical section cleanup will complete the function
before the machine check handler s390_do_machine_check is called.
Trouble is that the machine check handler needs to validate the
floating point registers *before* and not *after* the completion
of load_fpu_regs/save_fpu_regs.

The simplest solution is to rewind the PSW to the start of the
load_fpu_regs/save_fpu_regs and retry the function after the
return from the machine check handler.

Tested-by: Christian Borntraeger 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/cpumf: Fix lpp detection

2016-04-12T16:08:31+00:00

commit 7a76aa95f6f6682db5629449d763251d1c9f8c4e upstream.

we have to check bit 40 of the facility list before issuing LPP
and not bit 48. Otherwise a guest running on a system with
"The decimal-floating-point zoned-conversion facility" and without
the "The set-program-parameters facility" might crash on an lpp
instruction.

Signed-off-by: Christian Borntraeger 
Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/compat: correct restore of high gprs on signal return

2016-03-03T23:07:12+00:00

commit 342300cc9cd3428bc6bfe5809bfcc1b9a0f06702 upstream.

git commit 8070361799ae1e3f4ef347bd10f0a508ac10acfb
"s390: add support for vector extension"
broke 31-bit compat processes in regard to signal handling.

The restore_sigregs_ext32() function is used to restore the additional
elements from the user space signal frame. Among the additional elements
are the upper registers halves for 64-bit register support for 31-bit
processes. The copy_from_user that is used to retrieve the high-gprs
array from the user stack uses an incorrect length, 8 bytes instead of
64 bytes. This causes incorrect upper register halves to get loaded.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/kvm: remove dependency on struct save_area definition

2016-03-03T23:07:11+00:00

commit d9a3a09af54d01ab8b0c320580f4f95328d4a7ac upstream.

Replace the offsets based on the struct area_area with the offset
constants from asm-offsets.c based on the struct _lowcore.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/dis: Fix handling of format specifiers

2015-12-18T13:43:21+00:00

The print_insn() function returns strings like "lghi %r1,0". To escape the
'%' character in sprintf() a second '%' is used. For example "lghi %%r1,0"
is converted into "lghi %r1,0".

After print_insn() the output string is passed to printk(). Because format
specifiers like "%r" or "%f" are ignored by printk() this works by chance
most of the time. But for instructions with control registers like
"lctl %c6,%c6,780" this fails because printk() interprets "%c" as
character format specifier.

Fix this problem and escape the '%' characters twice.

For example "lctl %%%%c6,%%%%c6,780" is then converted by sprintf()
into "lctl %%c6,%%c6,780" and by printk() into "lctl %c6,%c6,780".

Signed-off-by: Michael Holzheu 
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky

s390: remove SALIPL loader

2015-11-16T11:51:11+00:00

There is no known user, therefore remove the code.

Acked-by: Rob Van Der Heij 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390: wire up mlock2 system call

2015-11-16T11:51:07+00:00

Passes mlock2-tests test case in 64 bit and compat mode.

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

s390: remove g5 elf platform support

2015-11-16T11:04:41+00:00

Remove dead code, since this could only happen on a 31 bit machine
where the kernel wouldn't IPL.

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

s390: avoid cache aliasing under z/VM and KVM

2015-11-16T11:04:18+00:00

commit 1f6b83e5e4d3 ("s390: avoid z13 cache aliasing") checks for the
machine type to optimize address space randomization and zero page
allocation to avoid cache aliases.

This check might fail under a hypervisor with migration support.
z/VMs "Single System Image and Live Guest Relocation" facility will
"fake" the machine type of the oldest system in the group. For example
in a group of zEC12 and Z13 the guest appears to run on a zEC12
(architecture fencing within the relocation domain)

Remove the machine type detection and always use cache aliasing
rules that are known to work for all machines. These are the z13
aliasing rules.

Suggested-by: Christian Borntraeger 
Reviewed-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky