linux/arch/mips/kvm
James Hogan 42aa12e74e MIPS: KVM: Move commpage so 0x0 is unmapped
The comm page which is mapped into the guest kernel address space at
0x0 has the unfortunate side effect of allowing guest kernel NULL
pointer dereferences to succeed. The only constraint on this address is
that it must be within 32KiB of 0x0, so that single lw/sw instructions
(which have 16-bit signed offset fields) can be used to access it, using
the zero register as a base.

So lets move the comm page as high as possible within that constraint so
that 0x0 can be left unmapped, at least for page sizes < 32KiB.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-15 23:58:36 +02:00
..
00README.txt KVM/MIPS32: Release notes and KVM module Makefile 2013-05-08 03:55:35 +02:00
Kconfig rcu: Make SRCU optional by using CONFIG_SRCU 2015-01-06 11:04:29 -08:00
Makefile MIPS: KVM: Move non-TLB handling code out of tlb.c 2016-06-14 11:02:42 +02:00
callback.c MIPS: KVM: Convert EXPORT_SYMBOL to _GPL 2016-01-24 03:13:24 +01:00
commpage.c MIPS: KVM: Move commpage so 0x0 is unmapped 2016-06-15 23:58:36 +02:00
commpage.h MIPS: KVM: Rename files to remove the prefix "kvm_" and "kvm_mips_" 2014-06-30 16:52:03 +02:00
dyntrans.c MIPS: KVM: Move commpage so 0x0 is unmapped 2016-06-15 23:58:36 +02:00
emulate.c MIPS: KVM: Add KScratch registers 2016-06-15 23:58:36 +02:00
fpu.S MIPS: KVM: Add base guest FPU support 2015-03-27 21:25:14 +00:00
interrupt.c MIPS: KVM: Convert code to kernel sized types 2016-06-14 11:02:41 +02:00
interrupt.h MIPS: KVM: Convert headers to kernel sized types 2016-06-14 11:02:40 +02:00
locore.S MIPS: KVM: Don't hardcode restored HWREna 2016-06-15 23:58:31 +02:00
mips.c MIPS: KVM: Add KScratch registers 2016-06-15 23:58:36 +02:00
mmu.c MIPS: KVM: Dump guest tlbs if kvm_get_inst() fails 2016-06-14 11:16:25 +02:00
msa.S MIPS: KVM: Add base guest MSA support 2015-03-27 21:25:19 +00:00
stats.c MIPS: KVM: Clean up kvm_exit trace event 2016-06-14 11:16:23 +02:00
tlb.c MIPS: KVM: Move commpage so 0x0 is unmapped 2016-06-15 23:58:36 +02:00
trace.h MIPS: KVM: Add KScratch registers 2016-06-15 23:58:36 +02:00
trap_emul.c MIPS: KVM: Add KScratch registers 2016-06-15 23:58:36 +02:00