linux-stable.git/arch, branch v3.15.4

ptrace,x86: force IRET path after a ptrace_stop()

2014-07-07T01:59:12+00:00

commit b9cd18de4db3c9ffa7e17b0dc0ca99ed5aa4d43a upstream.

The 'sysret' fastpath does not correctly restore even all regular
registers, much less any segment registers or reflags values.  That is
very much part of why it's faster than 'iret'.

Normally that isn't a problem, because the normal ptrace() interface
catches the process using the signal handler infrastructure, which
always returns with an iret.

However, some paths can get caught using ptrace_event() instead of the
signal path, and for those we need to make sure that we aren't going to
return to user space using 'sysret'.  Otherwise the modifications that
may have been done to the register set by the tracer wouldn't
necessarily take effect.

Fix it by forcing IRET path by setting TIF_NOTIFY_RESUME from
arch_ptrace_stop_needed() which is invoked from ptrace_stop().

Signed-off-by: Tejun Heo 
Reported-by: Andy Lutomirski 
Acked-by: Oleg Nesterov 
Suggested-by: Linus Torvalds 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

MIPS: KVM: Fix memory leak on VCPU

2014-07-07T01:59:12+00:00

commit 8c9eb041cf76038eb3b62ee259607eec9b89f48d upstream.

kvm_arch_vcpu_free() is called in 2 code paths:

1) kvm_vm_ioctl()
       kvm_vm_ioctl_create_vcpu()
           kvm_arch_vcpu_destroy()
               kvm_arch_vcpu_free()
2) kvm_put_kvm()
       kvm_destroy_vm()
           kvm_arch_destroy_vm()
               kvm_mips_free_vcpus()
                   kvm_arch_vcpu_free()

Neither of the paths handles VCPU free. We need to do it in
kvm_arch_vcpu_free() corresponding to the memory allocation in
kvm_arch_vcpu_create().

Signed-off-by: Deng-Cheng Zhu 
Reviewed-by: James Hogan 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

MIPS: KVM: Remove redundant NULL checks before kfree()

2014-07-07T01:59:12+00:00

commit c6c0a6637f9da54f9472144d44f71cf847f92e20 upstream.

The kfree() function already NULL checks the parameter so remove the
redundant NULL checks before kfree() calls in arch/mips/kvm/.

Signed-off-by: James Hogan 
Cc: Paolo Bonzini 
Cc: Gleb Natapov 
Cc: kvm@vger.kernel.org
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc: Sanjay Lal 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

powerpc: Don't skip ePAPR spin-table CPUs

2014-07-07T01:59:11+00:00

commit 6663a4fa6711050036562ddfd2086edf735fae21 upstream.

Commit 59a53afe70fd530040bdc69581f03d880157f15a "powerpc: Don't setup
CPUs with bad status" broke ePAPR SMP booting.  ePAPR says that CPUs
that aren't presently running shall have status of disabled, with
enable-method being used to determine whether the CPU can be enabled.

Fix by checking for spin-table, which is currently the only supported
enable-method.

Signed-off-by: Scott Wood 
Cc: Michael Neuling 
Cc: Emil Medve 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: Add AT_HWCAP2 to indicate V.CRYPTO category support

2014-07-07T01:59:11+00:00

commit dd58a092c4202f2bd490adab7285b3ff77f8e467 upstream.

The Vector Crypto category instructions are supported by current POWER8
chips, advertise them to userspace using a specific bit to properly
differentiate with chips of the same architecture level that might not
have them.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: Don't setup CPUs with bad status

2014-07-07T01:59:11+00:00

commit 59a53afe70fd530040bdc69581f03d880157f15a upstream.

OPAL will mark a CPU that is guarded as "bad" in the status property of the CPU
node.

Unfortunatley Linux doesn't check this property and will put the bad CPU in the
present map.  This has caused hangs on booting when we try to unsplit the core.

This patch checks the CPU is avaliable via this status property before putting
it in the present map.

Signed-off-by: Michael Neuling 
Tested-by: Anton Blanchard 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: fix typo 'CONFIG_PPC_CPU'

2014-07-07T01:59:11+00:00

commit b69a1da94f3d1589d1942b5d1b384d8cfaac4500 upstream.

Commit cd64d1697cf0 ("powerpc: mtmsrd not defined") added a check for
CONFIG_PPC_CPU were a check for CONFIG_PPC_FPU was clearly intended.

Fixes: cd64d1697cf0 ("powerpc: mtmsrd not defined")
Signed-off-by: Paul Bolle 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc/perf: Ensure all EBB register state is cleared on fork()

2014-07-07T01:59:11+00:00

commit 3df48c981d5a9610e02e9270b1bc4274fb536710 upstream.

In commit 330a1eb "Core EBB support for 64-bit book3s" I messed up
clear_task_ebb(). It clears some but not all of the task's Event Based
Branch (EBB) registers when we duplicate a task struct.

That allows a child task to observe the EBBHR & EBBRR of its parent,
which it should not be able to do.

Fix it by clearing EBBHR & EBBRR.

Signed-off-by: Michael Ellerman 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: fix typo 'CONFIG_PMAC'

2014-07-07T01:59:11+00:00

commit 6e0fdf9af216887e0032c19d276889aad41cad00 upstream.

Commit b0d278b7d3ae ("powerpc/perf_event: Reduce latency of calling
perf_event_do_pending") added a check for CONFIG_PMAC were a check for
CONFIG_PPC_PMAC was clearly intended.

Fixes: b0d278b7d3ae ("powerpc/perf_event: Reduce latency of calling perf_event_do_pending")
Signed-off-by: Paul Bolle 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: 64bit sendfile is capped at 2GB

2014-07-07T01:59:11+00:00

commit 5d73320a96fcce80286f1447864c481b5f0b96fa upstream.

commit 8f9c0119d7ba (compat: fs: Generic compat_sys_sendfile
implementation) changed the PowerPC 64bit sendfile call from
sys_sendile64 to sys_sendfile.

Unfortunately this broke sendfile of lengths greater than 2G because
sys_sendfile caps at MAX_NON_LFS. Restore what we had previously which
fixes the bug.

Signed-off-by: Anton Blanchard 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman