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* power/mm: update pte_write and pte_wrprotect to handle savedwriteAneesh Kumar K.V2017-03-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We use pte_write() to check whethwer the pte entry is writable. This is mostly used to later mark the pte read only if it is writable. The other use of pte_write() is to check whether the pte_entry is writable so that hardware page table entry can be marked accordingly. This is used in kvm where we look at qemu page table entry and update hardware hash page table for the guest with correct write enable bit. With the above, for the first usage we should also check the savedwrite bit so that we can correctly clear the savedwite bit. For the later, we add a new variant __pte_write(). With this we can revert write_protect_page part of 595cd8f256d2 ("mm/ksm: handle protnone saved writes when making page write protect"). But I left it as it is as an example code for savedwrite check. Fixes: c137a2757b886 ("powerpc/mm/autonuma: switch ppc64 to its own implementation of saved write") Link: http://lkml.kernel.org/r/1488203787-17849-2-git-send-email-aneesh.kumar@linux.vnet.ibm.com Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Rik van Riel <riel@surriel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* KVM: PPC: Book3S HV: Don't store values derivable from HPT orderDavid Gibson2017-01-311-9/+9
| | | | | | | | | | | Currently the kvm_hpt_info structure stores the hashed page table's order, and also the number of HPTEs it contains and a mask for its size. The last two can be easily derived from the order, so remove them and just calculate them as necessary with a couple of helper inlines. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Gather HPT related variables into sub-structureDavid Gibson2017-01-311-31/+31
| | | | | | | | | | | Currently, the powerpc kvm_arch structure contains a number of variables tracking the state of the guest's hashed page table (HPT) in KVM HV. This patch gathers them all together into a single kvm_hpt_info substructure. This makes life more convenient for the upcoming HPT resizing implementation. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Invalidate TLB on radix guest vcpu movementPaul Mackerras2017-01-311-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With radix, the guest can do TLB invalidations itself using the tlbie (global) and tlbiel (local) TLB invalidation instructions. Linux guests use local TLB invalidations for translations that have only ever been accessed on one vcpu. However, that doesn't mean that the translations have only been accessed on one physical cpu (pcpu) since vcpus can move around from one pcpu to another. Thus a tlbiel might leave behind stale TLB entries on a pcpu where the vcpu previously ran, and if that task then moves back to that previous pcpu, it could see those stale TLB entries and thus access memory incorrectly. The usual symptom of this is random segfaults in userspace programs in the guest. To cope with this, we detect when a vcpu is about to start executing on a thread in a core that is a different core from the last time it executed. If that is the case, then we mark the core as needing a TLB flush and then send an interrupt to any thread in the core that is currently running a vcpu from the same guest. This will get those vcpus out of the guest, and the first one to re-enter the guest will do the TLB flush. The reason for interrupting the vcpus executing on the old core is to cope with the following scenario: CPU 0 CPU 1 CPU 4 (core 0) (core 0) (core 1) VCPU 0 runs task X VCPU 1 runs core 0 TLB gets entries from task X VCPU 0 moves to CPU 4 VCPU 0 runs task X Unmap pages of task X tlbiel (still VCPU 1) task X moves to VCPU 1 task X runs task X sees stale TLB entries That is, as soon as the VCPU starts executing on the new core, it could unmap and tlbiel some page table entries, and then the task could migrate to one of the VCPUs running on the old core and potentially see stale TLB entries. Since the TLB is shared between all the threads in a core, we only use the bit of kvm->arch.need_tlb_flush corresponding to the first thread in the core. To ensure that we don't have a window where we can miss a flush, this moves the clearing of the bit from before the actual flush to after it. This way, two threads might both do the flush, but we prevent the situation where one thread can enter the guest before the flush is finished. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* KVM: PPC: Book3S HV: Make HPT-specific hypercalls return error in radix modePaul Mackerras2017-01-311-0/+14
| | | | | | | | | | If the guest is in radix mode, then it doesn't have a hashed page table (HPT), so all of the hypercalls that manipulate the HPT can't work and should return an error. This adds checks to make them return H_FUNCTION ("function not supported"). Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* KVM: PPC: Book3S: Move prototypes for KVM functions into kvm_ppc.hPaul Mackerras2016-12-011-1/+0Star
| | | | | | | | | | | | This moves the prototypes for functions that are only called from assembler code out of asm/asm-prototypes.h into asm/kvm_ppc.h. The prototypes were added in commit ebe4535fbe7a ("KVM: PPC: Book3S HV: sparse: prototypes for functions called from assembler", 2016-10-10), but given that the functions are KVM functions, having them in a KVM header will be better for long-term maintenance. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Adapt TLB invalidations to work on POWER9Paul Mackerras2016-11-231-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | POWER9 adds new capabilities to the tlbie (TLB invalidate entry) and tlbiel (local tlbie) instructions. Both instructions get a set of new parameters (RIC, PRS and R) which appear as bits in the instruction word. The tlbiel instruction now has a second register operand, which contains a PID and/or LPID value if needed, and should otherwise contain 0. This adapts KVM-HV's usage of tlbie and tlbiel to work on POWER9 as well as older processors. Since we only handle HPT guests so far, we need RIC=0 PRS=0 R=0, which ends up with the same instruction word as on previous processors, so we don't need to conditionally execute different instructions depending on the processor. The local flush on first entry to a guest in book3s_hv_rmhandlers.S is a loop which depends on the number of TLB sets. Rather than using feature sections to set the number of iterations based on which CPU we're on, we now work out this number at VM creation time and store it in the kvm_arch struct. That will make it possible to get the number from the device tree in future, which will help with compatibility with future processors. Since mmu_partition_table_set_entry() does a global flush of the whole LPID, we don't need to do the TLB flush on first entry to the guest on each processor. Therefore we don't set all bits in the tlb_need_flush bitmap on VM startup on POWER9. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Adapt to new HPTE format on POWER9Paul Mackerras2016-11-231-31/+70
| | | | | | | | | | | | | This adapts the KVM-HV hashed page table (HPT) code to read and write HPT entries in the new format defined in Power ISA v3.00 on POWER9 machines. The new format moves the B (segment size) field from the first doubleword to the second, and trims some bits from the AVA (abbreviated virtual address) and ARPN (abbreviated real page number) fields. As far as possible, the conversion is done when reading or writing the HPT entries, and the rest of the code continues to use the old format. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Don't lose hardware R/C bit updates in H_PROTECTPaul Mackerras2016-11-211-0/+2
| | | | | | | | | | | | | | | | | | | | | | | The hashed page table MMU in POWER processors can update the R (reference) and C (change) bits in a HPTE at any time until the HPTE has been invalidated and the TLB invalidation sequence has completed. In kvmppc_h_protect, which implements the H_PROTECT hypercall, we read the HPTE, modify the second doubleword, invalidate the HPTE in memory, do the TLB invalidation sequence, and then write the modified value of the second doubleword back to memory. In doing so we could overwrite an R/C bit update done by hardware between when we read the HPTE and when the TLB invalidation completed. To fix this we re-read the second doubleword after the TLB invalidation and OR in the (possibly) new values of R and C. We can use an OR since hardware only ever sets R and C, never clears them. This race was found by code inspection. In principle this bug could cause occasional guest memory corruption under host memory pressure. Fixes: a8606e20e41a ("KVM: PPC: Handle some PAPR hcalls in the kernel", 2011-06-29) Cc: stable@vger.kernel.org # v3.19+ Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Add a per vcpu cache for recently page faulted MMIO entriesYongji Xie2016-11-211-19/+98
| | | | | | | | | | | | | | | | | | | | | | | This keeps a per vcpu cache for recently page faulted MMIO entries. On a page fault, if the entry exists in the cache, we can avoid some time-consuming paths, for example, looking up HPT, locking HPTE twice and searching mmio gfn from memslots, then directly call kvmppc_hv_emulate_mmio(). In current implenment, we limit the size of cache to four. We think it's enough to cover the high-frequency MMIO HPTEs in most case. For example, considering the case of using virtio device, for virtio legacy devices, one HPTE could handle notifications from up to 1024 (64K page / 64 byte Port IO register) devices, so one cache entry is enough; for virtio modern devices, we always need one HPTE to handle notification for each device because modern device would use a 8M MMIO register to notify host instead of Port IO register, typically the system's configuration should not exceed four virtio devices per vcpu, four cache entry is also enough in this case. Of course, if needed, we could also modify the macro to a module parameter in the future. Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: Clear the key field of HPTE when the page is paged outYongji Xie2016-11-211-1/+4
| | | | | | | | | | | | | Currently we mark a HPTE for emulated MMIO with HPTE_V_ABSENT bit set as well as key 0x1f. However, those HPTEs may be conflicted with the HPTE for real guest RAM page HPTE with key 0x1f when the page get paged out. This patch clears the key field of HPTE when the page is paged out, then recover it when HPTE is re-established. Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* KVM: PPC: Book3S HV: sparse: prototypes for functions called from assemblerDaniel Axtens2016-11-211-0/+1
| | | | | | | | | A bunch of KVM functions are only called from assembler. Give them prototypes in asm-prototypes.h This reduces sparse warnings. Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* powerpc/mm: Drop WIMG in favour of new constantsAneesh Kumar K.V2016-05-011-6/+6
| | | | | | | | | | | | | | | | | | | | | | PowerISA 3.0 introduces two pte bits with the below meaning for radix: 00 -> Normal Memory 01 -> Strong Access Order (SAO) 10 -> Non idempotent I/O (Cache inhibited and guarded) 11 -> Tolerant I/O (Cache inhibited) We drop the existing WIMG bits in the Linux page table in favour of the above constants. We loose _PAGE_WRITETHRU with this conversion. We only use writethru via pgprot_cached_wthru() which is used by fbdev/controlfb.c which is Apple control display and also PPC32. With respect to _PAGE_COHERENCE, we have been marking hpte always coherent for some time now. htab_convert_pte_flags() always added HPTE_R_M. NOTE: KVM changes need closer review. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc/mm: Move hash related mmu-*.h headers to book3s/Aneesh Kumar K.V2016-03-031-1/+1
| | | | | | | No code changes. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.4-1' of ↵Linus Torvalds2015-11-061-3/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * powerpc/mm: Differentiate between hugetlb and THP during page walkAneesh Kumar K.V2015-10-121-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | KVM: PPC: Book3S HV: Make H_REMOVE return correct HPTE value for absent HPTEsPaul Mackerras2015-10-211-0/+2
|/ | | | | | | | | | This fixes a bug where the old HPTE value returned by H_REMOVE has the valid bit clear if the HPTE was an absent HPTE, as happens for HPTEs for emulated MMIO pages and for RAM pages that have been paged out by the host. If the absent bit is set, we clear it and set the valid bit, because from the guest's point of view, the HPTE is valid. Signed-off-by: Paul Mackerras <paulus@samba.org>
* KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MODPaul Mackerras2015-08-221-7/+119
| | | | | | | | | | | | | | | | | | This adds implementations for the H_CLEAR_REF (test and clear reference bit) and H_CLEAR_MOD (test and clear changed bit) hypercalls. When clearing the reference or change bit in the guest view of the HPTE, we also have to clear it in the real HPTE so that we can detect future references or changes. When we do so, we transfer the R or C bit value to the rmap entry for the underlying host page so that kvm_age_hva_hv(), kvm_test_age_hva_hv() and kvmppc_hv_get_dirty_log() know that the page has been referenced and/or changed. These hypercalls are not used by Linux guests. These implementations have been tested using a FreeBSD guest. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Fix bug in dirty page trackingPaul Mackerras2015-08-221-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a bug in the tracking of pages that get modified by the guest. If the guest creates a large-page HPTE, writes to memory somewhere within the large page, and then removes the HPTE, we only record the modified state for the first normal page within the large page, when in fact the guest might have modified some other normal page within the large page. To fix this we use some unused bits in the rmap entry to record the order (log base 2) of the size of the page that was modified, when removing an HPTE. Then in kvm_test_clear_dirty_npages() we use that order to return the correct number of modified pages. The same thing could in principle happen when removing a HPTE at the host's request, i.e. when paging out a page, except that we never page out large pages, and the guest can only create large-page HPTEs if the guest RAM is backed by large pages. However, we also fix this case for the sake of future-proofing. The reference bit is also subject to the same loss of information. We don't make the same fix here for the reference bit because there isn't an interface for userspace to find out which pages the guest has referenced, whereas there is one for userspace to find out which pages the guest has modified. Because of this loss of information, the kvm_age_hva_hv() and kvm_test_age_hva_hv() functions might incorrectly say that a page has not been referenced when it has, but that doesn't matter greatly because we never page or swap out large pages. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Fix race in reading change bit when removing HPTEPaul Mackerras2015-08-221-6/+12
| | | | | | | | | | | | | | | | | | | | | The reference (R) and change (C) bits in a HPT entry can be set by hardware at any time up until the HPTE is invalidated and the TLB invalidation sequence has completed. This means that when removing a HPTE, we need to read the HPTE after the invalidation sequence has completed in order to obtain reliable values of R and C. The code in kvmppc_do_h_remove() used to do this. However, commit 6f22bd3265fb ("KVM: PPC: Book3S HV: Make HTAB code LE host aware") removed the read after invalidation as a side effect of other changes. This restores the read of the HPTE after invalidation. The user-visible effect of this bug would be that when migrating a guest, there is a small probability that a page modified by the guest and then unmapped by the guest might not get re-transmitted and thus the destination might end up with a stale copy of the page. Fixes: 6f22bd3265fb Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* Merge tag 'powerpc-4.1-2' of ↵Linus Torvalds2015-04-261-39/+47
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux Pull powerpc fixes from Michael Ellerman: - fix for mm_dec_nr_pmds() from Scott. - fixes for oopses seen with KVM + THP from Aneesh. - build fixes from Aneesh & Shreyas. * tag 'powerpc-4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/mm: Fix build error with CONFIG_PPC_TRANSACTIONAL_MEM disabled powerpc/kvm: Fix ppc64_defconfig + PPC_POWERNV=n build error powerpc/mm/thp: Return pte address if we find trans_splitting. powerpc/mm/thp: Make page table walk safe against thp split/collapse KVM: PPC: Remove page table walk helpers KVM: PPC: Use READ_ONCE when dereferencing pte_t pointer powerpc/hugetlb: Call mm_dec_nr_pmds() in hugetlb_free_pmd_range()
| * powerpc/mm/thp: Return pte address if we find trans_splitting.Aneesh Kumar K.V2015-04-171-1/+1
| | | | | | | | | | | | | | | | | | | | For THP that is marked trans splitting, we return the pte. This require the callers to handle the pmd_trans_splitting scenario, if they care. All the current callers are either looking at pfn or write_ok, hence we don't need to update them. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * powerpc/mm/thp: Make page table walk safe against thp split/collapseAneesh Kumar K.V2015-04-171-7/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can disable a THP split or a hugepage collapse by disabling irq. We do send IPI to all the cpus in the early part of split/collapse, and disabling local irq ensure we don't make progress with split/collapse. If the THP is getting split we return NULL from find_linux_pte_or_hugepte(). For all the current callers it should be ok. We need to be careful if we want to use returned pte_t pointer outside the irq disabled region. W.r.t to THP split, the pfn remains the same, but then a hugepage collapse will result in a pfn change. There are few steps we can take to avoid a hugepage collapse.One way is to take page reference inside the irq disable region. Other option is to take mmap_sem so that a parallel collapse will not happen. We can also disable collapse by taking pmd_lock. Another method used by kvm subsystem is to check whether we had a mmu_notifer update in between using mmu_notifier_retry(). Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * KVM: PPC: Remove page table walk helpersAneesh Kumar K.V2015-04-171-35/+27Star
| | | | | | | | | | | | | | | | | | This patch remove helpers which we had used only once in the code. Limiting page table walk variants help in ensuring that we won't end up with code walking page table with wrong assumptions. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | KVM: PPC: Book3S HV: Add helpers for lock/unlock hpteAneesh Kumar K.V2015-04-211-16/+9Star
|/ | | | | | | | | | This adds helper routines for locking and unlocking HPTEs, and uses them in the rest of the code. We don't change any locking rules in this patch. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* mm: convert p[te|md]_numa users to p[te|md]_protnone_numaMel Gorman2015-02-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | Convert existing users of pte_numa and friends to the new helper. Note that the kernel is broken after this patch is applied until the other page table modifiers are also altered. This patch layout is to make review easier. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Tested-by: Sasha Levin <sasha.levin@oracle.com> Cc: Dave Jones <davej@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* KVM: PPC: Book3S HV: Remove code for PPC970 processorsPaul Mackerras2014-12-171-93/+17Star
| | | | | | | | | | | | | | | | | This removes the code that was added to enable HV KVM to work on PPC970 processors. The PPC970 is an old CPU that doesn't support virtualizing guest memory. Removing PPC970 support also lets us remove the code for allocating and managing contiguous real-mode areas, the code for the !kvm->arch.using_mmu_notifiers case, the code for pinning pages of guest memory when first accessed and keeping track of which pages have been pinned, and the code for handling H_ENTER hypercalls in virtual mode. Book3S HV KVM is now supported only on POWER7 and POWER8 processors. The KVM_CAP_PPC_RMA capability now always returns 0. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Fix KSM memory corruptionPaul Mackerras2014-12-151-27/+17Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Testing with KSM active in the host showed occasional corruption of guest memory. Typically a page that should have contained zeroes would contain values that look like the contents of a user process stack (values such as 0x0000_3fff_xxxx_xxx). Code inspection in kvmppc_h_protect revealed that there was a race condition with the possibility of granting write access to a page which is read-only in the host page tables. The code attempts to keep the host mapping read-only if the host userspace PTE is read-only, but if that PTE had been temporarily made invalid for any reason, the read-only check would not trigger and the host HPTE could end up read-write. Examination of the guest HPT in the failure situation revealed that there were indeed shared pages which should have been read-only that were mapped read-write. To close this race, we don't let a page go from being read-only to being read-write, as far as the real HPTE mapping the page is concerned (the guest view can go to read-write, but the actual mapping stays read-only). When the guest tries to write to the page, we take an HDSI and let kvmppc_book3s_hv_page_fault take care of providing a writable HPTE for the page. This eliminates the occasional corruption of shared pages that was previously seen with KSM active. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvmPaolo Bonzini2014-08-051-63/+83
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch queue for ppc - 2014-08-01 Highlights in this release include: - BookE: Rework instruction fetch, not racy anymore now - BookE HV: Fix ONE_REG accessors for some in-hardware registers - Book3S: Good number of LE host fixes, enable HV on LE - Book3S: Some misc bug fixes - Book3S HV: Add in-guest debug support - Book3S HV: Preload cache lines on context switch - Remove 440 support Alexander Graf (31): KVM: PPC: Book3s PR: Disable AIL mode with OPAL KVM: PPC: Book3s HV: Fix tlbie compile error KVM: PPC: Book3S PR: Handle hyp doorbell exits KVM: PPC: Book3S PR: Fix ABIv2 on LE KVM: PPC: Book3S PR: Fix sparse endian checks PPC: Add asm helpers for BE 32bit load/store KVM: PPC: Book3S HV: Make HTAB code LE host aware KVM: PPC: Book3S HV: Access guest VPA in BE KVM: PPC: Book3S HV: Access host lppaca and shadow slb in BE KVM: PPC: Book3S HV: Access XICS in BE KVM: PPC: Book3S HV: Fix ABIv2 on LE KVM: PPC: Book3S HV: Enable for little endian hosts KVM: PPC: Book3S: Move vcore definition to end of kvm_arch struct KVM: PPC: Deflect page write faults properly in kvmppc_st KVM: PPC: Book3S: Stop PTE lookup on write errors KVM: PPC: Book3S: Add hack for split real mode KVM: PPC: Book3S: Make magic page properly 4k mappable KVM: PPC: Remove 440 support KVM: Rename and add argument to check_extension KVM: Allow KVM_CHECK_EXTENSION on the vm fd KVM: PPC: Book3S: Provide different CAPs based on HV or PR mode KVM: PPC: Implement kvmppc_xlate for all targets KVM: PPC: Move kvmppc_ld/st to common code KVM: PPC: Remove kvmppc_bad_hva() KVM: PPC: Use kvm_read_guest in kvmppc_ld KVM: PPC: Handle magic page in kvmppc_ld/st KVM: PPC: Separate loadstore emulation from priv emulation KVM: PPC: Expose helper functions for data/inst faults KVM: PPC: Remove DCR handling KVM: PPC: HV: Remove generic instruction emulation KVM: PPC: PR: Handle FSCR feature deselects Alexey Kardashevskiy (1): KVM: PPC: Book3S: Fix LPCR one_reg interface Aneesh Kumar K.V (4): KVM: PPC: BOOK3S: PR: Fix PURR and SPURR emulation KVM: PPC: BOOK3S: PR: Emulate virtual timebase register KVM: PPC: BOOK3S: PR: Emulate instruction counter KVM: PPC: BOOK3S: HV: Update compute_tlbie_rb to handle 16MB base page Anton Blanchard (2): KVM: PPC: Book3S HV: Fix ABIv2 indirect branch issue KVM: PPC: Assembly functions exported to modules need _GLOBAL_TOC() Bharat Bhushan (10): kvm: ppc: bookehv: Added wrapper macros for shadow registers kvm: ppc: booke: Use the shared struct helpers of SRR0 and SRR1 kvm: ppc: booke: Use the shared struct helpers of SPRN_DEAR kvm: ppc: booke: Add shared struct helpers of SPRN_ESR kvm: ppc: booke: Use the shared struct helpers for SPRN_SPRG0-7 kvm: ppc: Add SPRN_EPR get helper function kvm: ppc: bookehv: Save restore SPRN_SPRG9 on guest entry exit KVM: PPC: Booke-hv: Add one reg interface for SPRG9 KVM: PPC: Remove comment saying SPRG1 is used for vcpu pointer KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr Michael Neuling (1): KVM: PPC: Book3S HV: Add H_SET_MODE hcall handling Mihai Caraman (8): KVM: PPC: e500mc: Enhance tlb invalidation condition on vcpu schedule KVM: PPC: e500: Fix default tlb for victim hint KVM: PPC: e500: Emulate power management control SPR KVM: PPC: e500mc: Revert "add load inst fixup" KVM: PPC: Book3e: Add TLBSEL/TSIZE defines for MAS0/1 KVM: PPC: Book3s: Remove kvmppc_read_inst() function KVM: PPC: Allow kvmppc_get_last_inst() to fail KVM: PPC: Bookehv: Get vcpu's last instruction for emulation Paul Mackerras (4): KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handling KVM: PPC: Book3S: Allow only implemented hcalls to be enabled or disabled KVM: PPC: Book3S PR: Take SRCU read lock around RTAS kvm_read_guest() call KVM: PPC: Book3S: Make kvmppc_ld return a more accurate error indication Stewart Smith (2): Split out struct kvmppc_vcore creation to separate function Use the POWER8 Micro Partition Prefetch Engine in KVM HV on POWER8 Conflicts: Documentation/virtual/kvm/api.txt
| * KVM: PPC: Book3S HV: Make HTAB code LE host awareAlexander Graf2014-07-281-63/+83
| | | | | | | | | | | | | | | | | | | | When running on an LE host all data structures are kept in little endian byte order. However, the HTAB still needs to be maintained in big endian. So every time we access any HTAB we need to make sure we do so in the right byte order. Fix up all accesses to manually byte swap. Signed-off-by: Alexander Graf <agraf@suse.de>
* | KVM: PPC: BOOK3S: HV: Use base page size when comparing against slb valueAneesh Kumar K.V2014-06-251-5/+2Star
|/ | | | | | | | | | | With guests supporting Multiple page size per segment (MPSS), hpte_page_size returns the actual page size used. Add a new function to return base page size and use that to compare against the the page size calculated from SLB. Without this patch a hpte lookup can fail since we are comparing wrong page size in kvmppc_hv_find_lock_hpte. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Alexander Graf <agraf@suse.de>
* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm into nextLinus Torvalds2014-06-041-1/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "At over 200 commits, covering almost all supported architectures, this was a pretty active cycle for KVM. Changes include: - a lot of s390 changes: optimizations, support for migration, GDB support and more - ARM changes are pretty small: support for the PSCI 0.2 hypercall interface on both the guest and the host (the latter acked by Catalin) - initial POWER8 and little-endian host support - support for running u-boot on embedded POWER targets - pretty large changes to MIPS too, completing the userspace interface and improving the handling of virtualized timer hardware - for x86, a larger set of changes is scheduled for 3.17. Still, we have a few emulator bugfixes and support for running nested fully-virtualized Xen guests (para-virtualized Xen guests have always worked). And some optimizations too. The only missing architecture here is ia64. It's not a coincidence that support for KVM on ia64 is scheduled for removal in 3.17" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (203 commits) KVM: add missing cleanup_srcu_struct KVM: PPC: Book3S PR: Rework SLB switching code KVM: PPC: Book3S PR: Use SLB entry 0 KVM: PPC: Book3S HV: Fix machine check delivery to guest KVM: PPC: Book3S HV: Work around POWER8 performance monitor bugs KVM: PPC: Book3S HV: Make sure we don't miss dirty pages KVM: PPC: Book3S HV: Fix dirty map for hugepages KVM: PPC: Book3S HV: Put huge-page HPTEs in rmap chain for base address KVM: PPC: Book3S HV: Fix check for running inside guest in global_invalidates() KVM: PPC: Book3S: Move KVM_REG_PPC_WORT to an unused register number KVM: PPC: Book3S: Add ONE_REG register names that were missed KVM: PPC: Add CAP to indicate hcall fixes KVM: PPC: MPIC: Reset IRQ source private members KVM: PPC: Graciously fail broken LE hypercalls PPC: ePAPR: Fix hypercall on LE guest KVM: PPC: BOOK3S: Remove open coded make_dsisr in alignment handler KVM: PPC: BOOK3S: Always use the saved DAR value PPC: KVM: Make NX bit available with magic page KVM: PPC: Disable NX for old magic page using guests KVM: PPC: BOOK3S: HV: Add mixed page-size support for guest ...
| * KVM: PPC: Book3S HV: Fix check for running inside guest in global_invalidates()Paul Mackerras2014-05-301-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The global_invalidates() function contains a check that is intended to tell whether we are currently executing in the context of a hypercall issued by the guest. The reason is that the optimization of using a local TLB invalidate instruction is only valid in that context. The check was testing local_paca->kvm_hstate.kvm_vcore, which gets set when entering the guest but no longer gets cleared when exiting the guest. To fix this, we use the kvm_vcpu field instead, which does get cleared when exiting the guest, by the kvmppc_release_hwthread() calls inside kvmppc_run_core(). The effect of having the check wrong was that when kvmppc_do_h_remove() got called from htab_write() on the destination machine during a migration, it cleared the current cpu's bit in kvm->arch.need_tlb_flush. This meant that when the guest started running in the destination VM, it may miss out on doing a complete TLB flush, and therefore may end up using stale TLB entries from a previous guest that used the same LPID value. This should make migration more reliable. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* | KVM: PPC: Book3S: HV: make _PAGE_NUMA take effectpingfank@linux.vnet.ibm.com2014-04-281-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | Numa fault is a method which help to achieve auto numa balancing. When such a page fault takes place, the page fault handler will check whether the page is placed correctly. If not, migration should be involved to cut down the distance between the cpu and pages. A pte with _PAGE_NUMA help to implement numa fault. It means not to allow the MMU to access the page directly. So a page fault is triggered and numa fault handler gets the opportunity to run checker. As for the access of MMU, we need special handling for the powernv's guest. When we mark a pte with _PAGE_NUMA, we already call mmu_notifier to invalidate it in guest's htab, but when we tried to re-insert them, we firstly try to map it in real-mode. Only after this fails, we fallback to virt mode, and most of important, we run numa fault handler in virt mode. This patch guards the way of real-mode to ensure that if a pte is marked with _PAGE_NUMA, it will NOT be mapped in real mode, instead, it will be mapped in virt mode and have the opportunity to be checked with placement. Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Don't use kvm_memslots() in real modePaul Mackerras2014-03-291-3/+3
| | | | | | | | | | | | | | | | | | | | | | With HV KVM, some high-frequency hypercalls such as H_ENTER are handled in real mode, and need to access the memslots array for the guest. Accessing the memslots array is safe, because we hold the SRCU read lock for the whole time that a guest vcpu is running. However, the checks that kvm_memslots() does when lockdep is enabled are potentially unsafe in real mode, when only the linear mapping is available. Furthermore, kvm_memslots() can be called from a secondary CPU thread, which is an offline CPU from the point of view of the host kernel, and is not running the task which holds the SRCU read lock. To avoid false positives in the checks in kvm_memslots(), and to avoid possible side effects from doing the checks in real mode, this replaces kvm_memslots() with kvm_memslots_raw() in all the places that execute in real mode. kvm_memslots_raw() is a new function that is like kvm_memslots() but uses rcu_dereference_raw_notrace() instead of kvm_dereference_check(). Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: Scott Wood <scottwood@freescale.com>
* Merge branch 'kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-queuePaolo Bonzini2014-01-291-3/+5
|\ | | | | | | | | | | Conflicts: arch/powerpc/kvm/book3s_hv_rmhandlers.S arch/powerpc/kvm/booke.c
| * kvm: book3s: rename lookup_linux_pte() to lookup_linux_pte_and_update()Bharat Bhushan2014-01-091-3/+5
| | | | | | | | | | | | | | | | | | lookup_linux_pte() is doing more than lookup, updating the pte, so for clarity it is renamed to lookup_linux_pte_and_update() Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> Reviewed-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
* | KVM: PPC: Book3S HV: Don't drop low-order page address bitsPaul Mackerras2013-12-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit caaa4c804fae ("KVM: PPC: Book3S HV: Fix physical address calculations") unfortunately resulted in some low-order address bits getting dropped in the case where the guest is creating a 4k HPTE and the host page size is 64k. By getting the low-order bits from hva rather than gpa we miss out on bits 12 - 15 in this case, since hva is at page granularity. This puts the missing bits back in. Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* | powerpc: kvm: fix rare but potential deadlock scenepingfan liu2013-11-181-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since kvmppc_hv_find_lock_hpte() is called from both virtmode and realmode, so it can trigger the deadlock. Suppose the following scene: Two physical cpuM, cpuN, two VM instances A, B, each VM has a group of vcpus. If on cpuM, vcpu_A_1 holds bitlock X (HPTE_V_HVLOCK), then is switched out, and on cpuN, vcpu_A_2 try to lock X in realmode, then cpuN will be caught in realmode for a long time. What makes things even worse if the following happens, On cpuM, bitlockX is hold, on cpuN, Y is hold. vcpu_B_2 try to lock Y on cpuM in realmode vcpu_A_2 try to lock X on cpuN in realmode Oops! deadlock happens Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com> Reviewed-by: Paul Mackerras <paulus@samba.org> CC: stable@vger.kernel.org Signed-off-by: Alexander Graf <agraf@suse.de>
* | KVM: PPC: Book3S HV: Fix physical address calculationsPaul Mackerras2013-11-181-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a bug in kvmppc_do_h_enter() where the physical address for a page can be calculated incorrectly if transparent huge pages (THP) are active. Until THP came along, it was true that if we encountered a large (16M) page in kvmppc_do_h_enter(), then the associated memslot must be 16M aligned for both its guest physical address and the userspace address, and the physical address calculations in kvmppc_do_h_enter() assumed that. With THP, that is no longer true. In the case where we are using MMU notifiers and the page size that we get from the Linux page tables is larger than the page being mapped by the guest, we need to fill in some low-order bits of the physical address. Without THP, these bits would be the same in the guest physical address (gpa) and the host virtual address (hva). With THP, they can be different, and we need to use the bits from hva rather than gpa. In the case where we are not using MMU notifiers, the host physical address we get from the memslot->arch.slot_phys[] array already includes the low-order bits down to the PAGE_SIZE level, even if we are using large pages. Thus we can simplify the calculation in this case to just add in the remaining bits in the case where PAGE_SIZE is 64k and the guest is mapping a 4k page. The same bug exists in kvmppc_book3s_hv_page_fault(). The basic fix is to use psize (the page size from the HPTE) rather than pte_size (the page size from the Linux PTE) when updating the HPTE low word in r. That means that pfn needs to be computed to PAGE_SIZE granularity even if the Linux PTE is a huge page PTE. That can be arranged simply by doing the page_to_pfn() before setting page to the head of the compound page. If psize is less than PAGE_SIZE, then we need to make sure we only update the bits from PAGE_SIZE upwards, in order not to lose any sub-page offset bits in r. On the other hand, if psize is greater than PAGE_SIZE, we need to make sure we don't bring in non-zero low order bits in pfn, hence we mask (pfn << PAGE_SHIFT) with ~(psize - 1). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* Merge branch 'next' of ↵Linus Torvalds2013-09-061-0/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc updates from Ben Herrenschmidt: "Here's the powerpc batch for this merge window. Some of the highlights are: - A bunch of endian fixes ! We don't have full LE support yet in that release but this contains a lot of fixes all over arch/powerpc to use the proper accessors, call the firmware with the right endian mode, etc... - A few updates to our "powernv" platform (non-virtualized, the one to run KVM on), among other, support for bridging the P8 LPC bus for UARTs, support and some EEH fixes. - Some mpc51xx clock API cleanups in preparation for a clock API overhaul - A pile of cleanups of our old math emulation code, including better support for using it to emulate optional FP instructions on embedded chips that otherwise have a HW FPU. - Some infrastructure in selftest, for powerpc now, but could be generalized, initially used by some tests for our perf instruction counting code. - A pile of fixes for hotplug on pseries (that was seriously bitrotting) - The usual slew of freescale embedded updates, new boards, 64-bit hiberation support, e6500 core PMU support, etc..." * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (146 commits) powerpc: Correct FSCR bit definitions powerpc/xmon: Fix printing of set of CPUs in xmon powerpc/pseries: Move lparcfg.c to platforms/pseries powerpc/powernv: Return secondary CPUs to firmware on kexec powerpc/btext: Fix CONFIG_PPC_EARLY_DEBUG_BOOTX on ppc32 powerpc: Cleanup handling of the DSCR bit in the FSCR register powerpc/pseries: Child nodes are not detached by dlpar_detach_node powerpc/pseries: Add mising of_node_put in delete_dt_node powerpc/pseries: Make dlpar_configure_connector parent node aware powerpc/pseries: Do all node initialization in dlpar_parse_cc_node powerpc/pseries: Fix parsing of initial node path in update_dt_node powerpc/pseries: Pack update_props_workarea to map correctly to rtas buffer header powerpc/pseries: Fix over writing of rtas return code in update_dt_node powerpc/pseries: Fix creation of loop in device node property list powerpc: Skip emulating & leave interrupts off for kernel program checks powerpc: Add more exception trampolines for hypervisor exceptions powerpc: Fix location and rename exception trampolines powerpc: Add more trap names to xmon powerpc/pseries: Add a warning in the case of cross-cpu VPA registration powerpc: Update the 00-Index in Documentation/powerpc ...
| * powerpc: Make rwlocks endian safeAnton Blanchard2013-08-141-0/+4
| | | | | | | | | | | | | | | | | | Our ppc64 spinlocks and rwlocks use a trick where a lock token and the paca index are placed in the lock with a single store. Since we are using two u16s they need adjusting for little endian. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | Merge remote-tracking branch 'origin/next' into kvm-ppc-nextAlexander Graf2013-08-291-8/+6Star
|\| | | | | | | | | | | | | Conflicts: mm/Kconfig CMA DMA split and ZSWAP introduction were conflicting, fix up manually.
| * powerpc/kvm: Handle transparent hugepage in KVMAneesh Kumar K.V2013-06-211-7/+5Star
| | | | | | | | | | | | | | | | We can find pte that are splitting while walking page tables. Return None pte in that case. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * powerpc: Replace find_linux_pte with find_linux_pte_or_hugepteAneesh Kumar K.V2013-06-211-1/+1
| | | | | | | | | | | | | | | | Replace find_linux_pte with find_linux_pte_or_hugepte and explicitly document why we don't need to handle transparent hugepages at callsites. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | KVM: PPC: Book3S HV: Correct tlbie usagePaul Mackerras2013-07-101-58/+81
|/ | | | | | | | | | | | | | | | | | | | | | | This corrects the usage of the tlbie (TLB invalidate entry) instruction in HV KVM. The tlbie instruction changed between PPC970 and POWER7. On the PPC970, the bit to select large vs. small page is in the instruction, not in the RB register value. This changes the code to use the correct form on PPC970. On POWER7 we were calculating the AVAL (Abbreviated Virtual Address, Lower) field of the RB value incorrectly for 64k pages. This fixes it. Since we now have several cases to handle for the tlbie instruction, this factors out the code to do a sequence of tlbies into a new function, do_tlbies(), and calls that from the various places where the code was doing tlbie instructions inline. It also makes kvmppc_h_bulk_remove() use the same global_invalidates() function for determining whether to do local or global TLB invalidations as is used in other places, for consistency, and also to make sure that kvm->arch.need_tlb_flush gets updated properly. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Make HPT reading code notice R/C bit changesPaul Mackerras2013-04-261-11/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | At present, the code that determines whether a HPT entry has changed, and thus needs to be sent to userspace when it is copying the HPT, doesn't consider a hardware update to the reference and change bits (R and C) in the HPT entries to constitute a change that needs to be sent to userspace. This adds code to check for changes in R and C when we are scanning the HPT to find changed entries, and adds code to set the changed flag for the HPTE when we update the R and C bits in the guest view of the HPTE. Since we now need to set the HPTE changed flag in book3s_64_mmu_hv.c as well as book3s_hv_rm_mmu.c, we move the note_hpte_modification() function into kvm_book3s_64.h. Current Linux guest kernels don't use the hardware updates of R and C in the HPT, so this change won't affect them. Linux (or other) kernels might in future want to use the R and C bits and have them correctly transferred across when a guest is migrated, so it is better to correct this deficiency. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Improve handling of local vs. global TLB invalidationsPaul Mackerras2012-12-061-4/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we change or remove a HPT (hashed page table) entry, we can do either a global TLB invalidation (tlbie) that works across the whole machine, or a local invalidation (tlbiel) that only affects this core. Currently we do local invalidations if the VM has only one vcpu or if the guest requests it with the H_LOCAL flag, though the guest Linux kernel currently doesn't ever use H_LOCAL. Then, to cope with the possibility that vcpus moving around to different physical cores might expose stale TLB entries, there is some code in kvmppc_hv_entry to flush the whole TLB of entries for this VM if either this vcpu is now running on a different physical core from where it last ran, or if this physical core last ran a different vcpu. There are a number of problems on POWER7 with this as it stands: - The TLB invalidation is done per thread, whereas it only needs to be done per core, since the TLB is shared between the threads. - With the possibility of the host paging out guest pages, the use of H_LOCAL by an SMP guest is dangerous since the guest could possibly retain and use a stale TLB entry pointing to a page that had been removed from the guest. - The TLB invalidations that we do when a vcpu moves from one physical core to another are unnecessary in the case of an SMP guest that isn't using H_LOCAL. - The optimization of using local invalidations rather than global should apply to guests with one virtual core, not just one vcpu. (None of this applies on PPC970, since there we always have to invalidate the whole TLB when entering and leaving the guest, and we can't support paging out guest memory.) To fix these problems and simplify the code, we now maintain a simple cpumask of which cpus need to flush the TLB on entry to the guest. (This is indexed by cpu, though we only ever use the bits for thread 0 of each core.) Whenever we do a local TLB invalidation, we set the bits for every cpu except the bit for thread 0 of the core that we're currently running on. Whenever we enter a guest, we test and clear the bit for our core, and flush the TLB if it was set. On initial startup of the VM, and when resetting the HPT, we set all the bits in the need_tlb_flush cpumask, since any core could potentially have stale TLB entries from the previous VM to use the same LPID, or the previous contents of the HPT. Then, we maintain a count of the number of online virtual cores, and use that when deciding whether to use a local invalidation rather than the number of online vcpus. The code to make that decision is extracted out into a new function, global_invalidates(). For multi-core guests on POWER7 (i.e. when we are using mmu notifiers), we now never do local invalidations regardless of the H_LOCAL flag. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Don't give the guest RW access to RO pagesPaul Mackerras2012-12-061-0/+22
| | | | | | | | | | | | | | | | | Currently, if the guest does an H_PROTECT hcall requesting that the permissions on a HPT entry be changed to allow writing, we make the requested change even if the page is marked read-only in the host Linux page tables. This is a problem since it would for instance allow a guest to modify a page that KSM has decided can be shared between multiple guests. To fix this, if the new permissions for the page allow writing, we need to look up the memslot for the page, work out the host virtual address, and look up the Linux page tables to get the PTE for the page. If that PTE is read-only, we reduce the HPTE permissions to read-only. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
* KVM: PPC: Book3S HV: Make a HPTE removal function availablePaul Mackerras2012-12-061-6/+13
| | | | | | | | | This makes a HPTE removal function, kvmppc_do_h_remove(), available outside book3s_hv_rm_mmu.c. This will be used by the HPT writing code. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>