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The WAN port of the 370-RD has a Marvell PHY, with one LED on
the front panel.y List this LED in the device tree.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Add Switch LED for each port for MikroTik RB3011UiAS-RM.
MikroTik RB3011UiAS-RM is a 10 port device with 2 qca8337 switch chips
connected.
It was discovered that in the hardware design all 3 Switch LED trace of
the related port is connected to the same LED. This was discovered by
setting to 'always on' the related led in the switch regs and noticing
that all 3 LED for the specific port (for example for port 1) cause the
connected LED for port 1 to turn on. As an extra test we tried enabling
2 different LED for the port resulting in the LED turned off only if
every led in the reg was off.
Aside from this funny and strange hardware implementation, the device
itself have one green LED for each port, resulting in 10 green LED one
for each of the 10 supported port.
Cc: Jonathan McDowell <noodles@earth.li>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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IPQ8064 MikroTik RB3011UiAS-RM DT have currently unevaluted properties
in the 2 switch nodes. The bindings #address-cells and #size-cells are
redundant and cause warning for 'Unevaluated properties are not
allowed'.
Drop these bindings to mute these warning as they should not be there
from the start.
Cc: Jonathan McDowell <noodles@earth.li>
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Reviewed-by: Jonathan McDowell <noodles@earth.li>
Tested-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Conflicts:
tools/testing/selftests/net/config
62199e3f1658 ("selftests: net: Add VXLAN MDB test")
3a0385be133e ("selftests: add the missing CONFIG_IP_SCTP in net config")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, and bluetooth.
Not all that quiet given spring celebrations, but "current" fixes are
thinning out, which is encouraging. One outstanding regression in the
mlx5 driver when using old FW, not blocking but we're pushing for a
fix.
Current release - new code bugs:
- eth: enetc: workaround for unresponsive pMAC after receiving
express traffic
Previous releases - regressions:
- rtnetlink: restore RTM_NEW/DELLINK notification behavior, keep the
pid/seq fields 0 for backward compatibility
Previous releases - always broken:
- sctp: fix a potential overflow in sctp_ifwdtsn_skip
- mptcp:
- use mptcp_schedule_work instead of open-coding it and make the
worker check stricter, to avoid scheduling work on closed
sockets
- fix NULL pointer dereference on fastopen early fallback
- skbuff: fix memory corruption due to a race between skb coalescing
and releasing clones confusing page_pool reference counting
- bonding: fix neighbor solicitation validation on backup slaves
- bpf: tcp: use sock_gen_put instead of sock_put in bpf_iter_tcp
- bpf: arm64: fixed a BTI error on returning to patched function
- openvswitch: fix race on port output leading to inf loop
- sfp: initialize sfp->i2c_block_size at sfp allocation to avoid
returning a different errno than expected
- phy: nxp-c45-tja11xx: unregister PTP, purge queues on remove
- Bluetooth: fix printing errors if LE Connection times out
- Bluetooth: assorted UaF, deadlock and data race fixes
- eth: macb: fix memory corruption in extended buffer descriptor mode
Misc:
- adjust the XDP Rx flow hash API to also include the protocol layers
over which the hash was computed"
* tag 'net-6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (50 commits)
selftests/bpf: Adjust bpf_xdp_metadata_rx_hash for new arg
mlx4: bpf_xdp_metadata_rx_hash add xdp rss hash type
veth: bpf_xdp_metadata_rx_hash add xdp rss hash type
mlx5: bpf_xdp_metadata_rx_hash add xdp rss hash type
xdp: rss hash types representation
selftests/bpf: xdp_hw_metadata remove bpf_printk and add counters
skbuff: Fix a race between coalescing and releasing SKBs
net: macb: fix a memory corruption in extended buffer descriptor mode
selftests: add the missing CONFIG_IP_SCTP in net config
udp6: fix potential access to stale information
selftests: openvswitch: adjust datapath NL message declaration
selftests: mptcp: userspace pm: uniform verify events
mptcp: fix NULL pointer dereference on fastopen early fallback
mptcp: stricter state check in mptcp_worker
mptcp: use mptcp_schedule_work instead of open-coding it
net: enetc: workaround for unresponsive pMAC after receiving express traffic
sctp: fix a potential overflow in sctp_ifwdtsn_skip
net: qrtr: Fix an uninit variable access bug in qrtr_tx_resume()
rtnetlink: Restore RTM_NEW/DELLINK notification behavior
net: ti/cpsw: Add explicit platform_device.h and of_platform.h includes
...
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git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
Pull pci fixes from Bjorn Helgaas:
- Provide pci_msix_can_alloc_dyn() stub when CONFIG_PCI_MSI unset to
avoid build errors (Reinette Chatre)
- Quirk AMD XHCI controller that loses MSI-X state in D3hot to avoid
broken USB after hotplug or suspend/resume (Basavaraj Natikar)
- Fix use-after-free in pci_bus_release_domain_nr() (Rob Herring)
* tag 'pci-v6.3-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
PCI: Fix use-after-free in pci_bus_release_domain_nr()
x86/PCI: Add quirk for AMD XHCI controller that loses MSI-X state in D3hot
PCI/MSI: Provide missing stub for pci_msix_can_alloc_dyn()
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Pull kvm fixes from Paolo Bonzini:
"Two ARM fixes:
- Ensure the guest PMU context is restored before the first KVM_RUN,
fixing an issue where EL0 event counting is broken after vCPU
save/restore
- Actually initialize ID_AA64PFR0_EL1.{CSV2,CSV3} based on the
sanitized, system-wide values for protected VMs"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: arm64: Advertise ID_AA64PFR0_EL1.CSV2/3 to protected VMs
KVM: arm64: PMU: Restore the guest's EL0 event counting after migration
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git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull UML fix from Richard Weinberger:
- Build regression fix for older gcc versions
* tag 'uml-for-linus-6.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
um: Only disable SSE on clang to work around old GCC bugs
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Add a new Intel Arrow Lake CPU model number
- Fix a confusion about how to check the version of the ACPI spec which
supports a "online capable" bit in the MADT table which lead to a
bunch of boot breakages with Zen1 systems and VMs
* tag 'x86_urgent_for_v6.3_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add model number for Intel Arrow Lake processor
x86/acpi/boot: Correct acpi_is_processor_usable() check
x86/ACPI/boot: Use FADT version to check support for online capable
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https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:
====================
pull-request: bpf 2023-04-08
We've added 4 non-merge commits during the last 11 day(s) which contain
a total of 5 files changed, 39 insertions(+), 6 deletions(-).
The main changes are:
1) Fix BPF TCP socket iterator to use correct helper for dropping
socket's refcount, that is, sock_gen_put instead of sock_put,
from Martin KaFai Lau.
2) Fix a BTI exception splat in BPF trampoline-generated code on arm64,
from Xu Kuohai.
3) Fix a LongArch JIT error from missing BPF_NOSPEC no-op, from George Guo.
4) Fix dynamic XDP feature detection of veth in xdp_redirect selftest,
from Lorenzo Bianconi.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: fix xdp_redirect xdp-features selftest for veth driver
bpf, arm64: Fixed a BTI error on returning to patched function
LoongArch, bpf: Fix jit to skip speculation barrier opcode
bpf: tcp: Use sock_gen_put instead of sock_put in bpf_iter_tcp
====================
Link: https://lore.kernel.org/r/20230407224642.30906-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fix from Catalin Marinas:
"Fix uninitialised variable warning (from smatch) in the arm64 compat
alignment fixup code"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: compat: Work around uninitialized variable warning
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The AMD [1022:15b8] USB controller loses some internal functional MSI-X
context when transitioning from D0 to D3hot. BIOS normally traps D0->D3hot
and D3hot->D0 transitions so it can save and restore that internal context,
but some firmware in the field can't do this because it fails to clear the
AMD_15B8_RCC_DEV2_EPF0_STRAP2 NO_SOFT_RESET bit.
Clear AMD_15B8_RCC_DEV2_EPF0_STRAP2 NO_SOFT_RESET bit before USB controller
initialization during boot.
Link: https://lore.kernel.org/linux-usb/Y%2Fz9GdHjPyF2rNG3@glanzmann.de/T/#u
Link: https://lore.kernel.org/r/20230329172859.699743-1-Basavaraj.Natikar@amd.com
Reported-by: Thomas Glanzmann <thomas@glanzmann.de>
Tested-by: Thomas Glanzmann <thomas@glanzmann.de>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Cc: stable@vger.kernel.org
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Conflicts:
drivers/net/ethernet/google/gve/gve.h
3ce934558097 ("gve: Secure enough bytes in the first TX desc for all TCP pkts")
75eaae158b1b ("gve: Add XDP DROP and TX support for GQI-QPL format")
https://lore.kernel.org/all/20230406104927.45d176f5@canb.auug.org.au/
https://lore.kernel.org/all/c5872985-1a95-0bc8-9dcc-b6f23b439e9d@tessares.net/
Adjacent changes:
net/can/isotp.c
051737439eae ("can: isotp: fix race between isotp_sendsmg() and isotp_release()")
96d1c81e6a04 ("can: isotp: add module parameter for maximum pdu size")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 fixes for 6.3, part #3
- Ensure the guest PMU context is restored before the first KVM_RUN,
fixing an issue where EL0 event counting is broken after vCPU
save/restore
- Actually initialize ID_AA64PFR0_EL1.{CSV2,CSV3} based on the
sanitized, system-wide values for protected VMs
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git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next
Marc Kleine-Budde says:
====================
pull-request: can-next 2023-04-04-2
The first patch is by Oliver Hartkopp and makes the maximum pdu size
of the CAN ISOTP protocol configurable.
The following 5 patches are by Dario Binacchi and add support for the
bxCAN controller by ST.
Geert Uytterhoeven's patch for the rcar_canfd driver fixes a sparse
warning.
Peng Fan's patch adds an optional power-domains property to the
flexcan device tree binding.
Frank Jungclaus adds support for CAN_CTRLMODE_BERR_REPORTING to the
esd_usb driver.
The last patch is by Oliver Hartkopp and converts the USB IDs of the
kvaser_usb driver to hexadecimal values.
* tag 'linux-can-next-for-6.4-20230404-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next:
kvaser_usb: convert USB IDs to hexadecimal values
can: esd_usb: Add support for CAN_CTRLMODE_BERR_REPORTING
dt-bindings: can: fsl,flexcan: add optional power-domains property
can: rcar_canfd: rcar_canfd_probe(): fix plain integer in transceivers[] init
can: bxcan: add support for ST bxCAN controller
ARM: dts: stm32: add pin map for CAN controller on stm32f4
ARM: dts: stm32: add CAN support on stm32f429
dt-bindings: net: can: add STM32 bxcan DT bindings
dt-bindings: arm: stm32: add compatible for syscon gcan node
can: isotp: add module parameter for maximum pdu size
====================
Link: https://lore.kernel.org/r/20230404145908.1714400-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Dan reports that smatch complains about a potential uninitialized
variable being used in the compat alignment fixup code.
The logic is not wrong per se, but we do end up using an uninitialized
variable if reading the instruction that triggered the alignment fault
from user space faults, even if the fault ensures that the uninitialized
value doesn't propagate any further.
Given that we just give up and return 1 if any fault occurs when reading
the instruction, let's get rid of the 'success handling' pattern that
captures the fault in a variable and aborts later, and instead, just
return 1 immediately if any of the get_user() calls result in an
exception.
Fixes: 3fc24ef32d3b ("arm64: compat: Implement misalignment fixups for multiword loads")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/202304021214.gekJ8yRc-lkp@intel.com/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20230404103625.2386382-1-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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Successor to Lunar Lake.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230404174641.426593-1-tony.luck@intel.com
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Pull kvm fixes from Paolo Bonzini:
"PPC:
- Hide KVM_CAP_IRQFD_RESAMPLE if XIVE is enabled
s390:
- Fix handling of external interrupts in protected guests
x86:
- Resample the pending state of IOAPIC interrupts when unmasking them
- Fix usage of Hyper-V "enlightened TLB" on AMD
- Small fixes to real mode exceptions
- Suppress pending MMIO write exits if emulator detects exception
Documentation:
- Fix rST syntax"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
docs: kvm: x86: Fix broken field list
KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent
KVM: s390: pv: fix external interruption loop not always detected
KVM: nVMX: Do not report error code when synthesizing VM-Exit from Real Mode
KVM: x86: Clear "has_error_code", not "error_code", for RM exception injection
KVM: x86: Suppress pending MMIO write exits if emulator detects exception
KVM: x86/ioapic: Resample the pending state of an IRQ when unmasking
KVM: irqfd: Make resampler_list an RCU list
KVM: SVM: Flush Hyper-V TLB when required
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The existing pKVM code attempts to advertise CSV2/3 using values
initialized to 0, but never set. To advertise CSV2/3 to protected
guests, pass the CSV2/3 values to hyp when initializing hyp's
view of guests' ID_AA64PFR0_EL1.
Similar to non-protected KVM, these are system-wide, rather than
per cpu, for simplicity.
Fixes: 6c30bfb18d0b ("KVM: arm64: Add handlers for protected VM System Registers")
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20230404152321.413064-1-tabba@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
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As part of the Rust support for UML, we disable SSE (and similar flags)
to match the normal x86 builds. This both makes sense (we ideally want a
similar configuration to x86), and works around a crash bug with SSE
generation under Rust with LLVM.
However, this breaks compiling stdlib.h under gcc < 11, as the x86_64
ABI requires floating-point return values be stored in an SSE register.
gcc 11 fixes this by only doing register allocation when a function is
actually used, and since we never use atof(), it shouldn't be a problem:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99652
Nevertheless, only disable SSE on clang setups, as that's a simple way
of working around everyone's bugs.
Fixes: 884981867947 ("rust: arch/um: Disable FP/SIMD instruction to match x86")
Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
Link: https://lore.kernel.org/linux-um/6df2ecef9011d85654a82acd607fdcbc93ad593c.camel@huaweicloud.com/
Tested-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
Tested-by: SeongJae Park <sj@kernel.org>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Tested-by: Arthur Grillo <arthurgrillo@riseup.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
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git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv fixes from Wei Liu:
- Fix a bug in channel allocation for VMbus (Mohammed Gamal)
- Do not allow root partition functionality in CVM (Michael Kelley)
* tag 'hyperv-fixes-signed-20230402' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
x86/hyperv: Block root partition functionality in a Confidential VM
Drivers: vmbus: Check for channel allocation before looking up relids
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When BPF_TRAMP_F_CALL_ORIG is set, BPF trampoline uses BLR to jump
back to the instruction next to call site to call the patched function.
For BTI-enabled kernel, the instruction next to call site is usually
PACIASP, in this case, it's safe to jump back with BLR. But when
the call site is not followed by a PACIASP or bti, a BTI exception
is triggered.
Here is a fault log:
Unhandled 64-bit el1h sync exception on CPU0, ESR 0x0000000034000002 -- BTI
CPU: 0 PID: 263 Comm: test_progs Tainted: GF
Hardware name: linux,dummy-virt (DT)
pstate: 40400805 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=-c)
pc : bpf_fentry_test1+0xc/0x30
lr : bpf_trampoline_6442573892_0+0x48/0x1000
sp : ffff80000c0c3a50
x29: ffff80000c0c3a90 x28: ffff0000c2e6c080 x27: 0000000000000000
x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000050
x23: 0000000000000000 x22: 0000ffffcfd2a7f0 x21: 000000000000000a
x20: 0000ffffcfd2a7f0 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffffcfd2a7f0
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: ffff80000914f5e4 x9 : ffff8000082a1528
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0101010101010101
x5 : 0000000000000000 x4 : 00000000fffffff2 x3 : 0000000000000001
x2 : ffff8001f4b82000 x1 : 0000000000000000 x0 : 0000000000000001
Kernel panic - not syncing: Unhandled exception
CPU: 0 PID: 263 Comm: test_progs Tainted: GF
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0xec/0x144
show_stack+0x24/0x7c
dump_stack_lvl+0x8c/0xb8
dump_stack+0x18/0x34
panic+0x1cc/0x3ec
__el0_error_handler_common+0x0/0x130
el1h_64_sync_handler+0x60/0xd0
el1h_64_sync+0x78/0x7c
bpf_fentry_test1+0xc/0x30
bpf_fentry_test1+0xc/0x30
bpf_prog_test_run_tracing+0xdc/0x2a0
__sys_bpf+0x438/0x22a0
__arm64_sys_bpf+0x30/0x54
invoke_syscall+0x78/0x110
el0_svc_common.constprop.0+0x6c/0x1d0
do_el0_svc+0x38/0xe0
el0_svc+0x30/0xd0
el0t_64_sync_handler+0x1ac/0x1b0
el0t_64_sync+0x1a0/0x1a4
Kernel Offset: disabled
CPU features: 0x0000,00034c24,f994fdab
Memory Limit: none
And the instruction next to call site of bpf_fentry_test1 is ADD,
not PACIASP:
<bpf_fentry_test1>:
bti c
nop
nop
add w0, w0, #0x1
paciasp
For BPF prog, JIT always puts a PACIASP after call site for BTI-enabled
kernel, so there is no problem. To fix it, replace BLR with RET to bypass
the branch target check.
Fixes: efc9909fdce0 ("bpf, arm64: Add bpf trampoline for arm64")
Reported-by: Florent Revest <revest@chromium.org>
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Florent Revest <revest@chromium.org>
Acked-by: Florent Revest <revest@chromium.org>
Link: https://lore.kernel.org/bpf/20230401234144.3719742-1-xukuohai@huaweicloud.com
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fix a false positive warning in __pte_needs_flush() (with DEBUG_VM=y)
- Fix oops when a PF_IO_WORKER thread tries to core dump
- Don't try to reconfigure VAS when it's disabled
Thanks to Benjamin Gray, Haren Myneni, Jens Axboe, Nathan Lynch, and
Russell Currey.
* tag 'powerpc-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/pseries/vas: Ignore VAS update for DLPAR if copy/paste is not enabled
powerpc: Don't try to copy PPR for task with NULL pt_regs
powerpc/64s: Fix __pte_needs_flush() false positive warning
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git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:
- A fix for FPU probing in XIP kernels
- Always enable the alternative framework for non-XIP kernels
* tag 'riscv-for-linus-6.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
RISC-V: always select RISCV_ALTERNATIVE for non-xip kernels
RISC-V: add non-alternative fallback for riscv_has_extension_[un]likely()
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git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS fix from Thomas Bogendoerfer:
"Fix to avoid crash on BCM6358 platforms"
* tag 'mips-fixes_6.3_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
mips: bmips: BCM6358: disable RAC flush for TP1
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When introduced, IRQFD resampling worked on POWER8 with XICS. However
KVM on POWER9 has never implemented it - the compatibility mode code
("XICS-on-XIVE") misses the kvm_notify_acked_irq() call and the native
XIVE mode does not handle INTx in KVM at all.
This moved the capability support advertising to platforms and stops
advertising it on XIVE, i.e. POWER9 and later.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Anup Patel <anup@brainfault.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20220504074807.3616813-1-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
A small fix that repairs the external loop detection code for PV
guests.
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Conflicts:
drivers/net/ethernet/mediatek/mtk_ppe.c
3fbe4d8c0e53 ("net: ethernet: mtk_eth_soc: ppe: add support for flow accounting")
924531326e2d ("net: ethernet: mtk_eth_soc: add missing ppe cache flush when deleting a flow")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The logic in acpi_is_processor_usable() requires the online capable
bit be set for hotpluggable CPUs. The online capable bit has been
introduced in ACPI 6.3.
However, for ACPI revisions < 6.3 which do not support that bit, CPUs
should be reported as usable, not the other way around.
Reverse the check.
[ bp: Rewrite commit message. ]
Fixes: e2869bd7af60 ("x86/acpi/boot: Do not register processors that cannot be onlined for x2APIC")
Suggested-by: Miguel Luis <miguel.luis@oracle.com>
Suggested-by: Boris Ostrovsky <boris.ovstrosky@oracle.com>
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: David R <david@unsolicited.net>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230327191026.3454-2-eric.devolder@oracle.com
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ACPI 6.3 introduced the online capable bit, and also introduced MADT
version 5.
Latter was used to distinguish whether the offset storing online capable
could be used. However ACPI 6.2b has MADT version "45" which is for
an errata version of the ACPI 6.2 spec. This means that the Linux code
for detecting availability of MADT will mistakenly flag ACPI 6.2b as
supporting online capable which is inaccurate as it's an ACPI 6.3 feature.
Instead use the FADT major and minor revision fields to distinguish this.
[ bp: Massage. ]
Fixes: aa06e20f1be6 ("x86/ACPI: Don't add CPUs that are not online capable")
Reported-by: Eric DeVolder <eric.devolder@oracle.com>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/943d2445-84df-d939-f578-5d8240d342cc@unsolicited.net
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Currently, with VHE, KVM enables the EL0 event counting for the
guest on vcpu_load() or KVM enables it as a part of the PMU
register emulation process, when needed. However, in the migration
case (with VHE), the same handling is lacking, as vPMU register
values that were restored by userspace haven't been propagated yet
(the PMU events haven't been created) at the vcpu load-time on the
first KVM_RUN (kvm_vcpu_pmu_restore_guest() called from vcpu_load()
on the first KVM_RUN won't do anything as events_{guest,host} of
kvm_pmu_events are still zero).
So, with VHE, enable the guest's EL0 event counting on the first
KVM_RUN (after the migration) when needed. More specifically,
have kvm_pmu_handle_pmcr() call kvm_vcpu_pmu_restore_guest()
so that kvm_pmu_handle_pmcr() on the first KVM_RUN can take
care of it.
Fixes: d0c94c49792c ("KVM: arm64: Restore PMU configuration on first run")
Cc: stable@vger.kernel.org
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Reiji Watanabe <reijiw@google.com>
Link: https://lore.kernel.org/r/20230329023944.2488484-1-reijiw@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
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alternative dependency"
Conor Dooley <conor.dooley@microchip.com> says:
Here's my attempt at fixing both the use of an FPU on XIP kernels and
the issue that Jason ran into where CONFIG_FPU, which needs the
alternatives frame work for has_fpu() checks, could be enabled without
the alternatives actually being present.
For the former, a "slow" fallback that does not use alternatives is
added to riscv_has_extension_[un]likely() that can be used with XIP.
Obviously, we want to make use of Jisheng's alternatives based approach
where possible, so any users of riscv_has_extension_[un]likely() will
want to make sure that they select RISCV_ALTERNATIVE.
If they don't however, they'll hit the fallback path which (should,
sparing a silly mistake from me!) behave in the same way, thus
succeeding silently. Sounds like a
To prevent "depends on !XIP_KERNEL; select RISCV_ALTERNATIVE" spreading
like the plague through the various places that want to check for the
presence of extensions, and sidestep the potential silent "success"
mentioned above, all users RISCV_ALTERNATIVE are converted from selects
to dependencies, with the option being selected for all !XIP_KERNEL
builds.
I know that the VDSO was a key place that Jisheng wanted to use the new
helper rather than static branches, and I think the fallback path
should not cause issues there.
See the thread at [1] for the prior discussion.
1 - https://lore.kernel.org/linux-riscv/20230128172856.3814-1-jszhang@kernel.org/T/#m21390d570997145d31dd8bb95002fd61f99c6573
[Palmer: merging in the fixes as a branch as there's some features that
depend on it.]
* b4-shazam-merge:
RISC-V: always select RISCV_ALTERNATIVE for non-xip kernels
RISC-V: add non-alternative fallback for riscv_has_extension_[un]likely()
Link: https://lore.kernel.org/r/20230324100538.3514663-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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When moving switch_to's has_fpu() over to using
riscv_has_extension_likely() rather than static branches, the FPU code
gained a dependency on the alternatives framework.
That dependency has now been removed, as riscv_has_extension_ikely() now
contains a fallback path, using __riscv_isa_extension_available(), but
if CONFIG_RISCV_ALTERNATIVE isn't selected when CONFIG_FPU is, has_fpu()
checks will not benefit from the "fast path" that the alternatives
framework provides.
We want to ensure that alternatives are available whenever
riscv_has_extension_[un]likely() is used, rather than silently falling
back to the slow path, but rather than rely on selecting
RISCV_ALTERNATIVE in the myriad of locations that may use
riscv_has_extension_[un]likely(), select it (almost) always instead by
adding it to the main RISCV config entry.
xip kernels cannot make use of the alternatives framework, so it is not
enabled for those configurations, although this is the status quo.
All current sites that select RISCV_ALTERNATIVE are converted to
dependencies on the option instead. The explicit dependencies on
!XIP_KERNEL can be dropped, as RISCV_ALTERNATIVE is not user selectable.
Fixes: 702e64550b12 ("riscv: fpu: switch has_fpu() to riscv_has_extension_likely()")
Link: https://lore.kernel.org/all/ZBruFRwt3rUVngPu@zx2c4.com/
Reported-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20230324100538.3514663-3-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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The has_fpu() check, which in turn calls riscv_has_extension_likely(),
relies on alternatives to figure out whether the system has an FPU.
As a result, it will malfunction on XIP kernels, as they do not support
the alternatives mechanism.
When alternatives support is not present, fall back to using
__riscv_isa_extension_available() in riscv_has_extension_[un]likely()
instead stead, which handily takes the same argument, so that kernels
that do not support alternatives can accurately report the presence of
FPU support.
Fixes: 702e64550b12 ("riscv: fpu: switch has_fpu() to riscv_has_extension_likely()")
Link: https://lore.kernel.org/all/ad445951-3d13-4644-94d9-e0989cda39c3@spud/
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20230324100538.3514663-2-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Pull xtensa fixes from Max Filippov:
- fix KASAN report in show_stack
- drop linux-xtensa mailing list from the MAINTAINERS file
* tag 'xtensa-20230327' of https://github.com/jcmvbkbc/linux-xtensa:
MAINTAINERS: xtensa: drop linux-xtensa@linux-xtensa.org mailing list
xtensa: fix KASAN report for show_stack
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The hypervisor supports user-mode NX from Power10.
pseries_vas_dlpar_cpu() is called from lparcfg_write() to update VAS
windows for DLPAR event in shared processor mode and the kernel gets
-ENOTSUPP for HCALLs if the user-mode NX is not supported. The current
VAS implementation also supports only with Radix page tables. Whereas in
dedicated processor mode, pseries_vas_notifier() is registered only if
the copy/paste feature is enabled. So instead of displaying HCALL error
messages, update VAS capabilities if the copy/paste feature is
available.
This patch ignores updating VAS capabilities in pseries_vas_dlpar_cpu()
and returns success if the copy/paste feature is not enabled. Then
lparcfg_write() completes the processor DLPAR operations without any
failures.
Fixes: 2147783d6bf0 ("powerpc/pseries: Use lparcfg to reconfig VAS windows for DLPAR CPU")
Cc: stable@vger.kernel.org # v6.1+
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/1d0e727e7dbd9a28627ef08ca9df9c86a50175e2.camel@linux.ibm.com
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git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Vasily Gorbik:
- Fix an error handling issue with PTRACE_GET_LAST_BREAK request so
that -EFAULT is returned if put_user() fails, instead of ignoring it
- Fix a build race for the modules_prepare target when
CONFIG_EXPOLINE_EXTERN is enabled by reintroducing the dependence on
scripts
- Fix a memory leak in vfio_ap device driver
- Add missing earlyclobber annotations to __clear_user() inline
assembly to prevent incorrect register allocation
* tag 's390-6.3-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/ptrace: fix PTRACE_GET_LAST_BREAK error handling
s390: reintroduce expoline dependence to scripts
s390/vfio-ap: fix memory leak in vfio_ap device driver
s390/uaccess: add missing earlyclobber annotations to __clear_user()
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powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which
from my (arguably very short) checking is not commonly done for other
archs. This is fine, except when PF_IO_WORKER's have been created and
the task does something that causes a coredump to be generated. Then we
get this crash:
Kernel attempted to read user page (160) - exploit attempt? (uid: 1000)
BUG: Kernel NULL pointer dereference on read at 0x00000160
Faulting instruction address: 0xc0000000000c3a60
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries
Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod
CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88
Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
NIP: c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0
REGS: c0000000041833b0 TRAP: 0300 Not tainted (6.3.0-rc2+)
MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88082828 XER: 200400f8
...
NIP memcpy_power7+0x200/0x7d0
LR ppr_get+0x64/0xb0
Call Trace:
ppr_get+0x40/0xb0 (unreliable)
__regset_get+0x180/0x1f0
regset_get_alloc+0x64/0x90
elf_core_dump+0xb98/0x1b60
do_coredump+0x1c34/0x24a0
get_signal+0x71c/0x1410
do_notify_resume+0x140/0x6f0
interrupt_exit_user_prepare_main+0x29c/0x320
interrupt_exit_user_prepare+0x6c/0xa0
interrupt_return_srr_user+0x8/0x138
Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL
pt_regs.
Check for a valid pt_regs in both ppc_get/ppr_set, and return an error
if not set. The actual error value doesn't seem to be important here, so
just pick -EINVAL.
Fixes: fa439810cc1b ("powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[mpe: Trim oops in change log, add Fixes & Cc stable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/d9f63344-fe7c-56ae-b420-4a1a04a2ae4c@kernel.dk
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Userspace PROT_NONE ptes set _PAGE_PRIVILEGED, triggering a false
positive debug assertion that __pte_flags_need_flush() is not called
on a kernel mapping.
Detect when it is a userspace PROT_NONE page by checking the required
bits of PAGE_NONE are set, and none of the RWX bits are set.
pte_protnone() is insufficient here because it always returns 0 when
CONFIG_NUMA_BALANCING=n.
Fixes: b11931e9adc1 ("powerpc/64s: add pte_needs_flush and huge_pmd_needs_flush")
Cc: stable@vger.kernel.org # v6.1+
Reported-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230302225947.81083-1-bgray@linux.ibm.com
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Add pin configurations for using CAN controller on stm32f469-disco
board. They are located on the Arduino compatible connector CN5 (CAN1)
and on the extension connector CN12 (CAN2).
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20230328073328.3949796-5-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Add support for bxcan (Basic eXtended CAN controller) to STM32F429. The
chip contains two CAN peripherals, CAN1 the primary and CAN2 the secondary,
that share some of the required logic like clock and filters. This means
that the secondary CAN can't be used without the primary CAN.
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/all/20230328073328.3949796-4-dario.binacchi@amarulasolutions.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Just skip the opcode(BPF_ST | BPF_NOSPEC) in the BPF JIT instead of
failing to JIT the entire program, given LoongArch currently has no
couterpart of a speculation barrier instruction. To verify the issue,
use the ltp testcase as shown below.
Also, Wang says:
I can confirm there's currently no speculation barrier equivalent
on LonogArch. (Loongson says there are builtin mitigations for
Spectre-V1 and V2 on their chips, and AFAIK efforts to port the
exploits to mips/LoongArch have all failed a few years ago.)
Without this patch:
$ ./bpf_prog02
[...]
bpf_common.c:123: TBROK: Failed verification: ??? (524)
[...]
Summary:
passed 0
failed 0
broken 1
skipped 0
warnings 0
With this patch:
$ ./bpf_prog02
[...]
Summary:
passed 0
failed 0
broken 0
skipped 0
warnings 0
Fixes: 5dc615520c4d ("LoongArch: Add BPF JIT support")
Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: WANG Xuerui <git@xen0n.name>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/bpf/20230328071335.2664966-1-guodongtai@kylinos.cn
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To determine whether the guest has caused an external interruption loop
upon code 20 (external interrupt) intercepts, the ext_new_psw needs to
be inspected to see whether external interrupts are enabled.
Under non-PV, ext_new_psw can simply be taken from guest lowcore. Under
PV, KVM can only access the encrypted guest lowcore and hence the
ext_new_psw must not be taken from guest lowcore.
handle_external_interrupt() incorrectly did that and hence was not able
to reliably tell whether an external interruption loop is happening or
not. False negatives cause spurious failures of my kvm-unit-test
for extint loops[1] under PV.
Since code 20 is only caused under PV if and only if the guest's
ext_new_psw is enabled for external interrupts, false positive detection
of a external interruption loop can not happen.
Fix this issue by instead looking at the guest PSW in the state
description. Since the PSW swap for external interrupt is done by the
ultravisor before the intercept is caused, this reliably tells whether
the guest is enabled for external interrupts in the ext_new_psw.
Also update the comments to explain better what is happening.
[1] https://lore.kernel.org/kvm/20220812062151.1980937-4-nrb@linux.ibm.com/
Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Fixes: 201ae986ead7 ("KVM: s390: protvirt: Implement interrupt injection")
Link: https://lore.kernel.org/r/20230213085520.100756-2-nrb@linux.ibm.com
Message-Id: <20230213085520.100756-2-nrb@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
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Pull kvm fixes from Paolo Bonzini:
"RISC-V:
- Fix VM hang in case of timer delta being zero
ARM:
- MMU fixes:
- Read the MMU notifier seq before dropping the mmap lock to guard
against reading a potentially stale VMA
- Disable interrupts when walking user page tables to protect
against the page table being freed
- Read the MTE permissions for the VMA within the mmap lock
critical section, avoiding the use of a potentally stale VMA
pointer
- vPMU fixes:
- Return the sum of the current perf event value and PMC snapshot
for reads from userspace
- Don't save the value of guest writes to PMCR_EL0.{C,P}, which
could otherwise lead to userspace erroneously resetting the vPMU
during VM save/restore"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
riscv/kvm: Fix VM hang in case of timer delta being zero.
KVM: arm64: Check for kvm_vma_mte_allowed in the critical section
KVM: arm64: Disable interrupts while walking userspace PTs
KVM: arm64: Retry fault if vma_lookup() results become invalid
KVM: arm64: PMU: Don't save PMCR_EL0.{C,P} for the vCPU
KVM: arm64: PMU: Fix GET_ONE_REG for vPMC regs to return the current value
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Return -EFAULT if put_user() for the PTRACE_GET_LAST_BREAK
request fails, instead of silently ignoring it.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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Expolines depend on scripts/basic/fixdep. And build of expolines can now
race with the fixdep build:
make[1]: *** Deleting file 'arch/s390/lib/expoline/expoline.o'
/bin/sh: line 1: scripts/basic/fixdep: Permission denied
make[1]: *** [../scripts/Makefile.build:385: arch/s390/lib/expoline/expoline.o] Error 126
make: *** [../arch/s390/Makefile:166: expoline_prepare] Error 2
The dependence was removed in the below Fixes: commit. So reintroduce
the dependence on scripts.
Fixes: a0b0987a7811 ("s390/nospec: remove unneeded header includes")
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: stable@vger.kernel.org
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230316112809.7903-1-jirislaby@kernel.org
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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Add missing earlyclobber annotation to size, to, and tmp2 operands of the
__clear_user() inline assembly since they are modified or written to before
the last usage of all input operands. This can lead to incorrect register
allocation for the inline assembly.
Fixes: 6c2a9e6df604 ("[S390] Use alternative user-copy operations for new hardware.")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/all/20230321122514.1743889-3-mark.rutland@arm.com/
Cc: stable@vger.kernel.org
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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Don't report an error code to L1 when synthesizing a nested VM-Exit and
L2 is in Real Mode. Per Intel's SDM, regarding the error code valid bit:
This bit is always 0 if the VM exit occurred while the logical processor
was in real-address mode (CR0.PE=0).
The bug was introduced by a recent fix for AMD's Paged Real Mode, which
moved the error code suppression from the common "queue exception" path
to the "inject exception" path, but missed VMX's "synthesize VM-Exit"
path.
Fixes: b97f07458373 ("KVM: x86: determine if an exception has an error code only when injecting it.")
Cc: stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230322143300.2209476-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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When injecting an exception into a vCPU in Real Mode, suppress the error
code by clearing the flag that tracks whether the error code is valid, not
by clearing the error code itself. The "typo" was introduced by recent
fix for SVM's funky Paged Real Mode.
Opportunistically hoist the logic above the tracepoint so that the trace
is coherent with respect to what is actually injected (this was also the
behavior prior to the buggy commit).
Fixes: b97f07458373 ("KVM: x86: determine if an exception has an error code only when injecting it.")
Cc: stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230322143300.2209476-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Clear vcpu->mmio_needed when injecting an exception from the emulator to
squash a (legitimate) warning about vcpu->mmio_needed being true at the
start of KVM_RUN without a callback being registered to complete the
userspace MMIO exit. Suppressing the MMIO write exit is inarguably wrong
from an architectural perspective, but it is the least awful hack-a-fix
due to shortcomings in KVM's uAPI, not to mention that KVM already
suppresses MMIO writes in this scenario.
Outside of REP string instructions, KVM doesn't provide a way to resume
an instruction at the exact point where it was "interrupted" if said
instruction partially completed before encountering an MMIO access. For
MMIO reads, KVM immediately exits to userspace upon detecting MMIO as
userspace provides the to-be-read value in a buffer, and so KVM can safely
(more or less) restart the instruction from the beginning. When the
emulator re-encounters the MMIO read, KVM will service the MMIO by getting
the value from the buffer instead of exiting to userspace, i.e. KVM won't
put the vCPU into an infinite loop.
On an emulated MMIO write, KVM finishes the instruction before exiting to
userspace, as exiting immediately would ultimately hang the vCPU due to
the aforementioned shortcoming of KVM not being able to resume emulation
in the middle of an instruction.
For the vast majority of _emulated_ instructions, deferring the userspace
exit doesn't cause problems as very few x86 instructions (again ignoring
string operations) generate multiple writes. But for instructions that
generate multiple writes, e.g. PUSHA (multiple pushes onto the stack),
deferring the exit effectively results in only the final write triggering
an exit to userspace. KVM does support multiple MMIO "fragments", but
only for page splits; if an instruction performs multiple distinct MMIO
writes, the number of fragments gets reset when the next MMIO write comes
along and any previous MMIO writes are dropped.
Circling back to the warning, if a deferred MMIO write coincides with an
exception, e.g. in this case a #SS due to PUSHA underflowing the stack
after queueing a write to an MMIO page on a previous push, KVM injects
the exceptions and leaves the deferred MMIO pending without registering a
callback, thus triggering the splat.
Sweep the problem under the proverbial rug as dropping MMIO writes is not
unique to the exception scenario (see above), i.e. instructions like PUSHA
are fundamentally broken with respect to MMIO, and have been since KVM's
inception.
Reported-by: zhangjianguo <zhangjianguo18@huawei.com>
Reported-by: syzbot+760a73552f47a8cd0fd9@syzkaller.appspotmail.com
Reported-by: syzbot+8accb43ddc6bd1f5713a@syzkaller.appspotmail.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230322141220.2206241-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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