Commit Graph

388 Commits

Author SHA1 Message Date
Linus Torvalds 0c86e761b9 Merge tag 'vfio-v4.20-rc1.v2' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:

 - EDID interfaces for vfio devices supporting display extensions (Gerd
   Hoffmann)

 - Generically select Type-1 IOMMU model support on ARM/ARM64 (Geert
   Uytterhoeven)

 - Quirk for VFs reporting INTx pin (Alex Williamson)

 - Fix error path memory leak in MSI support (Li Qiang)

* tag 'vfio-v4.20-rc1.v2' of git://github.com/awilliam/linux-vfio:
  vfio: add edid support to mbochs sample driver
  vfio: add edid api for display (vgpu) devices.
  drivers/vfio: Allow type-1 IOMMU instantiation with all ARM/ARM64 IOMMUs
  vfio/pci: Mask buggy SR-IOV VF INTx support
  vfio/pci: Fix potential memory leak in vfio_msi_cap_len
2018-10-31 11:01:38 -07:00
Alexey Kardashevskiy 6e301a8e56 KVM: PPC: Optimize clearing TCEs for sparse tables
The powernv platform maintains 2 TCE tables for VFIO - a hardware TCE
table and a table with userspace addresses. These tables are radix trees,
we allocate indirect levels when they are written to. Since
the memory allocation is problematic in real mode, we have 2 accessors
to the entries:
- for virtual mode: it allocates the memory and it is always expected
to return non-NULL;
- fr real mode: it does not allocate and can return NULL.

Also, DMA windows can span to up to 55 bits of the address space and since
we never have this much RAM, such windows are sparse. However currently
the SPAPR TCE IOMMU driver walks through all TCEs to unpin DMA memory.

Since we maintain a userspace addresses table for VFIO which is a mirror
of the hardware table, we can use it to know which parts of the DMA
window have not been mapped and skip these so does this patch.

The bare metal systems do not have this problem as they use a bypass mode
of a PHB which maps RAM directly.

This helps a lot with sparse DMA windows, reducing the shutdown time from
about 3 minutes per 1 billion TCEs to a few seconds for 32GB sparse guest.
Just skipping the last level seems to be good enough.

As non-allocating accessor is used now in virtual mode as well, rename it
from IOMMU_TABLE_USERSPACE_ENTRY_RM (real mode) to _RO (read only).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-20 20:47:02 +11:00
Geert Uytterhoeven cf3f98c7f4 drivers/vfio: Allow type-1 IOMMU instantiation with all ARM/ARM64 IOMMUs
Currently the type-1 IOMMU instantiation depends on "ARM_SMMU ||
ARM_SMMU_V3", while it applies to other ARM/ARM64 platforms with an
IOMMU (e.g. Renesas VMSA-compatible IPMMUs).

Instead of extending the list of IOMMU types on ARM platforms, replace
the list by "ARM || ARM64", like other architectures do.  The feature is
still restricted to ARM/ARM64 platforms with an IOMMU by the dependency
on IOMMU_API.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-09-25 13:01:28 -06:00
Alex Williamson db04264fe9 vfio/pci: Mask buggy SR-IOV VF INTx support
The SR-IOV spec requires that VFs must report zero for the INTx pin
register as VFs are precluded from INTx support.  It's much easier for
the host kernel to understand whether a device is a VF and therefore
whether a non-zero pin register value is bogus than it is to do the
same in userspace.  Override the INTx count for such devices and
virtualize the pin register to provide a consistent view of the device
to the user.

As this is clearly a spec violation, warn about it to support hardware
validation, but also provide a known whitelist as it doesn't do much
good to continue complaining if the hardware vendor doesn't plan to
fix it.

Known devices with this issue: 8086:270c

Tested-by: Gage Eads <gage.eads@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-09-25 13:01:27 -06:00
Li Qiang 30ea32ab19 vfio/pci: Fix potential memory leak in vfio_msi_cap_len
Free allocated vdev->msi_perm in error path.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-09-25 13:01:27 -06:00
Linus Torvalds 5e2d059b52 Merge tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - A fix for a bug in our page table fragment allocator, where a page
     table page could be freed and reallocated for something else while
     still in use, leading to memory corruption etc. The fix reuses
     pt_mm in struct page (x86 only) for a powerpc only refcount.

   - Fixes to our pkey support. Several are user-visible changes, but
     bring us in to line with x86 behaviour and/or fix outright bugs.
     Thanks to Florian Weimer for reporting many of these.

   - A series to improve the hvc driver & related OPAL console code,
     which have been seen to cause hardlockups at times. The hvc driver
     changes in particular have been in linux-next for ~month.

   - Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y.

   - Remove Power8 DD1 and Power9 DD1 support, neither chip should be in
     use anywhere other than as a paper weight.

   - An optimised memcmp implementation using Power7-or-later VMX
     instructions

   - Support for barrier_nospec on some NXP CPUs.

   - Support for flushing the count cache on context switch on some IBM
     CPUs (controlled by firmware), as a Spectre v2 mitigation.

   - A series to enhance the information we print on unhandled signals
     to bring it into line with other arches, including showing the
     offending VMA and dumping the instructions around the fault.

  Thanks to: Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey
  Kardashevskiy, Alexey Spirkov, Alistair Popple, Andrew Donnellan,
  Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Bartosz Golaszewski,
  Benjamin Herrenschmidt, Bharat Bhushan, Bjoern Noetel, Boqun Feng,
  Breno Leitao, Bryant G. Ly, Camelia Groza, Christophe Leroy, Christoph
  Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt, Darren Stevens, Dave
  Young, David Gibson, Diana Craciun, Finn Thain, Florian Weimer,
  Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand,
  Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel
  Stanley, Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh
  Salgaonkar, Markus Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues,
  Michael Hanselmann, Michael Neuling, Michael Schmitz, Mukesh Ojha,
  Murilo Opsfelder Araujo, Nicholas Piggin, Parth Y Shah, Paul
  Mackerras, Paul Menzel, Ram Pai, Randy Dunlap, Rashmica Gupta, Reza
  Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff, Scott Wood,
  Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson, Thiago
  Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat
  Rao, zhong jiang"

* tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (234 commits)
  powerpc/mm/book3s/radix: Add mapping statistics
  powerpc/uaccess: Enable get_user(u64, *p) on 32-bit
  powerpc/mm/hash: Remove unnecessary do { } while(0) loop
  powerpc/64s: move machine check SLB flushing to mm/slb.c
  powerpc/powernv/idle: Fix build error
  powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range
  powerpc/mm: remove warning about ‘type’ being set
  powerpc/32: Include setup.h header file to fix warnings
  powerpc: Move `path` variable inside DEBUG_PROM
  powerpc/powermac: Make some functions static
  powerpc/powermac: Remove variable x that's never read
  cxl: remove a dead branch
  powerpc/powermac: Add missing include of header pmac.h
  powerpc/kexec: Use common error handling code in setup_new_fdt()
  powerpc/xmon: Add address lookup for percpu symbols
  powerpc/mm: remove huge_pte_offset_and_shift() prototype
  powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled
  powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.
  powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements
  powerpc/fadump: handle crash memory ranges array index overflow
  ...
2018-08-17 11:32:50 -07:00
Linus Torvalds b6d6a3076a Merge tag 'vfio-v4.19-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:

 - mark switch fall-through cases (Gustavo A. R. Silva)

 - disable binding SR-IOV enabled PFs (Alex Williamson)

* tag 'vfio-v4.19-rc1' of git://github.com/awilliam/linux-vfio:
  vfio-pci: Disable binding to PFs with SR-IOV enabled
  vfio: Mark expected switch fall-throughs
2018-08-16 10:34:05 -07:00
Linus Torvalds 4e31843f68 Merge tag 'pci-v4.19-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull pci updates from Bjorn Helgaas:

 - Decode AER errors with names similar to "lspci" (Tyler Baicar)

 - Expose AER statistics in sysfs (Rajat Jain)

 - Clear AER status bits selectively based on the type of recovery (Oza
   Pawandeep)

 - Honor "pcie_ports=native" even if HEST sets FIRMWARE_FIRST (Alexandru
   Gagniuc)

 - Don't clear AER status bits if we're using the "Firmware-First"
   strategy where firmware owns the registers (Alexandru Gagniuc)

 - Use sysfs_match_string() to simplify ASPM sysfs parsing (Andy
   Shevchenko)

 - Remove unnecessary includes of <linux/pci-aspm.h> (Bjorn Helgaas)

 - Defer DPC event handling to work queue (Keith Busch)

 - Use threaded IRQ for DPC bottom half (Keith Busch)

 - Print AER status while handling DPC events (Keith Busch)

 - Work around IDT switch ACS Source Validation erratum (James
   Puthukattukaran)

 - Emit diagnostics for all cases of PCIe Link downtraining (Links
   operating slower than they're capable of) (Alexandru Gagniuc)

 - Skip VFs when configuring Max Payload Size (Myron Stowe)

 - Reduce Root Port Max Payload Size if necessary when hot-adding a
   device below it (Myron Stowe)

 - Simplify SHPC existence/permission checks (Bjorn Helgaas)

 - Remove hotplug sample skeleton driver (Lukas Wunner)

 - Convert pciehp to threaded IRQ handling (Lukas Wunner)

 - Improve pciehp tolerance of missed events and initially unstable
   links (Lukas Wunner)

 - Clear spurious pciehp events on resume (Lukas Wunner)

 - Add pciehp runtime PM support, including for Thunderbolt controllers
   (Lukas Wunner)

 - Support interrupts from pciehp bridges in D3hot (Lukas Wunner)

 - Mark fall-through switch cases before enabling -Wimplicit-fallthrough
   (Gustavo A. R. Silva)

 - Move DMA-debug PCI init from arch code to PCI core (Christoph
   Hellwig)

 - Fix pci_request_irq() usage of IRQF_ONESHOT when no handler is
   supplied (Heiner Kallweit)

 - Unify PCI and DMA direction #defines (Shunyong Yang)

 - Add PCI_DEVICE_DATA() macro (Andy Shevchenko)

 - Check for VPD completion before checking for timeout (Bert Kenward)

 - Limit Netronome NFP5000 config space size to work around erratum
   (Jakub Kicinski)

 - Set IRQCHIP_ONESHOT_SAFE for PCI MSI irqchips (Heiner Kallweit)

 - Document ACPI description of PCI host bridges (Bjorn Helgaas)

 - Add "pci=disable_acs_redir=" parameter to disable ACS redirection for
   peer-to-peer DMA support (we don't have the peer-to-peer support yet;
   this is just one piece) (Logan Gunthorpe)

 - Clean up devm_of_pci_get_host_bridge_resources() resource allocation
   (Jan Kiszka)

 - Fixup resizable BARs after suspend/resume (Christian König)

 - Make "pci=earlydump" generic (Sinan Kaya)

 - Fix ROM BAR access routines to stay in bounds and check for signature
   correctly (Rex Zhu)

 - Add DMA alias quirk for Microsemi Switchtec NTB (Doug Meyer)

 - Expand documentation for pci_add_dma_alias() (Logan Gunthorpe)

 - To avoid bus errors, enable PASID only if entire path supports
   End-End TLP prefixes (Sinan Kaya)

 - Unify slot and bus reset functions and remove hotplug knowledge from
   callers (Sinan Kaya)

 - Add Function-Level Reset quirks for Intel and Samsung NVMe devices to
   fix guest reboot issues (Alex Williamson)

 - Add function 1 DMA alias quirk for Marvell 88SS9183 PCIe SSD
   Controller (Bjorn Helgaas)

 - Remove Xilinx AXI-PCIe host bridge arch dependency (Palmer Dabbelt)

 - Remove Aardvark outbound window configuration (Evan Wang)

 - Fix Aardvark bridge window sizing issue (Zachary Zhang)

 - Convert Aardvark to use pci_host_probe() to reduce code duplication
   (Thomas Petazzoni)

 - Correct the Cadence cdns_pcie_writel() signature (Alan Douglas)

 - Add Cadence support for optional generic PHYs (Alan Douglas)

 - Add Cadence power management ops (Alan Douglas)

 - Remove redundant variable from Cadence driver (Colin Ian King)

 - Add Kirin MSI support (Xiaowei Song)

 - Drop unnecessary root_bus_nr setting from exynos, imx6, keystone,
   armada8k, artpec6, designware-plat, histb, qcom, spear13xx (Shawn
   Guo)

 - Move link notification settings from DesignWare core to individual
   drivers (Gustavo Pimentel)

 - Add endpoint library MSI-X interfaces (Gustavo Pimentel)

 - Correct signature of endpoint library IRQ interfaces (Gustavo
   Pimentel)

 - Add DesignWare endpoint library MSI-X callbacks (Gustavo Pimentel)

 - Add endpoint library MSI-X test support (Gustavo Pimentel)

 - Remove unnecessary GFP_ATOMIC from Hyper-V "new child" allocation
   (Jia-Ju Bai)

 - Add more devices to Broadcom PAXC quirk (Ray Jui)

 - Work around corrupted Broadcom PAXC config space to enable SMMU and
   GICv3 ITS (Ray Jui)

 - Disable MSI parsing to work around broken Broadcom PAXC logic in some
   devices (Ray Jui)

 - Hide unconfigured functions to work around a Broadcom PAXC defect
   (Ray Jui)

 - Lower iproc log level to reduce console output during boot (Ray Jui)

 - Fix mobiveil iomem/phys_addr_t type usage (Lorenzo Pieralisi)

 - Fix mobiveil missing include file (Lorenzo Pieralisi)

 - Add mobiveil Kconfig/Makefile support (Lorenzo Pieralisi)

 - Fix mvebu I/O space remapping issues (Thomas Petazzoni)

 - Use generic pci_host_bridge in mvebu instead of ARM-specific API
   (Thomas Petazzoni)

 - Whitelist VMD devices with fast interrupt handlers to avoid sharing
   vectors with slow handlers (Keith Busch)

* tag 'pci-v4.19-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (153 commits)
  PCI/AER: Don't clear AER bits if error handling is Firmware-First
  PCI: Limit config space size for Netronome NFP5000
  PCI/MSI: Set IRQCHIP_ONESHOT_SAFE for PCI-MSI irqchips
  PCI/VPD: Check for VPD access completion before checking for timeout
  PCI: Add PCI_DEVICE_DATA() macro to fully describe device ID entry
  PCI: Match Root Port's MPS to endpoint's MPSS as necessary
  PCI: Skip MPS logic for Virtual Functions (VFs)
  PCI: Add function 1 DMA alias quirk for Marvell 88SS9183
  PCI: Check for PCIe Link downtraining
  PCI: Add ACS Redirect disable quirk for Intel Sunrise Point
  PCI: Add device-specific ACS Redirect disable infrastructure
  PCI: Convert device-specific ACS quirks from NULL termination to ARRAY_SIZE
  PCI: Add "pci=disable_acs_redir=" parameter for peer-to-peer support
  PCI: Allow specifying devices using a base bus and path of devfns
  PCI: Make specifying PCI devices in kernel parameters reusable
  PCI: Hide ACS quirk declarations inside PCI core
  PCI: Delay after FLR of Intel DC P3700 NVMe
  PCI: Disable Samsung SM961/PM961 NVMe before FLR
  PCI: Export pcie_has_flr()
  PCI: mvebu: Drop bogus comment above mvebu_pcie_map_registers()
  ...
2018-08-16 09:21:54 -07:00
Michael Ellerman b3124ec2f9 Merge branch 'fixes' into next
Merge our fixes branch from the 4.18 cycle to resolve some minor
conflicts.
2018-08-13 15:59:06 +10:00
Alex Williamson 0dd0e297f0 vfio-pci: Disable binding to PFs with SR-IOV enabled
We expect to receive PFs with SR-IOV disabled, however some host
drivers leave SR-IOV enabled at unbind.  This puts us in a state where
we can potentially assign both the PF and the VF, leading to both
functionality as well as security concerns due to lack of managing the
SR-IOV state as well as vendor dependent isolation from the PF to VF.
If we were to attempt to actively disable SR-IOV on driver probe, we
risk VF bound drivers blocking, potentially risking live lock
scenarios.  Therefore simply refuse to bind to PFs with SR-IOV enabled
with a warning message indicating the issue.  Users can resolve this
by re-binding to the host driver and disabling SR-IOV before
attempting to use the device with vfio-pci.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-08-06 12:23:19 -06:00
Gustavo A. R. Silva 544c05a60a vfio: Mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-08-06 12:22:54 -06:00
Linus Torvalds ffb48e7924 Merge tag 'powerpc-4.18-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
 "Two regression fixes, one for xmon disassembly formatting and the
  other to fix the E500 build.

  Two commits to fix a potential security issue in the VFIO code under
  obscure circumstances.

  And finally a fix to the Power9 idle code to restore SPRG3, which is
  user visible and used for sched_getcpu().

  Thanks to: Alexey Kardashevskiy, David Gibson. Gautham R. Shenoy,
  James Clarke"

* tag 'powerpc-4.18-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/powernv: Fix save/restore of SPRG3 on entry/exit from stop (idle)
  powerpc/Makefile: Assemble with -me500 when building for E500
  KVM: PPC: Check if IOMMU page is contained in the pinned physical page
  vfio/spapr: Use IOMMU pageshift rather than pagesize
  powerpc/xmon: Fix disassembly since printf changes
2018-07-21 16:46:53 -07:00
Sinan Kaya c6a44ba950 PCI: Rename pci_try_reset_bus() to pci_reset_bus()
Now that the old implementation of pci_reset_bus() is gone, replace
pci_try_reset_bus() with pci_reset_bus().

Compared to the old implementation, new code will fail immmediately with
-EAGAIN if object lock cannot be obtained.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19 18:04:23 -05:00
Sinan Kaya 811c5cb37d PCI: Unify try slot and bus reset API
Drivers are expected to call pci_try_reset_slot() or pci_try_reset_bus() by
querying if a system supports hotplug or not.  A survey showed that most
drivers don't do this and we are leaking hotplug capability to the user.

Hide pci_try_slot_reset() from drivers and embed into pci_try_bus_reset().
Change pci_try_reset_bus() parameter from struct pci_bus to struct pci_dev.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-19 18:04:23 -05:00
Gustavo A. R. Silva 0e714d2778 vfio/pci: Fix potential Spectre v1
info.index can be indirectly controlled by user-space, hence leading
to a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

drivers/vfio/pci/vfio_pci.c:734 vfio_pci_ioctl()
warn: potential spectre issue 'vdev->region'

Fix this by sanitizing info.index before indirectly using it to index
vdev->region

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-07-18 12:57:25 -06:00
Alexey Kardashevskiy 76fa4975f3 KVM: PPC: Check if IOMMU page is contained in the pinned physical page
A VM which has:
 - a DMA capable device passed through to it (eg. network card);
 - running a malicious kernel that ignores H_PUT_TCE failure;
 - capability of using IOMMU pages bigger that physical pages
can create an IOMMU mapping that exposes (for example) 16MB of
the host physical memory to the device when only 64K was allocated to the VM.

The remaining 16MB - 64K will be some other content of host memory, possibly
including pages of the VM, but also pages of host kernel memory, host
programs or other VMs.

The attacking VM does not control the location of the page it can map,
and is only allowed to map as many pages as it has pages of RAM.

We already have a check in drivers/vfio/vfio_iommu_spapr_tce.c that
an IOMMU page is contained in the physical page so the PCI hardware won't
get access to unassigned host memory; however this check is missing in
the KVM fastpath (H_PUT_TCE accelerated code). We were lucky so far and
did not hit this yet as the very first time when the mapping happens
we do not have tbl::it_userspace allocated yet and fall back to
the userspace which in turn calls VFIO IOMMU driver, this fails and
the guest does not retry,

This stores the smallest preregistered page size in the preregistered
region descriptor and changes the mm_iommu_xxx API to check this against
the IOMMU page size.

This calculates maximum page size as a minimum of the natural region
alignment and compound page size. For the page shift this uses the shift
returned by find_linux_pte() which indicates how the page is mapped to
the current userspace - if the page is huge and this is not a zero, then
it is a leaf pte and the page is mapped within the range.

Fixes: 121f80ba68 ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-18 16:17:17 +10:00
Alexey Kardashevskiy 1463edca67 vfio/spapr: Use IOMMU pageshift rather than pagesize
The size is always equal to 1 page so let's use this. Later on this will
be used for other checks which use page shifts to check the granularity
of access.

This should cause no behavioral change.

Cc: stable@vger.kernel.org # v4.12+
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-18 16:17:07 +10:00
Alexey Kardashevskiy a68bd1267b powerpc/powernv/ioda: Allocate indirect TCE levels on demand
At the moment we allocate the entire TCE table, twice (hardware part and
userspace translation cache). This normally works as we normally have
contigous memory and the guest will map entire RAM for 64bit DMA.

However if we have sparse RAM (one example is a memory device), then
we will allocate TCEs which will never be used as the guest only maps
actual memory for DMA. If it is a single level TCE table, there is nothing
we can really do but if it a multilevel table, we can skip allocating
TCEs we know we won't need.

This adds ability to allocate only first level, saving memory.

This changes iommu_table::free() to avoid allocating of an extra level;
iommu_table::set() will do this when needed.

This adds @alloc parameter to iommu_table::exchange() to tell the callback
if it can allocate an extra level; the flag is set to "false" for
the realmode KVM handlers of H_PUT_TCE hcalls and the callback returns
H_TOO_HARD.

This still requires the entire table to be counted in mm::locked_vm.

To be conservative, this only does on-demand allocation when
the usespace cache table is requested which is the case of VFIO.

The example math for a system replicating a powernv setup with NVLink2
in a guest:
16GB RAM mapped at 0x0
128GB GPU RAM window (16GB of actual RAM) mapped at 0x244000000000

the table to cover that all with 64K pages takes:
(((0x244000000000 + 0x2000000000) >> 16)*8)>>20 = 4556MB

If we allocate only necessary TCE levels, we will only need:
(((0x400000000 + 0x400000000) >> 16)*8)>>20 = 4MB (plus some for indirect
levels).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:11 +10:00
Alexey Kardashevskiy 090bad39b2 powerpc/powernv: Add indirect levels to it_userspace
We want to support sparse memory and therefore huge chunks of DMA windows
do not need to be mapped. If a DMA window big enough to require 2 or more
indirect levels, and a DMA window is used to map all RAM (which is
a default case for 64bit window), we can actually save some memory by
not allocation TCE for regions which we are not going to map anyway.

The hardware tables alreary support indirect levels but we also keep
host-physical-to-userspace translation array which is allocated by
vmalloc() and is a flat array which might use quite some memory.

This converts it_userspace from vmalloc'ed array to a multi level table.

As the format becomes platform dependend, this replaces the direct access
to it_usespace with a iommu_table_ops::useraddrptr hook which returns
a pointer to the userspace copy of a TCE; future extension will return
NULL if the level was not allocated.

This should not change non-KVM handling of TCE tables and it_userspace
will not be allocated for non-KVM tables.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:10 +10:00
Alexey Kardashevskiy 00a5c58d94 KVM: PPC: Make iommu_table::it_userspace big endian
We are going to reuse multilevel TCE code for the userspace copy of
the TCE table and since it is big endian, let's make the copy big endian
too.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 22:53:09 +10:00
Jason Gunthorpe bb94b55af3 vfio: Use get_user_pages_longterm correctly
The patch noted in the fixes below converted get_user_pages_fast() to
get_user_pages_longterm(), however the two calls differ in a few ways.

First _fast() is documented to not require the mmap_sem, while _longterm()
is documented to need it. Hold the mmap sem as required.

Second, _fast accepts an 'int write' while _longterm uses 'unsigned int
gup_flags', so the expression '!!(prot & IOMMU_WRITE)' is only working by
luck as FOLL_WRITE is currently == 0x1. Use the expected FOLL_WRITE
constant instead.

Fixes: 94db151dc8 ("vfio: disable filesystem-dax page pinning")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-30 13:58:09 -06:00
Alex Williamson 08ca1b52f6 vfio/pci: Make IGD support a configurable option
Allow the code which provides extensions to support direct assignment
of Intel IGD (GVT-d) to be compiled out of the kernel if desired.  The
config option for this was previously automatically enabled on X86,
therefore the default remains Y.  This simply provides the option to
disable it even for X86.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-18 16:39:50 -06:00
Linus Torvalds 467590e055 Merge tag 'vfio-v4.18-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:

 - Bind type1 task tracking to group_leader to facilitate vCPU hotplug
   in QEMU (Alex Williamson)

 - Sample mdev display drivers, including region-based host and guest
   Linux drivers and bochs compatible dmabuf device
   (Gerd Hoffmann)

 - Fix vfio-platform reset module leak (Geert Uytterhoeven)

 - vfio-platform error message consistency (Geert Uytterhoeven)

 - Global checking for mdev uuid collisions rather than per parent
   device (Alex Williamson)

 - Use match_string() helper (Yisheng Xie)

 - vfio-platform PM domain fixes (Geert Uytterhoeven)

 - Fix sample mbochs driver build dependency (Arnd Bergmann)

* tag 'vfio-v4.18-rc1' of git://github.com/awilliam/linux-vfio:
  samples: mbochs: add DMA_SHARED_BUFFER dependency
  vfio: platform: Fix using devices in PM Domains
  vfio: use match_string() helper
  vfio/mdev: Re-order sysfs attribute creation
  vfio/mdev: Check globally for duplicate devices
  vfio: platform: Make printed error messages more consistent
  vfio: platform: Fix reset module leak in error path
  sample: vfio bochs vbe display (host device for bochs-drm)
  sample: vfio mdev display - guest driver
  sample: vfio mdev display - host device
  vfio/type1: Fix task tracking for QEMU vCPU hotplug
2018-06-12 13:11:26 -07:00
Geert Uytterhoeven 415eb9fc0e vfio: platform: Fix using devices in PM Domains
If a device is part of a PM Domain (e.g. power and/or clock domain), its
power state is managed using Runtime PM.  Without Runtime PM, the device
may not be powered up or clocked, causing subtle failures, crashes, or
system lock-ups when the device is accessed by the guest.

Fix this by adding Runtime PM support, powering the device when the VFIO
device is opened by the guest.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-08 10:24:37 -06:00
Yisheng Xie e77addf018 vfio: use match_string() helper
match_string() returns the index of an array for a matching string,
which can be used intead of open coded variant.

Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-08 10:24:33 -06:00