linux/arch/powerpc
Paul Mackerras cf29b21595 KVM: PPC: Book3S HV: Synthesize segment fault if SLB lookup fails
When handling a hypervisor data or instruction storage interrupt (HDSI
or HISI), we look up the SLB entry for the address being accessed in
order to translate the effective address to a virtual address which can
be looked up in the guest HPT.  This lookup can occasionally fail due
to the guest replacing an SLB entry without invalidating the evicted
SLB entry.  In this situation an ERAT (effective to real address
translation cache) entry can persist and be used by the hardware even
though there is no longer a corresponding SLB entry.

Previously we would just deliver a data or instruction storage interrupt
(DSI or ISI) to the guest in this case.  However, this is not correct
and has been observed to cause guests to crash, typically with a
data storage protection interrupt on a store to the vmemmap area.

Instead, what we do now is to synthesize a data or instruction segment
interrupt.  That should cause the guest to reload an appropriate entry
into the SLB and retry the faulting instruction.  If it still faults,
we should find an appropriate SLB entry next time and be able to handle
the fault.

Tested-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-11-06 15:40:42 +11:00
..
boot powerpc/boot: Specify ABI v2 when building an LE boot wrapper 2015-09-16 22:05:55 +10:00
configs Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next 2015-08-27 20:13:12 +10:00
crypto crypto: powerpc/md5 - use md5 IV MD5_HX instead of their raw value 2015-05-18 12:20:20 +08:00
include KVM/ARM Changes for v4.4-rc1 2015-11-04 16:24:17 +01:00
kernel PCI updates for v4.3: 2015-09-25 11:16:53 -07:00
kvm KVM: PPC: Book3S HV: Synthesize segment fault if SLB lookup fails 2015-11-06 15:40:42 +11:00
lib powerpc32: memset: only use dcbz once cache is enabled 2015-09-17 10:36:53 +10:00
math-emu powerpc: Correct emulated mtfsf instruction 2014-04-07 10:33:11 +10:00
mm powerpc fixes for 4.3 2015-09-18 08:01:06 -07:00
net ppc: bpf: Add SKF_AD_CPU for ppc32 2015-02-20 15:19:43 -05:00
oprofile powerpc: Remove mtmsrd(), use existing mtmsr() 2015-07-13 15:47:28 +10:00
perf powerpc/perf: Change type of the bhrb_users variable 2015-07-27 14:31:44 +10:00
platforms Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-18 08:11:42 -07:00
sysdev Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-18 08:11:42 -07:00
xmon powerpc/xmon: Drop the valid variable completely in dump_segments() 2015-08-12 15:05:47 +10:00
Kconfig kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
Kconfig.debug powerpc: Make STRICT_MM_TYPECHECKS a config option 2015-05-11 19:53:59 +10:00
Makefile Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2015-09-08 14:12:19 -07:00
relocs_check.sh powerpc: Convert relocs_check to a shell script using grep 2015-03-23 14:47:39 +11:00