Oliver Upton [Thu, 7 Mar 2024 00:55:53 +0000 (00:55 +0000)]
Merge branch kvm-arm64/lpi-xarray into kvmarm/next
* kvm-arm64/lpi-xarray:
: xarray-based representation of vgic LPIs
:
: KVM's linked-list of LPI state has proven to be a bottleneck in LPI
: injection paths, due to lock serialization when acquiring / releasing a
: reference on an IRQ.
:
: Start the tedious process of reworking KVM's LPI injection by replacing
: the LPI linked-list with an xarray, leveraging this to allow RCU readers
: to walk it outside of the spinlock.
KVM: arm64: vgic: Don't acquire the lpi_list_lock in vgic_put_irq()
KVM: arm64: vgic: Ensure the irq refcount is nonzero when taking a ref
KVM: arm64: vgic: Rely on RCU protection in vgic_get_lpi()
KVM: arm64: vgic: Free LPI vgic_irq structs in an RCU-safe manner
KVM: arm64: vgic: Use atomics to count LPIs
KVM: arm64: vgic: Get rid of the LPI linked-list
KVM: arm64: vgic-its: Walk the LPI xarray in vgic_copy_lpi_list()
KVM: arm64: vgic-v3: Iterate the xarray to find pending LPIs
KVM: arm64: vgic: Use xarray to find LPI in vgic_get_lpi()
KVM: arm64: vgic: Store LPIs in an xarray
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Thu, 7 Mar 2024 00:50:48 +0000 (00:50 +0000)]
Merge branch kvm-arm64/vm-configuration into kvmarm/next
* kvm-arm64/vm-configuration: (29 commits)
: VM configuration enforcement, courtesy of Marc Zyngier
:
: Userspace has gained the ability to control the features visible
: through the ID registers, yet KVM didn't take this into account as the
: effective feature set when determing trap / emulation behavior. This
: series adds:
:
: - Mechanism for testing the presence of a particular CPU feature in the
: guest's ID registers
:
: - Infrastructure for computing the effective value of VNCR-backed
: registers, taking into account the RES0 / RES1 bits for a particular
: VM configuration
:
: - Implementation of 'fine-grained UNDEF' controls that shadow the FGT
: register definitions.
KVM: arm64: Don't initialize idreg debugfs w/ preemption disabled
KVM: arm64: Fail the idreg iterator if idregs aren't initialized
KVM: arm64: Make build-time check of RES0/RES1 bits optional
KVM: arm64: Add debugfs file for guest's ID registers
KVM: arm64: Snapshot all non-zero RES0/RES1 sysreg fields for later checking
KVM: arm64: Make FEAT_MOPS UNDEF if not advertised to the guest
KVM: arm64: Make AMU sysreg UNDEF if FEAT_AMU is not advertised to the guest
KVM: arm64: Make PIR{,E0}_EL1 UNDEF if S1PIE is not advertised to the guest
KVM: arm64: Make TLBI OS/Range UNDEF if not advertised to the guest
KVM: arm64: Streamline save/restore of HFG[RW]TR_EL2
KVM: arm64: Move existing feature disabling over to FGU infrastructure
KVM: arm64: Propagate and handle Fine-Grained UNDEF bits
KVM: arm64: Add Fine-Grained UNDEF tracking information
KVM: arm64: Rename __check_nv_sr_forward() to triage_sysreg_trap()
KVM: arm64: Use the xarray as the primary sysreg/sysinsn walker
KVM: arm64: Register AArch64 system register entries with the sysreg xarray
KVM: arm64: Always populate the trap configuration xarray
KVM: arm64: nv: Move system instructions to their own sys_reg_desc array
KVM: arm64: Drop the requirement for XARRAY_MULTI
KVM: arm64: nv: Turn encoding ranges into discrete XArray stores
...
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Thu, 7 Mar 2024 00:45:24 +0000 (00:45 +0000)]
Merge branch kvm-arm64/feat_e2h0 into kvmarm/next
* kvm-arm64/feat_e2h0:
: Support for FEAT_E2H0, courtesy of Marc Zyngier
:
: As described in the cover letter:
:
: Since ARMv8.1, the architecture has grown the VHE feature, which makes
: EL2 a superset of EL1. With ARMv9.5 (and retroactively allowed from
: ARMv8.1), the architecture allows implementations to have VHE as the
: *only* implemented behaviour, meaning that HCR_EL2.E2H can be
: implemented as RES1. As a follow-up, HCR_EL2.NV1 can also be
: implemented as RES0, making the VHE-ness of the architecture
: recursive.
:
: This series adds support for detecting the architectural feature of E2H
: being RES1, leveraging the existing infrastructure for handling
: out-of-spec CPUs that are VHE-only. Additionally, the (incomplete) NV
: infrastructure in KVM is updated to enforce E2H=1 for guest hypervisors
: on implementations that do not support NV1.
arm64: cpufeatures: Fix FEAT_NV check when checking for FEAT_NV1
arm64: cpufeatures: Only check for NV1 if NV is present
arm64: cpufeatures: Add missing ID_AA64MMFR4_EL1 to __read_sysreg_by_encoding()
KVM: arm64: Handle Apple M2 as not having HCR_EL2.NV1 implemented
KVM: arm64: Force guest's HCR_EL2.E2H RES1 when NV1 is not implemented
KVM: arm64: Expose ID_AA64MMFR4_EL1 to guests
arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is negative
arm64: cpufeature: Detect HCR_EL2.NV1 being RES0
arm64: cpufeature: Add ID_AA64MMFR4_EL1 handling
arm64: sysreg: Add layout for ID_AA64MMFR4_EL1
arm64: cpufeature: Correctly display signed override values
arm64: cpufeatures: Correctly handle signed values
arm64: Add macro to compose a sysreg field value
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Thu, 29 Feb 2024 14:54:17 +0000 (14:54 +0000)]
KVM: arm64: Fix TRFCR_EL1/PMSCR_EL1 access in hVHE mode
When running in hVHE mode, EL1 accesses are performed with the EL12
accessor, as we run with HCR_EL2.E2H=1.
Unfortunately, both PMSCR_EL1 and TRFCR_EL1 are used with the
EL1 accessor, meaning that we actually affect the EL2 state. Duh.
Switch to using the {read,write}_sysreg_el1() helpers that will do
the right thing in all circumstances.
Note that the 'Fixes:' tag doesn't represent the point where the bug
was introduced (there is no such point), but the first practical point
where the hVHE feature is usable.
Cc: James Clark <james.clark@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Fixes: 38cba55008e5 ("KVM: arm64: Force HCR_E2H in guest context when ARM64_KVM_HVHE is set") Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240229145417.3606279-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
KVM: selftests: aarch64: Remove unused functions from vpmu test
vpmu_counter_access's disable_counter() carries a bug that disables
all the counters that are enabled, instead of just the requested one.
Fortunately, it's not an issue as there are no callers of it. Hence,
instead of fixing it, remove the definition entirely.
Testing KVM with DEBUG_ATOMIC_SLEEP enabled doesn't get far before hitting the
first splat:
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1578
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 13062, name: vgic_lpi_stress
preempt_count: 1, expected: 0
2 locks held by vgic_lpi_stress/13062:
#0: ffff080084553240 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0xc0/0x13f0
#1: ffff800080485f08 (&kvm->arch.config_lock){+.+.}-{3:3}, at: kvm_arch_vcpu_ioctl+0xd60/0x1788
CPU: 19 PID: 13062 Comm: vgic_lpi_stress Tainted: G W O 6.8.0-dbg-DEV #1
Call trace:
dump_backtrace+0xf8/0x148
show_stack+0x20/0x38
dump_stack_lvl+0xb4/0xf8
dump_stack+0x18/0x40
__might_resched+0x248/0x2a0
__might_sleep+0x50/0x88
down_write+0x30/0x150
start_creating+0x90/0x1a0
__debugfs_create_file+0x5c/0x1b0
debugfs_create_file+0x34/0x48
kvm_reset_sys_regs+0x120/0x1e8
kvm_reset_vcpu+0x148/0x270
kvm_arch_vcpu_ioctl+0xddc/0x1788
kvm_vcpu_ioctl+0xb6c/0x13f0
__arm64_sys_ioctl+0x98/0xd8
invoke_syscall+0x48/0x108
el0_svc_common+0xb4/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x54/0x128
el0t_64_sync_handler+0x68/0xc0
el0t_64_sync+0x1a8/0x1b0
kvm_reset_vcpu() disables preemption as it needs to unload vCPU state
from the CPU to twiddle with it, which subsequently explodes when
taking the parent inode's rwsem while creating the idreg debugfs file.
Fix it by moving the initialization to kvm_arch_create_vm_debugfs().
Oliver Upton [Tue, 27 Feb 2024 09:41:14 +0000 (09:41 +0000)]
KVM: arm64: Fail the idreg iterator if idregs aren't initialized
Return an error to userspace if the VM's ID register values haven't been
initialized in preparation for changing the debugfs file initialization
order.
Oliver Upton [Wed, 21 Feb 2024 05:42:53 +0000 (05:42 +0000)]
KVM: arm64: vgic: Don't acquire the lpi_list_lock in vgic_put_irq()
The LPI xarray's xa_lock is sufficient for synchronizing writers when
freeing a given LPI. Furthermore, readers can only take a new reference
on an IRQ if it was already nonzero.
Stop taking the lpi_list_lock unnecessarily and get rid of
__vgic_put_lpi_locked().
Oliver Upton [Wed, 21 Feb 2024 05:42:52 +0000 (05:42 +0000)]
KVM: arm64: vgic: Ensure the irq refcount is nonzero when taking a ref
It will soon be possible for get() and put() calls to happen in
parallel, which means in most cases we must ensure the refcount is
nonzero when taking a new reference. Switch to using
vgic_try_get_irq_kref() where necessary, and document the few conditions
where an IRQ's refcount is guaranteed to be nonzero.
Oliver Upton [Wed, 21 Feb 2024 05:42:51 +0000 (05:42 +0000)]
KVM: arm64: vgic: Rely on RCU protection in vgic_get_lpi()
Stop acquiring the lpi_list_lock in favor of RCU for protecting
the read-side critical section in vgic_get_lpi(). In order for this to
be safe, we also need to be careful not to take a reference on an irq
with a refcount of 0, as it is about to be freed.
Oliver Upton [Wed, 21 Feb 2024 05:42:46 +0000 (05:42 +0000)]
KVM: arm64: vgic-v3: Iterate the xarray to find pending LPIs
Start walking the LPI xarray to find pending LPIs in preparation for
the removal of the LPI linked-list. Note that the 'basic' iterator
is chosen here as each iteration needs to drop the xarray read lock
(RCU) as reads/writes to guest memory can potentially block.
Oliver Upton [Wed, 21 Feb 2024 05:42:44 +0000 (05:42 +0000)]
KVM: arm64: vgic: Store LPIs in an xarray
Using a linked-list for LPIs is less than ideal as it of course requires
iterative searches to find a particular entry. An xarray is a better
data structure for this use case, as it provides faster searches and can
still handle a potentially sparse range of INTID allocations.
Start by storing LPIs in an xarray, punting usage of the xarray to a
subsequent change. The observant among you will notice that we added yet
another lock to the chain of locking order rules; document the ordering
of the xa_lock. Don't worry, we'll get rid of the lpi_list_lock one
day...
Oliver Upton [Fri, 16 Feb 2024 15:59:41 +0000 (15:59 +0000)]
KVM: Get rid of return value from kvm_arch_create_vm_debugfs()
The general expectation with debugfs is that any initialization failure
is nonfatal. Nevertheless, kvm_arch_create_vm_debugfs() allows
implementations to return an error and kvm_create_vm_debugfs() allows
that to fail VM creation.
Change to a void return to discourage architectures from making debugfs
failures fatal for the VM. Seems like everyone already had the right
idea, as all implementations already return 0 unconditionally.
Marc Zyngier [Thu, 22 Feb 2024 14:12:09 +0000 (14:12 +0000)]
KVM: arm64: Make build-time check of RES0/RES1 bits optional
In order to ease the transition towards a state of absolute
paranoia where all RES0/RES1 bits gets checked against what
KVM know of them, make the checks optional and guarded by a
config symbol (CONFIG_KVM_ARM64_RES_BITS_PARANOIA) default to n.
Marc Zyngier [Wed, 14 Feb 2024 13:18:26 +0000 (13:18 +0000)]
KVM: arm64: Snapshot all non-zero RES0/RES1 sysreg fields for later checking
As KVM now strongly relies on accurately handling the RES0/RES1 bits
on a number of paths, add a compile-time checker that will blow in
the face of the innocent bystander, should they try to sneak in an
update that changes any of these RES0/RES1 fields.
It is expected that such an update will come with the relevant
KVM update if needed.
Marc Zyngier [Wed, 14 Feb 2024 13:18:23 +0000 (13:18 +0000)]
KVM: arm64: Make PIR{,E0}_EL1 UNDEF if S1PIE is not advertised to the guest
As part of the ongoing effort to honor the guest configuration,
add the necessary checks to make PIR_EL1 and co UNDEF if not
advertised to the guest, and avoid context switching them.
Marc Zyngier [Wed, 14 Feb 2024 13:18:22 +0000 (13:18 +0000)]
KVM: arm64: Make TLBI OS/Range UNDEF if not advertised to the guest
Outer Shareable and Range TLBI instructions shouldn't be made available
to the guest if they are not advertised. Use FGU to disable those,
and set HCR_EL2.TLBIOS in the case the host doesn't have FGT. Note
that in that later case, we cannot efficiently disable TLBI Range
instructions, as this would require to trap all TLBIs.
Marc Zyngier [Wed, 14 Feb 2024 13:18:19 +0000 (13:18 +0000)]
KVM: arm64: Propagate and handle Fine-Grained UNDEF bits
In order to correctly honor our FGU bits, they must be converted
into a set of FGT bits. They get merged as part of the existing
FGT setting.
Similarly, the UNDEF injection phase takes place when handling
the trap.
This results in a bit of rework in the FGT macros in order to
help with the code generation, as burying per-CPU accesses in
macros results in a lot of expansion, not to mention the vcpu->kvm
access on nvhe (kern_hyp_va() is not optimisation-friendly).
Marc Zyngier [Wed, 14 Feb 2024 13:18:18 +0000 (13:18 +0000)]
KVM: arm64: Add Fine-Grained UNDEF tracking information
In order to efficiently handle system register access being disabled,
and this resulting in an UNDEF exception being injected, we introduce
the (slightly dubious) concept of Fine-Grained UNDEF, modeled after
the architectural Fine-Grained Traps.
For each FGT group, we keep a 64 bit word that has the exact same
bit assignment as the corresponding FGT register, where a 1 indicates
that trapping this register should result in an UNDEF exception being
reinjected.
So far, nothing populates this information, nor sets the corresponding
trap bits.
Marc Zyngier [Wed, 14 Feb 2024 13:18:17 +0000 (13:18 +0000)]
KVM: arm64: Rename __check_nv_sr_forward() to triage_sysreg_trap()
__check_nv_sr_forward() is not specific to NV anymore, and does
a lot more. Rename it to triage_sysreg_trap(), making it plain
that its role is to handle where an exception is to be handled.
Marc Zyngier [Wed, 14 Feb 2024 13:18:15 +0000 (13:18 +0000)]
KVM: arm64: Register AArch64 system register entries with the sysreg xarray
In order to reduce the number of lookups that we have to perform
when handling a sysreg, register each AArch64 sysreg descriptor
with the global xarray. The index of the descriptor is stored
as a 10 bit field in the data word.
Subsequent patches will retrieve and use the stored index.
Marc Zyngier [Wed, 14 Feb 2024 13:18:13 +0000 (13:18 +0000)]
KVM: arm64: nv: Move system instructions to their own sys_reg_desc array
As NV results in a bunch of system instructions being trapped, it makes
sense to pull the system instructions into their own little array, where
they will eventually be joined by AT, TLBI and a bunch of other CMOs.
Marc Zyngier [Wed, 14 Feb 2024 13:18:12 +0000 (13:18 +0000)]
KVM: arm64: Drop the requirement for XARRAY_MULTI
Now that we don't use xa_store_range() anymore, drop the added
complexity of XARRAY_MULTI for KVM. It is likely still pulled
in by other bits of the kernel though.
Marc Zyngier [Wed, 14 Feb 2024 13:18:11 +0000 (13:18 +0000)]
KVM: arm64: nv: Turn encoding ranges into discrete XArray stores
In order to be able to store different values for member of an
encoding range, replace xa_store_range() calls with discrete
xa_store() calls and an encoding iterator.
We end-up using a bit more memory, but we gain some flexibility
that we will make use of shortly.
Take this opportunity to tidy up the error handling path.
Negative trap bits are a massive pain. They are, on the surface,
indistinguishable from RES0 bits. Do you trap? or do you ignore?
Thankfully, we now have the right infrastructure to check for RES0
bits as long as the register is backed by VNCR, which is the case
for the FGT registers.
Use that information as a discriminant when handling a trap that
is potentially caused by a FGT.
There is no reason to have separate FGT group identifiers for
the debug fine grain trapping. The sole requirement is to provide
the *names* so that the SR_FGF() macro can do its magic of picking
the correct bit definition.
Marc Zyngier [Wed, 14 Feb 2024 13:18:08 +0000 (13:18 +0000)]
KVM: arm64: nv: Drop sanitised_sys_reg() helper
Now that we have the infrastructure to enforce a sanitised register
value depending on the VM configuration, drop the helper that only
used the architectural RES0 value.
Marc Zyngier [Wed, 14 Feb 2024 13:18:06 +0000 (13:18 +0000)]
KVM: arm64: nv: Add sanitising to VNCR-backed FGT sysregs
Fine Grained Traps are controlled by a whole bunch of features.
Each one of them must be checked and the corresponding masks
computed so that we don't let the guest apply traps it shouldn't
be using.
This takes care of HFG[IRW]TR_EL2, HDFG[RW]TR_EL2, and HAFGRTR_EL2.
Marc Zyngier [Wed, 14 Feb 2024 13:18:04 +0000 (13:18 +0000)]
KVM: arm64: nv: Add sanitising to VNCR-backed sysregs
VNCR-backed "registers" are actually only memory. Which means that
there is zero control over what the guest can write, and that it
is the hypervisor's job to actually sanitise the content of the
backing store. Yeah, this is fun.
In order to preserve some form of sanity, add a repainting mechanism
that makes use of a per-VM set of RES0/RES1 masks, one pair per VNCR
register. These masks get applied on access to the backing store via
__vcpu_sys_reg(), ensuring that the state that is consumed by KVM is
correct.
So far, nothing populates these masks, but stay tuned.
Marc Zyngier [Wed, 14 Feb 2024 13:18:03 +0000 (13:18 +0000)]
KVM: arm64: Add feature checking helpers
In order to make it easier to check whether a particular feature
is exposed to a guest, add a new set of helpers, with kvm_has_feat()
being the most useful.
Let's start making use of them in the PMU code (courtesy of Oliver).
Follow-up changes will introduce additional use patterns.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Co-developed--by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240214131827.2856277-3-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Wed, 14 Feb 2024 13:18:02 +0000 (13:18 +0000)]
arm64: sysreg: Add missing ID_AA64ISAR[13]_EL1 fields and variants
Despite having the control bits for FEAT_SPECRES and FEAT_PACM,
the ID registers fields are either incomplete or missing.
Fix it.
Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240214131827.2856277-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Thu, 15 Feb 2024 01:49:54 +0000 (01:49 +0000)]
arm64: cpufeatures: Fix FEAT_NV check when checking for FEAT_NV1
Using this_cpu_has_cap() has the potential to go wrong when
used system-wide on a preemptible kernel. Instead, use the
__system_matches_cap() helper when checking for FEAT_NV in the
FEAT_NV1 probing helper.
Fixes: 3673d01a2f55 ("arm64: cpufeatures: Only check for NV1 if NV is present") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/kvmarm/86bk8k5ts3.wl-maz@kernel.org/ Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Oliver Upton [Mon, 12 Feb 2024 21:09:33 +0000 (21:09 +0000)]
KVM: selftests: Print timer ctl register in ISTATUS assertion
Zenghui noted that the test assertion for the ISTATUS bit is printing
the current timer value instead of the control register in the case of
failure. While the assertion is sound, printing CNT isn't informative.
Change things around to actually print the CTL register value instead.
Sean Christopherson [Fri, 2 Feb 2024 23:46:03 +0000 (15:46 -0800)]
KVM: selftests: Fix GUEST_PRINTF() format warnings in ARM code
Fix a pile of -Wformat warnings in the KVM ARM selftests code, almost all
of which are benign "long" versus "long long" issues (selftests are 64-bit
only, and the guest printf code treats "ll" the same as "l"). The code
itself isn't problematic, but the warnings make it impossible to build ARM
selftests with -Werror, which does detect real issues from time to time.
Opportunistically have GUEST_ASSERT_BITMAP_REG() interpret set_expected,
which is a bool, as an unsigned decimal value, i.e. have it print '0' or
'1' instead of '0x0' or '0x1'.
Joey Gouly [Thu, 8 Feb 2024 10:54:21 +0000 (10:54 +0000)]
KVM: arm64: add comments to __kern_hyp_va
Document this function a little, to make it easier to understand.
The assembly comments were copied from the kern_hyp_va asm macro.
Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240208105422.3444159-2-joey.gouly@arm.com
[oliver: migrate a bit more detail from the asm variant] Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Joey Gouly [Fri, 9 Feb 2024 10:37:19 +0000 (10:37 +0000)]
KVM: arm64: print Hyp mode
Print which of the hyp modes is being used (hVHE, nVHE).
Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240209103719.3813599-1-joey.gouly@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Mon, 12 Feb 2024 14:47:35 +0000 (14:47 +0000)]
arm64: cpufeatures: Add missing ID_AA64MMFR4_EL1 to __read_sysreg_by_encoding()
When triggering a CPU hotplug scenario, we reparse the CPU feature
with SCOPE_LOCAL_CPU, for which we use __read_sysreg_by_encoding()
to get the HW value for this CPU.
As it turns out, we're missing the handling for ID_AA64MMFR4_EL1,
and trigger a BUG(). Funnily enough, Marek isn't completely happy
about that.
Add the damn register to the list.
Fixes: 805bb61f8279 ("arm64: cpufeature: Add ID_AA64MMFR4_EL1 handling") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240212144736.1933112-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Mon, 22 Jan 2024 18:13:44 +0000 (18:13 +0000)]
KVM: arm64: Handle Apple M2 as not having HCR_EL2.NV1 implemented
Although the Apple M2 family of CPUs can have HCR_EL2.NV1 being
set and clear, with the change in trap behaviour being OK, they
explode spectacularily on an EL2 S1 page table using the nVHE
format. This is no good.
Let's pretend this HW doesn't have NV1, and move along.
Marc Zyngier [Mon, 22 Jan 2024 18:13:43 +0000 (18:13 +0000)]
KVM: arm64: Force guest's HCR_EL2.E2H RES1 when NV1 is not implemented
If NV1 isn't supported on a system, make sure we always evaluate
the guest's HCR_EL2.E2H as RES1, irrespective of what the guest
may have written there.
Marc Zyngier [Mon, 22 Jan 2024 18:13:41 +0000 (18:13 +0000)]
arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is negative
For CPUs that have ID_AA64MMFR4_EL1.E2H0 as negative, it is important
to avoid the boot path that sets HCR_EL2.E2H=0. Fortunately, we
already have this path to cope with fruity CPUs.
Tweak init_el2 to look at ID_AA64MMFR4_EL1.E2H0 first.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-8-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Mon, 22 Jan 2024 18:13:40 +0000 (18:13 +0000)]
arm64: cpufeature: Detect HCR_EL2.NV1 being RES0
A variant of FEAT_E2H0 not being implemented exists in the form of
HCR_EL2.E2H being RES1 *and* HCR_EL2.NV1 being RES0 (indicating that
only VHE is supported on the host and nested guests).
Add the necessary infrastructure for this new CPU capability.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-7-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Miguel Luis <miguel.luis@oracle.com> Link: https://lore.kernel.org/r/20240122181344.258974-5-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Mon, 22 Jan 2024 18:13:37 +0000 (18:13 +0000)]
arm64: cpufeature: Correctly display signed override values
When a field gets overriden, the kernel indicates the result of
the override in dmesg. This works well with unsigned fields, but
results in a pretty ugly output when the field is signed.
Truncate the field to its width before displaying it.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20240122181344.258974-4-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Marc Zyngier [Mon, 22 Jan 2024 18:13:36 +0000 (18:13 +0000)]
arm64: cpufeatures: Correctly handle signed values
Although we've had signed values for some features such as PMUv3
and FP, the code that handles the comparaison with some limit
has a couple of annoying issues:
- the min_field_value is always unsigned, meaning that we cannot
easily compare it with a negative value
- it is not possible to have a range of values, let alone a range
of negative values
Fix this by:
- adding an upper limit to the comparison, defaulting to all bits
being set to the maximum positive value
- ensuring that the signess of the min and max values are taken into
account
A ARM64_CPUID_FIELDS_NEG() macro is provided for signed features, but
nothing is using it yet.
Jing Zhang [Mon, 15 Jan 2024 22:02:09 +0000 (14:02 -0800)]
KVM: arm64: selftests: Handle feature fields with nonzero minimum value correctly
There are some feature fields with nonzero minimum valid value. Make
sure get_safe_value() won't return invalid field values for them.
Also fix a bug that wrongly uses the feature bits type as the feature
bits sign causing all fields as signed in the get_safe_value() and
get_invalid_value().
Fixes: 54a9ea73527d ("KVM: arm64: selftests: Test for setting ID register from usersapce") Reported-by: Zenghui Yu <yuzenghui@huawei.com> Reported-by: Itaru Kitayama <itaru.kitayama@linux.dev> Tested-by: Itaru Kitayama <itaru.kitayama@fujitsu.com> Signed-off-by: Jing Zhang <jingzhangos@google.com> Link: https://lore.kernel.org/r/20240115220210.3966064-2-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Linus Torvalds [Sun, 21 Jan 2024 22:01:12 +0000 (14:01 -0800)]
Merge tag 'bcachefs-2024-01-21' of https://evilpiepirate.org/git/bcachefs
Pull more bcachefs updates from Kent Overstreet:
"Some fixes, Some refactoring, some minor features:
- Assorted prep work for disk space accounting rewrite
- BTREE_TRIGGER_ATOMIC: after combining our trigger callbacks, this
makes our trigger context more explicit
- A few fixes to avoid excessive transaction restarts on
multithreaded workloads: fstests (in addition to ktest tests) are
now checking slowpath counters, and that's shaking out a few bugs
- Assorted tracepoint improvements
- Starting to break up bcachefs_format.h and move on disk types so
they're with the code they belong to; this will make room to start
documenting the on disk format better.
- A few minor fixes"
* tag 'bcachefs-2024-01-21' of https://evilpiepirate.org/git/bcachefs: (46 commits)
bcachefs: Improve inode_to_text()
bcachefs: logged_ops_format.h
bcachefs: reflink_format.h
bcachefs; extents_format.h
bcachefs: ec_format.h
bcachefs: subvolume_format.h
bcachefs: snapshot_format.h
bcachefs: alloc_background_format.h
bcachefs: xattr_format.h
bcachefs: dirent_format.h
bcachefs: inode_format.h
bcachefs; quota_format.h
bcachefs: sb-counters_format.h
bcachefs: counters.c -> sb-counters.c
bcachefs: comment bch_subvolume
bcachefs: bch_snapshot::btime
bcachefs: add missing __GFP_NOWARN
bcachefs: opts->compression can now also be applied in the background
bcachefs: Prep work for variable size btree node buffers
bcachefs: grab s_umount only if snapshotting
...
Linus Torvalds [Sun, 21 Jan 2024 19:14:40 +0000 (11:14 -0800)]
Merge tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
"Updates for time and clocksources:
- A fix for the idle and iowait time accounting vs CPU hotplug.
The time is reset on CPU hotplug which makes the accumulated
systemwide time jump backwards.
- Assorted fixes and improvements for clocksource/event drivers"
* tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug
clocksource/drivers/ep93xx: Fix error handling during probe
clocksource/drivers/cadence-ttc: Fix some kernel-doc warnings
clocksource/drivers/timer-ti-dm: Fix make W=n kerneldoc warnings
clocksource/timer-riscv: Add riscv_clock_shutdown callback
dt-bindings: timer: Add StarFive JH8100 clint
dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs
Kent Overstreet [Tue, 16 Jan 2024 21:20:21 +0000 (16:20 -0500)]
bcachefs: opts->compression can now also be applied in the background
The "apply this compression method in the background" paths now use the
compression option if background_compression is not set; this means that
setting or changing the compression option will cause existing data to
be compressed accordingly in the background.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Kent Overstreet [Tue, 16 Jan 2024 18:29:59 +0000 (13:29 -0500)]
bcachefs: Prep work for variable size btree node buffers
bcachefs btree nodes are big - typically 256k - and btree roots are
pinned in memory. As we're now up to 18 btrees, we now have significant
memory overhead in mostly empty btree roots.
And in the future we're going to start enforcing that certain btree node
boundaries exist, to solve lock contention issues - analagous to XFS's
AGIs.
Thus, we need to start allocating smaller btree node buffers when we
can. This patch changes code that refers to the filesystem constant
c->opts.btree_node_size to refer to the btree node buffer size -
btree_buf_bytes() - where appropriate.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In __bch2_ioctl_subvolume_create(), we grab s_umount unconditionally
and unlock it at the end of the function. There is a comment
"why do we need this lock?" about the lock coming from
commit 42d237320e98 ("bcachefs: Snapshot creation, deletion")
The reason is that __bch2_ioctl_subvolume_create() calls
sync_inodes_sb() which enforce locked s_umount to writeback all dirty
nodes before doing snapshot works.
Fix it by read locking s_umount for snapshotting only and unlocking
s_umount after sync_inodes_sb().
Signed-off-by: Su Yue <glass.su@suse.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Colin Ian King [Tue, 16 Jan 2024 11:07:23 +0000 (11:07 +0000)]
bcachefs: remove redundant variable tmp
The variable tmp is being assigned a value but it isn't being
read afterwards. The assignment is redundant and so tmp can be
removed.
Cleans up clang scan build warning:
warning: Although the value stored to 'ret' is used in the enclosing
expression, the value is never actually read from 'ret'
[deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Kent Overstreet [Tue, 16 Jan 2024 01:37:23 +0000 (20:37 -0500)]
bcachefs: Fix excess transaction restarts in __bchfs_fallocate()
drop_locks_do() should not be used in a fastpath without first trying
the do in nonblocking mode - the unlock and relock will cause excessive
transaction restarts and potentially livelocking with other threads that
are contending for the same locks.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Kent Overstreet [Mon, 15 Jan 2024 22:59:51 +0000 (17:59 -0500)]
bcachefs: Better journal tracepoints
Factor out bch2_journal_bufs_to_text(), and use it in the
journal_entry_full() tracepoint; when we can't get a journal reservation
we need to know the outstanding journal entry sizes to know if the
problem is due to excessive flushing.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Kent Overstreet [Mon, 15 Jan 2024 22:56:22 +0000 (17:56 -0500)]
bcachefs: Avoid flushing the journal in the discard path
When issuing discards, we may need to flush the journal if there's too
many buckets that can't be discarded until a journal flush.
But the heuristic was bad; we should be comparing the number of buckets
that need to flushes against the number of free buckets, not the number
of buckets we saw.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>