arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted

__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in
HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host
traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The
kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU
driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a
write from EL0 reaches the trap and takes the host down without a panic
message.

Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already
does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9
bits.

Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9")
Cc: stable@vger.kernel.org
Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 107 insertions, 0 deletions

diff --git a/Documentation/driver-api/infrastructure.rst b/Documentation/driver-api/infrastructure.rst
new file mode 100644
index 000000000..ac73e60fb
--- /dev/null
+++ b/Documentation/driver-api/infrastructure.rst
@@ -0,0 +1,107 @@
+Device drivers infrastructure
+=============================
+
+The Basic Device Driver-Model Structures
+----------------------------------------
+
+.. kernel-doc:: include/linux/device.h
+   :internal:
+   :no-identifiers: device_link_state
+
+.. kernel-doc:: include/linux/device/bus.h
+   :identifiers: bus_type bus_notifier_event
+
+.. kernel-doc:: include/linux/device/class.h
+   :identifiers: class
+
+.. kernel-doc:: include/linux/device/driver.h
+   :identifiers: probe_type device_driver
+
+.. kernel-doc:: include/linux/property.h
+
+.. kernel-doc:: include/linux/fwnode.h
+
+Device Drivers Base
+-------------------
+
+.. kernel-doc:: drivers/base/init.c
+   :internal:
+
+.. kernel-doc:: include/linux/device/driver.h
+   :no-identifiers: probe_type device_driver
+
+.. kernel-doc:: drivers/base/driver.c
+   :export:
+
+.. kernel-doc:: drivers/base/core.c
+   :export:
+
+.. kernel-doc:: drivers/base/syscore.c
+   :export:
+
+.. kernel-doc:: include/linux/device/class.h
+   :no-identifiers: class
+
+.. kernel-doc:: drivers/base/class.c
+   :export:
+
+.. kernel-doc:: include/linux/device/faux.h
+   :internal:
+
+.. kernel-doc:: drivers/base/faux.c
+   :export:
+
+.. kernel-doc:: drivers/base/node.c
+   :internal:
+
+.. kernel-doc:: drivers/base/transport_class.c
+   :export:
+
+.. kernel-doc:: drivers/base/dd.c
+   :export:
+
+.. kernel-doc:: include/linux/platform_device.h
+   :internal:
+
+.. kernel-doc:: drivers/base/platform.c
+   :export:
+
+.. kernel-doc:: include/linux/device/bus.h
+   :no-identifiers: bus_type bus_notifier_event
+
+.. kernel-doc:: drivers/base/bus.c
+   :export:
+
+Device Drivers DMA Management
+-----------------------------
+
+.. kernel-doc:: kernel/dma/mapping.c
+   :export:
+
+Device drivers PnP support
+--------------------------
+
+.. kernel-doc:: drivers/pnp/core.c
+   :internal:
+
+.. kernel-doc:: drivers/pnp/card.c
+   :export:
+
+.. kernel-doc:: drivers/pnp/driver.c
+   :internal:
+
+.. kernel-doc:: drivers/pnp/manager.c
+   :export:
+
+.. kernel-doc:: drivers/pnp/support.c
+   :export:
+
+Userspace IO devices
+--------------------
+
+.. kernel-doc:: drivers/uio/uio.c
+   :export:
+
+.. kernel-doc:: include/linux/uio_driver.h
+   :internal:
+