Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Move the bpf verifier trace check into the new switch statement in
HEAD.

Resolve the overlapping changes in hinic, where bug fixes overlap
the addition of VF support.

Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/core-api/printk-formats.rst

@@ -112,6 +112,20 @@ used when printing stack backtraces. The specifier takes into
 consideration the effect of compiler optimisations which may occur
 when tail-calls are used and marked with the noreturn GCC attribute.
 
+Probed Pointers from BPF / tracing
+----------------------------------
+
+::
+
+	%pks	kernel string
+	%pus	user string
+
+The ``k`` and ``u`` specifiers are used for printing prior probed memory from
+either kernel memory (k) or user memory (u). The subsequent ``s`` specifier
+results in printing a string. For direct use in regular vsnprintf() the (k)
+and (u) annotation is ignored, however, when used out of BPF's bpf_trace_printk(),
+for example, it reads the memory it is pointing to without faulting.
+
 Kernel Pointers
 ---------------
 

Documentation/virt/kvm/index.rst

@@ -28,3 +28,5 @@ KVM
    arm/index
 
    devices/index
+
+   running-nested-guests

Documentation/virt/kvm/running-nested-guests.rst

@@ -0,0 +1,276 @@
+==============================
+Running nested guests with KVM
+==============================
+
+A nested guest is the ability to run a guest inside another guest (it
+can be KVM-based or a different hypervisor).  The straightforward
+example is a KVM guest that in turn runs on a KVM guest (the rest of
+this document is built on this example)::
+
+              .----------------.  .----------------.
+              |                |  |                |
+              |      L2        |  |      L2        |
+              | (Nested Guest) |  | (Nested Guest) |
+              |                |  |                |
+              |----------------'--'----------------|
+              |                                    |
+              |       L1 (Guest Hypervisor)        |
+              |          KVM (/dev/kvm)            |
+              |                                    |
+      .------------------------------------------------------.
+      |                 L0 (Host Hypervisor)                 |
+      |                    KVM (/dev/kvm)                    |
+      |------------------------------------------------------|
+      |        Hardware (with virtualization extensions)     |
+      '------------------------------------------------------'
+
+Terminology:
+
+- L0 – level-0; the bare metal host, running KVM
+
+- L1 – level-1 guest; a VM running on L0; also called the "guest
+  hypervisor", as it itself is capable of running KVM.
+
+- L2 – level-2 guest; a VM running on L1, this is the "nested guest"
+
+.. note:: The above diagram is modelled after the x86 architecture;
+          s390x, ppc64 and other architectures are likely to have
+          a different design for nesting.
+
+          For example, s390x always has an LPAR (LogicalPARtition)
+          hypervisor running on bare metal, adding another layer and
+          resulting in at least four levels in a nested setup — L0 (bare
+          metal, running the LPAR hypervisor), L1 (host hypervisor), L2
+          (guest hypervisor), L3 (nested guest).
+
+          This document will stick with the three-level terminology (L0,
+          L1, and L2) for all architectures; and will largely focus on
+          x86.
+
+
+Use Cases
+---------
+
+There are several scenarios where nested KVM can be useful, to name a
+few:
+
+- As a developer, you want to test your software on different operating
+  systems (OSes).  Instead of renting multiple VMs from a Cloud
+  Provider, using nested KVM lets you rent a large enough "guest
+  hypervisor" (level-1 guest).  This in turn allows you to create
+  multiple nested guests (level-2 guests), running different OSes, on
+  which you can develop and test your software.
+
+- Live migration of "guest hypervisors" and their nested guests, for
+  load balancing, disaster recovery, etc.
+
+- VM image creation tools (e.g. ``virt-install``,  etc) often run
+  their own VM, and users expect these to work inside a VM.
+
+- Some OSes use virtualization internally for security (e.g. to let
+  applications run safely in isolation).
+
+
+Enabling "nested" (x86)
+-----------------------
+
+From Linux kernel v4.19 onwards, the ``nested`` KVM parameter is enabled
+by default for Intel and AMD.  (Though your Linux distribution might
+override this default.)
+
+In case you are running a Linux kernel older than v4.19, to enable
+nesting, set the ``nested`` KVM module parameter to ``Y`` or ``1``.  To
+persist this setting across reboots, you can add it in a config file, as
+shown below:
+
+1. On the bare metal host (L0), list the kernel modules and ensure that
+   the KVM modules::
+
+    $ lsmod | grep -i kvm
+    kvm_intel             133627  0
+    kvm                   435079  1 kvm_intel
+
+2. Show information for ``kvm_intel`` module::
+
+    $ modinfo kvm_intel | grep -i nested
+    parm:           nested:bool
+
+3. For the nested KVM configuration to persist across reboots, place the
+   below in ``/etc/modprobed/kvm_intel.conf`` (create the file if it
+   doesn't exist)::
+
+    $ cat /etc/modprobe.d/kvm_intel.conf
+    options kvm-intel nested=y
+
+4. Unload and re-load the KVM Intel module::
+
+    $ sudo rmmod kvm-intel
+    $ sudo modprobe kvm-intel
+
+5. Verify if the ``nested`` parameter for KVM is enabled::
+
+    $ cat /sys/module/kvm_intel/parameters/nested
+    Y
+
+For AMD hosts, the process is the same as above, except that the module
+name is ``kvm-amd``.
+
+
+Additional nested-related kernel parameters (x86)
+-------------------------------------------------
+
+If your hardware is sufficiently advanced (Intel Haswell processor or
+higher, which has newer hardware virt extensions), the following
+additional features will also be enabled by default: "Shadow VMCS
+(Virtual Machine Control Structure)", APIC Virtualization on your bare
+metal host (L0).  Parameters for Intel hosts::
+
+    $ cat /sys/module/kvm_intel/parameters/enable_shadow_vmcs
+    Y
+
+    $ cat /sys/module/kvm_intel/parameters/enable_apicv
+    Y
+
+    $ cat /sys/module/kvm_intel/parameters/ept
+    Y
+
+.. note:: If you suspect your L2 (i.e. nested guest) is running slower,
+          ensure the above are enabled (particularly
+          ``enable_shadow_vmcs`` and ``ept``).
+
+
+Starting a nested guest (x86)
+-----------------------------
+
+Once your bare metal host (L0) is configured for nesting, you should be
+able to start an L1 guest with::
+
+    $ qemu-kvm -cpu host [...]
+
+The above will pass through the host CPU's capabilities as-is to the
+gues); or for better live migration compatibility, use a named CPU
+model supported by QEMU. e.g.::
+
+    $ qemu-kvm -cpu Haswell-noTSX-IBRS,vmx=on
+
+then the guest hypervisor will subsequently be capable of running a
+nested guest with accelerated KVM.
+
+
+Enabling "nested" (s390x)
+-------------------------
+
+1. On the host hypervisor (L0), enable the ``nested`` parameter on
+   s390x::
+
+    $ rmmod kvm
+    $ modprobe kvm nested=1
+
+.. note:: On s390x, the kernel parameter ``hpage`` is mutually exclusive
+          with the ``nested`` paramter — i.e. to be able to enable
+          ``nested``, the ``hpage`` parameter *must* be disabled.
+
+2. The guest hypervisor (L1) must be provided with the ``sie`` CPU
+   feature — with QEMU, this can be done by using "host passthrough"
+   (via the command-line ``-cpu host``).
+
+3. Now the KVM module can be loaded in the L1 (guest hypervisor)::
+
+    $ modprobe kvm
+
+
+Live migration with nested KVM
+------------------------------
+
+Migrating an L1 guest, with a  *live* nested guest in it, to another
+bare metal host, works as of Linux kernel 5.3 and QEMU 4.2.0 for
+Intel x86 systems, and even on older versions for s390x.
+
+On AMD systems, once an L1 guest has started an L2 guest, the L1 guest
+should no longer be migrated or saved (refer to QEMU documentation on
+"savevm"/"loadvm") until the L2 guest shuts down.  Attempting to migrate
+or save-and-load an L1 guest while an L2 guest is running will result in
+undefined behavior.  You might see a ``kernel BUG!`` entry in ``dmesg``, a
+kernel 'oops', or an outright kernel panic.  Such a migrated or loaded L1
+guest can no longer be considered stable or secure, and must be restarted.
+Migrating an L1 guest merely configured to support nesting, while not
+actually running L2 guests, is expected to function normally even on AMD
+systems but may fail once guests are started.
+
+Migrating an L2 guest is always expected to succeed, so all the following
+scenarios should work even on AMD systems:
+
+- Migrating a nested guest (L2) to another L1 guest on the *same* bare
+  metal host.
+
+- Migrating a nested guest (L2) to another L1 guest on a *different*
+  bare metal host.
+
+- Migrating a nested guest (L2) to a bare metal host.
+
+Reporting bugs from nested setups
+-----------------------------------
+
+Debugging "nested" problems can involve sifting through log files across
+L0, L1 and L2; this can result in tedious back-n-forth between the bug
+reporter and the bug fixer.
+
+- Mention that you are in a "nested" setup.  If you are running any kind
+  of "nesting" at all, say so.  Unfortunately, this needs to be called
+  out because when reporting bugs, people tend to forget to even
+  *mention* that they're using nested virtualization.
+
+- Ensure you are actually running KVM on KVM.  Sometimes people do not
+  have KVM enabled for their guest hypervisor (L1), which results in
+  them running with pure emulation or what QEMU calls it as "TCG", but
+  they think they're running nested KVM.  Thus confusing "nested Virt"
+  (which could also mean, QEMU on KVM) with "nested KVM" (KVM on KVM).
+
+Information to collect (generic)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The following is not an exhaustive list, but a very good starting point:
+
+  - Kernel, libvirt, and QEMU version from L0
+
+  - Kernel, libvirt and QEMU version from L1
+
+  - QEMU command-line of L1 -- when using libvirt, you'll find it here:
+    ``/var/log/libvirt/qemu/instance.log``
+
+  - QEMU command-line of L2 -- as above, when using libvirt, get the
+    complete libvirt-generated QEMU command-line
+
+  - ``cat /sys/cpuinfo`` from L0
+
+  - ``cat /sys/cpuinfo`` from L1
+
+  - ``lscpu`` from L0
+
+  - ``lscpu`` from L1
+
+  - Full ``dmesg`` output from L0
+
+  - Full ``dmesg`` output from L1
+
+x86-specific info to collect
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Both the below commands, ``x86info`` and ``dmidecode``, should be
+available on most Linux distributions with the same name:
+
+  - Output of: ``x86info -a`` from L0
+
+  - Output of: ``x86info -a`` from L1
+
+  - Output of: ``dmidecode`` from L0
+
+  - Output of: ``dmidecode`` from L1
+
+s390x-specific info to collect
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Along with the earlier mentioned generic details, the below is
+also recommended:
+
+  - ``/proc/sysinfo`` from L1; this will also include the info from L0

MAINTAINERS

@@ -3936,11 +3936,9 @@ F:	arch/powerpc/platforms/cell/
 CEPH COMMON CODE (LIBCEPH)
 M:	Ilya Dryomov <idryomov@gmail.com>
 M:	Jeff Layton <jlayton@kernel.org>
-M:	Sage Weil <sage@redhat.com>
 L:	ceph-devel@vger.kernel.org
 S:	Supported
 W:	http://ceph.com/
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git
 T:	git git://github.com/ceph/ceph-client.git
 F:	include/linux/ceph/
 F:	include/linux/crush/
@@ -3948,12 +3946,10 @@ F:	net/ceph/
 
 CEPH DISTRIBUTED FILE SYSTEM CLIENT (CEPH)
 M:	Jeff Layton <jlayton@kernel.org>
-M:	Sage Weil <sage@redhat.com>
 M:	Ilya Dryomov <idryomov@gmail.com>
 L:	ceph-devel@vger.kernel.org
 S:	Supported
 W:	http://ceph.com/
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git
 T:	git git://github.com/ceph/ceph-client.git
 F:	Documentation/filesystems/ceph.rst
 F:	fs/ceph/
@@ -7119,9 +7115,10 @@ F:	include/uapi/asm-generic/
 
 GENERIC PHY FRAMEWORK
 M:	Kishon Vijay Abraham I <kishon@ti.com>
+M:	Vinod Koul <vkoul@kernel.org>
 L:	linux-kernel@vger.kernel.org
 S:	Supported
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/kishon/linux-phy.git
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy.git
 F:	Documentation/devicetree/bindings/phy/
 F:	drivers/phy/
 F:	include/linux/phy/
@@ -7746,11 +7743,6 @@ L:	platform-driver-x86@vger.kernel.org
 S:	Orphan
 F:	drivers/platform/x86/tc1100-wmi.c
 
-HP100:	Driver for HP 10/100 Mbit/s Voice Grade Network Adapter Series
-M:	Jaroslav Kysela <perex@perex.cz>
-S:	Obsolete
-F:	drivers/staging/hp/hp100.*
-
 HPET:	High Precision Event Timers driver
 M:	Clemens Ladisch <clemens@ladisch.de>
 S:	Maintained
@@ -11718,8 +11710,9 @@ F:	net/core/drop_monitor.c
 
 NETWORKING DRIVERS
 M:	"David S. Miller" <davem@davemloft.net>
+M:	Jakub Kicinski <kuba@kernel.org>
 L:	netdev@vger.kernel.org
-S:	Odd Fixes
+S:	Maintained
 W:	http://www.linuxfoundation.org/en/Net
 Q:	http://patchwork.ozlabs.org/project/netdev/list/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git
@@ -14102,12 +14095,10 @@ F:	drivers/media/radio/radio-tea5777.c
 
 RADOS BLOCK DEVICE (RBD)
 M:	Ilya Dryomov <idryomov@gmail.com>
-M:	Sage Weil <sage@redhat.com>
 R:	Dongsheng Yang <dongsheng.yang@easystack.cn>
 L:	ceph-devel@vger.kernel.org
 S:	Supported
 W:	http://ceph.com/
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git
 T:	git git://github.com/ceph/ceph-client.git
 F:	Documentation/ABI/testing/sysfs-bus-rbd
 F:	drivers/block/rbd.c
@@ -14644,6 +14635,7 @@ F:	drivers/iommu/s390-iommu.c
 
 S390 IUCV NETWORK LAYER
 M:	Julian Wiedmann <jwi@linux.ibm.com>
+M:	Karsten Graul <kgraul@linux.ibm.com>
 M:	Ursula Braun <ubraun@linux.ibm.com>
 L:	linux-s390@vger.kernel.org
 S:	Supported
@@ -14654,6 +14646,7 @@ F:	net/iucv/
 
 S390 NETWORK DRIVERS
 M:	Julian Wiedmann <jwi@linux.ibm.com>
+M:	Karsten Graul <kgraul@linux.ibm.com>
 M:	Ursula Braun <ubraun@linux.ibm.com>
 L:	linux-s390@vger.kernel.org
 S:	Supported

Makefile

@@ -2,7 +2,7 @@
 VERSION = 5
 PATCHLEVEL = 7
 SUBLEVEL = 0
-EXTRAVERSION = -rc4
+EXTRAVERSION = -rc5
 NAME = Kleptomaniac Octopus
 
 # *DOCUMENTATION*
@@ -729,10 +729,6 @@ else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 KBUILD_CFLAGS += -Os
 endif
 
-ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED
-KBUILD_CFLAGS   += -Wno-maybe-uninitialized
-endif
-
 # Tell gcc to never replace conditional load with a non-conditional one
 KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
 KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
@@ -881,6 +877,17 @@ KBUILD_CFLAGS += -Wno-pointer-sign
 # disable stringop warnings in gcc 8+
 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 
+# We'll want to enable this eventually, but it's not going away for 5.7 at least
+KBUILD_CFLAGS += $(call cc-disable-warning, zero-length-bounds)
+KBUILD_CFLAGS += $(call cc-disable-warning, array-bounds)
+KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
+
+# Another good warning that we'll want to enable eventually
+KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
+
+# Enabled with W=2, disabled by default as noisy
+KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized)
+
 # disable invalid "can't wrap" optimizations for signed / pointers
 KBUILD_CFLAGS	+= $(call cc-option,-fno-strict-overflow)
 

arch/arm/Kconfig

@@ -12,6 +12,7 @@ config ARM
 	select ARCH_HAS_KEEPINITRD
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
+	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
 	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
 	select ARCH_HAS_PHYS_TO_DMA
 	select ARCH_HAS_SETUP_DMA_OPS

arch/arm/configs/keystone_defconfig

@@ -147,6 +147,7 @@ CONFIG_I2C_DAVINCI=y
 CONFIG_SPI=y
 CONFIG_SPI_DAVINCI=y
 CONFIG_SPI_SPIDEV=y
+CONFIG_PTP_1588_CLOCK=y
 CONFIG_PINCTRL_SINGLE=y
 CONFIG_GPIOLIB=y
 CONFIG_GPIO_SYSFS=y

arch/arm/configs/omap2plus_defconfig

@@ -274,6 +274,7 @@ CONFIG_SPI_TI_QSPI=m
 CONFIG_HSI=m
 CONFIG_OMAP_SSI=m
 CONFIG_SSI_PROTOCOL=m
+CONFIG_PTP_1588_CLOCK=y
 CONFIG_PINCTRL_SINGLE=y
 CONFIG_DEBUG_GPIO=y
 CONFIG_GPIO_SYSFS=y

arch/arm/include/asm/futex.h

@@ -165,8 +165,13 @@ arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
 	preempt_enable();
 #endif
 
-	if (!ret)
-		*oval = oldval;
+	/*
+	 * Store unconditionally. If ret != 0 the extra store is the least
+	 * of the worries but GCC cannot figure out that __futex_atomic_op()
+	 * is either setting ret to -EFAULT or storing the old value in
+	 * oldval which results in a uninitialized warning at the call site.
+	 */
+	*oval = oldval;
 
 	return ret;
 }

arch/arm64/Kconfig

@@ -20,6 +20,7 @@ config ARM64
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_KEEPINITRD
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
+	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
 	select ARCH_HAS_PTE_DEVMAP
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_SETUP_DMA_OPS

arch/arm64/kernel/machine_kexec.c

@@ -177,6 +177,7 @@ void machine_kexec(struct kimage *kimage)
 	 * the offline CPUs. Therefore, we must use the __* variant here.
 	 */
 	__flush_icache_range((uintptr_t)reboot_code_buffer,
+			     (uintptr_t)reboot_code_buffer +
 			     arm64_relocate_new_kernel_size);
 
 	/* Flush the kimage list and its buffers. */

arch/arm64/kvm/guest.c

@@ -200,6 +200,13 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 	}
 
 	memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
+
+	if (*vcpu_cpsr(vcpu) & PSR_MODE32_BIT) {
+		int i;
+
+		for (i = 0; i < 16; i++)
+			*vcpu_reg32(vcpu, i) = (u32)*vcpu_reg32(vcpu, i);
+	}
 out:
 	return err;
 }

arch/arm64/kvm/hyp/entry.S

@@ -18,6 +18,7 @@
 
 #define CPU_GP_REG_OFFSET(x)	(CPU_GP_REGS + x)
 #define CPU_XREG_OFFSET(x)	CPU_GP_REG_OFFSET(CPU_USER_PT_REGS + 8*x)
+#define CPU_SP_EL0_OFFSET	(CPU_XREG_OFFSET(30) + 8)
 
 	.text
 	.pushsection	.hyp.text, "ax"
@@ -47,6 +48,16 @@
 	ldp	x29, lr,  [\ctxt, #CPU_XREG_OFFSET(29)]
 .endm
 
+.macro save_sp_el0 ctxt, tmp
+	mrs	\tmp,	sp_el0
+	str	\tmp,	[\ctxt, #CPU_SP_EL0_OFFSET]
+.endm
+
+.macro restore_sp_el0 ctxt, tmp
+	ldr	\tmp,	  [\ctxt, #CPU_SP_EL0_OFFSET]
+	msr	sp_el0, \tmp
+.endm
+
 /*
  * u64 __guest_enter(struct kvm_vcpu *vcpu,
  *		     struct kvm_cpu_context *host_ctxt);
@@ -60,6 +71,9 @@ SYM_FUNC_START(__guest_enter)
 	// Store the host regs
 	save_callee_saved_regs x1
 
+	// Save the host's sp_el0
+	save_sp_el0	x1, x2
+
 	// Now the host state is stored if we have a pending RAS SError it must
 	// affect the host. If any asynchronous exception is pending we defer
 	// the guest entry. The DSB isn't necessary before v8.2 as any SError
@@ -83,6 +97,9 @@ alternative_else_nop_endif
 	// when this feature is enabled for kernel code.
 	ptrauth_switch_to_guest x29, x0, x1, x2
 
+	// Restore the guest's sp_el0
+	restore_sp_el0 x29, x0
+
 	// Restore guest regs x0-x17
 	ldp	x0, x1,   [x29, #CPU_XREG_OFFSET(0)]
 	ldp	x2, x3,   [x29, #CPU_XREG_OFFSET(2)]
@@ -130,6 +147,9 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// Store the guest regs x18-x29, lr
 	save_callee_saved_regs x1
 
+	// Store the guest's sp_el0
+	save_sp_el0	x1, x2
+
 	get_host_ctxt	x2, x3
 
 	// Macro ptrauth_switch_to_guest format:
@@ -139,6 +159,9 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL)
 	// when this feature is enabled for kernel code.
 	ptrauth_switch_to_host x1, x2, x3, x4, x5
 
+	// Restore the hosts's sp_el0
+	restore_sp_el0 x2, x3
+
 	// Now restore the host regs
 	restore_callee_saved_regs x2
 

arch/arm64/kvm/hyp/hyp-entry.S

@@ -198,7 +198,6 @@ SYM_CODE_END(__hyp_panic)
 .macro invalid_vector	label, target = __hyp_panic
 	.align	2
 SYM_CODE_START(\label)
-\label:
 	b \target
 SYM_CODE_END(\label)
 .endm

arch/arm64/kvm/hyp/sysreg-sr.c

@@ -15,8 +15,9 @@
 /*
  * Non-VHE: Both host and guest must save everything.
  *
- * VHE: Host and guest must save mdscr_el1 and sp_el0 (and the PC and pstate,
- * which are handled as part of the el2 return state) on every switch.
+ * VHE: Host and guest must save mdscr_el1 and sp_el0 (and the PC and
+ * pstate, which are handled as part of the el2 return state) on every
+ * switch (sp_el0 is being dealt with in the assembly code).
  * tpidr_el0 and tpidrro_el0 only need to be switched when going
  * to host userspace or a different VCPU.  EL1 registers only need to be
  * switched when potentially going to run a different VCPU.  The latter two
@@ -26,12 +27,6 @@
 static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt)
 {
 	ctxt->sys_regs[MDSCR_EL1]	= read_sysreg(mdscr_el1);
-
-	/*
-	 * The host arm64 Linux uses sp_el0 to point to 'current' and it must
-	 * therefore be saved/restored on every entry/exit to/from the guest.
-	 */
-	ctxt->gp_regs.regs.sp		= read_sysreg(sp_el0);
 }
 
 static void __hyp_text __sysreg_save_user_state(struct kvm_cpu_context *ctxt)
@@ -99,12 +94,6 @@ NOKPROBE_SYMBOL(sysreg_save_guest_state_vhe);
 static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt)
 {
 	write_sysreg(ctxt->sys_regs[MDSCR_EL1],	  mdscr_el1);
-
-	/*
-	 * The host arm64 Linux uses sp_el0 to point to 'current' and it must
-	 * therefore be saved/restored on every entry/exit to/from the guest.
-	 */
-	write_sysreg(ctxt->gp_regs.regs.sp,	  sp_el0);
 }
 
 static void __hyp_text __sysreg_restore_user_state(struct kvm_cpu_context *ctxt)

arch/arm64/mm/hugetlbpage.c

@@ -230,6 +230,8 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
 		ptep = (pte_t *)pudp;
 	} else if (sz == (CONT_PTE_SIZE)) {
 		pmdp = pmd_alloc(mm, pudp, addr);
+		if (!pmdp)
+			return NULL;
 
 		WARN_ON(addr & (sz - 1));
 		/*

arch/powerpc/kvm/powerpc.c

@@ -521,6 +521,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
 	case KVM_CAP_IMMEDIATE_EXIT:
+	case KVM_CAP_SET_GUEST_DEBUG:
 		r = 1;
 		break;
 	case KVM_CAP_PPC_GUEST_DEBUG_SSTEP:

arch/riscv/Kconfig

@@ -54,7 +54,7 @@ config RISCV
 	select GENERIC_ARCH_TOPOLOGY if SMP
 	select ARCH_HAS_PTE_SPECIAL
 	select ARCH_HAS_MMIOWB
-	select ARCH_HAS_DEBUG_VIRTUAL
+	select ARCH_HAS_DEBUG_VIRTUAL if MMU
 	select HAVE_EBPF_JIT if MMU
 	select EDAC_SUPPORT
 	select ARCH_HAS_GIGANTIC_PAGE
@@ -136,6 +136,7 @@ config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 	def_bool y
 
 config SYS_SUPPORTS_HUGETLBFS
+	depends on MMU
 	def_bool y
 
 config STACKTRACE_SUPPORT

arch/riscv/Kconfig.socs

@@ -11,14 +11,15 @@ config SOC_SIFIVE
 	  This enables support for SiFive SoC platform hardware.
 
 config SOC_VIRT
-       bool "QEMU Virt Machine"
-       select POWER_RESET_SYSCON
-       select POWER_RESET_SYSCON_POWEROFF
-       select GOLDFISH
-       select RTC_DRV_GOLDFISH
-       select SIFIVE_PLIC
-       help
-         This enables support for QEMU Virt Machine.
+	bool "QEMU Virt Machine"
+	select POWER_RESET
+	select POWER_RESET_SYSCON
+	select POWER_RESET_SYSCON_POWEROFF
+	select GOLDFISH
+	select RTC_DRV_GOLDFISH if RTC_CLASS
+	select SIFIVE_PLIC
+	help
+	  This enables support for QEMU Virt Machine.
 
 config SOC_KENDRYTE
 	bool "Kendryte K210 SoC"

arch/riscv/include/asm/csr.h

@@ -51,13 +51,10 @@
 #define CAUSE_IRQ_FLAG		(_AC(1, UL) << (__riscv_xlen - 1))
 
 /* Interrupt causes (minus the high bit) */
-#define IRQ_U_SOFT		0
 #define IRQ_S_SOFT		1
 #define IRQ_M_SOFT		3
-#define IRQ_U_TIMER		4
 #define IRQ_S_TIMER		5
 #define IRQ_M_TIMER		7
-#define IRQ_U_EXT		8
 #define IRQ_S_EXT		9
 #define IRQ_M_EXT		11