linux/arch/powerpc
Hollis Blanchard fe4e771d5c KVM: ppc: fix userspace mapping invalidation on context switch
We used to defer invalidating userspace TLB entries until jumping out of the
kernel. This was causing MMU weirdness most easily triggered by using a pipe in
the guest, e.g. "dmesg | tail". I believe the problem was that after the guest
kernel changed the PID (part of context switch), the old process's mappings
were still present, and so copy_to_user() on the "return to new process" path
ended up using stale mappings.

Testing with large pages (64K) exposed the problem, probably because with 4K
pages, pressure on the TLB faulted all process A's mappings out before the
guest kernel could insert any for process B.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:26 +02:00
..
boot Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-12-28 16:54:33 -08:00
configs Merge branch 'next' of master.kernel.org:/pub/scm/linux/kernel/git/jwboyer/powerpc-4xx into next 2008-12-17 11:01:43 +11:00
include/asm KVM: ppc: fix userspace mapping invalidation on context switch 2008-12-31 16:52:26 +02:00
kernel KVM: ppc: create struct kvm_vcpu_44x and introduce container_of() accessor 2008-12-31 16:52:22 +02:00
kvm KVM: ppc: fix userspace mapping invalidation on context switch 2008-12-31 16:52:26 +02:00
lib Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-12-28 16:54:33 -08:00
math-emu powerpc: Add SPE/EFP math emulation for E500v1/v2 processors. 2008-12-03 08:19:16 -06:00
mm Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-12-28 16:54:33 -08:00
oprofile powerpc/cell/OProfile: Fix on-stack array size in activate spu profiling function 2008-10-31 16:13:51 +11:00
platforms Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-12-30 16:10:19 -08:00
sysdev Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-12-28 16:54:33 -08:00
xmon powerpc: Prepare xmon_save_regs for use with kdump 2008-12-23 15:13:28 +11:00
Kconfig Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-12-28 16:54:33 -08:00
Kconfig.debug powerpc: Allow the max stack trace depth to be configured 2008-12-03 20:46:35 +11:00
Makefile powerpc: Remove unncessary SPE related compiler flag 2008-12-03 08:19:10 -06:00