linux.git/arch, branch v5.4.63

arm64: tegra: Add missing timeout clock to Tegra210 SDMMC

2020-09-05T09:22:51+00:00

commit 679f71fa0db2d777f39c7a5af7f7c0689fc713fa upstream.

commit 742af7e7a0a1 ("arm64: tegra: Add Tegra210 support")

Tegra210 uses separate SDMMC_LEGACY_TM clock for data timeout and
this clock is not enabled currently which is not recommended.

Tegra SDMMC advertises 12Mhz as timeout clock frequency in host
capability register.

So, this clock should be kept enabled by SDMMC driver.

Fixes: 742af7e7a0a1 ("arm64: tegra: Add Tegra210 support")
Cc: stable  # 5.4
Tested-by: Jon Hunter 
Reviewed-by: Jon Hunter 
Signed-off-by: Sowjanya Komatineni 
Link: https://lore.kernel.org/r/1598548861-32373-5-git-send-email-skomatineni@nvidia.com
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

arm64: tegra: Add missing timeout clock to Tegra186 SDMMC nodes

2020-09-05T09:22:50+00:00

commit baba217d2c4446b6eef309d81d8776cb5c68cb55 upstream.

commit 39cb62cb8973 ("arm64: tegra: Add Tegra186 support")

Tegra186 uses separate SDMMC_LEGACY_TM clock for data timeout and
this clock is not enabled currently which is not recommended.

Tegra186 SDMMC advertises 12Mhz as timeout clock frequency in host
capability register and uses it by default.

So, this clock should be kept enabled by the SDMMC driver.

Fixes: 39cb62cb8973 ("arm64: tegra: Add Tegra186 support")
Cc: stable  # 5.4
Tested-by: Jon Hunter 
Reviewed-by: Jon Hunter 
Signed-off-by: Sowjanya Komatineni 
Link: https://lore.kernel.org/r/1598548861-32373-6-git-send-email-skomatineni@nvidia.com
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

arm64: tegra: Add missing timeout clock to Tegra194 SDMMC nodes

2020-09-05T09:22:50+00:00

commit c956c0cd4f6f4aac4f095621b1c4e1c5ee1df877 upstream.

commit 5425fb15d8ee ("arm64: tegra: Add Tegra194 chip device tree")

Tegra194 uses separate SDMMC_LEGACY_TM clock for data timeout and
this clock is not enabled currently which is not recommended.

Tegra194 SDMMC advertises 12Mhz as timeout clock frequency in host
capability register.

So, this clock should be kept enabled by SDMMC driver.

Fixes: 5425fb15d8ee ("arm64: tegra: Add Tegra194 chip device tree")
Cc: stable  # 5.4
Tested-by: Jon Hunter 
Reviewed-by: Jon Hunter 
Signed-off-by: Sowjanya Komatineni 
Link: https://lore.kernel.org/r/1598548861-32373-7-git-send-email-skomatineni@nvidia.com
Signed-off-by: Ulf Hansson 
Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Set HCR_EL2.PTW to prevent AT taking synchronous exception

2020-09-05T09:22:50+00:00

commit 71a7f8cb1ca4ca7214a700b1243626759b6c11d4 upstream.

AT instructions do a translation table walk and return the result, or
the fault in PAR_EL1. KVM uses these to find the IPA when the value is
not provided by the CPU in HPFAR_EL1.

If a translation table walk causes an external abort it is taken as an
exception, even if it was due to an AT instruction. (DDI0487F.a's D5.2.11
"Synchronous faults generated by address translation instructions")

While we previously made KVM resilient to exceptions taken due to AT
instructions, the device access causes mismatched attributes, and may
occur speculatively. Prevent this, by forbidding a walk through memory
described as device at stage2. Now such AT instructions will report a
stage2 fault.

Such a fault will cause KVM to restart the guest. If the AT instructions
always walk the page tables, but guest execution uses the translation cached
in the TLB, the guest can't make forward progress until the TLB entry is
evicted. This isn't a problem, as since commit 5dcd0fdbb492 ("KVM: arm64:
Defer guest entry when an asynchronous exception is pending"), KVM will
return to the host to process IRQs allowing the rest of the system to keep
running.

Cc: stable@vger.kernel.org # 
Reviewed-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Andre Przywara 
Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Survive synchronous exceptions caused by AT instructions

2020-09-05T09:22:50+00:00

commit 88a84ccccb3966bcc3f309cdb76092a9892c0260 upstream.

KVM doesn't expect any synchronous exceptions when executing, any such
exception leads to a panic(). AT instructions access the guest page
tables, and can cause a synchronous external abort to be taken.

The arm-arm is unclear on what should happen if the guest has configured
the hardware update of the access-flag, and a memory type in TCR_EL1 that
does not support atomic operations. B2.2.6 "Possible implementation
restrictions on using atomic instructions" from DDI0487F.a lists
synchronous external abort as a possible behaviour of atomic instructions
that target memory that isn't writeback cacheable, but the page table
walker may behave differently.

Make KVM robust to synchronous exceptions caused by AT instructions.
Add a get_user() style helper for AT instructions that returns -EFAULT
if an exception was generated.

While KVM's version of the exception table mixes synchronous and
asynchronous exceptions, only one of these can occur at each location.

Re-enter the guest when the AT instructions take an exception on the
assumption the guest will take the same exception. This isn't guaranteed
to make forward progress, as the AT instructions may always walk the page
tables, but guest execution may use the translation cached in the TLB.

This isn't a problem, as since commit 5dcd0fdbb492 ("KVM: arm64: Defer guest
entry when an asynchronous exception is pending"), KVM will return to the
host to process IRQs allowing the rest of the system to keep running.

Cc: stable@vger.kernel.org # 
Reviewed-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Andre Przywara 
Signed-off-by: Greg Kroah-Hartman

KVM: arm64: Add kvm_extable for vaxorcism code

2020-09-05T09:22:50+00:00

commit e9ee186bb735bfc17fa81dbc9aebf268aee5b41e upstream.

KVM has a one instruction window where it will allow an SError exception
to be consumed by the hypervisor without treating it as a hypervisor bug.
This is used to consume asynchronous external abort that were caused by
the guest.

As we are about to add another location that survives unexpected exceptions,
generalise this code to make it behave like the host's extable.

KVM's version has to be mapped to EL2 to be accessible on nVHE systems.

The SError vaxorcism code is a one instruction window, so has two entries
in the extable. Because the KVM code is copied for VHE and nVHE, we end up
with four entries, half of which correspond with code that isn't mapped.

Cc:  # 5.4.x
Signed-off-by: James Morse 
Reviewed-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Andre Przywara 
Signed-off-by: Greg Kroah-Hartman

kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables

2020-09-03T09:27:10+00:00

commit e4a42c82e943b97ce124539fcd7a47445b43fa0d upstream.

Redefine GZIP, BZIP2, LZOP variables as KGZIP, KBZIP2, KLZOP resp.
GZIP, BZIP2, LZOP env variables are reserved by the tools. The original
attempt to redefine them internally doesn't work in makefiles/scripts
intercall scenarios, e.g., "make GZIP=gzip bindeb-pkg" and results in
broken builds. There can be other broken build commands because of this,
so the universal solution is to use non-reserved env variables for the
compression tools.

Fixes: 8dfb61dcbace ("kbuild: add variables for compression tools")
Signed-off-by: Denis Efremov 
Tested-by: Guenter Roeck 
Signed-off-by: Masahiro Yamada 
Cc: Matthias Maennich 
Signed-off-by: Greg Kroah-Hartman

kbuild: add variables for compression tools

2020-09-03T09:27:10+00:00

commit 8dfb61dcbaceb19a5ded5e9c9dcf8d05acc32294 upstream.

Allow user to use alternative implementations of compression tools,
such as pigz, pbzip2, pxz. For example, multi-threaded tools to
speed up the build:
$ make GZIP=pigz BZIP2=pbzip2

Variables _GZIP, _BZIP2, _LZOP are used internally because original env
vars are reserved by the tools. The use of GZIP in gzip tool is obsolete
since 2015. However, alternative implementations (e.g., pigz) still rely
on it. BZIP2, BZIP, LZOP vars are not obsolescent.

The credit goes to @grsecurity.

As a sidenote, for multi-threaded lzma, xz compression one can use:
$ export XZ_OPT="--threads=0"

Signed-off-by: Denis Efremov 
Signed-off-by: Masahiro Yamada 
Signed-off-by: Matthias Maennich 
Signed-off-by: Greg Kroah-Hartman

x86/hotplug: Silence APIC only after all interrupts are migrated

2020-09-03T09:27:06+00:00

commit 52d6b926aabc47643cd910c85edb262b7f44c168 upstream.

There is a race when taking a CPU offline. Current code looks like this:

native_cpu_disable()
{
	...
	apic_soft_disable();
	/*
	 * Any existing set bits for pending interrupt to
	 * this CPU are preserved and will be sent via IPI
	 * to another CPU by fixup_irqs().
	 */
	cpu_disable_common();
	{
		....
		/*
		 * Race window happens here. Once local APIC has been
		 * disabled any new interrupts from the device to
		 * the old CPU are lost
		 */
		fixup_irqs(); // Too late to capture anything in IRR.
		...
	}
}

The fix is to disable the APIC *after* cpu_disable_common().

Testing was done with a USB NIC that provided a source of frequent
interrupts. A script migrated interrupts to a specific CPU and
then took that CPU offline.

Fixes: 60dcaad5736f ("x86/hotplug: Silence APIC and NMI when CPU is dead")
Reported-by: Evan Green 
Signed-off-by: Ashok Raj 
Signed-off-by: Thomas Gleixner 
Tested-by: Mathias Nyman 
Tested-by: Evan Green 
Reviewed-by: Evan Green 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/875zdarr4h.fsf@nanos.tec.linutronix.de/
Link: https://lore.kernel.org/r/1598501530-45821-1-git-send-email-ashok.raj@intel.com
Signed-off-by: Greg Kroah-Hartman

powerpc/perf: Fix crashes with generic_compat_pmu & BHRB

2020-09-03T09:27:05+00:00

commit b460b512417ae9c8b51a3bdcc09020cd6c60ff69 upstream.

The bhrb_filter_map ("The Branch History Rolling Buffer") callback is
only defined in raw CPUs' power_pmu structs. The "architected" CPUs
use generic_compat_pmu, which does not have this callback, and crashes
occur if a user tries to enable branch stack for an event.

This add a NULL pointer check for bhrb_filter_map() which behaves as
if the callback returned an error.

This does not add the same check for config_bhrb() as the only caller
checks for cpuhw->bhrb_users which remains zero if bhrb_filter_map==0.

Fixes: be80e758d0c2 ("powerpc/perf: Add generic compat mode pmu driver")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Alexey Kardashevskiy 
Reviewed-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200602025612.62707-1-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman