linux_dsm_epyc7002/arch
Nicholas Piggin 5e46e29e6a powerpc/64s/hash: convert SLB miss handlers to C
This patch moves SLB miss handlers completely to C, using the standard
exception handler macros to set up the stack and branch to C.

This can be done because the segment containing the kernel stack is
always bolted, so accessing it with relocation on will not cause an
SLB exception.

Arbitrary kernel memory may not be accessed when handling kernel space
SLB misses, so care should be taken there. However user SLB misses can
access any kernel memory, which can be used to move some fields out of
the paca (in later patches).

User SLB misses could quite easily reconcile IRQs and set up a first
class kernel environment and exit via ret_from_except, however that
doesn't seem to be necessary at the moment, so we only do that if a
bad fault is encountered.

[ Credit to Aneesh for bug fixes, error checks, and improvements to bad
  address handling, etc ]

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

Since RFC:
- Added MSR[RI] handling
- Fixed up a register loss bug exposed by irq tracing (Aneesh)
- Reject misses outside the defined kernel regions (Aneesh)
- Added several more sanity checks and error handling (Aneesh), we may
  look at consolidating these tests and tightenig up the code but for
  a first pass we decided it's better to check carefully.

Since v1:
- Fixed SLB cache corruption (Aneesh)
- Fixed untidy SLBE allocation "leak" in get_vsid error case
- Now survives some stress testing on real hardware

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 21:59:41 +10:00
..
alpha Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-08-24 09:25:39 -07:00
arc ARC: don't check for HIGHMEM pages in arch_dma_alloc 2018-09-04 13:21:38 -07:00
arm Fixes for KVM/ARM for Linux v4.19 v2: 2018-09-07 18:38:25 +02:00
arm64 KVM fixes for 4.19-rc3 2018-09-08 15:52:45 -07:00
c6x kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
h8300 Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
hexagon kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
ia64 ia64: Fix allnoconfig section mismatch for ioc_init/ioc_iommu_info 2018-08-22 14:12:47 -07:00
m68k m68k: fix early memory reservation for ColdFire MMU systems 2018-09-03 10:19:36 +10:00
microblaze kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
mips KVM fixes for 4.19-rc3 2018-09-08 15:52:45 -07:00
nds32 nds32: linker script: GCOV kernel may refers data in __exit 2018-09-05 10:16:26 +08:00
nios2 nios2: kconfig: remove duplicate DEBUG_STACK_USAGE symbol defintions 2018-08-27 09:47:20 +08:00
openrisc OpenRISC updates for 4.19 2018-08-23 14:09:37 -07:00
parisc Merge branch 'parisc-4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2018-08-22 14:06:37 -07:00
powerpc powerpc/64s/hash: convert SLB miss handlers to C 2018-09-19 21:59:41 +10:00
riscv RISC-V: Use a less ugly workaround for unused variable warnings 2018-08-28 12:58:36 -07:00
s390 KVM: s390: Properly lock mm context allow_gmap_hpage_1m setting 2018-09-04 11:40:26 +02:00
sh kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
sparc sparc: set a default 32-bit dma mask for OF devices 2018-09-02 10:02:04 +02:00
um kbuild: rename LDFLAGS to KBUILD_LDFLAGS 2018-08-24 08:22:08 +09:00
unicore32 mm: convert return type of handle_mm_fault() caller to vm_fault_t 2018-08-17 16:20:28 -07:00
x86 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-09 07:05:15 -07:00
xtensa Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
.gitignore
Kconfig Merge branch 'tlb-fixes' 2018-08-23 14:55:01 -07:00