linux-toradex.git/arch/powerpc/kernel/kvm_emul.S, branch v6.16

powerpc/kvm: Add ifdefs around template code

2019-09-13T14:04:40+00:00

Some of the templates used for KVM patching are only used on certain
platforms, but currently they are always built-in, fix that.

Signed-off-by: Michael Ellerman 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190911115746.12433-4-mpe@ellerman.id.au

powerpc/kvm: Move kvm_tmp into .text, shrink to 64K

2019-09-13T14:04:40+00:00

In some configurations of KVM, guests binary patch themselves to
avoid/reduce trapping into the hypervisor. For some instructions this
requires replacing one instruction with a sequence of instructions.

For those cases we need to write the sequence of instructions
somewhere and then patch the location of the original instruction to
branch to the sequence. That requires that the location of the
sequence be within 32MB of the original instruction.

The current solution for this is that we create a 1MB array in BSS,
write sequences into there, and then free the remainder of the array.

This has a few problems:
 - it confuses kmemleak.
 - it confuses lockdep.
 - it requires mapping kvm_tmp executable, which can cause adjacent
   areas to also be mapped executable if we're using 16M pages for the
   linear mapping.
 - the 32MB limit can be exceeded if the kernel is big enough,
   especially with STRICT_KERNEL_RWX enabled, which then prevents the
   patching from working at all.

We can fix all those problems by making kvm_tmp just a region of
regular .text. However currently it's 1MB in size, and we don't want
to waste 1MB of text. In practice however I only see ~30KB of kvm_tmp
being used even for an allyes_config. So shrink kvm_tmp to 64K, which
ought to be enough for everyone, and move it into .text.

Signed-off-by: Michael Ellerman 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190911115746.12433-1-mpe@ellerman.id.au

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266

2019-06-05T15:30:28+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation 51 franklin street fifth floor boston ma 02110
  1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 67 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Richard Fontana 
Reviewed-by: Alexios Zavras 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141333.953658117@linutronix.de
Signed-off-by: Greg Kroah-Hartman

powerpc: move ASM_CONST and stringify_in_c() into asm-const.h

2018-07-30T12:48:16+00:00

This patch moves ASM_CONST() and stringify_in_c() into
dedicated asm-const.h, then cleans all related inclusions.

Signed-off-by: Christophe Leroy 
[mpe: asm-compat.h should include asm-const.h]
Signed-off-by: Michael Ellerman

KVM: PPC: Not optimizing MSR_CE and MSR_ME with paravirt.

2012-05-30T09:43:11+00:00

If there is pending critical or machine check interrupt then guest
would like to capture it when guest enable MSR.CE and MSR_ME respectively.
Also as mostly MSR_CE and MSR_ME are updated with rfi/rfci/rfmii
which anyway traps so removing the the paravirt optimization for MSR.CE
and MSR.ME.

Signed-off-by: Bharat Bhushan 
Signed-off-by: Alexander Graf

KVM: PPC: Factor out guest epapr initialization

2012-05-30T09:43:10+00:00

epapr paravirtualization support is now a Kconfig
selectable option

Signed-off-by: Liu Yu 
[stuart.yoder@freescale.com: misc minor fixes, description update]
Signed-off-by: Stuart Yoder 
Signed-off-by: Alexander Graf

KVM: PPC: Avoid patching paravirt template code

2012-03-05T12:52:34+00:00

Currently we patch the whole code include paravirt template code.
This isn't safe for scratch area and has impact to performance.

Signed-off-by: Liu Yu 
Signed-off-by: Alexander Graf 
Signed-off-by: Avi Kivity

KVM: PPC: booke: Paravirtualize wrtee

2012-03-05T12:52:26+00:00

Also fix wrteei 1 paravirt to check for a pending interrupt.

Signed-off-by: Scott Wood 
Signed-off-by: Alexander Graf 
Signed-off-by: Avi Kivity

PPC: Fix race in mtmsr paravirt implementation

2012-03-05T12:52:24+00:00

The current implementation of mtmsr and mtmsrd are racy in that it does:

  * check (int_pending == 0)
  ---> host sets int_pending = 1 <---
  * write shared page
  * done

while instead we should check for int_pending after the shared page is written.

Signed-off-by: Bharat Bhushan 
Signed-off-by: Alexander Graf 
Signed-off-by: Avi Kivity

KVM: PPC: Make PV mtmsrd L=1 work with r30 and r31

2010-10-24T08:52:14+00:00

We had an arbitrary limitation in mtmsrd L=1 that kept us from using r30 and
r31 as input registers. Let's get rid of that and get more potential speedups!

Signed-off-by: Alexander Graf