Commit Graph

1136953 Commits

Author SHA1 Message Date
Quentin Perret
315775ff7c KVM: arm64: Consolidate stage-2 initialisation into a single function
The initialisation of guest stage-2 page-tables is currently split
across two functions: kvm_init_stage2_mmu() and kvm_arm_setup_stage2().
That is presumably for historical reasons as kvm_arm_setup_stage2()
originates from the (now defunct) KVM port for 32-bit Arm.

Simplify this code path by merging both functions into one, taking care
to map the 'struct kvm' into the hypervisor stage-1 early on in order to
simplify the failure path.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Co-developed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-19-will@kernel.org
2022-11-11 17:16:25 +00:00
Quentin Perret
717a7eebac KVM: arm64: Add generic hyp_memcache helpers
The host at EL1 and the pKVM hypervisor at EL2 will soon need to
exchange memory pages dynamically for creating and destroying VM state.

Indeed, the hypervisor will rely on the host to donate memory pages it
can use to create guest stage-2 page-tables and to store VM and vCPU
metadata. In order to ease this process, introduce a
'struct hyp_memcache' which is essentially a linked list of available
pages, indexed by physical addresses so that it can be passed
meaningfully between the different virtual address spaces configured at
EL1 and EL2.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-18-will@kernel.org
2022-11-11 17:16:25 +00:00
Will Deacon
13e248aab7 KVM: arm64: Provide I-cache invalidation by virtual address at EL2
In preparation for handling cache maintenance of guest pages from within
the pKVM hypervisor at EL2, introduce an EL2 copy of icache_inval_pou()
which will later be plumbed into the stage-2 page-table cache
maintenance callbacks, ensuring that the initial contents of pages
mapped as executable into the guest stage-2 page-table is visible to the
instruction fetcher.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-17-will@kernel.org
2022-11-11 17:16:25 +00:00
Will Deacon
6c165223e9 KVM: arm64: Initialise hypervisor copies of host symbols unconditionally
The nVHE object at EL2 maintains its own copies of some host variables
so that, when pKVM is enabled, the host cannot directly modify the
hypervisor state. When running in normal nVHE mode, however, these
variables are still mirrored at EL2 but are not initialised.

Initialise the hypervisor symbols from the host copies regardless of
pKVM, ensuring that any reference to this data at EL2 with normal nVHE
will return a sensibly initialised value.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-16-will@kernel.org
2022-11-11 17:16:25 +00:00
Quentin Perret
aa6948f82f KVM: arm64: Add per-cpu fixmap infrastructure at EL2
Mapping pages in a guest page-table from within the pKVM hypervisor at
EL2 may require cache maintenance to ensure that the initialised page
contents is visible even to non-cacheable (e.g. MMU-off) accesses from
the guest.

In preparation for performing this maintenance at EL2, introduce a
per-vCPU fixmap which allows the pKVM hypervisor to map guest pages
temporarily into its stage-1 page-table for the purposes of cache
maintenance and, in future, poisoning on the reclaim path. The use of a
fixmap avoids the need for memory allocation or locking on the map()
path.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Co-developed-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-15-will@kernel.org
2022-11-11 17:16:25 +00:00
Fuad Tabba
9d0c063a4d KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from EL1
With the pKVM hypervisor at EL2 now offering hypercalls to the host for
creating and destroying VM and vCPU structures, plumb these in to the
existing arm64 KVM backend to ensure that the hypervisor data structures
are allocated and initialised on first vCPU run for a pKVM guest.

In the host, 'struct kvm_protected_vm' is introduced to hold the handle
of the pKVM VM instance as well as to track references to the memory
donated to the hypervisor so that it can be freed back to the host
allocator following VM teardown. The stage-2 page-table, hypervisor VM
and vCPU structures are allocated separately so as to avoid the need for
a large physically-contiguous allocation in the host at run-time.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-14-will@kernel.org
2022-11-11 17:16:24 +00:00
Fuad Tabba
a1ec5c70d3 KVM: arm64: Add infrastructure to create and track pKVM instances at EL2
Introduce a global table (and lock) to track pKVM instances at EL2, and
provide hypercalls that can be used by the untrusted host to create and
destroy pKVM VMs and their vCPUs. pKVM VM/vCPU state is directly
accessible only by the trusted hypervisor (EL2).

Each pKVM VM is directly associated with an untrusted host KVM instance,
and is referenced by the host using an opaque handle. Future patches
will provide hypercalls to allow the host to initialize/set/get pKVM
VM/vCPU state using the opaque handle.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Co-developed-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
[maz: silence warning on unmap_donated_memory_noclear()]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-13-will@kernel.org
2022-11-11 17:16:05 +00:00
Will Deacon
5304002dc3 KVM: arm64: Rename 'host_kvm' to 'host_mmu'
In preparation for introducing VM and vCPU state at EL2, rename the
existing 'struct host_kvm' and its singleton 'host_kvm' instance to
'host_mmu' so as to avoid confusion between the structure tracking the
host stage-2 MMU state and the host instance of a 'struct kvm' for a
protected guest.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-12-will@kernel.org
2022-11-11 16:40:54 +00:00
Fuad Tabba
1c80002e32 KVM: arm64: Add hyp_spinlock_t static initializer
Introduce a static initializer macro for 'hyp_spinlock_t' so that it is
straightforward to instantiate global locks at EL2. This will be later
utilised for locking the VM table in the hypervisor.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-11-will@kernel.org
2022-11-11 16:40:54 +00:00
Will Deacon
4d968b12e6 KVM: arm64: Include asm/kvm_mmu.h in nvhe/mem_protect.h
nvhe/mem_protect.h refers to __load_stage2() in the definition of
__load_host_stage2() but doesn't include the relevant header.

Include asm/kvm_mmu.h in nvhe/mem_protect.h so that users of the latter
don't have to do this themselves.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-10-will@kernel.org
2022-11-11 16:40:54 +00:00
Quentin Perret
9926cfce8d KVM: arm64: Add helpers to pin memory shared with the hypervisor at EL2
Add helpers allowing the hypervisor to check whether a range of pages
are currently shared by the host, and 'pin' them if so by blocking host
unshare operations until the memory has been unpinned.

This will allow the hypervisor to take references on host-provided
data-structures (e.g. 'struct kvm') with the guarantee that these pages
will remain in a stable state until the hypervisor decides to release
them, for example during guest teardown.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-9-will@kernel.org
2022-11-11 16:40:54 +00:00
Quentin Perret
43c1ff8b75 KVM: arm64: Prevent the donation of no-map pages
Memory regions marked as "no-map" in the host device-tree routinely
include TrustZone carev-outs and DMA pools. Although donating such pages
to the hypervisor may not breach confidentiality, it could be used to
corrupt its state in uncontrollable ways. To prevent this, let's block
host-initiated memory transitions targeting "no-map" pages altogether in
nVHE protected mode as there should be no valid reason to do this in
current operation.

Thankfully, the pKVM EL2 hypervisor has a full copy of the host's list
of memblock regions, so we can easily check for the presence of the
MEMBLOCK_NOMAP flag on a region containing pages being donated from the
host.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-8-will@kernel.org
2022-11-11 16:40:54 +00:00
Will Deacon
1ed5c24c26 KVM: arm64: Implement do_donate() helper for donating memory
Transferring ownership information of a memory region from one component
to another can be achieved using a "donate" operation, which results
in the previous owner losing access to the underlying pages entirely
and the new owner having exclusive access to the page.

Implement a do_donate() helper, along the same lines as do_{un,}share,
and provide this functionality for the host-{to,from}-hyp cases as this
will later be used to donate/reclaim memory pages to store VM metadata
at EL2.

In a similar manner to the sharing transitions, permission checks are
performed by the hypervisor to ensure that the component initiating the
transition really is the owner of the page and also that the completer
does not currently have a page mapped at the target address.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Co-developed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-7-will@kernel.org
2022-11-11 16:40:54 +00:00
Will Deacon
33bc332d40 KVM: arm64: Unify identifiers used to distinguish host and hypervisor
The 'pkvm_component_id' enum type provides constants to refer to the
host and the hypervisor, yet this information is duplicated by the
'pkvm_hyp_id' constant.

Remove the definition of 'pkvm_hyp_id' and move the 'pkvm_component_id'
type definition to 'mem_protect.h' so that it can be used outside of
the memory protection code, for example when initialising the owner for
hypervisor-owned pages.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-6-will@kernel.org
2022-11-11 16:40:54 +00:00
Quentin Perret
0d16d12eb2 KVM: arm64: Fix-up hyp stage-1 refcounts for all pages mapped at EL2
In order to allow unmapping arbitrary memory pages from the hypervisor
stage-1 page-table, fix-up the initial refcount for pages that have been
mapped before the 'vmemmap' array was up and running so that it
accurately accounts for all existing hypervisor mappings.

This is achieved by traversing the entire hypervisor stage-1 page-table
during initialisation of EL2 and updating the corresponding
'struct hyp_page' for each valid mapping.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-5-will@kernel.org
2022-11-11 16:40:54 +00:00
Quentin Perret
8e6bcc3a45 KVM: arm64: Back the hypervisor 'struct hyp_page' array for all memory
The EL2 'vmemmap' array in nVHE Protected mode is currently very sparse:
only memory pages owned by the hypervisor itself have a matching 'struct
hyp_page'. However, as the size of this struct has been reduced
significantly since its introduction, it appears that we can now afford
to back the vmemmap for all of memory.

Having an easily accessible 'struct hyp_page' for every physical page in
memory provides the hypervisor with a simple mechanism to store metadata
(e.g. a refcount) that wouldn't otherwise fit in the very limited number
of software bits available in the host stage-2 page-table entries. This
will be used in subsequent patches when pinning host memory pages for
use by the hypervisor at EL2.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-4-will@kernel.org
2022-11-11 16:40:54 +00:00
Quentin Perret
72a5bc0f15 KVM: arm64: Allow attaching of non-coalescable pages to a hyp pool
All the contiguous pages used to initialize a 'struct hyp_pool' are
considered coalescable, which means that the hyp page allocator will
actively try to merge them with their buddies on the hyp_put_page() path.
However, using hyp_put_page() on a page that is not part of the inital
memory range given to a hyp_pool() is currently unsupported.

In order to allow dynamically extending hyp pools at run-time, add a
check to __hyp_attach_page() to allow inserting 'external' pages into
the free-list of order 0. This will be necessary to allow lazy donation
of pages from the host to the hypervisor when allocating guest stage-2
page-table pages at EL2.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-3-will@kernel.org
2022-11-11 16:40:54 +00:00
Quentin Perret
0f4f7ae10e KVM: arm64: Move hyp refcount manipulation helpers to common header file
We will soon need to manipulate 'struct hyp_page' refcounts from outside
page_alloc.c, so move the helpers to a common header file to allow them
to be reused easily.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-2-will@kernel.org
2022-11-11 16:40:54 +00:00
Linus Torvalds
30a0b95b13 Linux 6.1-rc3 v6.1-rc3 2022-10-30 15:19:28 -07:00
Linus Torvalds
b72018ab82 Merge tag 'fbdev-for-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev
Pull fbdev fixes from Helge Deller:
 "A use-after-free bugfix in the smscufx driver and various minor error
  path fixes, smaller build fixes, sysfs fixes and typos in comments in
  the stifb, sisfb, da8xxfb, xilinxfb, sm501fb, gbefb and cyber2000fb
  drivers"

* tag 'fbdev-for-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
  fbdev: cyber2000fb: fix missing pci_disable_device()
  fbdev: sisfb: use explicitly signed char
  fbdev: smscufx: Fix several use-after-free bugs
  fbdev: xilinxfb: Make xilinxfb_release() return void
  fbdev: sisfb: fix repeated word in comment
  fbdev: gbefb: Convert sysfs snprintf to sysfs_emit
  fbdev: sm501fb: Convert sysfs snprintf to sysfs_emit
  fbdev: stifb: Fall back to cfb_fillrect() on 32-bit HCRX cards
  fbdev: da8xx-fb: Fix error handling in .remove()
  fbdev: MIPS supports iomem addresses
2022-10-30 11:31:14 -07:00
Linus Torvalds
9f127546bb Merge tag 'char-misc-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc fixes from Greg KH:
 "Some small driver fixes for 6.1-rc3.  They include:

   - iio driver bugfixes

   - counter driver bugfixes

   - coresight bugfixes, including a revert and then a second fix to get
     it right.

  All of these have been in linux-next with no reported problems"

* tag 'char-misc-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (21 commits)
  misc: sgi-gru: use explicitly signed char
  coresight: cti: Fix hang in cti_disable_hw()
  Revert "coresight: cti: Fix hang in cti_disable_hw()"
  counter: 104-quad-8: Fix race getting function mode and direction
  counter: microchip-tcb-capture: Handle Signal1 read and Synapse
  coresight: cti: Fix hang in cti_disable_hw()
  coresight: Fix possible deadlock with lock dependency
  counter: ti-ecap-capture: fix IS_ERR() vs NULL check
  counter: Reduce DEFINE_COUNTER_ARRAY_POLARITY() to defining counter_array
  iio: bmc150-accel-core: Fix unsafe buffer attributes
  iio: adxl367: Fix unsafe buffer attributes
  iio: adxl372: Fix unsafe buffer attributes
  iio: at91-sama5d2_adc: Fix unsafe buffer attributes
  iio: temperature: ltc2983: allocate iio channels once
  tools: iio: iio_utils: fix digit calculation
  iio: adc: stm32-adc: fix channel sampling time init
  iio: adc: mcp3911: mask out device ID in debug prints
  iio: adc: mcp3911: use correct id bits
  iio: adc: mcp3911: return proper error code on failure to allocate trigger
  iio: adc: mcp3911: fix sizeof() vs ARRAY_SIZE() bug
  ...
2022-10-30 11:22:33 -07:00
Linus Torvalds
c4d25ce6e9 Merge tag 'usb-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
 "A few small USB fixes for 6.1-rc3. Include in here are:

   - MAINTAINERS update, including a big one for the USB gadget
     subsystem. Many thanks to Felipe for all of the years of hard work
     he has done on this codebase, it was greatly appreciated.

   - dwc3 driver fixes for reported problems.

   - xhci driver fixes for reported problems.

   - typec driver fixes for minor issues

   - uvc gadget driver change, and then revert as it wasn't relevant for
     6.1-final, as it is a new feature and people are still reviewing
     and modifying it.

  All of these have been in the linux-next tree with no reported issues"

* tag 'usb-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: dwc3: gadget: Don't set IMI for no_interrupt
  usb: dwc3: gadget: Stop processing more requests on IMI
  Revert "usb: gadget: uvc: limit isoc_sg to super speed gadgets"
  xhci: Remove device endpoints from bandwidth list when freeing the device
  xhci-pci: Set runtime PM as default policy on all xHC 1.2 or later devices
  xhci: Add quirk to reset host back to default state at shutdown
  usb: xhci: add XHCI_SPURIOUS_SUCCESS to ASM1042 despite being a V0.96 controller
  usb: dwc3: st: Rely on child's compatible instead of name
  usb: gadget: uvc: limit isoc_sg to super speed gadgets
  usb: bdc: change state when port disconnected
  usb: typec: ucsi: acpi: Implement resume callback
  usb: typec: ucsi: Check the connection on resume
  usb: gadget: aspeed: Fix probe regression
  usb: gadget: uvc: fix sg handling during video encode
  usb: gadget: uvc: fix sg handling in error case
  usb: gadget: uvc: fix dropped frame after missed isoc
  usb: dwc3: gadget: Don't delay End Transfer on delayed_status
  usb: dwc3: Don't switch OTG -> peripheral if extcon is present
  MAINTAINERS: Update maintainers for broadcom USB
  MAINTAINERS: move USB gadget and phy entries under the main USB entry
2022-10-30 10:35:07 -07:00
Linus Torvalds
ef3c0949b9 Merge tag 'gpio-fixes-for-v6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fixes from Bartosz Golaszewski:

 - convert gpio-tegra to using an immutable irqchip

 - MAINTAINERS update

* tag 'gpio-fixes-for-v6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  MAINTAINERS: Change myself to a maintainer
  gpio: tegra: Convert to immutable irq chip
2022-10-30 10:21:42 -07:00
Linus Torvalds
434766058e Merge tag 'perf_urgent_for_v6.1_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:

 - Rename a perf memory level event define to denote it is of CXL type

 - Add Alder and Raptor Lakes support to RAPL

 - Make sure raw sample data is output with tracepoints

* tag 'perf_urgent_for_v6.1_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/mem: Rename PERF_MEM_LVLNUM_EXTN_MEM to PERF_MEM_LVLNUM_CXL
  perf/x86/rapl: Add support for Intel Raptor Lake
  perf/x86/rapl: Add support for Intel AlderLake-N
  perf: Fix missing raw data on tracepoint events
2022-10-30 09:49:18 -07:00
Linus Torvalds
c96bb958fb Merge tag 'loongarch-fixes-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch fixes from Huacai Chen:
 "Remove unused kernel stack padding, fix some build errors/warnings and
  two bugs in laptop platform driver"

* tag 'loongarch-fixes-6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  platform/loongarch: laptop: Fix possible UAF and simplify generic_acpi_laptop_init()
  platform/loongarch: laptop: Adjust resume order for loongson_hotkey_resume()
  LoongArch: BPF: Avoid declare variables in switch-case
  LoongArch: Use flexible-array member instead of zero-length array
  LoongArch: Remove unused kernel stack padding
2022-10-30 09:44:06 -07:00
Linus Torvalds
28b7bd4ad2 Merge tag '6.1-rc2-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:

 - use after free fix for reconnect race

 - two memory leak fixes

* tag '6.1-rc2-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix use-after-free caused by invalid pointer `hostname`
  cifs: Fix pages leak when writedata alloc failed in cifs_write_from_iter()
  cifs: Fix pages array leak when writedata alloc failed in cifs_writedata_alloc()
2022-10-30 09:40:04 -07:00
Linus Torvalds
882ad2a2a8 Merge tag 'random-6.1-rc3-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random
Pull random number generator fix from Jason Donenfeld:
 "One fix from Jean-Philippe Brucker, addressing a regression in which
  early boot code on ARM64 would use the non-_early variant of the
  arch_get_random family of functions, resulting in the architectural
  random number generator appearing unavailable during that early phase
  of boot.

  The fix simply changes arch_get_random*() to arch_get_random*_early().

  This distinction between these two functions is a bit of an old wart
  I'm not a fan of, and for 6.2 I'll see if I can make obsolete the
  _early variant, so that one function does the right thing in all
  contexts without overhead"

* tag 'random-6.1-rc3-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  random: use arch_get_random*_early() in random_init()
2022-10-29 18:33:03 -07:00
Linus Torvalds
83633ed70c Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
 "Varions small  fixes, all  in drivers.

  Some of these arrived during the merge window and got held over to
  make sure of testing on the -rc tree.

  The biggest change is for standards conformance in the target driver,
  closely followed by a set of bug fixes in megaraid_sas"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
  scsi: ufs: core: Fix typo in comment
  scsi: mpi3mr: Select CONFIG_SCSI_SAS_ATTRS
  scsi: ufs: core: Fix typo for register name in comments
  scsi: pm80xx: Display proc_name in sysfs
  scsi: ufs: core: Fix the error log in ufshcd_query_flag_retry()
  scsi: ufs: core: Remove unneeded casts from void *
  scsi: lpfc: Fix spelling mistake "unsolicted" -> "unsolicited"
  scsi: qla2xxx: Use transport-defined speed mask for supported_speeds
  scsi: target: iblock: Fold iblock_emulate_read_cap_with_block_size() into iblock_get_blocks()
  scsi: qla2xxx: Fix serialization of DCBX TLV data request
  scsi: ufs: qcom: Remove redundant dev_err() call
  scsi: megaraid_sas: Move megasas_dbg_lvl init to megasas_init()
  scsi: megaraid_sas: Remove unnecessary memset()
  scsi: megaraid_sas: Simplify megasas_update_device_list
  scsi: megaraid_sas: Correct an error message
  scsi: megaraid_sas: Correct value passed to scsi_device_lookup()
  scsi: target: core: UA on all LUNs after reset
  scsi: target: core: New key must be used for moved PR
  scsi: target: core: Abort all preempted regs if requested
  scsi: target: core: Fix memory leak in preempt_and_abort
  ...
2022-10-29 18:12:45 -07:00
Linus Torvalds
c6e0e874a8 Merge tag 'block-6.1-2022-10-28' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:

 - NVMe pull request via Christoph:
      - make the multipath dma alignment match the non-multipath one
        (Keith Busch)
      - fix a bogus use of sg_init_marker() (Nam Cao)
      - fix circulr locking in nvme-tcp (Sagi Grimberg)

 - Initialization fix for requests allocated via the special hw queue
   allocator (John)

 - Fix for a regression added in this release with the batched
   completions of end_io backed requests (Ming)

 - Error handling leak fix for rbd (Yang)

 - Error handling leak fix for add_disk() failure (Yu)

* tag 'block-6.1-2022-10-28' of git://git.kernel.dk/linux:
  blk-mq: Properly init requests from blk_mq_alloc_request_hctx()
  blk-mq: don't add non-pt request with ->end_io to batch
  rbd: fix possible memory leak in rbd_sysfs_init()
  nvme-multipath: set queue dma alignment to 3
  nvme-tcp: fix possible circular locking when deleting a controller under memory pressure
  nvme-tcp: replace sg_init_marker() with sg_init_table()
  block: fix memory leak for elevator on add_disk failure
2022-10-29 18:06:52 -07:00
Linus Torvalds
4d244327dd Merge tag 'io_uring-6.1-2022-10-28' of git://git.kernel.dk/linux
Pull io_uring fix from Jens Axboe:
 "Just a fix for a locking regression introduced with the deferred
  task_work running from this merge window"

* tag 'io_uring-6.1-2022-10-28' of git://git.kernel.dk/linux:
  io_uring: unlock if __io_run_local_work locked inside
  io_uring: use io_run_local_work_locked helper
2022-10-29 18:01:16 -07:00
Linus Torvalds
3c339dbd13 Merge tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc hotfixes from Andrew Morton:
 "Eight fix pre-6.0 bugs and the remainder address issues which were
  introduced in the 6.1-rc merge cycle, or address issues which aren't
  considered sufficiently serious to warrant a -stable backport"

* tag 'mm-hotfixes-stable-2022-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits)
  mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region
  lib: maple_tree: remove unneeded initialization in mtree_range_walk()
  mmap: fix remap_file_pages() regression
  mm/shmem: ensure proper fallback if page faults
  mm/userfaultfd: replace kmap/kmap_atomic() with kmap_local_page()
  x86: fortify: kmsan: fix KMSAN fortify builds
  x86: asm: make sure __put_user_size() evaluates pointer once
  Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default
  x86/purgatory: disable KMSAN instrumentation
  mm: kmsan: export kmsan_copy_page_meta()
  mm: migrate: fix return value if all subpages of THPs are migrated successfully
  mm/uffd: fix vma check on userfault for wp
  mm: prep_compound_tail() clear page->private
  mm,madvise,hugetlb: fix unexpected data loss with MADV_DONTNEED on hugetlbfs
  mm/page_isolation: fix clang deadcode warning
  fs/ext4/super.c: remove unused `deprecated_msg'
  ipc/msg.c: fix percpu_counter use after free
  memory tier, sysfs: rename attribute "nodes" to "nodelist"
  MAINTAINERS: git://github.com -> https://github.com for nilfs2
  mm/kmemleak: prevent soft lockup in kmemleak_scan()'s object iteration loops
  ...
2022-10-29 17:49:33 -07:00
Linus Torvalds
91562cf993 Merge tag 'powerpc-6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:

 - Fix a case of rescheduling with user access unlocked, when preempt is
   enabled.

 - A follow-up fix for a recent fix, which could lead to IRQ state
   assertions firing incorrectly.

 - Two fixes for lockdep warnings seen when using kfence with the Hash
   MMU.

 - Two fixes for preempt warnings seen when using the Hash MMU.

 - Two fixes for the VAS coprocessor mechanism used on pseries.

 - Prevent building some of our older KVM backends when
   CONTEXT_TRACKING_USER is enabled, as it's known to cause crashes.

 - A couple of fixes for issues seen with PMU NMIs.

Thanks to Nicholas Piggin, Guenter Roeck, Frederic Barrat Haren Myneni,
Sachin Sant, and Samuel Holland.

* tag 'powerpc-6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s/interrupt: Fix clear of PACA_IRQS_HARD_DIS when returning to soft-masked context
  powerpc/64s/interrupt: Perf NMI should not take normal exit path
  powerpc/64/interrupt: Prevent NMI PMI causing a dangerous warning
  KVM: PPC: BookS PR-KVM and BookE do not support context tracking
  powerpc: Fix reschedule bug in KUAP-unlocked user copy
  powerpc/64s: Fix hash__change_memory_range preemption warning
  powerpc/64s: Disable preemption in hash lazy mmu mode
  powerpc/64s: make linear_map_hash_lock a raw spinlock
  powerpc/64s: make HPTE lock and native_tlbie_lock irq-safe
  powerpc/64s: Add lockdep for HPTE lock
  powerpc/pseries: Use lparcfg to reconfig VAS windows for DLPAR CPU
  powerpc/pseries/vas: Add VAS IRQ primary handler
2022-10-29 10:35:17 -07:00
Yang Yingliang
d81916910f platform/loongarch: laptop: Fix possible UAF and simplify generic_acpi_laptop_init()
Currently the return value of 'sub_driver->init' is not checked. If
sparse_keymap_setup() called in the init function fails, 'generic_
inputdev' is freed, then it will lead a UAF when using it in generic_
acpi_laptop_init(). Fix it by checking the return value and setting
generic_inputdev to NULL after free, so as to avoid double free it.

The error code in generic_subdriver_init() is always negative, so the
return of generic_subdriver_init() can be simplified.

Fixes: 6246ed0911 ("LoongArch: Add ACPI-based generic laptop driver")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29 16:29:31 +08:00
Huacai Chen
fbe605ab15 platform/loongarch: laptop: Adjust resume order for loongson_hotkey_resume()
Some laptops don't support SW_LID, but still have backlight control,
move backlight resuming before SW_LID event handling so as to avoid
backlight mistake due to early return.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29 16:29:31 +08:00
Huacai Chen
bbfddb904d LoongArch: BPF: Avoid declare variables in switch-case
Not all compilers support declare variables in switch-case, so move
declarations to the beginning of a function. Otherwise we may get such
build errors:

arch/loongarch/net/bpf_jit.c: In function ‘emit_atomic’:
arch/loongarch/net/bpf_jit.c:362:3: error: a label can only be part of a statement and a declaration is not a statement
   u8 r0 = regmap[BPF_REG_0];
   ^~
arch/loongarch/net/bpf_jit.c: In function ‘build_insn’:
arch/loongarch/net/bpf_jit.c:727:3: error: a label can only be part of a statement and a declaration is not a statement
   u8 t7 = -1;
   ^~
arch/loongarch/net/bpf_jit.c:778:3: error: a label can only be part of a statement and a declaration is not a statement
   int ret;
   ^~~
arch/loongarch/net/bpf_jit.c:779:3: error: expected expression before ‘u64’
   u64 func_addr;
   ^~~
arch/loongarch/net/bpf_jit.c:780:3: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
   bool func_addr_fixed;
   ^~~~
arch/loongarch/net/bpf_jit.c:784:11: error: ‘func_addr’ undeclared (first use in this function); did you mean ‘in_addr’?
          &func_addr, &func_addr_fixed);
           ^~~~~~~~~
           in_addr
arch/loongarch/net/bpf_jit.c:784:11: note: each undeclared identifier is reported only once for each function it appears in
arch/loongarch/net/bpf_jit.c:814:3: error: a label can only be part of a statement and a declaration is not a statement
   u64 imm64 = (u64)(insn + 1)->imm << 32 | (u32)insn->imm;
   ^~~

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29 16:29:31 +08:00
Yushan Zhou
4805a13d54 LoongArch: Use flexible-array member instead of zero-length array
Eliminate the following coccicheck warning:
./arch/loongarch/include/asm/ptrace.h:32:15-21: WARNING use flexible-array member instead

Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Yushan Zhou <katrinzhou@tencent.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29 16:29:31 +08:00
Jinyang He
b40fa75e15 LoongArch: Remove unused kernel stack padding
The current LoongArch kernel stack is padded as if obeying the MIPS o32
calling convention (32 bytes), signifying the port's MIPS lineage but no
longer making sense. Remove the padding for clarity.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29 16:29:31 +08:00
Linus Torvalds
576e61cea1 Merge tag 's390-6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Vasily Gorbik:

 - Remove outdated linux390 link from MAINTAINERS

 - Add few missing EX_TABLE entries to inline assemblies

 - Fix raw data collection for pai_ext PMU

 - Add kernel image secure boot trailer for future firmware versions

 - Fix out-of-bounds access on cio_ignore free

 - Fix memory allocation of mdev_types array in vfio-ap

* tag 's390-6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/vfio-ap: Fix memory allocation for mdev_types array
  s390/cio: fix out-of-bounds access on cio_ignore free
  s390/pai: fix raw data collection for PMU pai_ext
  s390/boot: add secure boot trailer
  s390/pci: add missing EX_TABLE entries to __pcistg_mio_inuser()/__pcilg_mio_inuser()
  s390/futex: add missing EX_TABLE entry to __futex_atomic_op()
  s390/uaccess: add missing EX_TABLE entries to __clear_user()
  MAINTAINERS: remove outdated linux390 link
2022-10-28 17:11:26 -07:00
Linus Torvalds
283f13d43b Merge tag 'riscv-for-linus-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:

 - A fix for a build warning in the jump_label code

 - One of the git://github -> https://github cleanups, for the SiFive
   drivers

 - A fix for the kasan initialization code, this still likely warrants
   some cleanups but that's a bigger problem and at least this fixes the
   crashes in the short term

 - A pair of fixes for extension support detection on mixed LLVM/GNU
   toolchains

 - A fix for a runtime warning in the /proc/cpuinfo code

* tag 'riscv-for-linus-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  RISC-V: Fix /proc/cpuinfo cpumask warning
  riscv: fix detection of toolchain Zihintpause support
  riscv: fix detection of toolchain Zicbom support
  riscv: mm: add missing memcpy in kasan_init
  MAINTAINERS: git://github.com -> https://github.com for sifive
  riscv: jump_label: mark arguments as const to satisfy asm constraints
2022-10-28 17:03:00 -07:00
Linus Torvalds
13f05fb219 Merge tag 'acpi-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and device properties fixes from Rafael Wysocki:
 "These fix device properties documentation and the ACPI PCC code, add a
  new IRQ override quirk for resource handling and add one more item to
  the list of device IDs to be ignored when returned by _DEP.

  Specifics:

   - Fix the documentation of the *_match_string() family of functions
     to properly cover the return value (Andy Shevchenko)

   - Fix a possible integer overflow during multiplication in the ACPI
     PCC code (Manank Patel)

   - Make the ACPI device resources code skip IRQ override on Asus
     Vivobook S5602ZA (Tamim Khan)

   - Add LATT2021 to the list of device IDs that are ignored when
     returned by _DEP, because there are no drivers for them in the
     kernel and no plans to add such drivers (Hans de Goede)"

* tag 'acpi-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: scan: Add LATT2021 to acpi_ignore_dep_ids[]
  ACPI: resource: Skip IRQ override on Asus Vivobook S5602ZA
  ACPI: PCC: Fix unintentional integer overflow
  device property: Fix documentation for *_match_string() APIs
2022-10-28 16:48:29 -07:00
Linus Torvalds
6b872a5ece Merge tag 'pm-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
 "These make the intel_pstate driver work as expected on all hybrid
  platforms to date (regardless of possible platform firmware issues),
  fix hybrid sleep on systems using suspend-to-idle by default, make the
  generic power domains code handle disabled idle states properly and
  update pm-graph.

  Specifics:

   - Make intel_pstate use what is known about the hardware instead of
     relying on information from the platform firmware (ACPI CPPC in
     particular) to establish the relationship between the HWP CPU
     performance levels and frequencies on all hybrid platforms
     available to date (Rafael Wysocki)

   - Allow hybrid sleep to use suspend-to-idle as a system suspend
     method if it is the current suspend method of choice (Mario
     Limonciello)

   - Fix handling of unavailable/disabled idle states in the generic
     power domains code (Sudeep Holla)

   - Update the pm-graph suite of utilities to version 5.10 which is
     fixes-mostly and does not add any new features (Todd Brandt)"

* tag 'pm-6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: domains: Fix handling of unavailable/disabled idle states
  pm-graph v5.10
  cpufreq: intel_pstate: hybrid: Use known scaling factor for P-cores
  cpufreq: intel_pstate: Read all MSRs on the target CPU
  PM: hibernate: Allow hybrid sleep to work with s2idle
2022-10-28 16:44:12 -07:00
Jean-Philippe Brucker
f5e4ec155d random: use arch_get_random*_early() in random_init()
While reworking the archrandom handling, commit d349ab99ee ("random:
handle archrandom with multiple longs") switched to the non-early
archrandom helpers in random_init(), which broke initialization of the
entropy pool from the arm64 random generator.

Indeed at that point the arm64 CPU features, which verify that all CPUs
have compatible capabilities, are not finalized so arch_get_random_seed_longs()
is unsuccessful. Instead random_init() should use the _early functions,
which check only the boot CPU on arm64. On other architectures the
_early functions directly call the normal ones.

Fixes: d349ab99ee ("random: handle archrandom with multiple longs")
Cc: stable@vger.kernel.org
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-29 00:24:03 +02:00
Sebastian Andrzej Siewior
dda1c41a07 mm: multi-gen LRU: move lru_gen_add_mm() out of IRQ-off region
lru_gen_add_mm() has been added within an IRQ-off region in the commit
mentioned below.  The other invocations of lru_gen_add_mm() are not within
an IRQ-off region.

The invocation within IRQ-off region is problematic on PREEMPT_RT because
the function is using a spin_lock_t which must not be used within
IRQ-disabled regions.

The other invocations of lru_gen_add_mm() occur while
task_struct::alloc_lock is acquired.  Move lru_gen_add_mm() after
interrupts are enabled and before task_unlock().

Link: https://lkml.kernel.org/r/20221026134830.711887-1-bigeasy@linutronix.de
Fixes: bd74fdaea1 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Yu Zhao <yuzhao@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Lukas Bulwahn
1b9c918318 lib: maple_tree: remove unneeded initialization in mtree_range_walk()
Before the do-while loop in mtree_range_walk(), the variables next, min,
max need to be initialized.  The variables last, prev_min and prev_max are
set within the loop body before they are eventually used after exiting the
loop body.

As it is a do-while loop, the loop body is executed at least once, so the
variables last, prev_min and prev_max do not need to be initialized before
the loop body.

Remove unneeded initialization of last and prev_min.

The needless initialization was reported by clang-analyzer as Dead Stores.

As the compiler already identifies these assignments as unneeded, it
optimizes the assignments away.  Hence:

No functional change. No change in object code.

Link: https://lkml.kernel.org/r/20221026120029.12555-2-lukas.bulwahn@gmail.com
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Liam Howlett
1db43d3f37 mmap: fix remap_file_pages() regression
When using the VMA iterator, the final execution will set the variable
'next' to NULL which causes the function to fail out.  Restore the break
in the loop to exit the VMA iterator early without clearing NULL fixes the
issue.

Link: https://lore.kernel.org/lkml/29344.1666681759@jrobl/
Link: https://lkml.kernel.org/r/20221025161222.2634030-1-Liam.Howlett@oracle.com
Fixes: 763ecb0350 (mm: remove the vma linked list)
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: "J. R. Okajima" <hooanon05g@gmail.com>
Tested-by: "J. R. Okajima" <hooanon05g@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Ira Weiny
5dc21f0c0b mm/shmem: ensure proper fallback if page faults
The kernel test robot flagged a recursive lock as a result of a conversion
from kmap_atomic() to kmap_local_folio()[Link]

The cause was due to the code depending on the kmap_atomic() side effect
of disabling page faults.  In that case the code expects the fault to fail
and take the fallback case.

git archaeology implied that the recursion may not be an actual bug.[1]
However, depending on the implementation of the mmap_lock and the
condition of the call there may still be a deadlock.[2] So this is not
purely a lockdep issue.  Considering a single threaded call stack there
are 3 options.

	1) Different mm's are in play (no issue)
	2) Readlock implementation is recursive and same mm is in play
	   (no issue)
	3) Readlock implementation is _not_ recursive (issue)

The mmap_lock is recursive so with a single thread there is no issue.

However, Matthew pointed out a deadlock scenario when you consider
additional process' and threads thusly.

"The readlock implementation is only recursive if nobody else has taken a
write lock.  If you have a multithreaded process, one of the other threads
can call mmap() and that will prevent recursion (due to fairness).  Even
if it's a different process that you're trying to acquire the mmap read
lock on, you can still get into a deadly embrace.  eg:

process A thread 1 takes read lock on own mmap_lock
process A thread 2 calls mmap, blocks taking write lock
process B thread 1 takes page fault, read lock on own mmap lock
process B thread 2 calls mmap, blocks taking write lock
process A thread 1 blocks taking read lock on process B
process B thread 1 blocks taking read lock on process A

Now all four threads are blocked waiting for each other."

Regardless using pagefault_disable() ensures that no matter what locking
implementation is used a deadlock will not occur.  Add an explicit
pagefault_disable() and a big comment to explain this for future souls
looking at this code.

[1] https://lore.kernel.org/all/Y1MymJ%2FINb45AdaY@iweiny-desk3/
[2] https://lore.kernel.org/lkml/Y1bXBtGTCym77%2FoD@casper.infradead.org/

Link: https://lkml.kernel.org/r/20221025220108.2366043-1-ira.weiny@intel.com
Link: https://lore.kernel.org/r/202210211215.9dc6efb5-yujie.liu@intel.com
Fixes: 7a7256d5f5 ("shmem: convert shmem_mfill_atomic_pte() to use a folio")
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: kernel test robot <yujie.liu@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Ira Weiny
5521de7ddd mm/userfaultfd: replace kmap/kmap_atomic() with kmap_local_page()
kmap() and kmap_atomic() are being deprecated in favor of
kmap_local_page() which is appropriate for any thread local context.[1]

A recent locking bug report with userfaultfd showed that the conversion of
the kmap_atomic()'s in those code flows requires care with regard to the
prevention of deadlock.[2]

git archaeology implied that the recursion may not be an actual bug.[3]
However, depending on the implementation of the mmap_lock and the
condition of the call there may still be a deadlock.[4] So this is not
purely a lockdep issue.  Considering a single threaded call stack there
are 3 options.

	1) Different mm's are in play (no issue)
	2) Readlock implementation is recursive and same mm is in play
	   (no issue)
	3) Readlock implementation is _not_ recursive (issue)

The mmap_lock is recursive so with a single thread there is no issue.

However, Matthew pointed out a deadlock scenario when you consider
additional process' and threads thusly.

"The readlock implementation is only recursive if nobody else has taken a
write lock.  If you have a multithreaded process, one of the other threads
can call mmap() and that will prevent recursion (due to fairness).  Even
if it's a different process that you're trying to acquire the mmap read
lock on, you can still get into a deadly embrace.  eg:

process A thread 1 takes read lock on own mmap_lock
process A thread 2 calls mmap, blocks taking write lock
process B thread 1 takes page fault, read lock on own mmap lock
process B thread 2 calls mmap, blocks taking write lock
process A thread 1 blocks taking read lock on process B
process B thread 1 blocks taking read lock on process A

Now all four threads are blocked waiting for each other."

Regardless using pagefault_disable() ensures that no matter what locking
implementation is used a deadlock will not occur.

Complete kmap conversion in userfaultfd by replacing the kmap() and
kmap_atomic() calls with kmap_local_page().  When replacing the
kmap_atomic() call ensure page faults continue to be disabled to support
the correct fall back behavior and add a comment to inform future souls of
the requirement.

[1] https://lore.kernel.org/all/20220813220034.806698-1-ira.weiny@intel.com/
[2] https://lore.kernel.org/all/Y1Mh2S7fUGQ%2FiKFR@iweiny-desk3/
[3] https://lore.kernel.org/all/Y1MymJ%2FINb45AdaY@iweiny-desk3/
[4] https://lore.kernel.org/lkml/Y1bXBtGTCym77%2FoD@casper.infradead.org/

[ira.weiny@intel.com: v2]
  Link: https://lkml.kernel.org/r/20221025220136.2366143-1-ira.weiny@intel.com
Link: https://lkml.kernel.org/r/20221024043452.1491677-1-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Alexander Potapenko
78a498c3a2 x86: fortify: kmsan: fix KMSAN fortify builds
Ensure that KMSAN builds replace memset/memcpy/memmove calls with the
respective __msan_XXX functions, and that none of the macros are redefined
twice.  This should allow building kernel with both CONFIG_KMSAN and
CONFIG_FORTIFY_SOURCE.

Link: https://lkml.kernel.org/r/20221024212144.2852069-5-glider@google.com
Link: https://github.com/google/kmsan/issues/89
Signed-off-by: Alexander Potapenko <glider@google.com>
Reported-by: Tamas K Lengyel <tamas.lengyel@zentific.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Alexander Potapenko
59c8a02e24 x86: asm: make sure __put_user_size() evaluates pointer once
User access macros must ensure their arguments are evaluated only once if
they are used more than once in the macro body.  Adding
instrument_put_user() to __put_user_size() resulted in double evaluation
of the `ptr` argument, which led to correctness issues when performing
e.g.  unsafe_put_user(..., p++, ...).

To fix those issues, evaluate the `ptr` argument of __put_user_size() at
the beginning of the macro.

Link: https://lkml.kernel.org/r/20221024212144.2852069-4-glider@google.com
Fixes: 888f84a6da ("x86: asm: instrument usercopy in get_user() and put_user()")
Signed-off-by: Alexander Potapenko <glider@google.com>
Reported-by: youling257 <youling257@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00
Alexander Potapenko
921757bc9b Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default
KMSAN adds a lot of instrumentation to the code, which results in
increased stack usage (up to 2048 bytes and more in some cases).  It's
hard to predict how big the stack frames can be, so we disable the
warnings for KMSAN instead.

Link: https://lkml.kernel.org/r/20221024212144.2852069-3-glider@google.com
Link: https://github.com/google/kmsan/issues/89
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-28 13:37:23 -07:00