Adding overlays for PiFi DAC Zero and PiFi DAC HD.

Signed-off-by: David Knell <david.knell@gmail.com>

commit d11a1d08 upstream.

If the maximum performance level taken for computing the
arch_max_freq_ratio value used in the x86 scale-invariance code is
higher than the one corresponding to the cpuinfo.max_freq value
coming from the acpi_cpufreq driver, the scale-invariant utilization
falls below 100% even if the CPU runs at cpuinfo.max_freq or slightly
faster, which causes the schedutil governor to select a frequency
below cpuinfo.max_freq.  That frequency corresponds to a frequency
table entry below the maximum performance level necessary to get to
the "boost" range of CPU frequencies which prevents "boost"
frequencies from being used in some workloads.

While this issue is related to scale-invariance, it may be amplified
by commit db865272 ("cpufreq: Avoid configuring old governors as
default with intel_pstate") from the 5.10 development cycle which
made it extremely easy to default to schedutil even if the preferred
driver is acpi_cpufreq as long as intel_pstate is built too, because
the mere presence of the latter effectively removes the ondemand
governor from the defaults.  Distro kernels are likely to include
both intel_pstate and acpi_cpufreq on x86, so their users who cannot
use intel_pstate or choose to use acpi_cpufreq may easily be
affectecd by this issue.

If CPPC is available, it can be used to address this issue by
extending the frequency tables created by acpi_cpufreq to cover the
entire available frequency range (including "boost" frequencies) for
each CPU, but if CPPC is not there, acpi_cpufreq has no idea what
the maximum "boost" frequency is and the frequency tables created by
it cannot be extended in a meaningful way, so in that case make it
ask the arch scale-invariance code to to use the "nominal" performance
level for CPU utilization scaling in order to avoid the issue at hand.

Fixes: db865272

 ("cpufreq: Avoid configuring old governors as default with intel_pstate")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 68d54cee

 upstream.

The ptrace(PTRACE_PEEKMTETAGS) implementation checks whether the user
page has valid tags (mapped with PROT_MTE) by testing the PG_mte_tagged
page flag. If this bit is cleared, ptrace(PTRACE_PEEKMTETAGS) returns
-EIO.

A newly created (PROT_MTE) mapping points to the zero page which had its
tags zeroed during cpu_enable_mte(). If there were no prior writes to
this mapping, ptrace(PTRACE_PEEKMTETAGS) fails with -EIO since the zero
page does not have the PG_mte_tagged flag set.

Set PG_mte_tagged on the zero page when its tags are cleared during
boot. In addition, to avoid ptrace(PTRACE_PEEKMTETAGS) succeeding on
!PROT_MTE mappings pointing to the zero page, change the
__access_remote_tags() check to (vm_flags & VM_MTE) instead of
PG_mte_tagged.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fixes: 34bfeea4

 ("arm64: mte: Clear the tags when a page is mapped in user-space with PROT_MTE")
Cc: <stable@vger.kernel.org> # 5.10.x
Cc: Will Deacon <will@kernel.org>
Reported-by: Luis Machado <luis.machado@linaro.org>
Tested-by: Luis Machado <luis.machado@linaro.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20210210180316.23654-1-catalin.marinas@arm.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 70245f86 upstream.

Invoking x86_init.irqs.create_pci_msi_domain() before
x86_init.pci.arch_init() breaks XEN PV.

The XEN_PV specific pci.arch_init() function overrides the default
create_pci_msi_domain() which is obviously too late.

As a consequence the XEN PV PCI/MSI allocation goes through the native
path which runs out of vectors and causes malfunction.

Invoke it after x86_init.pci.arch_init().

Fixes: 6b15ffa0

 ("x86/irq: Initialize PCI/MSI domain at PCI init time")
Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87pn18djte.fsf@nanos.tec.linutronix.de


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit ade9679c ]

Fix a build error for undefined 'TI_PRE_COUNT' by adding it to
asm-offsets.c.

  h8300-linux-ld: arch/h8300/kernel/entry.o: in function `resume_kernel': (.text+0x29a): undefined reference to `TI_PRE_COUNT'

Link: https://lkml.kernel.org/r/20210212021650.22740-1-rdunlap@infradead.org
Fixes: df2078b8

 ("h8300: Low level entry")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 256b92af ]

Commit

  20bf2b37 ("x86/build: Disable CET instrumentation in the kernel")

disabled CET instrumentation which gets added by default by the Ubuntu
gcc9 and 10 by default, but did that only for 64-bit builds. It would
still fail when building a 32-bit target. So disable CET for all x86
builds.

Fixes: 20bf2b37

 ("x86/build: Disable CET instrumentation in the kernel")
Reported-by: AC <achirvasub@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: AC <achirvasub@gmail.com>
Link: https://lkml.kernel.org/r/YCCIgMHkzh/xT4ex@arch-chirva.localdomain


Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit c1c35cf7 ]

If not in long mode, the low bits of CR3 are reserved but not enforced to
be zero, so remove those checks.  If in long mode, however, the MBZ bits
extend down to the highest physical address bit of the guest, excluding
the encryption bit.

Make the checks consistent with the above, and match them between
nested_vmcb_checks and KVM_SET_SREGS.

Cc: stable@vger.kernel.org
Fixes: 761e4169 ("KVM: nSVM: Check that MBZ bits in CR3 and CR4 are not set on vmrun of nested guests")
Fixes: a780a3ea

 ("KVM: X86: Fix reserved bits check for MOV to CR3")
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 816ef8d7 ]

With CONFIG_X86_5LEVEL, CONFIG_UBSAN and CONFIG_UBSAN_UNSIGNED_OVERFLOW
enabled, clang fails the build with

  x86_64-linux-ld: arch/x86/platform/efi/efi_64.o: in function `efi_sync_low_kernel_mappings':
  efi_64.c:(.text+0x22c): undefined reference to `__compiletime_assert_354'

which happens due to -fsanitize=unsigned-integer-overflow being enabled:

  -fsanitize=unsigned-integer-overflow: Unsigned integer overflow, where
  the result of an unsigned integer computation cannot be represented
  in its type. Unlike signed integer overflow, this is not undefined
  behavior, but it is often unintentional. This sanitizer does not check
  for lossy implicit conversions performed before such a computation
  (see -fsanitize=implicit-conversion).

and that fires when the (intentional) EFI_VA_START/END defines overflow
an unsigned long, leading to the assertion expressions not getting
optimized away (on GCC they do)...

However, those checks are superfluous: the runtime services mapping
code already makes sure the ranges don't overshoot EFI_VA_END as the
EFI mapping range is hardcoded. On each runtime services call, it is
switched to the EFI-specific PGD and even if mappings manage to escape
that last PGD, this won't remain unnoticed for long.

So rip them out.

See https://github.com/ClangBuiltLinux/linux/issues/256

 for more info.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: http://lkml.kernel.org/r/20210107223424.4135538-1-arnd@kernel.org


Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 4d62e81b

 ]

Giancarlo Ferrari reports the following oops while trying to use kexec:

 Unable to handle kernel paging request at virtual address 80112f38
 pgd = fd7ef03e
 [80112f38] *pgd=0001141e(bad)
 Internal error: Oops: 80d [#1] PREEMPT SMP ARM
 ...

This is caused by machine_kexec() trying to set the kernel text to be
read/write, so it can poke values into the relocation code before
copying it - and an interrupt occuring which changes the page tables.
The subsequent writes then hit read-only sections that trigger a
data abort resulting in the above oops.

Fix this by copying the relocation code, and then writing the variables
into the destination, thereby avoiding the need to make the kernel text
read/write.

Reported-by: Giancarlo Ferrari <giancarlo.ferrari89@gmail.com>
Tested-by: Giancarlo Ferrari <giancarlo.ferrari89@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 9c698bff

 ]

Ensure that the signal page contains our poison instruction to increase
the protection against ROP attacks and also contains well defined
contents.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 5638159f ]

This reverts commit c17e9377

.

The lpc32xx clock driver is not able to actually change the PLL rate as
this would require reparenting ARM_CLK, DDRAM_CLK, PERIPH_CLK to SYSCLK,
then stop the PLL, update the register, restart the PLL and wait for the
PLL to lock and finally reparent ARM_CLK, DDRAM_CLK, PERIPH_CLK to HCLK
PLL.

Currently, the HCLK driver simply updates the registers but this has no
real effect and all the clock rate calculation end up being wrong. This is
especially annoying for the peripheral (e.g. UARTs, I2C, SPI).

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20210203090320.GA3760268@piout.net

'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 2ab54382

 ]

virt_addr_valid macro checks that a virtual address is valid, ie that
the address belongs to the linear mapping and that the corresponding
 physical page exists.

Add the missing check that ensures the virtual address belongs to the
linear mapping, otherwise __virt_to_phys, when compiled with
CONFIG_DEBUG_VIRTUAL enabled, raises a WARN that is interpreted as a
kernel bug by syzbot.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 8acf4178

 ]

Add Alder Lake mobile processor to CPU list to enumerate and enable the
split lock feature.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20210201190007.4031869-1-fenghua.yu@intel.com


Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 74532de4

 ]

NanoPi R2S is headless, so rightly does not enable any of the display
interface hardware, which currently provokes an obnoxious error in the
boot log from the fake DRM device failing to find anything to bind to.
It probably isn't *too* hard to obviate the fake device shenanigans
entirely with a bit of driver reshuffling, but for now let's just
disable it here to shut up the spurious error.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/c4553dfad1ad6792c4f22454c135ff55de77e2d6.1611186099.git.robin.murphy@arm.com


Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 94a5400f

 ]

A test with the command below gives this error:
/arch/arm64/boot/dts/rockchip/rk3399-evb.dt.yaml: video-codec@ff660000:
'interrupt-names' does not match any of the regexes: 'pinctrl-[0-9]+'

The rkvdec driver gets it irq with help of the platform_get_irq()
function, so remove the interrupt-names property from the rk3399
vdec node.

make ARCH=arm64 dtbs_check
DT_SCHEMA_FILES=Documentation/devicetree/bindings/
media/rockchip,vdec.yaml

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Link: https://lore.kernel.org/r/20210117181653.24886-1-jbx6244@gmail.com


Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 06862d78 ]

We get suspcious RCU usage splats with cpuidle in several places in
omap_enter_idle_coupled() with the kernel debug options enabled:

RCU used illegally from extended quiescent state!
...
(_raw_spin_lock_irqsave)
(omap_enter_idle_coupled+0x17c/0x2d8)
(omap_enter_idle_coupled)
(cpuidle_enter_state)
(cpuidle_enter_state_coupled)
(cpuidle_enter)

Let's use RCU_NONIDLE to suppress these splats. Things got changed around
with commit 1098582a ("sched,idle,rcu: Push rcu_idle deeper into the
idle path") that started triggering these warnings.

For the tick_broadcast related calls, ideally we'd just switch over to
using CPUIDLE_FLAG_TIMER_STOP for omap_enter_idle_coupled() to have the
generic cpuidle code handle the tick_broadcast related calls for us and
then just drop the tick_broadcast calls here.

But we're currently missing the call in the common cpuidle code for
tick_broadcast_enable() that CPU1 hotplug needs as described in earlier
commit 50d6b3cf

 ("ARM: OMAP2+: fix lack of timer interrupts on CPU1
after hotplug").

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 93f2a115

 ]

The GCC_LPASS_Q6_AXI_CLK and GCC_LPASS_SWAY_CLK clocks may not be
touched on a typical UEFI based SDM845 device, but when the kernel is
built with CONFIG_SDM_LPASSCC_845 this happens, unless they are marked
as protected-clocks in the DT.

This was done for the MTP and the Pocophone, but not for DB845c and the
Lenovo Yoga C630 - causing these to fail to boot if the LPASS clock
controller is enabled (which it typically isn't).

Tested-by: Vinod Koul <vkoul@kernel.org> #on db845c
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20201222001103.3112306-1-bjorn.andersson@linaro.org


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 43f20b1c

 ]

It recently became apparent that the lack of a 'device_type = "pci"'
in the PCIe root complex node for rk3399 is a violation of the PCI
binding, as documented in IEEE Std 1275-1994. Changes to the kernel's
parsing of the DT made such violation fatal, as drivers cannot
probe the controller anymore.

Add the missing property makes the PCIe node compliant. While we
are at it, drop the pointless linux,pci-domain property, which only
makes sense when there are multiple host bridges.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200815125112.462652-3-maz@kernel.org


Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

commit c4295ab0 upstream.

After Commit 3499ba81 ("xen: Fix event channel callback via
INTX/GSI"), xenbus_probe() will be called too early on Arm. This will
recent to a guest hang during boot.

If the hang wasn't there, we would have ended up to call
xenbus_probe() twice (the second time is in xenbus_probe_initcall()).

We don't need to initialize xenbus_probe() early for Arm guest.
Therefore, the call in xen_guest_init() is now removed.

After this change, there is no more external caller for xenbus_probe().
So the function is turned to a static one. Interestingly there were two
prototypes for it.

Cc: stable@vger.kernel.org
Fixes: 3499ba81

 ("xen: Fix event channel callback via INTX/GSI")
Reported-by: Ian Jackson <iwj@xenproject.org>
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/20210210170654.5377-1-julien@xen.org


Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 3da3cc1b upstream.

VSC8541 phys need a special reset sequence, which the driver doesn't
currentlny support.  As a result enabling the reset via GPIO essentially
guarnteees that the device won't work correctly.  We've been relying on
bootloaders to reset the device for years, with this revert we'll go
back to doing so until we can sort out how to get the reset sequence
into the kernel.

This reverts commit a0fa9d72.

Fixes: a0fa9d72

 ("dts: phy: add GPIO number and active state used for phy reset")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

See: https://github.com/raspberrypi/linux/issues/4144

(from https://github.com/RPi-Distro/repo/issues/229

)

Signed-off-by: Phil Elwell <phil@raspberrypi.com>

If the shutdown process is delayed enough to trigger the shutdown
timeout then one or more states in the shutdown sequence might be
skipped. Ensure that all LEDs are turned off regardless by explicitly
doing so in the shutdown state, as an example of good practices.

Signed-off-by: Phil Elwell <phil@raspberrypi.com>

Includes optional use of GPIOs 0&1 / BSC0 for DDC to read the EDID
from the display.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

VGA666 uses "vga-connector" from DRM_DISPLAY_CONNECTOR, and
"dumb-vga-dac" from DRM_SIMPLE_BRIDGE to connect up, so add them
to the defconfigs.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

VGA666 doesn't use the DE or PCLK signals, therefore there is
no point in claiming their use. It's also then possible to
use GPIOs 0&1 for DDC to read the EDID from the display.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

The gpio-fsm property "num-soft-gpios" triggers a kernel DT checker
that warns about the lack of #gpio-cells on a random node with the
phandle that just happens to match the number of soft GPIOs. Rename
the property to "num-swgpios" to avoid the warning.

Signed-off-by: Phil Elwell <phil@raspberrypi.com>

commit 24321ac6 upstream.

Commit 0138ba57 ("powerpc/64/signal: Balance return predictor
stack in signal trampoline") changed __kernel_sigtramp_rt64() VDSO and
trampoline code, and introduced a regression in the way glibc's
backtrace()[1] detects the signal-handler stack frame. Apart from the
practical implications, __kernel_sigtramp_rt64() was a VDSO function
with the semantics that it is a function you can call from userspace
to end a signal handling. Now this semantics are no longer valid.

I believe the aforementioned change affects all releases since 5.9.

This patch tries to fix both the semantics and practical aspect of
__kernel_sigtramp_rt64() returning it to the previous code, whilst
keeping the intended behaviour of 0138ba57 by adding a new symbol
to serve as the jump target from the kernel to the trampoline. Now the
trampoline has two parts, a new entry point and the old return point.

[1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2021-January/223194.html

Fixes: 0138ba57

 ("powerpc/64/signal: Balance return predictor stack in signal trampoline")
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Raoni Fassina Firmino <raoni@linux.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Minor tweaks to change log formatting, add stable tag]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210201200505.iz46ubcizipnkcxe@work-tp


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 93a3b097

.

GIC interrupt 117 is shared with the HDMI interrupt controller
and all the standard BSC I2C controllers. Whilst the BSC driver
flags the interrupt as shared, there doesn't appear to be an
easy way to flag the controller as being on a shared parent
interrupt.

Revert to polling the I2C controllers.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

This reverts commit c765fd45

.

bsc_intr is being removed again as it causes issues.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

commit 25a068b8

 upstream.

Jan Kiszka reported that the x2apic_wrmsr_fence() function uses a plain
MFENCE while the Intel SDM (10.12.3 MSR Access in x2APIC Mode) calls for
MFENCE; LFENCE.

Short summary: we have special MSRs that have weaker ordering than all
the rest. Add fencing consistent with current SDM recommendations.

This is not known to cause any issues in practice, only in theory.

Longer story below:

The reason the kernel uses a different semantic is that the SDM changed
(roughly in late 2017). The SDM changed because folks at Intel were
auditing all of the recommended fences in the SDM and realized that the
x2apic fences were insufficient.

Why was the pain MFENCE judged insufficient?

WRMSR itself is normally a serializing instruction. No fences are needed
because the instruction itself serializes everything.

But, there are explicit exceptions for this serializing behavior written
into the WRMSR instruction documentation for two classes of MSRs:
IA32_TSC_DEADLINE and the X2APIC MSRs.

Back to x2apic: WRMSR is *not* serializing in this specific case.
But why is MFENCE insufficient? MFENCE makes writes visible, but
only affects load/store instructions. WRMSR is unfortunately not a
load/store instruction and is unaffected by MFENCE. This means that a
non-serializing WRMSR could be reordered by the CPU to execute before
the writes made visible by the MFENCE have even occurred in the first
place.

This means that an x2apic IPI could theoretically be triggered before
there is any (visible) data to process.

Does this affect anything in practice? I honestly don't know. It seems
quite possible that by the time an interrupt gets to consume the (not
yet) MFENCE'd data, it has become visible, mostly by accident.

To be safe, add the SDM-recommended fences for all x2apic WRMSRs.

This also leaves open the question of the _other_ weakly-ordered WRMSR:
MSR_IA32_TSC_DEADLINE. While it has the same ordering architecture as
the x2APIC MSRs, it seems substantially less likely to be a problem in
practice. While writes to the in-memory Local Vector Table (LVT) might
theoretically be reordered with respect to a weakly-ordered WRMSR like
TSC_DEADLINE, the SDM has this to say:

  In x2APIC mode, the WRMSR instruction is used to write to the LVT
  entry. The processor ensures the ordering of this write and any
  subsequent WRMSR to the deadline; no fencing is required.

But, that might still leave xAPIC exposed. The safest thing to do for
now is to add the extra, recommended LFENCE.

 [ bp: Massage commit message, fix typos, drop accidentally added
   newline to tools/arch/x86/include/asm/barrier.h. ]

Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200305174708.F77040DD@viggo.jf.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 3943abf2 upstream.

local_db_save() is called at the start of exc_debug_kernel(), reads DR7 and
disables breakpoints to prevent recursion.

When running in a guest (X86_FEATURE_HYPERVISOR), local_db_save() reads the
per-cpu variable cpu_dr7 to check whether a breakpoint is active or not
before it accesses DR7.

A data breakpoint on cpu_dr7 therefore results in infinite #DB recursion.

Disallow data breakpoints on cpu_dr7 to prevent that.

Fixes: 84b6a349

("x86/entry: Optimize local_db_save() for virt")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210204152708.21308-2-jiangshanlai@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit c4bed4b9 upstream.

When FSGSBASE is enabled, paranoid_entry() fetches the per-CPU GSBASE value
via __per_cpu_offset or pcpu_unit_offsets.

When a data breakpoint is set on __per_cpu_offset[cpu] (read-write
operation), the specific CPU will be stuck in an infinite #DB loop.

RCU will try to send an NMI to the specific CPU, but it is not working
either since NMI also relies on paranoid_entry(). Which means it's
undebuggable.

Fixes: eaad9812

("x86/entry/64: Introduce the FIND_PERCPU_BASE macro")
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210204152708.21308-1-jiangshanlai@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 9ad22e16 upstream.

Tom reported that one of the GDB test-cases failed, and Boris bisected
it to commit:

  d53d9bc0 ("x86/debug: Change thread.debugreg6 to thread.virtual_dr6")

The debugging session led us to commit:

  6c0aca28 ("x86: Ignore trap bits on single step exceptions")

It turns out that TF and data breakpoints are both traps and will be
merged, while instruction breakpoints are faults and will not be merged.
This means 6c0aca28 is wrong, only TF and instruction breakpoints
need to be excluded while TF and data breakpoints can be merged.

 [ bp: Massage commit message. ]

Fixes: d53d9bc0 ("x86/debug: Change thread.debugreg6 to thread.virtual_dr6")
Fixes: 6c0aca28

 ("x86: Ignore trap bits on single step exceptions")
Reported-by: Tom de Vries <tdevries@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/YBMAbQGACujjfz%2Bi@hirez.programming.kicks-ass.net
Link: https://lkml.kernel.org/r/20210128211627.GB4348@worktop.programming.kicks-ass.net


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 20bf2b37 upstream.

With retpolines disabled, some configurations of GCC, and specifically
the GCC versions 9 and 10 in Ubuntu will add Intel CET instrumentation
to the kernel by default. That breaks certain tracing scenarios by
adding a superfluous ENDBR64 instruction before the fentry call, for
functions which can be called indirectly.

CET instrumentation isn't currently necessary in the kernel, as CET is
only supported in user space. Disable it unconditionally and move it
into the x86's Makefile as CET/CFI... enablement should be a per-arch
decision anyway.

 [ bp: Massage and extend commit message. ]

Fixes: 29be86d7

 ("kbuild: add -fcf-protection=none when using retpoline flags")
Reported-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Cc: <stable@vger.kernel.org>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: https://lkml.kernel.org/r/20210128215219.6kct3h2eiustncws@treble


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 538eea53 upstream.

The tegra_uart_config of the DEBUG_LL code is now placed right at the
start of the .text section after commit which enabled debug output in the
decompressor. Tegra devices are not booting anymore if DEBUG_LL is enabled
since tegra_uart_config data is executes as a code. Fix the misplaced
tegra_uart_config storage by embedding it into the code.

Cc: stable@vger.kernel.org
Fixes: 2596a72d

 ("ARM: 9009/1: uncompress: Enable debug in head.S")
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 39d3454c

 upstream.

Building with gcc 4.9.2 reveals a latent bug in the PCI accessors
for Footbridge platforms, which causes a fatal alignment fault
while accessing IO memory. Fix this by making the assembly volatile.

Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 18173982 upstream.

With the arrival of

commit 2fee9583 ("spi: dt-bindings: clarify CS behavior for spi-cs-high and gpio descriptors")

it was clarified what the proper state for cs-gpios should be, even if the
flag is ignored. The driver code is doing the right thing since

766c6b63 ("spi: fix client driver breakages when using GPIO descriptors")

The chip-select of the td028ttec1 panel is active-low, so we must omit spi-cs-high;
attribute (already removed by separate patch) and should now use GPIO_ACTIVE_LOW for
the client device description to be fully consistent.

Fixes: 766c6b63

 ("spi: fix client driver breakages when using GPIO descriptors")
CC: stable@vger.kernel.org
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 07af7810 upstream.

This reverts

commit f1f028ff ("DTS: ARM: gta04: introduce legacy spi-cs-high to make display work again")

which had to be intruduced after

commit 6953c57a ("gpio: of: Handle SPI chipselect legacy bindings")

broke the GTA04 display. This contradicted the data sheet but was the only
way to get it as an spi client operational again.

The panel data sheet defines the chip-select to be active low.

Now, with the arrival of

commit 766c6b63 ("spi: fix client driver breakages when using GPIO descriptors")

the logic of interaction between spi-cs-high and the gpio descriptor flags
has been changed a second time, making the display broken again. So we have
to remove the original fix which in retrospect was a workaround of a bug in
the spi subsystem and not a feature of the panel or bug in the device tree.

With this fix the device tree is back in sync with the data sheet and
spi subsystem code.

Fixes: 766c6b63

 ("spi: fix client driver breakages when using GPIO descriptors")
CC: stable@vger.kernel.org
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 031b91a5 upstream.

Set cr3_lm_rsvd_bits, which is effectively an invalid GPA mask, at vCPU
reset.  The reserved bits check needs to be done even if userspace never
configures the guest's CPUID model.

Cc: stable@vger.kernel.org
Fixes: 0107973a

 ("KVM: x86: Introduce cr3_lm_rsvd_bits in kvm_vcpu_arch")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210204000117.3303214-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 943dea8a upstream.

Set the emulator context to PROT64 if SYSENTER transitions from 32-bit
userspace (compat mode) to a 64-bit kernel, otherwise the RIP update at
the end of x86_emulate_insn() will incorrectly truncate the new RIP.

Note, this bug is mostly limited to running an Intel virtual CPU model on
an AMD physical CPU, as other combinations of virtual and physical CPUs
do not trigger full emulation.  On Intel CPUs, SYSENTER in compatibility
mode is legal, and unconditionally transitions to 64-bit mode.  On AMD
CPUs, SYSENTER is illegal in compatibility mode and #UDs.  If the vCPU is
AMD, KVM injects a #UD on SYSENTER in compat mode.  If the pCPU is Intel,
SYSENTER will execute natively and not trigger #UD->VM-Exit (ignoring
guest TLB shenanigans).

Fixes: fede8076

 ("KVM: x86: handle wrap around 32-bit address space")
Cc: stable@vger.kernel.org
Signed-off-by: Jonny Barker <jonny@jonnybarker.com>
[sean: wrote changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210202165546.2390296-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>