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2017-01-09KVM: PPC: Book3S HV: Save/restore XER in checkpointed register statePaul Mackerras
commit 0d808df06a44200f52262b6eb72bcb6042f5a7c5 upstream. When switching from/to a guest that has a transaction in progress, we need to save/restore the checkpointed register state. Although XER is part of the CPU state that gets checkpointed, the code that does this saving and restoring doesn't save/restore XER. This fixes it by saving and restoring the XER. To allow userspace to read/write the checkpointed XER value, we also add a new ONE_REG specifier. The visible effect of this bug is that the guest may see its XER value being corrupted when it uses transactions. Fixes: e4e38121507a ("KVM: PPC: Book3S HV: Add transactional memory support") Fixes: 0a8eccefcb34 ("KVM: PPC: Book3S HV: Add missing code for transaction reclaim on guest exit") Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-16KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 registerThomas Huth
commit fa73c3b25bd8d0d393dc6109a1dba3c2aef0451e upstream. The MMCR2 register is available twice, one time with number 785 (privileged access), and one time with number 769 (unprivileged, but it can be disabled completely). In former times, the Linux kernel was using the unprivileged register 769 only, but since commit 8dd75ccb571f3c92c ("powerpc: Use privileged SPR number for MMCR2"), it uses the privileged register 785 instead. The KVM-PR code then of course also switched to use the SPR 785, but this is causing older guest kernels to crash, since these kernels still access 769 instead. So to support older kernels with KVM-PR again, we have to support register 769 in KVM-PR, too. Fixes: 8dd75ccb571f3c92c48014b3dabd3d51a115ab41 Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24ppc32: fix copy_from_user()Al Viro
commit 224264657b8b228f949b42346e09ed8c90136a8e upstream. should clear on access_ok() failures. Also remove the useless range truncation logics. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15crypto: nx-842 - Mask XERS0 bit in return valueHaren Myneni
[ Upstream commit 6333ed8f26cf77311088d2e2b7cf16d8480bcbb2 ] NX842 coprocessor sets 3rd bit in CR register with XER[S0] which is nothing to do with NX request. Since this bit can be set with other valuable return status, mast this bit. One of other bits (INITIATED, BUSY or REJECTED) will be returned for any given NX request. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24powerpc: Use privileged SPR number for MMCR2Thomas Huth
commit 8dd75ccb571f3c92c48014b3dabd3d51a115ab41 upstream. We are already using the privileged versions of MMCR0, MMCR1 and MMCRA in the kernel, so for MMCR2, we should better use the privileged versions, too, to be consistent. Fixes: 240686c13687 ("powerpc: Initialise PMU related regs on Power8") Suggested-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-24powerpc: Fix definition of SIAR and SDAR registersThomas Huth
commit d23fac2b27d94aeb7b65536a50d32bfdc21fe01e upstream. The SIAR and SDAR registers are available twice, one time as SPRs 780 / 781 (unprivileged, but read-only), and one time as the SPRs 796 / 797 (privileged, but read and write). The Linux kernel code currently uses the unprivileged SPRs - while this is OK for reading, writing to that register of course does not work. Since the KVM code tries to write to this register, too (see the mtspr in book3s_hv_rmhandlers.S), the contents of this register sometimes get lost for the guests, e.g. during migration of a VM. To fix this issue, simply switch to the privileged SPR numbers instead. Signed-off-by: Thomas Huth <thuth@redhat.com> Acked-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-11powerpc: Fix bad inline asm constraint in create_zero_mask()Anton Blanchard
commit b4c112114aab9aff5ed4568ca5e662bb02cdfe74 upstream. In create_zero_mask() we have: addi %1,%2,-1 andc %1,%1,%2 popcntd %0,%1 using the "r" constraint for %2. r0 is a valid register in the "r" set, but addi X,r0,X turns it into an li: li r7,-1 andc r7,r7,r0 popcntd r4,r7 Fix this by using the "b" constraint, for which r0 is not a valid register. This was found with a kernel build using gcc trunk, narrowed down to when -frename-registers was enabled at -O2. It is just luck however that we aren't seeing this on older toolchains. Thanks to Segher for working with me to find this issue. Fixes: d0cebfa650a0 ("powerpc: word-at-a-time optimization for 64-bit Little Endian") Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-04powerpc: scan_features() updates incorrect bits for REAL_LEAnton Blanchard
commit 6997e57d693b07289694239e52a10d2f02c3a46f upstream. The REAL_LE feature entry in the ibm_pa_feature struct is missing an MMU feature value, meaning all the remaining elements initialise the wrong values. This means instead of checking for byte 5, bit 0, we check for byte 0, bit 0, and then we incorrectly set the CPU feature bit as well as MMU feature bit 1 and CPU user feature bits 0 and 2 (5). Checking byte 0 bit 0 (IBM numbering), means we're looking at the "Memory Management Unit (MMU)" feature - ie. does the CPU have an MMU. In practice that bit is set on all platforms which have the property. This means we set CPU_FTR_REAL_LE always. In practice that seems not to matter because all the modern cpus which have this property also implement REAL_LE, and we've never needed to disable it. We're also incorrectly setting MMU feature bit 1, which is: #define MMU_FTR_TYPE_8xx 0x00000002 Luckily the only place that looks for MMU_FTR_TYPE_8xx is in Book3E code, which can't run on the same cpus as scan_features(). So this also doesn't matter in practice. Finally in the CPU user feature mask, we're setting bits 0 and 2. Bit 2 is not currently used, and bit 0 is: #define PPC_FEATURE_PPC_LE 0x00000001 Which says the CPU supports the old style "PPC Little Endian" mode. Again this should be harmless in practice as no 64-bit CPUs implement that mode. Fix the code by adding the missing initialisation of the MMU feature. Also add a comment marking CPU user feature bit 2 (0x4) as reserved. It would be unsafe to start using it as old kernels incorrectly set it. Fixes: 44ae3ab3358e ("powerpc: Free up some CPU feature bits by moving out MMU-related features") Signed-off-by: Anton Blanchard <anton@samba.org> [mpe: Flesh out changelog, add comment reserving 0x4] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-16powerpc/powernv: Fix OPAL_CONSOLE_FLUSH prototype and usagesRussell Currey
commit c88c5d43732a0356f99e5e4d1ad62ab1ea516b81 upstream. The recently added OPAL API call, OPAL_CONSOLE_FLUSH, originally took no parameters and returned nothing. The call was updated to accept the terminal number to flush, and returned various values depending on the state of the output buffer. The prototype has been updated and its usage in the OPAL kmsg dumper has been modified to support its new behaviour as an incremental flush. Signed-off-by: Russell Currey <ruscur@russell.cc> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-16powerpc/powernv: Add a kmsg_dumper that flushes console output on panicRussell Currey
commit affddff69c55eb68969448f35f59054a370bc7c1 upstream. On BMC machines, console output is controlled by the OPAL firmware and is only flushed when its pollers are called. When the kernel is in a panic state, it no longer calls these pollers and thus console output does not completely flush, causing some output from the panic to be lost. Output is only actually lost when the kernel is configured to not power off or reboot after panic (i.e. CONFIG_PANIC_TIMEOUT is set to 0) since OPAL flushes the console buffer as part of its power down routines. Before this patch, however, only partial output would be printed during the timeout wait. This patch adds a new kmsg_dumper which gets called at panic time to ensure panic output is not lost. It accomplishes this by calling OPAL_CONSOLE_FLUSH in the OPAL API, and if that is not available, the pollers are called enough times to (hopefully) completely flush the buffer. The flushing mechanism will only affect output printed at and before the kmsg_dump call in kernel/panic.c:panic(). As such, the "end Kernel panic" message may still be truncated as follows: >Call Trace: >[c000000f1f603b00] [c0000000008e9458] dump_stack+0x90/0xbc (unreliable) >[c000000f1f603b30] [c0000000008e7e78] panic+0xf8/0x2c4 >[c000000f1f603bc0] [c000000000be4860] mount_block_root+0x288/0x33c >[c000000f1f603c80] [c000000000be4d14] prepare_namespace+0x1f4/0x254 >[c000000f1f603d00] [c000000000be43e8] kernel_init_freeable+0x318/0x350 >[c000000f1f603dc0] [c00000000000bd74] kernel_init+0x24/0x130 >[c000000f1f603e30] [c0000000000095b0] ret_from_kernel_thread+0x5c/0xac >---[ end Kernel panic - not This functionality is implemented as a kmsg_dumper as it seems to be the most sensible way to introduce platform-specific functionality to the panic function. Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25powerpc/eeh: Fix stale cached primary busGavin Shan
commit 05ba75f848647135f063199dc0e9f40fee769724 upstream. When PE is created, its primary bus is cached to pe->bus. At later point, the cached primary bus is returned from eeh_pe_bus_get(). However, we could get stale cached primary bus and run into kernel crash in one case: full hotplug as part of fenced PHB error recovery releases all PCI busses under the PHB at unplugging time and recreate them at plugging time. pe->bus is still dereferencing the PCI bus that was released. This adds another PE flag (EEH_PE_PRI_BUS) to represent the validity of pe->bus. pe->bus is updated when its first child EEH device is online and the flag is set. Before unplugging in full hotplug for error recovery, the flag is cleared. Fixes: 8cdb2833 ("powerpc/eeh: Trace PCI bus from PE") Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reported-by: Pradipta Ghosh <pradghos@in.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31powerpc/module: Handle R_PPC64_ENTRY relocationsUlrich Weigand
commit a61674bdfc7c2bf909c4010699607b62b69b7bec upstream. GCC 6 will include changes to generated code with -mcmodel=large, which is used to build kernel modules on powerpc64le. This was necessary because the large model is supposed to allow arbitrary sizes and locations of the code and data sections, but the ELFv2 global entry point prolog still made the unconditional assumption that the TOC associated with any particular function can be found within 2 GB of the function entry point: func: addis r2,r12,(.TOC.-func)@ha addi r2,r2,(.TOC.-func)@l .localentry func, .-func To remove this assumption, GCC will now generate instead this global entry point prolog sequence when using -mcmodel=large: .quad .TOC.-func func: .reloc ., R_PPC64_ENTRY ld r2, -8(r12) add r2, r2, r12 .localentry func, .-func The new .reloc triggers an optimization in the linker that will replace this new prolog with the original code (see above) if the linker determines that the distance between .TOC. and func is in range after all. Since this new relocation is now present in module object files, the kernel module loader is required to handle them too. This patch adds support for the new relocation and implements the same optimization done by the GNU linker. Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31powerpc: Make {cmp}xchg* and their atomic_ versions fully orderedBoqun Feng
commit 81d7a3294de7e9828310bbf986a67246b13fa01e upstream. According to memory-barriers.txt, xchg*, cmpxchg* and their atomic_ versions all need to be fully ordered, however they are now just RELEASE+ACQUIRE, which are not fully ordered. So also replace PPC_RELEASE_BARRIER and PPC_ACQUIRE_BARRIER with PPC_ATOMIC_ENTRY_BARRIER and PPC_ATOMIC_EXIT_BARRIER in __{cmp,}xchg_{u32,u64} respectively to guarantee fully ordered semantics of atomic{,64}_{cmp,}xchg() and {cmp,}xchg(), as a complement of commit b97021f85517 ("powerpc: Fix atomic_xxx_return barrier semantics") This patch depends on patch "powerpc: Make value-returning atomics fully ordered" for PPC_ATOMIC_ENTRY_BARRIER definition. Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31powerpc: Make value-returning atomics fully orderedBoqun Feng
commit 49e9cf3f0c04bf76ffa59242254110309554861d upstream. According to memory-barriers.txt: > Any atomic operation that modifies some state in memory and returns > information about the state (old or new) implies an SMP-conditional > general memory barrier (smp_mb()) on each side of the actual > operation ... Which mean these operations should be fully ordered. However on PPC, PPC_ATOMIC_ENTRY_BARRIER is the barrier before the actual operation, which is currently "lwsync" if SMP=y. The leading "lwsync" can not guarantee fully ordered atomics, according to Paul Mckenney: https://lkml.org/lkml/2015/10/14/970 To fix this, we define PPC_ATOMIC_ENTRY_BARRIER as "sync" to guarantee the fully-ordered semantics. This also makes futex atomics fully ordered, which can avoid possible memory ordering problems if userspace code relies on futex system call for fully ordered semantics. Fixes: b97021f85517 ("powerpc: Fix atomic_xxx_return barrier semantics") Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-16Partial revert of "powerpc: Individual System V IPC system calls"Michael Ellerman
This partially reverts commit a34236155afb1cc41945e58388ac988431bcb0b8. While reviewing the glibc patch to exploit the individual IPC calls, Arnd & Andreas noticed that we were still requiring userspace to pass IPC_64 in order to get the new style IPC API. With a bit of cleanup in the kernel we can drop that requirement, and instead only provide the new style API, which will simplify things for userspace. Rather than try and sneak that patch into 4.4, instead we will drop the individual IPC calls for powerpc, and merge them again in 4.5 once the cleanup patch has gone in. Because we've already added sys_mlock2() as syscall #378, we don't do a full revert of the IPC calls. Instead we drop the __NR #defines, and send those now undefined syscall numbers to sys_ni_syscall(). This leaves a gap in the syscall numbers, but we'll reuse them when we merge the individual IPC calls. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Arnd Bergmann <arnd@arndb.de>
2015-11-23powerpc/tm: Block signal return setting invalid MSR stateMichael Neuling
Currently we allow both the MSR T and S bits to be set by userspace on a signal return. Unfortunately this is a reserved configuration and will cause a TM Bad Thing exception if attempted (via rfid). This patch checks for this case in both the 32 and 64 bit signals code. If both T and S are set, we mark the context as invalid. Found using a syscall fuzzer. Fixes: 2b0a576d15e0 ("powerpc: Add new transactional memory state to the signal context") Cc: stable@vger.kernel.org # v3.9+ Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-16powerpc: Wire up sys_mlock2()Michael Ellerman
The selftest passes on 64-bit LE and 32-bit BE. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-09kmap_atomic_to_page() has no users, remove itNicolas Pitre
Removal started in commit 5bbeed12bdc3 ("sparc32: drop unused kmap_atomic_to_page"). Let's do it across the whole tree. Signed-off-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05Merge tag 'powerpc-4.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Kconfig: remove BE-only platforms from LE kernel build from Boqun Feng - Refresh ps3_defconfig from Geoff Levand - Emit GNU & SysV hashes for the vdso from Michael Ellerman - Define an enum for the bolted SLB indexes from Anshuman Khandual - Use a local to avoid multiple calls to get_slb_shadow() from Michael Ellerman - Add gettimeofday() benchmark from Michael Neuling - Avoid link stack corruption in __get_datapage() from Michael Neuling - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar K.V - Add ppc64le_defconfig from Michael Ellerman - pseries: extract of_helpers module from Andy Shevchenko - Correct string length in pseries_of_derive_parent() from Nathan Fontenot - Free the MSI bitmap if it was slab allocated from Denis Kirjanov - Shorten irq_chip name for the SIU from Christophe Leroy - Wait 1s for secondaries to enter OPAL during kexec from Samuel Mendoza-Jonas - Fix _ALIGN_* errors due to type difference, from Aneesh Kumar K.V - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from Colin Ian King - Disable hugepd for 64K page size, from Aneesh Kumar K.V - Differentiate between hugetlb and THP during page walk from Aneesh Kumar K.V - Make PCI non-optional for pseries from Michael Ellerman - Individual System V IPC system calls from Sam bobroff - Add selftest of unmuxed IPC calls from Michael Ellerman - discard .exit.data at runtime from Stephen Rothwell - Delete old orphaned PrPMC 280/2800 DTS and boot file, from Paul Gortmaker - Use of_get_next_parent to simplify code from Christophe Jaillet - Paginate some xmon output from Sam bobroff - Add some more elements to the xmon PACA dump from Michael Ellerman - Allow the tm-syscall selftest to build with old headers from Michael Ellerman - Run EBB selftests only on POWER8 from Denis Kirjanov - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael Ellerman - Avoid reference to potentially freed memory in prom.c from Christophe Jaillet - Quieten boot wrapper output with run_cmd from Geoff Levand - EEH fixes and cleanups from Gavin Shan - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael Ellerman - Fix section mismatch warning in msi_bitmap_alloc() from Denis Kirjanov - Fix ps3-lpm white space from Rudhresh Kumar J - Fix ps3-vuart null dereference from Colin King - nvram: Add missing kfree in error path from Christophe Jaillet - nvram: Fix function name in some errors messages, from Christophe Jaillet - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro Koskinen - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov - cxl: Free virtual PHB when removing from Andrew Donnellan - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from Michael Ellerman - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building with O= from Michael Ellerman - Freescale updates from Scott: Highlights include 64-bit book3e kexec/kdump support, a rework of the qoriq clock driver, device tree changes including qoriq fman nodes, support for a new 85xx board, and some fixes. - MPC5xxx updates from Anatolij: Highlights include a driver for MPC512x LocalPlus Bus FIFO with its device tree binding documentation, mpc512x device tree updates and some minor fixes. * tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (106 commits) powerpc/msi: Fix section mismatch warning in msi_bitmap_alloc() powerpc/prom: Use of_get_next_parent() in of_get_ibm_chip_id() powerpc/pseries: Correct string length in pseries_of_derive_parent() powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry powerpc/mpc85xx: Add FSL QorIQ DPAA FMan support to the SoC device tree(s) powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes powerpc: handle error case in cpm_muram_alloc() powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake powerpc/book3e-64: Enable kexec powerpc/book3e-64/kexec: Set "r4 = 0" when entering spinloop powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32 powerpc/book3e-64/kexec: Enable SMP release powerpc/book3e-64/kexec: create an identity TLB mapping powerpc/book3e-64: Don't limit paca to 256 MiB powerpc/book3e/kdump: Enable crash_kexec_wait_realmode powerpc/book3e: support CONFIG_RELOCATABLE powerpc/booke64: Fix args to copy_and_flush powerpc/book3e-64: rename interrupt_end_book3e with __end_interrupts powerpc/e6500: kexec: Handle hardware threads ...
2015-11-05Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge patch-bomb from Andrew Morton: - inotify tweaks - some ocfs2 updates (many more are awaiting review) - various misc bits - kernel/watchdog.c updates - Some of mm. I have a huge number of MM patches this time and quite a lot of it is quite difficult and much will be held over to next time. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits) selftests: vm: add tests for lock on fault mm: mlock: add mlock flags to enable VM_LOCKONFAULT usage mm: introduce VM_LOCKONFAULT mm: mlock: add new mlock system call mm: mlock: refactor mlock, munlock, and munlockall code kasan: always taint kernel on report mm, slub, kasan: enable user tracking by default with KASAN=y kasan: use IS_ALIGNED in memory_is_poisoned_8() kasan: Fix a type conversion error lib: test_kasan: add some testcases kasan: update reference to kasan prototype repo kasan: move KASAN_SANITIZE in arch/x86/boot/Makefile kasan: various fixes in documentation kasan: update log messages kasan: accurately determine the type of the bad access kasan: update reported bug types for kernel memory accesses kasan: update reported bug types for not user nor kernel memory accesses mm/kasan: prevent deadlock in kasan reporting mm/kasan: don't use kasan shadow pointer in generic functions mm/kasan: MODULE_VADDR is not available on all archs ...
2015-11-05mm: mlock: add mlock flags to enable VM_LOCKONFAULT usageEric B Munson
The previous patch introduced a flag that specified pages in a VMA should be placed on the unevictable LRU, but they should not be made present when the area is created. This patch adds the ability to set this state via the new mlock system calls. We add MLOCK_ONFAULT for mlock2 and MCL_ONFAULT for mlockall. MLOCK_ONFAULT will set the VM_LOCKONFAULT modifier for VM_LOCKED. MCL_ONFAULT should be used as a modifier to the two other mlockall flags. When used with MCL_CURRENT, all current mappings will be marked with VM_LOCKED | VM_LOCKONFAULT. When used with MCL_FUTURE, the mm->def_flags will be marked with VM_LOCKED | VM_LOCKONFAULT. When used with both MCL_CURRENT and MCL_FUTURE, all current mappings and mm->def_flags will be marked with VM_LOCKED | VM_LOCKONFAULT. Prior to this patch, mlockall() will unconditionally clear the mm->def_flags any time it is called without MCL_FUTURE. This behavior is maintained after adding MCL_ONFAULT. If a call to mlockall(MCL_FUTURE) is followed by mlockall(MCL_CURRENT), the mm->def_flags will be cleared and new VMAs will be unlocked. This remains true with or without MCL_ONFAULT in either mlockall() invocation. munlock() will unconditionally clear both vma flags. munlockall() unconditionally clears for VMA flags on all VMAs and in the mm->def_flags field. Signed-off-by: Eric B Munson <emunson@akamai.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "First batch of KVM changes for 4.4. s390: A bunch of fixes and optimizations for interrupt and time handling. PPC: Mostly bug fixes. ARM: No big features, but many small fixes and prerequisites including: - a number of fixes for the arch-timer - introducing proper level-triggered semantics for the arch-timers - a series of patches to synchronously halt a guest (prerequisite for IRQ forwarding) - some tracepoint improvements - a tweak for the EL2 panic handlers - some more VGIC cleanups getting rid of redundant state x86: Quite a few changes: - support for VT-d posted interrupts (i.e. PCI devices can inject interrupts directly into vCPUs). This introduces a new component (in virt/lib/) that connects VFIO and KVM together. The same infrastructure will be used for ARM interrupt forwarding as well. - more Hyper-V features, though the main one Hyper-V synthetic interrupt controller will have to wait for 4.5. These will let KVM expose Hyper-V devices. - nested virtualization now supports VPID (same as PCID but for vCPUs) which makes it quite a bit faster - for future hardware that supports NVDIMM, there is support for clflushopt, clwb, pcommit - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in userspace, which reduces the attack surface of the hypervisor - obligatory smattering of SMM fixes - on the guest side, stable scheduler clock support was rewritten to not require help from the hypervisor" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits) KVM: VMX: Fix commit which broke PML KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0() KVM: x86: allow RSM from 64-bit mode KVM: VMX: fix SMEP and SMAP without EPT KVM: x86: move kvm_set_irq_inatomic to legacy device assignment KVM: device assignment: remove pointless #ifdefs KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic KVM: x86: zero apic_arb_prio on reset drivers/hv: share Hyper-V SynIC constants with userspace KVM: x86: handle SMBASE as physical address in RSM KVM: x86: add read_phys to x86_emulate_ops KVM: x86: removing unused variable KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr() KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings KVM: arm/arm64: Optimize away redundant LR tracking KVM: s390: use simple switch statement as multiplexer KVM: s390: drop useless newline in debugging data KVM: s390: SCA must not cross page boundaries KVM: arm: Do not indent the arguments of DECLARE_BITMAP ...
2015-11-05Merge branch 'next' of git://git.denx.de/linux-denx-agust into nextMichael Ellerman
MPC5xxx updates from Anatolij: "Highlights include a driver for MPC512x LocalPlus Bus FIFO with its device tree binding documentation, mpc512x device tree updates and some minor fixes."
2015-11-04Merge tag 'kvm-arm-for-4.4' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/ARM Changes for v4.4-rc1 Includes a number of fixes for the arch-timer, introducing proper level-triggered semantics for the arch-timers, a series of patches to synchronously halt a guest (prerequisite for IRQ forwarding), some tracepoint improvements, a tweak for the EL2 panic handlers, some more VGIC cleanups getting rid of redundant state, and finally a stylistic change that gets rid of some ctags warnings. Conflicts: arch/x86/include/asm/kvm_host.h
2015-10-27powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same ↵Kevin Hao
tlb entry In order to workaround Erratum A-008139, we have to invalidate the tlb entry with tlbilx before overwriting. Due to the performance consideration, we don't add any memory barrier when acquire/release the tcd lock. This means the two load instructions for esel_next do have the possibility to return different value. This is definitely not acceptable due to the Erratum A-008139. We have two options to fix this issue: a) Add memory barrier when acquire/release tcd lock to order the load/store to esel_next. b) Just make sure to invalidate and write to the same tlb entry and tolerate the race that we may get the wrong value and overwrite the tlb entry just updated by the other thread. We observe better performance using option b. So reserve an additional register to save the value of the esel_next. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-27Merge branch 'clock' into HEADScott Wood
This is a major overhaul of the clk-qoriq driver, which I'm merging via PPC with Stephen Boyd's ack in order to apply subsequent PPC patches that depend on it.
2015-10-27powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32Scott Wood
The way VIRT_PHYS_OFFSET is not correct on book3e-64, because it does not account for CONFIG_RELOCATABLE other than via the 32-bit-only virt_phys_offset. book3e-64 can (and if the comment about a GCC miscompilation is still relevant, should) use the normal ppc64 __va/__pa. At this point, only booke-32 will use VIRT_PHYS_OFFSET, so given the issues with its calculation, restrict its definition to booke-32. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-27powerpc/book3e: support CONFIG_RELOCATABLETiejun Chen
book3e is different with book3s since 3s includes the exception vectors code in head_64.S as it relies on absolute addressing which is only possible within this compilation unit. So we have to get that label address with got. And when boot a relocated kernel, we should reset ipvr properly again after .relocate. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> [scottwood: cleanup and ifdef removal] Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-23Merge tag 'powerpc-4.3-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8" from Paul - Handle irq_happened flag correctly in off-line loop from Paul - Validate rtas.entry before calling enter_rtas() from Vasant * tag 'powerpc-4.3-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/rtas: Validate rtas.entry before calling enter_rtas() powerpc/powernv: Handle irq_happened flag correctly in off-line loop powerpc: Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8"
2015-10-22KVM: Add kvm_arch_vcpu_{un}blocking callbacksChristoffer Dall
Some times it is useful for architecture implementations of KVM to know when the VCPU thread is about to block or when it comes back from blocking (arm/arm64 needs to know this to properly implement timers, for example). Therefore provide a generic architecture callback function in line with what we do elsewhere for KVM generic-arch interactions. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-22powerpc: mpc512x: drop bogus and unused psc register bit definitionsUwe Kleine-König
These were introduced in commit 25ae3a0739c6 ("[POWERPC] mpc512x: Add MPC512x PSC support to MPC52xx psc driver") and never used. Moreover according to the datasheet[1] MEMERROR is bit 25 (0x40) and ORERR is bit 27 (0x10). [1] MPC5125RM Rev. 2; 11/2009 Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Anatolij Gustschin <agust@denx.de>
2015-10-22powerpc/512x: add LocalPlus Bus FIFO device driverAlexander Popov
This driver for Freescale MPC512x LocalPlus Bus FIFO (called SCLPC in the Reference Manual) allows Direct Memory Access transfers between RAM and peripheral devices on LocalPlus Bus. Signed-off-by: Alexander Popov <alex.popov@linux.com> Signed-off-by: Anatolij Gustschin <agust@denx.de>
2015-10-21powerpc/fsl: Move fsl_guts.h out of arch/powerpcScott Wood
Freescale's Layerscape ARM chips use the same structure. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-21powerpc: Revert "Use the POWER8 Micro Partition Prefetch Engine in KVM HV on ↵Paul Mackerras
POWER8" This reverts commit 9678cdaae939 ("Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8") because the original commit had multiple, partly self-cancelling bugs, that could cause occasional memory corruption. In fact the logmpp instruction was incorrectly using register r0 as the source of the buffer address and operation code, and depending on what was in r0, it would either do nothing or corrupt the 64k page pointed to by r0. The logmpp instruction encoding and the operation code definitions could be corrected, but then there is the problem that there is no clearly defined way to know when the hardware has finished writing to the buffer. The original commit attempted to work around this by aborting the write-out before starting the prefetch, but this is ineffective in the case where the virtual core is now executing on a different physical core from the one where the write-out was initiated. These problems plus advice from the hardware designers not to use the function (since the measured performance improvement from using the feature was actually mostly negative), mean that reverting the code is the best option. Fixes: 9678cdaae939 ("Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8") Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-16Merge tag 'powerpc-4.3-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Re-enable CONFIG_SCSI_DH in our defconfigs - Remove unused os_area_db_id_video_mode - cxl: fix leak of IRQ names in cxl_free_afu_irqs() from Andrew - cxl: fix leak of ctx->irq_bitmap when releasing context via kernel API from Andrew - cxl: fix leak of ctx->mapping when releasing kernel API contexts from Andrew - cxl: Workaround malformed pcie packets on some cards from Philippe - cxl: Fix number of allocated pages in SPA from Christophe Lombard - Fix checkstop in native_hpte_clear() with lockdep from Cyril - Panic on unhandled Machine Check on powernv from Daniel - selftests/powerpc: Fix build failure of load_unaligned_zeropad test * tag 'powerpc-4.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: selftests/powerpc: Fix build failure of load_unaligned_zeropad test powerpc/powernv: Panic on unhandled Machine Check powerpc: Fix checkstop in native_hpte_clear() with lockdep cxl: Fix number of allocated pages in SPA cxl: Workaround malformed pcie packets on some cards cxl: fix leak of ctx->mapping when releasing kernel API contexts cxl: fix leak of ctx->irq_bitmap when releasing context via kernel API cxl: fix leak of IRQ names in cxl_free_afu_irqs() powerpc/ps3: Remove unused os_area_db_id_video_mode powerpc/configs: Re-enable CONFIG_SCSI_DH
2015-10-15powerpc: Individual System V IPC system callsSam bobroff
This patch provides individual system call numbers for the following System V IPC system calls, on PowerPC, so that they do not need to be multiplexed: * semop, semget, semctl, semtimedop * msgsnd, msgrcv, msgget, msgctl * shmat, shmdt, shmget, shmctl Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-15KVM: PPC: e500: Emulate TMCFG0 TMRN registerTudor Laurentiu
Emulate TMCFG0 TMRN register exposing one HW thread per vcpu. Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> [Laurentiu.Tudor@freescale.com: rebased on latest kernel, use define instead of hardcoded value, moved code in own function] Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com> Acked-by: Scott Wood <scotttwood@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-15powerpc/e6500: add TMCFG0 register definitionTudor Laurentiu
The register is not currently used in the base kernel but will be in a forthcoming kvm patch. Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com> Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-12powerpc/mm: Differentiate between hugetlb and THP during page walkAneesh Kumar K.V
We need to properly identify whether a hugepage is an explicit or a transparent hugepage in follow_huge_addr(). We used to depend on hugepage shift argument to do that. But in some case that can result in wrong results. For ex: On finding a transparent hugepage we set hugepage shift to PMD_SHIFT. But we can end up clearing the thp pte, via pmdp_huge_get_and_clear. We do prevent reusing the pfn page via the usage of kick_all_cpus_sync(). But that happens after we updated the pte to 0. Hence in follow_huge_addr() we can find hugepage shift set, but transparent huge page check fail for a thp pte. NOTE: We fixed a variant of this race against thp split in commit 691e95fd7396905a38d98919e9c150dbc3ea21a3 ("powerpc/mm/thp: Make page table walk safe against thp split/collapse") Without this patch, we may hit the BUG_ON(flags & FOLL_GET) in follow_page_mask occasionally. In the long term, we may want to switch ppc64 64k page size config to enable CONFIG_ARCH_WANT_GENERAL_HUGETLB Reported-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-12powerpc/mm: Disable hugepd for 64K page size.Aneesh Kumar K.V
After commit e2b3d202d1dba8f3546ed28224ce485bc50010be ("powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format"), we don't need to support is_hugepd() for 64K page size. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-09powerpc: Fix _ALIGN_* errors due to type difference.Aneesh Kumar K.V
This avoid errors like unsigned int usize = 1 << 30; int size = 1 << 30; unsigned long addr = 64UL << 30 ; value = _ALIGN_DOWN(addr, usize); -> 0 value = _ALIGN_DOWN(addr, size); -> 0x1000000000 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-09powerpc: Fix checkstop in native_hpte_clear() with lockdepCyril Bur
native_hpte_clear() is called in real mode from two places: - Early in boot during htab initialisation if firmware assisted dump is active. - Late in the kexec path. In both contexts there is no need to disable interrupts are they are already disabled. Furthermore, locking around the tlbie() is only required for pre POWER5 hardware. On POWER5 or newer hardware concurrent tlbie()s work as expected and on pre POWER5 hardware concurrent tlbie()s could result in deadlock. This code would only be executed at crashdump time, during which all bets are off, concurrent tlbie()s are unlikely and taking locks is unsafe therefore the best course of action is to simply do nothing. Concurrent tlbie()s are not possible in the first case as secondary CPUs have not come up yet. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-08arch/powerpc: provide zero_bytemask() for big-endianChris Metcalf
For some reason, only the little-endian flavor of powerpc provided the zero_bytemask() implementation. Reported-by: Michal Sojka <sojkam1@fel.cvut.cz> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
2015-10-06word-at-a-time.h: fix some Kbuild filesChris Metcalf
arch/tile added word-at-a-time.h after the patch that added generic-y entries; the generic-y entry is now stale. arch/h8300 is newer than the generic-y patch for word-at-a-time.h, and needs a generic-y entry. arch/powerpc seems to have gotten a generic-y entry by mistake in the first patch; this change removes it. Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
2015-10-05powerpc/msi: Free the bitmap if it was slab allocatedDenis Kirjanov
During the MSI bitmap test on boot kmemleak spews the following trace: unreferenced object 0xc00000016e86c900 (size 64): comm "swapper/0", pid 1, jiffies 4294893173 (age 518.024s) hex dump (first 32 bytes): 00 00 01 ff 7f ff 7f 37 00 00 00 00 00 00 00 00 .......7........ ff ff ff ff ff ff ff ff 01 ff ff ff ff ff ff ff ................ backtrace: [<c00000000003eebc>] .zalloc_maybe_bootmem+0x3c/0x380 [<c000000000042d6c>] .msi_bitmap_alloc+0x3c/0xb0 [<c000000000a9aff8>] .msi_bitmap_selftest+0x30/0x2b4 [<c0000000000090f4>] .do_one_initcall+0xd4/0x270 [<c000000000a8e250>] .kernel_init_freeable+0x1a0/0x280 [<c000000000009b5c>] .kernel_init+0x1c/0x120 [<c000000000007fbc>] .ret_from_kernel_thread+0x58/0x9c Add a flag to msi_bitmap for tracking allocations from slab and memblock so we can properly free/handle memory in msi_bitmap_free(). Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> [mpe: Reword changelog & use bitmap_from_slab in the if] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-04Merge branch 'strscpy' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile Pull strscpy string copy function implementation from Chris Metcalf. Chris sent this during the merge window, but I waffled back and forth on the pull request, which is why it's going in only now. The new "strscpy()" function is definitely easier to use and more secure than either strncpy() or strlcpy(), both of which are horrible nasty interfaces that have serious and irredeemable problems. strncpy() has a useless return value, and doesn't NUL-terminate an overlong result. To make matters worse, it pads a short result with zeroes, which is a performance disaster if you have big buffers. strlcpy(), by contrast, is a mis-designed "fix" for strlcpy(), lacking the insane NUL padding, but having a differently broken return value which returns the original length of the source string. Which means that it will read characters past the count from the source buffer, and you have to trust the source to be properly terminated. It also makes error handling fragile, since the test for overflow is unnecessarily subtle. strscpy() avoids both these problems, guaranteeing the NUL termination (but not excessive padding) if the destination size wasn't zero, and making the overflow condition very obvious by returning -E2BIG. It also doesn't read past the size of the source, and can thus be used for untrusted source data too. So why did I waffle about this for so long? Every time we introduce a new-and-improved interface, people start doing these interminable series of trivial conversion patches. And every time that happens, somebody does some silly mistake, and the conversion patch to the improved interface actually makes things worse. Because the patch is mindnumbing and trivial, nobody has the attention span to look at it carefully, and it's usually done over large swatches of source code which means that not every conversion gets tested. So I'm pulling the strscpy() support because it *is* a better interface. But I will refuse to pull mindless conversion patches. Use this in places where it makes sense, but don't do trivial patches to fix things that aren't actually known to be broken. * 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: tile: use global strscpy() rather than private copy string: provide strscpy() Make asm/word-at-a-time.h available on all architectures
2015-10-01powerpc/mm: Add virt_to_pfn and use this instead of opencodingAneesh Kumar K.V
This add helper virt_to_pfn and remove the opencoded usage of the same. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-09-25Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "AMD fixes for bugs introduced in the 4.2 merge window, and a few PPC bug fixes too" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: disable halt_poll_ns as default for s390x KVM: x86: fix off-by-one in reserved bits check KVM: x86: use correct page table format to check nested page table reserved bits KVM: svm: do not call kvm_set_cr0 from init_vmcb KVM: x86: trap AMD MSRs for the TSeg base and mask KVM: PPC: Book3S: Take the kvm->srcu lock in kvmppc_h_logical_ci_load/store() KVM: PPC: Book3S HV: Pass the correct trap argument to kvmhv_commence_exit KVM: PPC: Book3S HV: Fix handling of interrupted VCPUs kvm: svm: reset mmu on VCPU reset
2015-09-25KVM: disable halt_poll_ns as default for s390xDavid Hildenbrand
We observed some performance degradation on s390x with dynamic halt polling. Until we can provide a proper fix, let's enable halt_poll_ns as default only for supported architectures. Architectures are now free to set their own halt_poll_ns default value. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-21powerpc: Wire up sys_membarrier()Michael Ellerman
The selftest passes on 64-bit LE & BE, and 32-bit. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>