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* Re: Looking for architecture papers
From: Segher Boessenkool @ 2018-10-04  8:46 UTC (permalink / raw)
  To: Raz; +Cc: linuxppc-dev
In-Reply-To: <CAPB=Z-pLCkXcsAXD5YWt5pwPzFzJrdZsdDye_bZjE0-ea-Ur6A@mail.gmail.com>

On Thu, Oct 04, 2018 at 10:41:13AM +0300, Raz wrote:
> Frankly, the more I read the more perplexed I get. For example,
> according to BOOK III-S, chapter 3,
> the MSR bits are differ from the ones described in
> arch/powerpc/include/asm/reg.h.
> Bit zero, is LE, but in the book it is 64-bit mode.

LE is bit 63, the least significant bit, value 0x0000000000000001.
SF is bit 0, the most significant bit, value 0x8000000000000000.

Some people wrongly start counting at the end, calling the least
significant bit "bit 0".  That isn't its name.


Segher

^ permalink raw reply

* Re: [PATCH v3 22/33] KVM: PPC: Book3S HV: Handle page fault for a nested guest
From: Paul Mackerras @ 2018-10-04  9:21 UTC (permalink / raw)
  To: David Gibson; +Cc: linuxppc-dev, kvm-ppc, kvm
In-Reply-To: <20181003053913.GP1886@umbus.fritz.box>

On Wed, Oct 03, 2018 at 03:39:13PM +1000, David Gibson wrote:
> On Tue, Oct 02, 2018 at 09:31:21PM +1000, Paul Mackerras wrote:
> > From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> > @@ -367,7 +367,9 @@ struct kvmppc_pte {
> >  	bool may_write		: 1;
> >  	bool may_execute	: 1;
> >  	unsigned long wimg;
> > +	unsigned long rc;
> >  	u8 page_size;		/* MMU_PAGE_xxx */
> > +	u16 page_shift;
> 
> It's a bit ugly that this has both page_size and page_shift, which is
> redundant information AFAICT.  Also, why does page_shift need to be
> u16 - given that 2^255 bytes is much more than our supported address
> space, let alone a plausible page size.

These values are all essentially function outputs, so I don't think
it's ugly to have the same information in different forms.  I actually
don't like using the MMU_PAGE_xxx values, because the information in
the mmu_psize_defs[] array depends on the MMU mode of the host, but
KVM needs to be able to work with guests in both MMU modes.  More
generally I don't think it's a good idea that the KVM <-> guest
interface depends so much on what the host firmware tells us about the
physical machine we're on.  Thus I'm trying to move away from using
MMU_PSIZE_xxx values and mmu_psize_defs[] in KVM code.

I'll change the type to u8.

> > diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
> > index bd06a95..ee6f493 100644
> > --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
> > +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
> > @@ -29,43 +29,16 @@
> >   */
> >  static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 };
> >  
> > -/*
> > - * Used to walk a partition or process table radix tree in guest memory
> > - * Note: We exploit the fact that a partition table and a process
> > - * table have the same layout, a partition-scoped page table and a
> > - * process-scoped page table have the same layout, and the 2nd
> > - * doubleword of a partition table entry has the same layout as
> > - * the PTCR register.
> > - */
> > -int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
> > -				     struct kvmppc_pte *gpte, u64 table,
> > -				     int table_index, u64 *pte_ret_p)
> > +int kvmppc_mmu_walk_radix_tree(struct kvm_vcpu *vcpu, gva_t eaddr,
> > +			       struct kvmppc_pte *gpte, u64 root,
> > +			       u64 *pte_ret_p)
> >  {
> >  	struct kvm *kvm = vcpu->kvm;
> >  	int ret, level, ps;
> > -	unsigned long ptbl, root;
> > -	unsigned long rts, bits, offset;
> > -	unsigned long size, index;
> > -	struct prtb_entry entry;
> > +	unsigned long rts, bits, offset, index;
> >  	u64 pte, base, gpa;
> >  	__be64 rpte;
> >  
> > -	if ((table & PRTS_MASK) > 24)
> > -		return -EINVAL;
> > -	size = 1ul << ((table & PRTS_MASK) + 12);
> > -
> > -	/* Is the table big enough to contain this entry? */
> > -	if ((table_index * sizeof(entry)) >= size)
> > -		return -EINVAL;
> > -
> > -	/* Read the table to find the root of the radix tree */
> > -	ptbl = (table & PRTB_MASK) + (table_index * sizeof(entry));
> > -	ret = kvm_read_guest(kvm, ptbl, &entry, sizeof(entry));
> > -	if (ret)
> > -		return ret;
> > -
> > -	/* Root is stored in the first double word */
> > -	root = be64_to_cpu(entry.prtb0);
> 
> This refactoring somewhat obscures the changes directly relevant to
> the nested guest handling.  Ideally it would be nice to fold some of
> this into the earlier reworkings.

True, but given the rapidly approaching merge window, I'm not inclined
to rework it.

> > +	if (ret) {
> > +		/* We didn't find a pte */
> > +		if (ret == -EINVAL) {
> > +			/* Unsupported mmu config */
> > +			flags |= DSISR_UNSUPP_MMU;
> > +		} else if (ret == -ENOENT) {
> > +			/* No translation found */
> > +			flags |= DSISR_NOHPTE;
> > +		} else if (ret == -EFAULT) {
> > +			/* Couldn't access L1 real address */
> > +			flags |= DSISR_PRTABLE_FAULT;
> > +			vcpu->arch.fault_gpa = fault_addr;
> > +		} else {
> > +			/* Unknown error */
> > +			return ret;
> > +		}
> > +		goto resume_host;
> 
> This is effectively forwarding the fault to L1, yes?  In which case a
> different name might be better than the ambiguous "resume_host".

I'll change it to "forward_to_l1".

Paul.



^ permalink raw reply

* Re: [PATCH v3 29/33] KVM: PPC: Book3S HV: Handle differing endianness for H_ENTER_NESTED
From: Paul Mackerras @ 2018-10-04  9:29 UTC (permalink / raw)
  To: David Gibson; +Cc: linuxppc-dev, kvm-ppc, kvm
In-Reply-To: <20181003061336.GV1886@umbus.fritz.box>

On Wed, Oct 03, 2018 at 04:13:36PM +1000, David Gibson wrote:
> On Tue, Oct 02, 2018 at 09:31:28PM +1000, Paul Mackerras wrote:
> > From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> > 
> > The hcall H_ENTER_NESTED takes as the two parameters the address in
> > L1 guest memory of a hv_regs struct and a pt_regs struct which the
> > L1 guest would like to use to run a L2 guest and in which are returned
> > the exit state of the L2 guest.  For efficiency, these are in the
> > endianness of the L1 guest, rather than being always big-endian as is
> > usually the case for PAPR hypercalls.
> 
> Does that actually make a difference for efficiency?  I thought the
> presence of the byte-reversing loads and stores meant byteswapping was
> basically zero-cost on POWER.

It means that the L1 hypervisor can pass a pointer to the regs struct
in the kvm_vcpu struct rather than having to make a copy, and copy the
values back after the H_ENTER_NESTED.  I'll reword the commit message
to say it's mostly about convenience and to a lesser extent about
performance.

Paul.


^ permalink raw reply

* Re: drivers binding to device node with multiple compatible strings
From: Grant Likely @ 2018-10-04  9:32 UTC (permalink / raw)
  To: leoyang.li
  Cc: open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	Grant Likely, linuxppc-dev, Linux Kernel Mailing List,
	Rob Herring, Frank Rowand, Linux ARM
In-Reply-To: <CADRPPNQam-QUfqDMvu42KS+50VaHfGPhCZj-1jRHQ-Od0fbxuQ@mail.gmail.com>

On Fri, Sep 28, 2018 at 10:01 PM Li Yang <leoyang.li@nxp.com> wrote:
>
> On Fri, Sep 28, 2018 at 3:07 PM Rob Herring <robh+dt@kernel.org> wrote:
> >
> > On Thu, Sep 27, 2018 at 5:25 PM Li Yang <leoyang.li@nxp.com> wrote:
> > >
> > > Hi Rob and Grant,
> > >
> > > Various device tree specs are recommending to include all the
> > > potential compatible strings in the device node, with the order from
> > > most specific to most general.  But it looks like Linux kernel doesn't
> > > provide a way to bind the device to the most specific driver, however,
> > > the first registered compatible driver will be bound.
> > >
> > > As more and more generic drivers are added to the Linux kernel, they
> > > are competing with the more specific vendor drivers and causes problem
> > > when both are built into the kernel.  I'm wondering if there is a
> > > generic solution (or in plan) to make the most specific driver bound
> > > to the device.   Or we have to disable the more general driver or
> > > remove the more general compatible string from the device tree?
> >
> > It's been a known limitation for a long time. However, in practice it
> > doesn't seem to be a common problem. Perhaps folks just remove the
> > less specific compatible from their DT (though that's not ideal). For
> > most modern bindings, there's so many other resources beyond
> > compatible (clocks, resets, pinctrl, etc.) that there are few generic
> > drivers that can work.
> >
> > I guess if we want to fix this, we'd need to have weighted matching in
> > the driver core and unbind drivers when we get a better match. Though
> > it could get messy if the better driver probe fails. Then we've got to
> > rebind to the original driver.
>
> Probably we can populate the platform devices from device tree after
> the device_init phase?  So that all built-in drivers are already
> registered when the devices are created and we can try find the best
> match in one go?  For more specific loadable modules we probably need
> to unbind from the old driver and bind to the new one.  But I agree
> with you that it could be messy.

It's a tradeoff.
>
> >
> > Do you have a specific case where you hit this?
>
> Maybe not a new issue but "snps,dw-pcie" is competing with various
> "fsl,<chip>-pcie" compatibles.  Also a specific PHY
> "ethernet-phy-idAAAA.BBBB" with generic "ethernet-phy-ieee802.3-c45".
>
> Regards,
> Leo

^ permalink raw reply

* Re: drivers binding to device node with multiple compatible strings
From: Grant Likely @ 2018-10-04  9:39 UTC (permalink / raw)
  To: Grant Likely, leoyang.li
  Cc: open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS,
	Frank Rowand, Linux Kernel Mailing List, Rob Herring, nd,
	linuxppc-dev, Linux ARM
In-Reply-To: <CACxGe6u2FQ8r1Ya6-mWoGcs7g2OLMccu68uskZvDLS6ows-hXQ@mail.gmail.com>

On 04/10/2018 10:32, Grant Likely wrote:
> On Fri, Sep 28, 2018 at 10:01 PM Li Yang <leoyang.li@nxp.com> wrote:
>>
>> On Fri, Sep 28, 2018 at 3:07 PM Rob Herring <robh+dt@kernel.org> wrote:
>>>
>>> On Thu, Sep 27, 2018 at 5:25 PM Li Yang <leoyang.li@nxp.com> wrote:
>>>>
>>>> Hi Rob and Grant,
>>>>
>>>> Various device tree specs are recommending to include all the
>>>> potential compatible strings in the device node, with the order from
>>>> most specific to most general.  But it looks like Linux kernel doesn't
>>>> provide a way to bind the device to the most specific driver, however,
>>>> the first registered compatible driver will be bound.
>>>>
>>>> As more and more generic drivers are added to the Linux kernel, they
>>>> are competing with the more specific vendor drivers and causes problem
>>>> when both are built into the kernel.  I'm wondering if there is a
>>>> generic solution (or in plan) to make the most specific driver bound
>>>> to the device.   Or we have to disable the more general driver or
>>>> remove the more general compatible string from the device tree?
>>>
>>> It's been a known limitation for a long time. However, in practice it
>>> doesn't seem to be a common problem. Perhaps folks just remove the
>>> less specific compatible from their DT (though that's not ideal). For
>>> most modern bindings, there's so many other resources beyond
>>> compatible (clocks, resets, pinctrl, etc.) that there are few generic
>>> drivers that can work.
>>>
>>> I guess if we want to fix this, we'd need to have weighted matching in
>>> the driver core and unbind drivers when we get a better match. Though
>>> it could get messy if the better driver probe fails. Then we've got to
>>> rebind to the original driver.
>>
>> Probably we can populate the platform devices from device tree after
>> the device_init phase?  So that all built-in drivers are already
>> registered when the devices are created and we can try find the best
>> match in one go?  For more specific loadable modules we probably need
>> to unbind from the old driver and bind to the new one.  But I agree
>> with you that it could be messy.
> 
> It's a tradeoff.

Oops! Accidentally hit send too early.

It's a tradeoff. If the platform device population is deferred until 
after all drivers are loaded, then there isn't any mechanism to ensure 
some devices get probed early in the init sequence.

As Rob said, while it is a problem in theory, there haven't been a lot 
of actual cases where it is a problem. The solution has been to either 
remove the generic match from the device, or we can blacklist particular 
devices from the generic driver.

g.


>>
>>>
>>> Do you have a specific case where you hit this?
>>
>> Maybe not a new issue but "snps,dw-pcie" is competing with various
>> "fsl,<chip>-pcie" compatibles.  Also a specific PHY
>> "ethernet-phy-idAAAA.BBBB" with generic "ethernet-phy-ieee802.3-c45".
>>
>> Regards,
>> Leo


^ permalink raw reply

* [PATCH v2 -next] powerpc/pseries/memory-hotplug: Fix return value type of find_aa_index
From: YueHaibing @ 2018-10-04  9:41 UTC (permalink / raw)
  To: benh, paulus, mpe, nfont; +Cc: YueHaibing, linuxppc-dev, linux-kernel

'aa_index' is defined as an unsigned value, but find_aa_index
may return -1 when dlpar_clone_property fails. So we use an rc
value to track the validation of finding the aa_index instead
of the 'aa_index' value itself

Fixes: c05a5a40969e ("powerpc/pseries: Dynamic add entires to associativity lookup array")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
---
v2: use 'rc' track the validation of aa_index
---
 arch/powerpc/platforms/pseries/hotplug-memory.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
index 9a15d39..796e68b 100644
--- a/arch/powerpc/platforms/pseries/hotplug-memory.c
+++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -101,13 +101,12 @@ static struct property *dlpar_clone_property(struct property *prop,
 	return new_prop;
 }
 
-static u32 find_aa_index(struct device_node *dr_node,
-			 struct property *ala_prop, const u32 *lmb_assoc)
+static int find_aa_index(struct device_node *dr_node, struct property *ala_prop,
+			 const u32 *lmb_assoc, u32 *aa_index)
 {
 	u32 *assoc_arrays;
-	u32 aa_index;
 	int aa_arrays, aa_array_entries, aa_array_sz;
-	int i, index;
+	int i, index, rc = -1;
 
 	/*
 	 * The ibm,associativity-lookup-arrays property is defined to be
@@ -121,18 +120,18 @@ static u32 find_aa_index(struct device_node *dr_node,
 	aa_array_entries = be32_to_cpu(assoc_arrays[1]);
 	aa_array_sz = aa_array_entries * sizeof(u32);
 
-	aa_index = -1;
 	for (i = 0; i < aa_arrays; i++) {
 		index = (i * aa_array_entries) + 2;
 
 		if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
 			continue;
 
-		aa_index = i;
+		*aa_index = i;
+		rc = 0;
 		break;
 	}
 
-	if (aa_index == -1) {
+	if (rc == -1) {
 		struct property *new_prop;
 		u32 new_prop_size;
 
@@ -157,10 +156,11 @@ static u32 find_aa_index(struct device_node *dr_node,
 		 * number of entries - 1 since we added its associativity
 		 * to the end of the lookup array.
 		 */
-		aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
+		*aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
+		rc = 0;
 	}
 
-	return aa_index;
+	return rc;
 }
 
 static int update_lmb_associativity_index(struct drmem_lmb *lmb)
@@ -169,6 +169,7 @@ static int update_lmb_associativity_index(struct drmem_lmb *lmb)
 	struct property *ala_prop;
 	const u32 *lmb_assoc;
 	u32 aa_index;
+	int rc;
 
 	parent = of_find_node_by_path("/");
 	if (!parent)
@@ -200,11 +201,11 @@ static int update_lmb_associativity_index(struct drmem_lmb *lmb)
 		return -ENODEV;
 	}
 
-	aa_index = find_aa_index(dr_node, ala_prop, lmb_assoc);
+	rc = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);
 
 	dlpar_free_cc_nodes(lmb_node);
 
-	if (aa_index < 0) {
+	if (rc < 0) {
 		pr_err("Could not find LMB associativity\n");
 		return -1;
 	}
-- 
2.7.0



^ permalink raw reply related

* Re: [PATCH v3 33/33] KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualization
From: Paul Mackerras @ 2018-10-04  9:48 UTC (permalink / raw)
  To: David Gibson; +Cc: linuxppc-dev, kvm-ppc, kvm
In-Reply-To: <20181003062144.GY1886@umbus.fritz.box>

On Wed, Oct 03, 2018 at 04:21:44PM +1000, David Gibson wrote:
> On Tue, Oct 02, 2018 at 09:31:32PM +1000, Paul Mackerras wrote:
> > With this, userspace can enable a KVM-HV guest to run nested guests
> > under it.
[snip]
> > +/* If set, guests are allowed to create and control nested guests */
> > +static bool enable_nested = true;
> > +module_param(enable_nested, bool, S_IRUGO | S_IWUSR);
> > +MODULE_PARM_DESC(enable_nested, "Enable nested virtualization (only on POWER9)");
> 
> I'd suggest calling the module parameter just "nested" to match x86.

OK.

> >  /* If set, the threads on each CPU core have to be in the same MMU mode */
> >  static bool no_mixing_hpt_and_radix;
> >  
> > @@ -5188,6 +5193,17 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg)
> >  	return err;
> >  }
> >  
> > +static int kvmhv_enable_nested(struct kvm *kvm, bool enable)
> > +{
> > +	if (!(enable_nested && cpu_has_feature(CPU_FTR_ARCH_300)))
> > +		return -EINVAL;
> 
> Maybe EPERM, rather than EINVAL.  There's nothing invalid about the
> ioctl() parameters - we just can't do what they want.

Just for pedantry's sake, I'll make it EPERM for !enable_nested and
ENODEV for !POWER9. :)

Paul.


^ permalink raw reply

* Re: Looking for architecture papers
From: Gabriel Paubert @ 2018-10-04 10:16 UTC (permalink / raw)
  To: Raz; +Cc: linuxppc-dev
In-Reply-To: <CAPB=Z-pLCkXcsAXD5YWt5pwPzFzJrdZsdDye_bZjE0-ea-Ur6A@mail.gmail.com>

On Thu, Oct 04, 2018 at 10:41:13AM +0300, Raz wrote:
> Frankly, the more I read the more perplexed I get. For example,
> according to BOOK III-S, chapter 3,
> the MSR bits are differ from the ones described in
> arch/powerpc/include/asm/reg.h.
> Bit zero, is LE, but in the book it is 64-bit mode.

Just a problem of bit order definitions: IBM hardware definitions use
big-endian bit ordering, where bit 0 is the most significant bit.

> 
> Would someone be kind to explain what I do not understand?
> 
> Thank you

	Gabriel

^ permalink raw reply

* Re: [PATCH] dma-direct: Fix return value of dma_direct_supported
From: Robin Murphy @ 2018-10-04 11:25 UTC (permalink / raw)
  To: Alexander Duyck, iommu; +Cc: linuxppc-dev, linux-kernel, linux, gregkh
In-Reply-To: <20181003234746.3586.42014.stgit@localhost.localdomain>

On 04/10/18 00:48, Alexander Duyck wrote:
> It appears that in commit 9d7a224b463e ("dma-direct: always allow dma mask
> <= physiscal memory size") the logic of the test was changed from a "<" to
> a ">=" however I don't see any reason for that change. I am assuming that
> there was some additional change planned, specifically I suspect the logic
> was intended to be reversed and possibly used for a return. Since that is
> the case I have gone ahead and done that.

Bah, seems I got hung up on the min_mask code above it and totally 
overlooked that the condition itself got flipped. It probably also can't 
help that it's an int return type, but treated as a bool by callers 
rather than "0 for success" as int tends to imply in isolation.

Anyway, paying a bit more attention this time, I think this looks like 
the right fix - cheers Alex.

Robin.

> This addresses issues I had on my system that prevented me from booting
> with the above mentioned commit applied on an x86_64 system w/ Intel IOMMU.
> 
> Fixes: 9d7a224b463e ("dma-direct: always allow dma mask <= physiscal memory size")
> Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
> ---
>   kernel/dma/direct.c |    4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
> index 5a0806b5351b..65872f6c2e93 100644
> --- a/kernel/dma/direct.c
> +++ b/kernel/dma/direct.c
> @@ -301,9 +301,7 @@ int dma_direct_supported(struct device *dev, u64 mask)
>   
>   	min_mask = min_t(u64, min_mask, (max_pfn - 1) << PAGE_SHIFT);
>   
> -	if (mask >= phys_to_dma(dev, min_mask))
> -		return 0;
> -	return 1;
> +	return mask >= phys_to_dma(dev, min_mask);
>   }
>   
>   int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
> 
> _______________________________________________
> iommu mailing list
> iommu@lists.linux-foundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/iommu
> 

^ permalink raw reply

* [PATCH v4 04/32] KVM: PPC: Book3S HV: Move interrupt delivery on guest entry to C code
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This is based on a patch by Suraj Jitindar Singh.

This moves the code in book3s_hv_rmhandlers.S that generates an
external, decrementer or privileged doorbell interrupt just before
entering the guest to C code in book3s_hv_builtin.c.  This is to
make future maintenance and modification easier.  The algorithm
expressed in the C code is almost identical to the previous
algorithm.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/kvm_ppc.h      |  1 +
 arch/powerpc/kvm/book3s_hv.c            |  3 +-
 arch/powerpc/kvm/book3s_hv_builtin.c    | 48 ++++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 70 ++++++++-------------------------
 4 files changed, 67 insertions(+), 55 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index e991821..83d61b8 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -652,6 +652,7 @@ int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
                     unsigned long mfrr);
 int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr);
 int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr);
+void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu);
 
 /*
  * Host-side operations we want to set up while running in real
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 3e3a715..49a686c 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -730,8 +730,7 @@ static bool kvmppc_doorbell_pending(struct kvm_vcpu *vcpu)
 	/*
 	 * Ensure that the read of vcore->dpdes comes after the read
 	 * of vcpu->doorbell_request.  This barrier matches the
-	 * lwsync in book3s_hv_rmhandlers.S just before the
-	 * fast_guest_return label.
+	 * smb_wmb() in kvmppc_guest_entry_inject().
 	 */
 	smp_rmb();
 	vc = vcpu->arch.vcore;
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index fc6bb96..ccfea5b 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -729,3 +729,51 @@ void kvmhv_p9_restore_lpcr(struct kvm_split_mode *sip)
 	smp_mb();
 	local_paca->kvm_hstate.kvm_split_mode = NULL;
 }
+
+/*
+ * Is there a PRIV_DOORBELL pending for the guest (on POWER9)?
+ * Can we inject a Decrementer or a External interrupt?
+ */
+void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu)
+{
+	int ext;
+	unsigned long vec = 0;
+	unsigned long lpcr;
+
+	/* Insert EXTERNAL bit into LPCR at the MER bit position */
+	ext = (vcpu->arch.pending_exceptions >> BOOK3S_IRQPRIO_EXTERNAL) & 1;
+	lpcr = mfspr(SPRN_LPCR);
+	lpcr |= ext << LPCR_MER_SH;
+	mtspr(SPRN_LPCR, lpcr);
+	isync();
+
+	if (vcpu->arch.shregs.msr & MSR_EE) {
+		if (ext) {
+			vec = BOOK3S_INTERRUPT_EXTERNAL;
+		} else {
+			long int dec = mfspr(SPRN_DEC);
+			if (!(lpcr & LPCR_LD))
+				dec = (int) dec;
+			if (dec < 0)
+				vec = BOOK3S_INTERRUPT_DECREMENTER;
+		}
+	}
+	if (vec) {
+		unsigned long msr, old_msr = vcpu->arch.shregs.msr;
+
+		kvmppc_set_srr0(vcpu, kvmppc_get_pc(vcpu));
+		kvmppc_set_srr1(vcpu, old_msr);
+		kvmppc_set_pc(vcpu, vec);
+		msr = vcpu->arch.intr_msr;
+		if (MSR_TM_ACTIVE(old_msr))
+			msr |= MSR_TS_S;
+		vcpu->arch.shregs.msr = msr;
+	}
+
+	if (vcpu->arch.doorbell_request) {
+		mtspr(SPRN_DPDES, 1);
+		vcpu->arch.vcore->dpdes = 1;
+		smp_wmb();
+		vcpu->arch.doorbell_request = 0;
+	}
+}
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 77960e6..6752da1 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1101,13 +1101,20 @@ no_xive:
 #endif /* CONFIG_KVM_XICS */
 
 deliver_guest_interrupt:
-	ld	r6, VCPU_CTR(r4)
-	ld	r7, VCPU_XER(r4)
-
-	mtctr	r6
-	mtxer	r7
-
 kvmppc_cede_reentry:		/* r4 = vcpu, r13 = paca */
+	/* Check if we can deliver an external or decrementer interrupt now */
+	ld	r0, VCPU_PENDING_EXC(r4)
+BEGIN_FTR_SECTION
+	/* On POWER9, also check for emulated doorbell interrupt */
+	lbz	r3, VCPU_DBELL_REQ(r4)
+	or	r0, r0, r3
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
+	cmpdi	r0, 0
+	beq	71f
+	mr	r3, r4
+	bl	kvmppc_guest_entry_inject_int
+	ld	r4, HSTATE_KVM_VCPU(r13)
+71:
 	ld	r10, VCPU_PC(r4)
 	ld	r11, VCPU_MSR(r4)
 	ld	r6, VCPU_SRR0(r4)
@@ -1120,53 +1127,10 @@ kvmppc_cede_reentry:		/* r4 = vcpu, r13 = paca */
 	rotldi	r11, r11, 1 + MSR_HV_LG
 	ori	r11, r11, MSR_ME
 
-	/* Check if we can deliver an external or decrementer interrupt now */
-	ld	r0, VCPU_PENDING_EXC(r4)
-	rldicl	r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL, 63
-	cmpdi	cr1, r0, 0
-	andi.	r8, r11, MSR_EE
-	mfspr	r8, SPRN_LPCR
-	/* Insert EXTERNAL bit into LPCR at the MER bit position */
-	rldimi	r8, r0, LPCR_MER_SH, 63 - LPCR_MER_SH
-	mtspr	SPRN_LPCR, r8
-	isync
-	beq	5f
-	li	r0, BOOK3S_INTERRUPT_EXTERNAL
-	bne	cr1, 12f
-	mfspr	r0, SPRN_DEC
-BEGIN_FTR_SECTION
-	/* On POWER9 check whether the guest has large decrementer enabled */
-	andis.	r8, r8, LPCR_LD@h
-	bne	15f
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
-	extsw	r0, r0
-15:	cmpdi	r0, 0
-	li	r0, BOOK3S_INTERRUPT_DECREMENTER
-	bge	5f
-
-12:	mtspr	SPRN_SRR0, r10
-	mr	r10,r0
-	mtspr	SPRN_SRR1, r11
-	mr	r9, r4
-	bl	kvmppc_msr_interrupt
-5:
-BEGIN_FTR_SECTION
-	b	fast_guest_return
-END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
-	/* On POWER9, check for pending doorbell requests */
-	lbz	r0, VCPU_DBELL_REQ(r4)
-	cmpwi	r0, 0
-	beq	fast_guest_return
-	ld	r5, HSTATE_KVM_VCORE(r13)
-	/* Set DPDES register so the CPU will take a doorbell interrupt */
-	li	r0, 1
-	mtspr	SPRN_DPDES, r0
-	std	r0, VCORE_DPDES(r5)
-	/* Make sure other cpus see vcore->dpdes set before dbell req clear */
-	lwsync
-	/* Clear the pending doorbell request */
-	li	r0, 0
-	stb	r0, VCPU_DBELL_REQ(r4)
+	ld	r6, VCPU_CTR(r4)
+	ld	r7, VCPU_XER(r4)
+	mtctr	r6
+	mtxer	r7
 
 /*
  * Required state:
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 02/32] KVM: PPC: Book3S: Simplify external interrupt handling
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

Currently we use two bits in the vcpu pending_exceptions bitmap to
indicate that an external interrupt is pending for the guest, one
for "one-shot" interrupts that are cleared when delivered, and one
for interrupts that persist until cleared by an explicit action of
the OS (e.g. an acknowledge to an interrupt controller).  The
BOOK3S_IRQPRIO_EXTERNAL bit is used for one-shot interrupt requests
and BOOK3S_IRQPRIO_EXTERNAL_LEVEL is used for persisting interrupts.

In practice BOOK3S_IRQPRIO_EXTERNAL never gets used, because our
Book3S platforms generally, and pseries in particular, expect
external interrupt requests to persist until they are acknowledged
at the interrupt controller.  That combined with the confusion
introduced by having two bits for what is essentially the same thing
makes it attractive to simplify things by only using one bit.  This
patch does that.

With this patch there is only BOOK3S_IRQPRIO_EXTERNAL, and by default
it has the semantics of a persisting interrupt.  In order to avoid
breaking the ABI, we introduce a new "external_oneshot" flag which
preserves the behaviour of the KVM_INTERRUPT ioctl with the
KVM_INTERRUPT_SET argument.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/kvm_asm.h             |  4 +--
 arch/powerpc/include/asm/kvm_host.h            |  1 +
 arch/powerpc/kvm/book3s.c                      | 43 ++++++++++++++++++++------
 arch/powerpc/kvm/book3s_hv_rm_xics.c           |  5 ++-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S        |  4 +--
 arch/powerpc/kvm/book3s_pr.c                   |  1 -
 arch/powerpc/kvm/book3s_xics.c                 | 11 +++----
 arch/powerpc/kvm/book3s_xive_template.c        |  2 +-
 arch/powerpc/kvm/trace_book3s.h                |  1 -
 tools/perf/arch/powerpc/util/book3s_hv_exits.h |  1 -
 10 files changed, 44 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_asm.h b/arch/powerpc/include/asm/kvm_asm.h
index a790d5c..1f32191 100644
--- a/arch/powerpc/include/asm/kvm_asm.h
+++ b/arch/powerpc/include/asm/kvm_asm.h
@@ -84,7 +84,6 @@
 #define BOOK3S_INTERRUPT_INST_STORAGE	0x400
 #define BOOK3S_INTERRUPT_INST_SEGMENT	0x480
 #define BOOK3S_INTERRUPT_EXTERNAL	0x500
-#define BOOK3S_INTERRUPT_EXTERNAL_LEVEL	0x501
 #define BOOK3S_INTERRUPT_EXTERNAL_HV	0x502
 #define BOOK3S_INTERRUPT_ALIGNMENT	0x600
 #define BOOK3S_INTERRUPT_PROGRAM	0x700
@@ -134,8 +133,7 @@
 #define BOOK3S_IRQPRIO_EXTERNAL			14
 #define BOOK3S_IRQPRIO_DECREMENTER		15
 #define BOOK3S_IRQPRIO_PERFORMANCE_MONITOR	16
-#define BOOK3S_IRQPRIO_EXTERNAL_LEVEL		17
-#define BOOK3S_IRQPRIO_MAX			18
+#define BOOK3S_IRQPRIO_MAX			17
 
 #define BOOK3S_HFLAG_DCBZ32			0x1
 #define BOOK3S_HFLAG_SLB			0x2
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 906bcbdf..3cd0b9f 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -707,6 +707,7 @@ struct kvm_vcpu_arch {
 	u8 hcall_needed;
 	u8 epr_flags; /* KVMPPC_EPR_xxx */
 	u8 epr_needed;
+	u8 external_oneshot;	/* clear external irq after delivery */
 
 	u32 cpr0_cfgaddr; /* holds the last set cpr0_cfgaddr */
 
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 87348e4..66a5521 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -150,7 +150,6 @@ static int kvmppc_book3s_vec2irqprio(unsigned int vec)
 	case 0x400: prio = BOOK3S_IRQPRIO_INST_STORAGE;		break;
 	case 0x480: prio = BOOK3S_IRQPRIO_INST_SEGMENT;		break;
 	case 0x500: prio = BOOK3S_IRQPRIO_EXTERNAL;		break;
-	case 0x501: prio = BOOK3S_IRQPRIO_EXTERNAL_LEVEL;	break;
 	case 0x600: prio = BOOK3S_IRQPRIO_ALIGNMENT;		break;
 	case 0x700: prio = BOOK3S_IRQPRIO_PROGRAM;		break;
 	case 0x800: prio = BOOK3S_IRQPRIO_FP_UNAVAIL;		break;
@@ -236,18 +235,35 @@ EXPORT_SYMBOL_GPL(kvmppc_core_dequeue_dec);
 void kvmppc_core_queue_external(struct kvm_vcpu *vcpu,
                                 struct kvm_interrupt *irq)
 {
-	unsigned int vec = BOOK3S_INTERRUPT_EXTERNAL;
-
-	if (irq->irq == KVM_INTERRUPT_SET_LEVEL)
-		vec = BOOK3S_INTERRUPT_EXTERNAL_LEVEL;
+	/*
+	 * This case (KVM_INTERRUPT_SET) should never actually arise for
+	 * a pseries guest (because pseries guests expect their interrupt
+	 * controllers to continue asserting an external interrupt request
+	 * until it is acknowledged at the interrupt controller), but is
+	 * included to avoid ABI breakage and potentially for other
+	 * sorts of guest.
+	 *
+	 * There is a subtlety here: HV KVM does not test the
+	 * external_oneshot flag in the code that synthesizes
+	 * external interrupts for the guest just before entering
+	 * the guest.  That is OK even if userspace did do a
+	 * KVM_INTERRUPT_SET on a pseries guest vcpu, because the
+	 * caller (kvm_vcpu_ioctl_interrupt) does a kvm_vcpu_kick()
+	 * which ends up doing a smp_send_reschedule(), which will
+	 * pull the guest all the way out to the host, meaning that
+	 * we will call kvmppc_core_prepare_to_enter() before entering
+	 * the guest again, and that will handle the external_oneshot
+	 * flag correctly.
+	 */
+	if (irq->irq == KVM_INTERRUPT_SET)
+		vcpu->arch.external_oneshot = 1;
 
-	kvmppc_book3s_queue_irqprio(vcpu, vec);
+	kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_EXTERNAL);
 }
 
 void kvmppc_core_dequeue_external(struct kvm_vcpu *vcpu)
 {
 	kvmppc_book3s_dequeue_irqprio(vcpu, BOOK3S_INTERRUPT_EXTERNAL);
-	kvmppc_book3s_dequeue_irqprio(vcpu, BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
 }
 
 void kvmppc_core_queue_data_storage(struct kvm_vcpu *vcpu, ulong dar,
@@ -278,7 +294,6 @@ static int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu,
 		vec = BOOK3S_INTERRUPT_DECREMENTER;
 		break;
 	case BOOK3S_IRQPRIO_EXTERNAL:
-	case BOOK3S_IRQPRIO_EXTERNAL_LEVEL:
 		deliver = (kvmppc_get_msr(vcpu) & MSR_EE) && !crit;
 		vec = BOOK3S_INTERRUPT_EXTERNAL;
 		break;
@@ -352,8 +367,16 @@ static bool clear_irqprio(struct kvm_vcpu *vcpu, unsigned int priority)
 		case BOOK3S_IRQPRIO_DECREMENTER:
 			/* DEC interrupts get cleared by mtdec */
 			return false;
-		case BOOK3S_IRQPRIO_EXTERNAL_LEVEL:
-			/* External interrupts get cleared by userspace */
+		case BOOK3S_IRQPRIO_EXTERNAL:
+			/*
+			 * External interrupts get cleared by userspace
+			 * except when set by the KVM_INTERRUPT ioctl with
+			 * KVM_INTERRUPT_SET (not KVM_INTERRUPT_SET_LEVEL).
+			 */
+			if (vcpu->arch.external_oneshot) {
+				vcpu->arch.external_oneshot = 0;
+				return true;
+			}
 			return false;
 	}
 
diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c
index 758d1d2..8b9f356 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_xics.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c
@@ -136,7 +136,7 @@ static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu,
 
 	/* Mark the target VCPU as having an interrupt pending */
 	vcpu->stat.queue_intr++;
-	set_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL, &vcpu->arch.pending_exceptions);
+	set_bit(BOOK3S_IRQPRIO_EXTERNAL, &vcpu->arch.pending_exceptions);
 
 	/* Kick self ? Just set MER and return */
 	if (vcpu == this_vcpu) {
@@ -170,8 +170,7 @@ static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu,
 static void icp_rm_clr_vcpu_irq(struct kvm_vcpu *vcpu)
 {
 	/* Note: Only called on self ! */
-	clear_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL,
-		  &vcpu->arch.pending_exceptions);
+	clear_bit(BOOK3S_IRQPRIO_EXTERNAL, &vcpu->arch.pending_exceptions);
 	mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~LPCR_MER);
 }
 
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 1d14046..77960e6 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1122,11 +1122,11 @@ kvmppc_cede_reentry:		/* r4 = vcpu, r13 = paca */
 
 	/* Check if we can deliver an external or decrementer interrupt now */
 	ld	r0, VCPU_PENDING_EXC(r4)
-	rldicl	r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL_LEVEL, 63
+	rldicl	r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL, 63
 	cmpdi	cr1, r0, 0
 	andi.	r8, r11, MSR_EE
 	mfspr	r8, SPRN_LPCR
-	/* Insert EXTERNAL_LEVEL bit into LPCR at the MER bit position */
+	/* Insert EXTERNAL bit into LPCR at the MER bit position */
 	rldimi	r8, r0, LPCR_MER_SH, 63 - LPCR_MER_SH
 	mtspr	SPRN_LPCR, r8
 	isync
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index 614ebb4..059683e4 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -1246,7 +1246,6 @@ int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		r = RESUME_GUEST;
 		break;
 	case BOOK3S_INTERRUPT_EXTERNAL:
-	case BOOK3S_INTERRUPT_EXTERNAL_LEVEL:
 	case BOOK3S_INTERRUPT_EXTERNAL_HV:
 	case BOOK3S_INTERRUPT_H_VIRT:
 		vcpu->stat.ext_intr_exits++;
diff --git a/arch/powerpc/kvm/book3s_xics.c b/arch/powerpc/kvm/book3s_xics.c
index b8356cd..d9ba1b0 100644
--- a/arch/powerpc/kvm/book3s_xics.c
+++ b/arch/powerpc/kvm/book3s_xics.c
@@ -310,7 +310,7 @@ static inline bool icp_try_update(struct kvmppc_icp *icp,
 	 */
 	if (new.out_ee) {
 		kvmppc_book3s_queue_irqprio(icp->vcpu,
-					    BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+					    BOOK3S_INTERRUPT_EXTERNAL);
 		if (!change_self)
 			kvmppc_fast_vcpu_kick(icp->vcpu);
 	}
@@ -593,8 +593,7 @@ static noinline unsigned long kvmppc_h_xirr(struct kvm_vcpu *vcpu)
 	u32 xirr;
 
 	/* First, remove EE from the processor */
-	kvmppc_book3s_dequeue_irqprio(icp->vcpu,
-				      BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+	kvmppc_book3s_dequeue_irqprio(icp->vcpu, BOOK3S_INTERRUPT_EXTERNAL);
 
 	/*
 	 * ICP State: Accept_Interrupt
@@ -754,8 +753,7 @@ static noinline void kvmppc_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr)
 	 * We can remove EE from the current processor, the update
 	 * transaction will set it again if needed
 	 */
-	kvmppc_book3s_dequeue_irqprio(icp->vcpu,
-				      BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+	kvmppc_book3s_dequeue_irqprio(icp->vcpu, BOOK3S_INTERRUPT_EXTERNAL);
 
 	do {
 		old_state = new_state = READ_ONCE(icp->state);
@@ -1167,8 +1165,7 @@ int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval)
 	 * Deassert the CPU interrupt request.
 	 * icp_try_update will reassert it if necessary.
 	 */
-	kvmppc_book3s_dequeue_irqprio(icp->vcpu,
-				      BOOK3S_INTERRUPT_EXTERNAL_LEVEL);
+	kvmppc_book3s_dequeue_irqprio(icp->vcpu, BOOK3S_INTERRUPT_EXTERNAL);
 
 	/*
 	 * Note that if we displace an interrupt from old_state.xisr,
diff --git a/arch/powerpc/kvm/book3s_xive_template.c b/arch/powerpc/kvm/book3s_xive_template.c
index 4171ede..203ea65 100644
--- a/arch/powerpc/kvm/book3s_xive_template.c
+++ b/arch/powerpc/kvm/book3s_xive_template.c
@@ -285,7 +285,7 @@ X_STATIC unsigned long GLUE(X_PFX,h_xirr)(struct kvm_vcpu *vcpu)
 	 * set by pull or an escalation interrupts).
 	 */
 	if (test_bit(BOOK3S_IRQPRIO_EXTERNAL, &vcpu->arch.pending_exceptions))
-		clear_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL,
+		clear_bit(BOOK3S_IRQPRIO_EXTERNAL,
 			  &vcpu->arch.pending_exceptions);
 
 	pr_devel(" new pending=0x%02x hw_cppr=%d cppr=%d\n",
diff --git a/arch/powerpc/kvm/trace_book3s.h b/arch/powerpc/kvm/trace_book3s.h
index f3b2375..372a82f 100644
--- a/arch/powerpc/kvm/trace_book3s.h
+++ b/arch/powerpc/kvm/trace_book3s.h
@@ -14,7 +14,6 @@
 	{0x400, "INST_STORAGE"}, \
 	{0x480, "INST_SEGMENT"}, \
 	{0x500, "EXTERNAL"}, \
-	{0x501, "EXTERNAL_LEVEL"}, \
 	{0x502, "EXTERNAL_HV"}, \
 	{0x600, "ALIGNMENT"}, \
 	{0x700, "PROGRAM"}, \
diff --git a/tools/perf/arch/powerpc/util/book3s_hv_exits.h b/tools/perf/arch/powerpc/util/book3s_hv_exits.h
index 853b95d1..2011376 100644
--- a/tools/perf/arch/powerpc/util/book3s_hv_exits.h
+++ b/tools/perf/arch/powerpc/util/book3s_hv_exits.h
@@ -15,7 +15,6 @@
 	{0x400, "INST_STORAGE"}, \
 	{0x480, "INST_SEGMENT"}, \
 	{0x500, "EXTERNAL"}, \
-	{0x501, "EXTERNAL_LEVEL"}, \
 	{0x502, "EXTERNAL_HV"}, \
 	{0x600, "ALIGNMENT"}, \
 	{0x700, "PROGRAM"}, \
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 03/32] KVM: PPC: Book3S HV: Remove left-over code in XICS-on-XIVE emulation
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This removes code that clears the external interrupt pending bit in
the pending_exceptions bitmap.  This is left over from an earlier
iteration of the code where this bit was set when an escalation
interrupt arrived in order to wake the vcpu from cede.  Currently
we set the vcpu->arch.irq_pending flag instead for this purpose.
Therefore there is no need to do anything with the pending_exceptions
bitmap.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kvm/book3s_xive_template.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_xive_template.c b/arch/powerpc/kvm/book3s_xive_template.c
index 203ea65..033363d 100644
--- a/arch/powerpc/kvm/book3s_xive_template.c
+++ b/arch/powerpc/kvm/book3s_xive_template.c
@@ -280,14 +280,6 @@ X_STATIC unsigned long GLUE(X_PFX,h_xirr)(struct kvm_vcpu *vcpu)
 	/* First collect pending bits from HW */
 	GLUE(X_PFX,ack_pending)(xc);
 
-	/*
-	 * Cleanup the old-style bits if needed (they may have been
-	 * set by pull or an escalation interrupts).
-	 */
-	if (test_bit(BOOK3S_IRQPRIO_EXTERNAL, &vcpu->arch.pending_exceptions))
-		clear_bit(BOOK3S_IRQPRIO_EXTERNAL,
-			  &vcpu->arch.pending_exceptions);
-
 	pr_devel(" new pending=0x%02x hw_cppr=%d cppr=%d\n",
 		 xc->pending, xc->hw_cppr, xc->cppr);
 
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 01/32] powerpc: Turn off CPU_FTR_P9_TM_HV_ASSIST in non-hypervisor mode
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

When doing nested virtualization, it is only necessary to do the
transactional memory hypervisor assist at level 0, that is, when
we are in hypervisor mode.  Nested hypervisors can just use the TM
facilities as architected.  Therefore we should clear the
CPU_FTR_P9_TM_HV_ASSIST bit when we are not in hypervisor mode,
along with the CPU_FTR_HVMODE bit.

Doing this will not change anything at this stage because the only
code that tests CPU_FTR_P9_TM_HV_ASSIST is in HV KVM, which currently
can only be used when when CPU_FTR_HVMODE is set.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kernel/cpu_setup_power.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
index 458b928..c317080 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S
@@ -147,8 +147,8 @@ __init_hvmode_206:
 	rldicl.	r0,r3,4,63
 	bnelr
 	ld	r5,CPU_SPEC_FEATURES(r4)
-	LOAD_REG_IMMEDIATE(r6,CPU_FTR_HVMODE)
-	xor	r5,r5,r6
+	LOAD_REG_IMMEDIATE(r6,CPU_FTR_HVMODE | CPU_FTR_P9_TM_HV_ASSIST)
+	andc	r5,r5,r6
 	std	r5,CPU_SPEC_FEATURES(r4)
 	blr
 
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 00/32] KVM: PPC: Book3S HV: Nested HV virtualization
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson

This patch series implements nested virtualization in the KVM-HV
module for radix guests on POWER9 systems.  Unlike PR KVM, nested
guests are able to run in supervisor mode, meaning that performance is
much better than with PR KVM, and is very close to the performance of
a non-nested guests for most things.

The way this works is that each nested guest is also a guest of the
real hypervisor, also known as the level 0 or L0 hypervisor, which
runs in the CPU's hypervisor mode.  Its guests are at level 1, and
when a L1 system wants to run a nested guest, it performs hypercalls
to L0 to set up a virtual partition table in its (L1's) memory and to
enter the L2 guest.  The L0 hypervisor maintains a shadow
partition-scoped page table for the L2 guest and demand-faults entries
into it by translating the L1 real addresses in the partition-scoped
page table in L1 memory into L0 real addresses and puts them in the
shadow partition-scoped page table for L2.

Essentially what this is doing is providing L1 with the ability to do
(some) hypervisor functions using paravirtualization; optionally,
TLB invalidations can be done through emulation of the tlbie
instruction rather than a hypercall.

Along the way, this implements a new guest entry/exit path for radix
guests on POWER9 systems which is written almost entirely in C and
does not do any of the inter-thread coordination that the existing
entry/exit path does.  It is only used for radix guests and when
indep_threads_mode=Y (the default).

The limitations of this scheme are:

- Host and all nested hypervisors and their guests must be in radix
  mode.

- Nested hypervisors cannot use indep_threads_mode=N.

- If the host (i.e. the L0 hypervisor) has indep_threads_mode=N then
  only one nested vcpu can be run on any core at any given time; the
  secondary threads will do nothing.

- A nested hypervisor can't use a smaller page size than the base page
  size of the hypervisor(s) above it.

- A nested hypervisor is limited to having at most 1023 guests below
  it, each of which can have at most NR_CPUS virtual CPUs (and the
  virtual CPU ids have to be < NR_CPUS as well).

This patch series is against my kvm-ppc-fixes branch.

Changes in this version since version 3:

- Removed instruction emulation code.

- Validate parameter to H_SET_PARTITION_TABLE hcall.

- Minor changes in response to review comments.

Paul.

 Documentation/virtual/kvm/api.txt                  |   15 +
 arch/powerpc/include/asm/asm-prototypes.h          |   21 +
 arch/powerpc/include/asm/book3s/64/mmu-hash.h      |   12 +
 .../powerpc/include/asm/book3s/64/tlbflush-radix.h |    1 +
 arch/powerpc/include/asm/hvcall.h                  |   41 +
 arch/powerpc/include/asm/kvm_asm.h                 |    4 +-
 arch/powerpc/include/asm/kvm_book3s.h              |   45 +-
 arch/powerpc/include/asm/kvm_book3s_64.h           |  119 +-
 arch/powerpc/include/asm/kvm_book3s_asm.h          |    3 +
 arch/powerpc/include/asm/kvm_booke.h               |    4 +-
 arch/powerpc/include/asm/kvm_host.h                |   16 +-
 arch/powerpc/include/asm/kvm_ppc.h                 |    4 +
 arch/powerpc/include/asm/ppc-opcode.h              |    1 +
 arch/powerpc/include/asm/reg.h                     |    2 +
 arch/powerpc/include/uapi/asm/kvm.h                |    1 +
 arch/powerpc/kernel/asm-offsets.c                  |    5 +-
 arch/powerpc/kernel/cpu_setup_power.S              |    4 +-
 arch/powerpc/kvm/Makefile                          |    3 +-
 arch/powerpc/kvm/book3s.c                          |   43 +-
 arch/powerpc/kvm/book3s_64_mmu_hv.c                |    7 +-
 arch/powerpc/kvm/book3s_64_mmu_radix.c             |  718 ++++++++---
 arch/powerpc/kvm/book3s_emulate.c                  |   13 +-
 arch/powerpc/kvm/book3s_hv.c                       |  842 ++++++++++++-
 arch/powerpc/kvm/book3s_hv_builtin.c               |   92 +-
 arch/powerpc/kvm/book3s_hv_interrupts.S            |   95 +-
 arch/powerpc/kvm/book3s_hv_nested.c                | 1280 ++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv_ras.c                   |   10 +
 arch/powerpc/kvm/book3s_hv_rm_xics.c               |   13 +-
 arch/powerpc/kvm/book3s_hv_rmhandlers.S            |  809 +++++++------
 arch/powerpc/kvm/book3s_hv_tm.c                    |    6 +-
 arch/powerpc/kvm/book3s_hv_tm_builtin.c            |    5 +-
 arch/powerpc/kvm/book3s_pr.c                       |    5 +-
 arch/powerpc/kvm/book3s_xics.c                     |   14 +-
 arch/powerpc/kvm/book3s_xive.c                     |   63 +
 arch/powerpc/kvm/book3s_xive_template.c            |    8 -
 arch/powerpc/kvm/bookehv_interrupts.S              |    8 +-
 arch/powerpc/kvm/emulate_loadstore.c               |    1 -
 arch/powerpc/kvm/powerpc.c                         |   12 +
 arch/powerpc/kvm/tm.S                              |  250 ++--
 arch/powerpc/kvm/trace_book3s.h                    |    1 -
 arch/powerpc/mm/tlb-radix.c                        |    9 +
 include/uapi/linux/kvm.h                           |    1 +
 tools/perf/arch/powerpc/util/book3s_hv_exits.h     |    1 -
 43 files changed, 3772 insertions(+), 835 deletions(-)

^ permalink raw reply

* [PATCH v4 05/32] KVM: PPC: Book3S HV: Extract PMU save/restore operations as C-callable functions
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This pulls out the assembler code that is responsible for saving and
restoring the PMU state for the host and guest into separate functions
so they can be used from an alternate entry path.  The calling
convention is made compatible with C.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/asm-prototypes.h |   5 +
 arch/powerpc/kvm/book3s_hv_interrupts.S   |  95 ++++----
 arch/powerpc/kvm/book3s_hv_rmhandlers.S   | 363 ++++++++++++++++--------------
 3 files changed, 253 insertions(+), 210 deletions(-)

diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 1f4691c..024e8fc 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -150,4 +150,9 @@ extern s32 patch__memset_nocache, patch__memcpy_nocache;
 
 extern long flush_count_cache;
 
+void kvmhv_save_host_pmu(void);
+void kvmhv_load_host_pmu(void);
+void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use);
+void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu);
+
 #endif /* _ASM_POWERPC_ASM_PROTOTYPES_H */
diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S
index 666b91c..a6d1001 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupts.S
+++ b/arch/powerpc/kvm/book3s_hv_interrupts.S
@@ -64,52 +64,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 
 	/* Save host PMU registers */
-BEGIN_FTR_SECTION
-	/* Work around P8 PMAE bug */
-	li	r3, -1
-	clrrdi	r3, r3, 10
-	mfspr	r8, SPRN_MMCR2
-	mtspr	SPRN_MMCR2, r3		/* freeze all counters using MMCR2 */
-	isync
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-	li	r3, 1
-	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
-	mfspr	r7, SPRN_MMCR0		/* save MMCR0 */
-	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable interrupts */
-	mfspr	r6, SPRN_MMCRA
-	/* Clear MMCRA in order to disable SDAR updates */
-	li	r5, 0
-	mtspr	SPRN_MMCRA, r5
-	isync
-	lbz	r5, PACA_PMCINUSE(r13)	/* is the host using the PMU? */
-	cmpwi	r5, 0
-	beq	31f			/* skip if not */
-	mfspr	r5, SPRN_MMCR1
-	mfspr	r9, SPRN_SIAR
-	mfspr	r10, SPRN_SDAR
-	std	r7, HSTATE_MMCR0(r13)
-	std	r5, HSTATE_MMCR1(r13)
-	std	r6, HSTATE_MMCRA(r13)
-	std	r9, HSTATE_SIAR(r13)
-	std	r10, HSTATE_SDAR(r13)
-BEGIN_FTR_SECTION
-	mfspr	r9, SPRN_SIER
-	std	r8, HSTATE_MMCR2(r13)
-	std	r9, HSTATE_SIER(r13)
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-	mfspr	r3, SPRN_PMC1
-	mfspr	r5, SPRN_PMC2
-	mfspr	r6, SPRN_PMC3
-	mfspr	r7, SPRN_PMC4
-	mfspr	r8, SPRN_PMC5
-	mfspr	r9, SPRN_PMC6
-	stw	r3, HSTATE_PMC1(r13)
-	stw	r5, HSTATE_PMC2(r13)
-	stw	r6, HSTATE_PMC3(r13)
-	stw	r7, HSTATE_PMC4(r13)
-	stw	r8, HSTATE_PMC5(r13)
-	stw	r9, HSTATE_PMC6(r13)
-31:
+	bl	kvmhv_save_host_pmu
 
 	/*
 	 * Put whatever is in the decrementer into the
@@ -161,3 +116,51 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	ld	r0, PPC_LR_STKOFF(r1)
 	mtlr	r0
 	blr
+
+_GLOBAL(kvmhv_save_host_pmu)
+BEGIN_FTR_SECTION
+	/* Work around P8 PMAE bug */
+	li	r3, -1
+	clrrdi	r3, r3, 10
+	mfspr	r8, SPRN_MMCR2
+	mtspr	SPRN_MMCR2, r3		/* freeze all counters using MMCR2 */
+	isync
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+	li	r3, 1
+	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
+	mfspr	r7, SPRN_MMCR0		/* save MMCR0 */
+	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable interrupts */
+	mfspr	r6, SPRN_MMCRA
+	/* Clear MMCRA in order to disable SDAR updates */
+	li	r5, 0
+	mtspr	SPRN_MMCRA, r5
+	isync
+	lbz	r5, PACA_PMCINUSE(r13)	/* is the host using the PMU? */
+	cmpwi	r5, 0
+	beq	31f			/* skip if not */
+	mfspr	r5, SPRN_MMCR1
+	mfspr	r9, SPRN_SIAR
+	mfspr	r10, SPRN_SDAR
+	std	r7, HSTATE_MMCR0(r13)
+	std	r5, HSTATE_MMCR1(r13)
+	std	r6, HSTATE_MMCRA(r13)
+	std	r9, HSTATE_SIAR(r13)
+	std	r10, HSTATE_SDAR(r13)
+BEGIN_FTR_SECTION
+	mfspr	r9, SPRN_SIER
+	std	r8, HSTATE_MMCR2(r13)
+	std	r9, HSTATE_SIER(r13)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+	mfspr	r3, SPRN_PMC1
+	mfspr	r5, SPRN_PMC2
+	mfspr	r6, SPRN_PMC3
+	mfspr	r7, SPRN_PMC4
+	mfspr	r8, SPRN_PMC5
+	mfspr	r9, SPRN_PMC6
+	stw	r3, HSTATE_PMC1(r13)
+	stw	r5, HSTATE_PMC2(r13)
+	stw	r6, HSTATE_PMC3(r13)
+	stw	r7, HSTATE_PMC4(r13)
+	stw	r8, HSTATE_PMC5(r13)
+	stw	r9, HSTATE_PMC6(r13)
+31:	blr
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 6752da1..5b2ae34 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -28,6 +28,7 @@
 #include <asm/exception-64s.h>
 #include <asm/kvm_book3s_asm.h>
 #include <asm/book3s/64/mmu-hash.h>
+#include <asm/export.h>
 #include <asm/tm.h>
 #include <asm/opal.h>
 #include <asm/xive-regs.h>
@@ -113,45 +114,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
 	mtspr	SPRN_SPRG_VDSO_WRITE,r3
 
 	/* Reload the host's PMU registers */
-	lbz	r4, PACA_PMCINUSE(r13) /* is the host using the PMU? */
-	cmpwi	r4, 0
-	beq	23f			/* skip if not */
-BEGIN_FTR_SECTION
-	ld	r3, HSTATE_MMCR0(r13)
-	andi.	r4, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO
-	cmpwi	r4, MMCR0_PMAO
-	beql	kvmppc_fix_pmao
-END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)
-	lwz	r3, HSTATE_PMC1(r13)
-	lwz	r4, HSTATE_PMC2(r13)
-	lwz	r5, HSTATE_PMC3(r13)
-	lwz	r6, HSTATE_PMC4(r13)
-	lwz	r8, HSTATE_PMC5(r13)
-	lwz	r9, HSTATE_PMC6(r13)
-	mtspr	SPRN_PMC1, r3
-	mtspr	SPRN_PMC2, r4
-	mtspr	SPRN_PMC3, r5
-	mtspr	SPRN_PMC4, r6
-	mtspr	SPRN_PMC5, r8
-	mtspr	SPRN_PMC6, r9
-	ld	r3, HSTATE_MMCR0(r13)
-	ld	r4, HSTATE_MMCR1(r13)
-	ld	r5, HSTATE_MMCRA(r13)
-	ld	r6, HSTATE_SIAR(r13)
-	ld	r7, HSTATE_SDAR(r13)
-	mtspr	SPRN_MMCR1, r4
-	mtspr	SPRN_MMCRA, r5
-	mtspr	SPRN_SIAR, r6
-	mtspr	SPRN_SDAR, r7
-BEGIN_FTR_SECTION
-	ld	r8, HSTATE_MMCR2(r13)
-	ld	r9, HSTATE_SIER(r13)
-	mtspr	SPRN_MMCR2, r8
-	mtspr	SPRN_SIER, r9
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-	mtspr	SPRN_MMCR0, r3
-	isync
-23:
+	bl	kvmhv_load_host_pmu
 
 	/*
 	 * Reload DEC.  HDEC interrupts were disabled when
@@ -805,57 +768,12 @@ END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 91:
 #endif
 
-	/* Load guest PMU registers */
-	/* R4 is live here (vcpu pointer) */
-	li	r3, 1
-	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
-	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable ints */
-	isync
-BEGIN_FTR_SECTION
-	ld	r3, VCPU_MMCR(r4)
-	andi.	r5, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO
-	cmpwi	r5, MMCR0_PMAO
-	beql	kvmppc_fix_pmao
-END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)
-	lwz	r3, VCPU_PMC(r4)	/* always load up guest PMU registers */
-	lwz	r5, VCPU_PMC + 4(r4)	/* to prevent information leak */
-	lwz	r6, VCPU_PMC + 8(r4)
-	lwz	r7, VCPU_PMC + 12(r4)
-	lwz	r8, VCPU_PMC + 16(r4)
-	lwz	r9, VCPU_PMC + 20(r4)
-	mtspr	SPRN_PMC1, r3
-	mtspr	SPRN_PMC2, r5
-	mtspr	SPRN_PMC3, r6
-	mtspr	SPRN_PMC4, r7
-	mtspr	SPRN_PMC5, r8
-	mtspr	SPRN_PMC6, r9
-	ld	r3, VCPU_MMCR(r4)
-	ld	r5, VCPU_MMCR + 8(r4)
-	ld	r6, VCPU_MMCR + 16(r4)
-	ld	r7, VCPU_SIAR(r4)
-	ld	r8, VCPU_SDAR(r4)
-	mtspr	SPRN_MMCR1, r5
-	mtspr	SPRN_MMCRA, r6
-	mtspr	SPRN_SIAR, r7
-	mtspr	SPRN_SDAR, r8
-BEGIN_FTR_SECTION
-	ld	r5, VCPU_MMCR + 24(r4)
-	ld	r6, VCPU_SIER(r4)
-	mtspr	SPRN_MMCR2, r5
-	mtspr	SPRN_SIER, r6
-BEGIN_FTR_SECTION_NESTED(96)
-	lwz	r7, VCPU_PMC + 24(r4)
-	lwz	r8, VCPU_PMC + 28(r4)
-	ld	r9, VCPU_MMCR + 32(r4)
-	mtspr	SPRN_SPMC1, r7
-	mtspr	SPRN_SPMC2, r8
-	mtspr	SPRN_MMCRS, r9
-END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-	mtspr	SPRN_MMCR0, r3
-	isync
+	/* Load guest PMU registers; r4 = vcpu pointer here */
+	mr	r3, r4
+	bl	kvmhv_load_guest_pmu
 
 	/* Load up FP, VMX and VSX registers */
+	ld	r4, HSTATE_KVM_VCPU(r13)
 	bl	kvmppc_load_fp
 
 	ld	r14, VCPU_GPR(R14)(r4)
@@ -1766,83 +1684,12 @@ END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 25:
 	/* Save PMU registers if requested */
 	/* r8 and cr0.eq are live here */
-BEGIN_FTR_SECTION
-	/*
-	 * POWER8 seems to have a hardware bug where setting
-	 * MMCR0[PMAE] along with MMCR0[PMC1CE] and/or MMCR0[PMCjCE]
-	 * when some counters are already negative doesn't seem
-	 * to cause a performance monitor alert (and hence interrupt).
-	 * The effect of this is that when saving the PMU state,
-	 * if there is no PMU alert pending when we read MMCR0
-	 * before freezing the counters, but one becomes pending
-	 * before we read the counters, we lose it.
-	 * To work around this, we need a way to freeze the counters
-	 * before reading MMCR0.  Normally, freezing the counters
-	 * is done by writing MMCR0 (to set MMCR0[FC]) which
-	 * unavoidably writes MMCR0[PMA0] as well.  On POWER8,
-	 * we can also freeze the counters using MMCR2, by writing
-	 * 1s to all the counter freeze condition bits (there are
-	 * 9 bits each for 6 counters).
-	 */
-	li	r3, -1			/* set all freeze bits */
-	clrrdi	r3, r3, 10
-	mfspr	r10, SPRN_MMCR2
-	mtspr	SPRN_MMCR2, r3
-	isync
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-	li	r3, 1
-	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
-	mfspr	r4, SPRN_MMCR0		/* save MMCR0 */
-	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable ints */
-	mfspr	r6, SPRN_MMCRA
-	/* Clear MMCRA in order to disable SDAR updates */
-	li	r7, 0
-	mtspr	SPRN_MMCRA, r7
-	isync
+	mr	r3, r9
+	li	r4, 1
 	beq	21f			/* if no VPA, save PMU stuff anyway */
-	lbz	r7, LPPACA_PMCINUSE(r8)
-	cmpwi	r7, 0			/* did they ask for PMU stuff to be saved? */
-	bne	21f
-	std	r3, VCPU_MMCR(r9)	/* if not, set saved MMCR0 to FC */
-	b	22f
-21:	mfspr	r5, SPRN_MMCR1
-	mfspr	r7, SPRN_SIAR
-	mfspr	r8, SPRN_SDAR
-	std	r4, VCPU_MMCR(r9)
-	std	r5, VCPU_MMCR + 8(r9)
-	std	r6, VCPU_MMCR + 16(r9)
-BEGIN_FTR_SECTION
-	std	r10, VCPU_MMCR + 24(r9)
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-	std	r7, VCPU_SIAR(r9)
-	std	r8, VCPU_SDAR(r9)
-	mfspr	r3, SPRN_PMC1
-	mfspr	r4, SPRN_PMC2
-	mfspr	r5, SPRN_PMC3
-	mfspr	r6, SPRN_PMC4
-	mfspr	r7, SPRN_PMC5
-	mfspr	r8, SPRN_PMC6
-	stw	r3, VCPU_PMC(r9)
-	stw	r4, VCPU_PMC + 4(r9)
-	stw	r5, VCPU_PMC + 8(r9)
-	stw	r6, VCPU_PMC + 12(r9)
-	stw	r7, VCPU_PMC + 16(r9)
-	stw	r8, VCPU_PMC + 20(r9)
-BEGIN_FTR_SECTION
-	mfspr	r5, SPRN_SIER
-	std	r5, VCPU_SIER(r9)
-BEGIN_FTR_SECTION_NESTED(96)
-	mfspr	r6, SPRN_SPMC1
-	mfspr	r7, SPRN_SPMC2
-	mfspr	r8, SPRN_MMCRS
-	stw	r6, VCPU_PMC + 24(r9)
-	stw	r7, VCPU_PMC + 28(r9)
-	std	r8, VCPU_MMCR + 32(r9)
-	lis	r4, 0x8000
-	mtspr	SPRN_MMCRS, r4
-END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
-22:
+	lbz	r4, LPPACA_PMCINUSE(r8)
+21:	bl	kvmhv_save_guest_pmu
+	ld	r9, HSTATE_KVM_VCPU(r13)
 
 	/* Restore host values of some registers */
 BEGIN_FTR_SECTION
@@ -3388,6 +3235,194 @@ kvmppc_msr_interrupt:
 	blr
 
 /*
+ * Load up guest PMU state.  R3 points to the vcpu struct.
+ */
+_GLOBAL(kvmhv_load_guest_pmu)
+EXPORT_SYMBOL_GPL(kvmhv_load_guest_pmu)
+	mr	r4, r3
+	mflr	r0
+	li	r3, 1
+	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
+	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable ints */
+	isync
+BEGIN_FTR_SECTION
+	ld	r3, VCPU_MMCR(r4)
+	andi.	r5, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO
+	cmpwi	r5, MMCR0_PMAO
+	beql	kvmppc_fix_pmao
+END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)
+	lwz	r3, VCPU_PMC(r4)	/* always load up guest PMU registers */
+	lwz	r5, VCPU_PMC + 4(r4)	/* to prevent information leak */
+	lwz	r6, VCPU_PMC + 8(r4)
+	lwz	r7, VCPU_PMC + 12(r4)
+	lwz	r8, VCPU_PMC + 16(r4)
+	lwz	r9, VCPU_PMC + 20(r4)
+	mtspr	SPRN_PMC1, r3
+	mtspr	SPRN_PMC2, r5
+	mtspr	SPRN_PMC3, r6
+	mtspr	SPRN_PMC4, r7
+	mtspr	SPRN_PMC5, r8
+	mtspr	SPRN_PMC6, r9
+	ld	r3, VCPU_MMCR(r4)
+	ld	r5, VCPU_MMCR + 8(r4)
+	ld	r6, VCPU_MMCR + 16(r4)
+	ld	r7, VCPU_SIAR(r4)
+	ld	r8, VCPU_SDAR(r4)
+	mtspr	SPRN_MMCR1, r5
+	mtspr	SPRN_MMCRA, r6
+	mtspr	SPRN_SIAR, r7
+	mtspr	SPRN_SDAR, r8
+BEGIN_FTR_SECTION
+	ld	r5, VCPU_MMCR + 24(r4)
+	ld	r6, VCPU_SIER(r4)
+	mtspr	SPRN_MMCR2, r5
+	mtspr	SPRN_SIER, r6
+BEGIN_FTR_SECTION_NESTED(96)
+	lwz	r7, VCPU_PMC + 24(r4)
+	lwz	r8, VCPU_PMC + 28(r4)
+	ld	r9, VCPU_MMCR + 32(r4)
+	mtspr	SPRN_SPMC1, r7
+	mtspr	SPRN_SPMC2, r8
+	mtspr	SPRN_MMCRS, r9
+END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+	mtspr	SPRN_MMCR0, r3
+	isync
+	mtlr	r0
+	blr
+
+/*
+ * Reload host PMU state saved in the PACA by kvmhv_save_host_pmu.
+ */
+_GLOBAL(kvmhv_load_host_pmu)
+EXPORT_SYMBOL_GPL(kvmhv_load_host_pmu)
+	mflr	r0
+	lbz	r4, PACA_PMCINUSE(r13) /* is the host using the PMU? */
+	cmpwi	r4, 0
+	beq	23f			/* skip if not */
+BEGIN_FTR_SECTION
+	ld	r3, HSTATE_MMCR0(r13)
+	andi.	r4, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO
+	cmpwi	r4, MMCR0_PMAO
+	beql	kvmppc_fix_pmao
+END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG)
+	lwz	r3, HSTATE_PMC1(r13)
+	lwz	r4, HSTATE_PMC2(r13)
+	lwz	r5, HSTATE_PMC3(r13)
+	lwz	r6, HSTATE_PMC4(r13)
+	lwz	r8, HSTATE_PMC5(r13)
+	lwz	r9, HSTATE_PMC6(r13)
+	mtspr	SPRN_PMC1, r3
+	mtspr	SPRN_PMC2, r4
+	mtspr	SPRN_PMC3, r5
+	mtspr	SPRN_PMC4, r6
+	mtspr	SPRN_PMC5, r8
+	mtspr	SPRN_PMC6, r9
+	ld	r3, HSTATE_MMCR0(r13)
+	ld	r4, HSTATE_MMCR1(r13)
+	ld	r5, HSTATE_MMCRA(r13)
+	ld	r6, HSTATE_SIAR(r13)
+	ld	r7, HSTATE_SDAR(r13)
+	mtspr	SPRN_MMCR1, r4
+	mtspr	SPRN_MMCRA, r5
+	mtspr	SPRN_SIAR, r6
+	mtspr	SPRN_SDAR, r7
+BEGIN_FTR_SECTION
+	ld	r8, HSTATE_MMCR2(r13)
+	ld	r9, HSTATE_SIER(r13)
+	mtspr	SPRN_MMCR2, r8
+	mtspr	SPRN_SIER, r9
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+	mtspr	SPRN_MMCR0, r3
+	isync
+	mtlr	r0
+23:	blr
+
+/*
+ * Save guest PMU state into the vcpu struct.
+ * r3 = vcpu, r4 = full save flag (PMU in use flag set in VPA)
+ */
+_GLOBAL(kvmhv_save_guest_pmu)
+EXPORT_SYMBOL_GPL(kvmhv_save_guest_pmu)
+	mr	r9, r3
+	mr	r8, r4
+BEGIN_FTR_SECTION
+	/*
+	 * POWER8 seems to have a hardware bug where setting
+	 * MMCR0[PMAE] along with MMCR0[PMC1CE] and/or MMCR0[PMCjCE]
+	 * when some counters are already negative doesn't seem
+	 * to cause a performance monitor alert (and hence interrupt).
+	 * The effect of this is that when saving the PMU state,
+	 * if there is no PMU alert pending when we read MMCR0
+	 * before freezing the counters, but one becomes pending
+	 * before we read the counters, we lose it.
+	 * To work around this, we need a way to freeze the counters
+	 * before reading MMCR0.  Normally, freezing the counters
+	 * is done by writing MMCR0 (to set MMCR0[FC]) which
+	 * unavoidably writes MMCR0[PMA0] as well.  On POWER8,
+	 * we can also freeze the counters using MMCR2, by writing
+	 * 1s to all the counter freeze condition bits (there are
+	 * 9 bits each for 6 counters).
+	 */
+	li	r3, -1			/* set all freeze bits */
+	clrrdi	r3, r3, 10
+	mfspr	r10, SPRN_MMCR2
+	mtspr	SPRN_MMCR2, r3
+	isync
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+	li	r3, 1
+	sldi	r3, r3, 31		/* MMCR0_FC (freeze counters) bit */
+	mfspr	r4, SPRN_MMCR0		/* save MMCR0 */
+	mtspr	SPRN_MMCR0, r3		/* freeze all counters, disable ints */
+	mfspr	r6, SPRN_MMCRA
+	/* Clear MMCRA in order to disable SDAR updates */
+	li	r7, 0
+	mtspr	SPRN_MMCRA, r7
+	isync
+	cmpwi	r8, 0			/* did they ask for PMU stuff to be saved? */
+	bne	21f
+	std	r3, VCPU_MMCR(r9)	/* if not, set saved MMCR0 to FC */
+	b	22f
+21:	mfspr	r5, SPRN_MMCR1
+	mfspr	r7, SPRN_SIAR
+	mfspr	r8, SPRN_SDAR
+	std	r4, VCPU_MMCR(r9)
+	std	r5, VCPU_MMCR + 8(r9)
+	std	r6, VCPU_MMCR + 16(r9)
+BEGIN_FTR_SECTION
+	std	r10, VCPU_MMCR + 24(r9)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+	std	r7, VCPU_SIAR(r9)
+	std	r8, VCPU_SDAR(r9)
+	mfspr	r3, SPRN_PMC1
+	mfspr	r4, SPRN_PMC2
+	mfspr	r5, SPRN_PMC3
+	mfspr	r6, SPRN_PMC4
+	mfspr	r7, SPRN_PMC5
+	mfspr	r8, SPRN_PMC6
+	stw	r3, VCPU_PMC(r9)
+	stw	r4, VCPU_PMC + 4(r9)
+	stw	r5, VCPU_PMC + 8(r9)
+	stw	r6, VCPU_PMC + 12(r9)
+	stw	r7, VCPU_PMC + 16(r9)
+	stw	r8, VCPU_PMC + 20(r9)
+BEGIN_FTR_SECTION
+	mfspr	r5, SPRN_SIER
+	std	r5, VCPU_SIER(r9)
+BEGIN_FTR_SECTION_NESTED(96)
+	mfspr	r6, SPRN_SPMC1
+	mfspr	r7, SPRN_SPMC2
+	mfspr	r8, SPRN_MMCRS
+	stw	r6, VCPU_PMC + 24(r9)
+	stw	r7, VCPU_PMC + 28(r9)
+	std	r8, VCPU_MMCR + 32(r9)
+	lis	r4, 0x8000
+	mtspr	SPRN_MMCRS, r4
+END_FTR_SECTION_NESTED(CPU_FTR_ARCH_300, 0, 96)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+22:	blr
+
+/*
  * This works around a hardware bug on POWER8E processors, where
  * writing a 1 to the MMCR0[PMAO] bit doesn't generate a
  * performance monitor interrupt.  Instead, when we need to have
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 06/32] KVM: PPC: Book3S HV: Simplify real-mode interrupt handling
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This streamlines the first part of the code that handles a hypervisor
interrupt that occurred in the guest.  With this, all of the real-mode
handling that occurs is done before the "guest_exit_cont" label; once
we get to that label we are committed to exiting to host virtual mode.
Thus the machine check and HMI real-mode handling is moved before that
label.

Also, the code to handle external interrupts is moved out of line, as
is the code that calls kvmppc_realmode_hmi_handler().

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kvm/book3s_hv_ras.c        |   8 ++
 arch/powerpc/kvm/book3s_hv_rmhandlers.S | 220 ++++++++++++++++----------------
 2 files changed, 119 insertions(+), 109 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_ras.c b/arch/powerpc/kvm/book3s_hv_ras.c
index b11043b..ee564b6 100644
--- a/arch/powerpc/kvm/book3s_hv_ras.c
+++ b/arch/powerpc/kvm/book3s_hv_ras.c
@@ -331,5 +331,13 @@ long kvmppc_realmode_hmi_handler(void)
 	} else {
 		wait_for_tb_resync();
 	}
+
+	/*
+	 * Reset tb_offset_applied so the guest exit code won't try
+	 * to subtract the previous timebase offset from the timebase.
+	 */
+	if (local_paca->kvm_hstate.kvm_vcore)
+		local_paca->kvm_hstate.kvm_vcore->tb_offset_applied = 0;
+
 	return 0;
 }
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 5b2ae34..772740d 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1018,8 +1018,7 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 no_xive:
 #endif /* CONFIG_KVM_XICS */
 
-deliver_guest_interrupt:
-kvmppc_cede_reentry:		/* r4 = vcpu, r13 = paca */
+deliver_guest_interrupt:	/* r4 = vcpu, r13 = paca */
 	/* Check if we can deliver an external or decrementer interrupt now */
 	ld	r0, VCPU_PENDING_EXC(r4)
 BEGIN_FTR_SECTION
@@ -1269,18 +1268,26 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 	std	r3, VCPU_CTR(r9)
 	std	r4, VCPU_XER(r9)
 
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	/* For softpatch interrupt, go off and do TM instruction emulation */
-	cmpwi	r12, BOOK3S_INTERRUPT_HV_SOFTPATCH
-	beq	kvmppc_tm_emul
-#endif
+	/* Save more register state  */
+	mfdar	r6
+	mfdsisr	r7
+	std	r6, VCPU_DAR(r9)
+	stw	r7, VCPU_DSISR(r9)
 
 	/* If this is a page table miss then see if it's theirs or ours */
 	cmpwi	r12, BOOK3S_INTERRUPT_H_DATA_STORAGE
 	beq	kvmppc_hdsi
+	std	r6, VCPU_FAULT_DAR(r9)
+	stw	r7, VCPU_FAULT_DSISR(r9)
 	cmpwi	r12, BOOK3S_INTERRUPT_H_INST_STORAGE
 	beq	kvmppc_hisi
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* For softpatch interrupt, go off and do TM instruction emulation */
+	cmpwi	r12, BOOK3S_INTERRUPT_HV_SOFTPATCH
+	beq	kvmppc_tm_emul
+#endif
+
 	/* See if this is a leftover HDEC interrupt */
 	cmpwi	r12,BOOK3S_INTERRUPT_HV_DECREMENTER
 	bne	2f
@@ -1303,7 +1310,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	lbz	r0, HSTATE_HOST_IPI(r13)
 	cmpwi	r0, 0
-	beq	4f
+	beq	maybe_reenter_guest
 	b	guest_exit_cont
 3:
 	/* If it's a hypervisor facility unavailable interrupt, save HFSCR */
@@ -1315,82 +1322,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 14:
 	/* External interrupt ? */
 	cmpwi	r12, BOOK3S_INTERRUPT_EXTERNAL
-	bne+	guest_exit_cont
-
-	/* External interrupt, first check for host_ipi. If this is
-	 * set, we know the host wants us out so let's do it now
-	 */
-	bl	kvmppc_read_intr
-
-	/*
-	 * Restore the active volatile registers after returning from
-	 * a C function.
-	 */
-	ld	r9, HSTATE_KVM_VCPU(r13)
-	li	r12, BOOK3S_INTERRUPT_EXTERNAL
-
-	/*
-	 * kvmppc_read_intr return codes:
-	 *
-	 * Exit to host (r3 > 0)
-	 *   1 An interrupt is pending that needs to be handled by the host
-	 *     Exit guest and return to host by branching to guest_exit_cont
-	 *
-	 *   2 Passthrough that needs completion in the host
-	 *     Exit guest and return to host by branching to guest_exit_cont
-	 *     However, we also set r12 to BOOK3S_INTERRUPT_HV_RM_HARD
-	 *     to indicate to the host to complete handling the interrupt
-	 *
-	 * Before returning to guest, we check if any CPU is heading out
-	 * to the host and if so, we head out also. If no CPUs are heading
-	 * check return values <= 0.
-	 *
-	 * Return to guest (r3 <= 0)
-	 *  0 No external interrupt is pending
-	 * -1 A guest wakeup IPI (which has now been cleared)
-	 *    In either case, we return to guest to deliver any pending
-	 *    guest interrupts.
-	 *
-	 * -2 A PCI passthrough external interrupt was handled
-	 *    (interrupt was delivered directly to guest)
-	 *    Return to guest to deliver any pending guest interrupts.
-	 */
-
-	cmpdi	r3, 1
-	ble	1f
-
-	/* Return code = 2 */
-	li	r12, BOOK3S_INTERRUPT_HV_RM_HARD
-	stw	r12, VCPU_TRAP(r9)
-	b	guest_exit_cont
-
-1:	/* Return code <= 1 */
-	cmpdi	r3, 0
-	bgt	guest_exit_cont
-
-	/* Return code <= 0 */
-4:	ld	r5, HSTATE_KVM_VCORE(r13)
-	lwz	r0, VCORE_ENTRY_EXIT(r5)
-	cmpwi	r0, 0x100
-	mr	r4, r9
-	blt	deliver_guest_interrupt
-
-guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
-	/* Save more register state  */
-	mfdar	r6
-	mfdsisr	r7
-	std	r6, VCPU_DAR(r9)
-	stw	r7, VCPU_DSISR(r9)
-	/* don't overwrite fault_dar/fault_dsisr if HDSI */
-	cmpwi	r12,BOOK3S_INTERRUPT_H_DATA_STORAGE
-	beq	mc_cont
-	std	r6, VCPU_FAULT_DAR(r9)
-	stw	r7, VCPU_FAULT_DSISR(r9)
-
+	beq	kvmppc_guest_external
 	/* See if it is a machine check */
 	cmpwi	r12, BOOK3S_INTERRUPT_MACHINE_CHECK
 	beq	machine_check_realmode
-mc_cont:
+	/* Or a hypervisor maintenance interrupt */
+	cmpwi	r12, BOOK3S_INTERRUPT_HMI
+	beq	hmi_realmode
+
+guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
+
 #ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING
 	addi	r3, r9, VCPU_TB_RMEXIT
 	mr	r4, r9
@@ -1821,24 +1762,6 @@ BEGIN_FTR_SECTION
 	mtspr	SPRN_DPDES, r8
 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 
-	/* If HMI, call kvmppc_realmode_hmi_handler() */
-	lwz	r12, STACK_SLOT_TRAP(r1)
-	cmpwi	r12, BOOK3S_INTERRUPT_HMI
-	bne	27f
-	bl	kvmppc_realmode_hmi_handler
-	nop
-	cmpdi	r3, 0
-	/*
-	 * At this point kvmppc_realmode_hmi_handler may have resync-ed
-	 * the TB, and if it has, we must not subtract the guest timebase
-	 * offset from the timebase. So, skip it.
-	 *
-	 * Also, do not call kvmppc_subcore_exit_guest() because it has
-	 * been invoked as part of kvmppc_realmode_hmi_handler().
-	 */
-	beq	30f
-
-27:
 	/* Subtract timebase offset from timebase */
 	ld	r8, VCORE_TB_OFFSET_APPL(r5)
 	cmpdi	r8,0
@@ -1856,7 +1779,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
 	addis	r8,r8,0x100		/* if so, increment upper 40 bits */
 	mtspr	SPRN_TBU40,r8
 
-17:	bl	kvmppc_subcore_exit_guest
+17:
+	/*
+	 * If this is an HMI, we called kvmppc_realmode_hmi_handler
+	 * above, which may or may not have already called
+	 * kvmppc_subcore_exit_guest.  Fortunately, all that
+	 * kvmppc_subcore_exit_guest does is clear a flag, so calling
+	 * it again here is benign even if kvmppc_realmode_hmi_handler
+	 * has already called it.
+	 */
+	bl	kvmppc_subcore_exit_guest
 	nop
 30:	ld	r5,HSTATE_KVM_VCORE(r13)
 	ld	r4,VCORE_KVM(r5)	/* pointer to struct kvm */
@@ -1910,6 +1842,67 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	mtlr	r0
 	blr
 
+kvmppc_guest_external:
+	/* External interrupt, first check for host_ipi. If this is
+	 * set, we know the host wants us out so let's do it now
+	 */
+	bl	kvmppc_read_intr
+
+	/*
+	 * Restore the active volatile registers after returning from
+	 * a C function.
+	 */
+	ld	r9, HSTATE_KVM_VCPU(r13)
+	li	r12, BOOK3S_INTERRUPT_EXTERNAL
+
+	/*
+	 * kvmppc_read_intr return codes:
+	 *
+	 * Exit to host (r3 > 0)
+	 *   1 An interrupt is pending that needs to be handled by the host
+	 *     Exit guest and return to host by branching to guest_exit_cont
+	 *
+	 *   2 Passthrough that needs completion in the host
+	 *     Exit guest and return to host by branching to guest_exit_cont
+	 *     However, we also set r12 to BOOK3S_INTERRUPT_HV_RM_HARD
+	 *     to indicate to the host to complete handling the interrupt
+	 *
+	 * Before returning to guest, we check if any CPU is heading out
+	 * to the host and if so, we head out also. If no CPUs are heading
+	 * check return values <= 0.
+	 *
+	 * Return to guest (r3 <= 0)
+	 *  0 No external interrupt is pending
+	 * -1 A guest wakeup IPI (which has now been cleared)
+	 *    In either case, we return to guest to deliver any pending
+	 *    guest interrupts.
+	 *
+	 * -2 A PCI passthrough external interrupt was handled
+	 *    (interrupt was delivered directly to guest)
+	 *    Return to guest to deliver any pending guest interrupts.
+	 */
+
+	cmpdi	r3, 1
+	ble	1f
+
+	/* Return code = 2 */
+	li	r12, BOOK3S_INTERRUPT_HV_RM_HARD
+	stw	r12, VCPU_TRAP(r9)
+	b	guest_exit_cont
+
+1:	/* Return code <= 1 */
+	cmpdi	r3, 0
+	bgt	guest_exit_cont
+
+	/* Return code <= 0 */
+maybe_reenter_guest:
+	ld	r5, HSTATE_KVM_VCORE(r13)
+	lwz	r0, VCORE_ENTRY_EXIT(r5)
+	cmpwi	r0, 0x100
+	mr	r4, r9
+	blt	deliver_guest_interrupt
+	b	guest_exit_cont
+
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 /*
  * Softpatch interrupt for transactional memory emulation cases
@@ -2685,13 +2678,7 @@ END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	mr	r9, r4
 	cmpdi	r3, 0
 	bgt	guest_exit_cont
-
-	/* see if any other thread is already exiting */
-	lwz	r0,VCORE_ENTRY_EXIT(r5)
-	cmpwi	r0,0x100
-	bge	guest_exit_cont
-
-	b	kvmppc_cede_reentry	/* if not go back to guest */
+	b	maybe_reenter_guest
 
 	/* cede when already previously prodded case */
 kvm_cede_prodded:
@@ -2758,12 +2745,12 @@ machine_check_realmode:
 	 */
 	ld	r11, VCPU_MSR(r9)
 	rldicl.	r0, r11, 64-MSR_HV_LG, 63 /* check if it happened in HV mode */
-	bne	mc_cont			/* if so, exit to host */
+	bne	guest_exit_cont		/* if so, exit to host */
 	/* Check if guest is capable of handling NMI exit */
 	ld	r10, VCPU_KVM(r9)
 	lbz	r10, KVM_FWNMI(r10)
 	cmpdi	r10, 1			/* FWNMI capable? */
-	beq	mc_cont			/* if so, exit with KVM_EXIT_NMI. */
+	beq	guest_exit_cont		/* if so, exit with KVM_EXIT_NMI. */
 
 	/* if not, fall through for backward compatibility. */
 	andi.	r10, r11, MSR_RI	/* check for unrecoverable exception */
@@ -2777,6 +2764,21 @@ machine_check_realmode:
 2:	b	fast_interrupt_c_return
 
 /*
+ * Call C code to handle a HMI in real mode.
+ * Only the primary thread does the call, secondary threads are handled
+ * by calling hmi_exception_realmode() after kvmppc_hv_entry returns.
+ * r9 points to the vcpu on entry
+ */
+hmi_realmode:
+	lbz	r0, HSTATE_PTID(r13)
+	cmpwi	r0, 0
+	bne	guest_exit_cont
+	bl	kvmppc_realmode_hmi_handler
+	ld	r9, HSTATE_KVM_VCPU(r13)
+	li	r12, BOOK3S_INTERRUPT_HMI
+	b	guest_exit_cont
+
+/*
  * Check the reason we woke from nap, and take appropriate action.
  * Returns (in r3):
  *	0 if nothing needs to be done
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 07/32] KVM: PPC: Book3S: Rework TM save/restore code and make it C-callable
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This adds a parameter to __kvmppc_save_tm and __kvmppc_restore_tm
which allows the caller to indicate whether it wants the nonvolatile
register state to be preserved across the call, as required by the C
calling conventions.  This parameter being non-zero also causes the
MSR bits that enable TM, FP, VMX and VSX to be preserved.  The
condition register and DSCR are now always preserved.

With this, kvmppc_save_tm_hv and kvmppc_restore_tm_hv can be called
from C code provided the 3rd parameter is non-zero.  So that these
functions can be called from modules, they now include code to set
the TOC pointer (r2) on entry, as they can call other built-in C
functions which will assume the TOC to have been set.

Also, the fake suspend code in kvmppc_save_tm_hv is modified here to
assume that treclaim in fake-suspend state does not modify any registers,
which is the case on POWER9.  This enables the code to be simplified
quite a bit.

_kvmppc_save_tm_pr and _kvmppc_restore_tm_pr become much simpler with
this change, since they now only need to save and restore TAR and pass
1 for the 3rd argument to __kvmppc_{save,restore}_tm.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/asm-prototypes.h |  10 ++
 arch/powerpc/kvm/book3s_hv_rmhandlers.S   |  49 +++---
 arch/powerpc/kvm/tm.S                     | 250 ++++++++++++++++--------------
 3 files changed, 169 insertions(+), 140 deletions(-)

diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 024e8fc..0c1a2b0 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -150,6 +150,16 @@ extern s32 patch__memset_nocache, patch__memcpy_nocache;
 
 extern long flush_count_cache;
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+void kvmppc_save_tm_hv(struct kvm_vcpu *vcpu, u64 msr, bool preserve_nv);
+void kvmppc_restore_tm_hv(struct kvm_vcpu *vcpu, u64 msr, bool preserve_nv);
+#else
+static inline void kvmppc_save_tm_hv(struct kvm_vcpu *vcpu, u64 msr,
+				     bool preserve_nv) { }
+static inline void kvmppc_restore_tm_hv(struct kvm_vcpu *vcpu, u64 msr,
+					bool preserve_nv) { }
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+
 void kvmhv_save_host_pmu(void);
 void kvmhv_load_host_pmu(void);
 void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use);
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 772740d..67a847f 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -759,11 +759,13 @@ BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
-	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
+	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
 	mr      r3, r4
 	ld      r4, VCPU_MSR(r3)
+	li	r5, 0			/* don't preserve non-vol regs */
 	bl	kvmppc_restore_tm_hv
+	nop
 	ld	r4, HSTATE_KVM_VCPU(r13)
 91:
 #endif
@@ -1603,11 +1605,13 @@ BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
-	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
+	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
 	mr      r3, r9
 	ld      r4, VCPU_MSR(r3)
+	li	r5, 0			/* don't preserve non-vol regs */
 	bl	kvmppc_save_tm_hv
+	nop
 	ld	r9, HSTATE_KVM_VCPU(r13)
 91:
 #endif
@@ -2486,11 +2490,13 @@ BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
-	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
+	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
 	ld	r3, HSTATE_KVM_VCPU(r13)
 	ld      r4, VCPU_MSR(r3)
+	li	r5, 0			/* don't preserve non-vol regs */
 	bl	kvmppc_save_tm_hv
+	nop
 91:
 #endif
 
@@ -2606,11 +2612,13 @@ BEGIN_FTR_SECTION
 	b	91f
 END_FTR_SECTION(CPU_FTR_TM | CPU_FTR_P9_TM_HV_ASSIST, 0)
 	/*
-	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS INCLUDING CR
+	 * NOTE THAT THIS TRASHES ALL NON-VOLATILE REGISTERS (but not CR)
 	 */
 	mr      r3, r4
 	ld      r4, VCPU_MSR(r3)
+	li	r5, 0			/* don't preserve non-vol regs */
 	bl	kvmppc_restore_tm_hv
+	nop
 	ld	r4, HSTATE_KVM_VCPU(r13)
 91:
 #endif
@@ -2943,10 +2951,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
  * Save transactional state and TM-related registers.
  * Called with r3 pointing to the vcpu struct and r4 containing
  * the guest MSR value.
- * This can modify all checkpointed registers, but
+ * r5 is non-zero iff non-volatile register state needs to be maintained.
+ * If r5 == 0, this can modify all checkpointed registers, but
  * restores r1 and r2 before exit.
  */
-kvmppc_save_tm_hv:
+_GLOBAL_TOC(kvmppc_save_tm_hv)
+EXPORT_SYMBOL_GPL(kvmppc_save_tm_hv)
 	/* See if we need to handle fake suspend mode */
 BEGIN_FTR_SECTION
 	b	__kvmppc_save_tm
@@ -2974,12 +2984,6 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG)
 	nop
 
-	std	r1, HSTATE_HOST_R1(r13)
-
-	/* Clear the MSR RI since r1, r13 may be foobar. */
-	li	r5, 0
-	mtmsrd	r5, 1
-
 	/* We have to treclaim here because that's the only way to do S->N */
 	li	r3, TM_CAUSE_KVM_RESCHED
 	TRECLAIM(R3)
@@ -2988,22 +2992,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG)
 	 * We were in fake suspend, so we are not going to save the
 	 * register state as the guest checkpointed state (since
 	 * we already have it), therefore we can now use any volatile GPR.
+	 * In fact treclaim in fake suspend state doesn't modify
+	 * any registers.
 	 */
-	/* Reload PACA pointer, stack pointer and TOC. */
-	GET_PACA(r13)
-	ld	r1, HSTATE_HOST_R1(r13)
-	ld	r2, PACATOC(r13)
 
-	/* Set MSR RI now we have r1 and r13 back. */
-	li	r5, MSR_RI
-	mtmsrd	r5, 1
-
-	HMT_MEDIUM
-	ld	r6, HSTATE_DSCR(r13)
-	mtspr	SPRN_DSCR, r6
-BEGIN_FTR_SECTION_NESTED(96)
+BEGIN_FTR_SECTION
 	bl	pnv_power9_force_smt4_release
-END_FTR_SECTION_NESTED(CPU_FTR_P9_TM_XER_SO_BUG, CPU_FTR_P9_TM_XER_SO_BUG, 96)
+END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG)
 	nop
 
 4:
@@ -3029,10 +3024,12 @@ END_FTR_SECTION_NESTED(CPU_FTR_P9_TM_XER_SO_BUG, CPU_FTR_P9_TM_XER_SO_BUG, 96)
  * Restore transactional state and TM-related registers.
  * Called with r3 pointing to the vcpu struct
  * and r4 containing the guest MSR value.
+ * r5 is non-zero iff non-volatile register state needs to be maintained.
  * This potentially modifies all checkpointed registers.
  * It restores r1 and r2 from the PACA.
  */
-kvmppc_restore_tm_hv:
+_GLOBAL_TOC(kvmppc_restore_tm_hv)
+EXPORT_SYMBOL_GPL(kvmppc_restore_tm_hv)
 	/*
 	 * If we are doing TM emulation for the guest on a POWER9 DD2,
 	 * then we don't actually do a trechkpt -- we either set up
diff --git a/arch/powerpc/kvm/tm.S b/arch/powerpc/kvm/tm.S
index 90e330f..0531a14 100644
--- a/arch/powerpc/kvm/tm.S
+++ b/arch/powerpc/kvm/tm.S
@@ -28,17 +28,25 @@
  * Save transactional state and TM-related registers.
  * Called with:
  * - r3 pointing to the vcpu struct
- * - r4 points to the MSR with current TS bits:
+ * - r4 containing the MSR with current TS bits:
  * 	(For HV KVM, it is VCPU_MSR ; For PR KVM, it is host MSR).
- * This can modify all checkpointed registers, but
- * restores r1, r2 before exit.
+ * - r5 containing a flag indicating that non-volatile registers
+ *	must be preserved.
+ * If r5 == 0, this can modify all checkpointed registers, but
+ * restores r1, r2 before exit.  If r5 != 0, this restores the
+ * MSR TM/FP/VEC/VSX bits to their state on entry.
  */
 _GLOBAL(__kvmppc_save_tm)
 	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
+	stdu    r1, -SWITCH_FRAME_SIZE(r1)
+
+	mr	r9, r3
+	cmpdi	cr7, r5, 0
 
 	/* Turn on TM. */
 	mfmsr	r8
+	mr	r10, r8
 	li	r0, 1
 	rldimi	r8, r0, MSR_TM_LG, 63-MSR_TM_LG
 	ori     r8, r8, MSR_FP
@@ -51,6 +59,27 @@ _GLOBAL(__kvmppc_save_tm)
 	std	r1, HSTATE_SCRATCH2(r13)
 	std	r3, HSTATE_SCRATCH1(r13)
 
+	/* Save CR on the stack - even if r5 == 0 we need to get cr7 back. */
+	mfcr	r6
+	SAVE_GPR(6, r1)
+
+	/* Save DSCR so we can restore it to avoid running with user value */
+	mfspr	r7, SPRN_DSCR
+	SAVE_GPR(7, r1)
+
+	/*
+	 * We are going to do treclaim., which will modify all checkpointed
+	 * registers.  Save the non-volatile registers on the stack if
+	 * preservation of non-volatile state has been requested.
+	 */
+	beq	cr7, 3f
+	SAVE_NVGPRS(r1)
+
+	/* MSR[TS] will be 0 (non-transactional) once we do treclaim. */
+	li	r0, 0
+	rldimi	r10, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+	SAVE_GPR(10, r1)	/* final MSR value */
+3:
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 BEGIN_FTR_SECTION
 	/* Emulation of the treclaim instruction needs TEXASR before treclaim */
@@ -74,22 +103,25 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
 	std	r9, PACATMSCRATCH(r13)
 	ld	r9, HSTATE_SCRATCH1(r13)
 
-	/* Get a few more GPRs free. */
-	std	r29, VCPU_GPRS_TM(29)(r9)
-	std	r30, VCPU_GPRS_TM(30)(r9)
-	std	r31, VCPU_GPRS_TM(31)(r9)
-
-	/* Save away PPR and DSCR soon so don't run with user values. */
-	mfspr	r31, SPRN_PPR
+	/* Save away PPR soon so we don't run with user value. */
+	std	r0, VCPU_GPRS_TM(0)(r9)
+	mfspr	r0, SPRN_PPR
 	HMT_MEDIUM
-	mfspr	r30, SPRN_DSCR
-#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-	ld	r29, HSTATE_DSCR(r13)
-	mtspr	SPRN_DSCR, r29
-#endif
 
-	/* Save all but r9, r13 & r29-r31 */
-	reg = 0
+	/* Reload stack pointer. */
+	std	r1, VCPU_GPRS_TM(1)(r9)
+	ld	r1, HSTATE_SCRATCH2(r13)
+
+	/* Set MSR RI now we have r1 and r13 back. */
+	std	r2, VCPU_GPRS_TM(2)(r9)
+	li	r2, MSR_RI
+	mtmsrd	r2, 1
+
+	/* Reload TOC pointer. */
+	ld	r2, PACATOC(r13)
+
+	/* Save all but r0-r2, r9 & r13 */
+	reg = 3
 	.rept	29
 	.if (reg != 9) && (reg != 13)
 	std	reg, VCPU_GPRS_TM(reg)(r9)
@@ -103,33 +135,29 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
 	ld	r4, PACATMSCRATCH(r13)
 	std	r4, VCPU_GPRS_TM(9)(r9)
 
-	/* Reload stack pointer and TOC. */
-	ld	r1, HSTATE_SCRATCH2(r13)
-	ld	r2, PACATOC(r13)
-
-	/* Set MSR RI now we have r1 and r13 back. */
-	li	r5, MSR_RI
-	mtmsrd	r5, 1
+	/* Restore host DSCR and CR values, after saving guest values */
+	mfcr	r6
+	mfspr	r7, SPRN_DSCR
+	stw	r6, VCPU_CR_TM(r9)
+	std	r7, VCPU_DSCR_TM(r9)
+	REST_GPR(6, r1)
+	REST_GPR(7, r1)
+	mtcr	r6
+	mtspr	SPRN_DSCR, r7
 
-	/* Save away checkpinted SPRs. */
-	std	r31, VCPU_PPR_TM(r9)
-	std	r30, VCPU_DSCR_TM(r9)
+	/* Save away checkpointed SPRs. */
+	std	r0, VCPU_PPR_TM(r9)
 	mflr	r5
-	mfcr	r6
 	mfctr	r7
 	mfspr	r8, SPRN_AMR
 	mfspr	r10, SPRN_TAR
 	mfxer	r11
 	std	r5, VCPU_LR_TM(r9)
-	stw	r6, VCPU_CR_TM(r9)
 	std	r7, VCPU_CTR_TM(r9)
 	std	r8, VCPU_AMR_TM(r9)
 	std	r10, VCPU_TAR_TM(r9)
 	std	r11, VCPU_XER_TM(r9)
 
-	/* Restore r12 as trap number. */
-	lwz	r12, VCPU_TRAP(r9)
-
 	/* Save FP/VSX. */
 	addi	r3, r9, VCPU_FPRS_TM
 	bl	store_fp_state
@@ -137,6 +165,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
 	bl	store_vr_state
 	mfspr	r6, SPRN_VRSAVE
 	stw	r6, VCPU_VRSAVE_TM(r9)
+
+	/* Restore non-volatile registers if requested to */
+	beq	cr7, 1f
+	REST_NVGPRS(r1)
+	REST_GPR(10, r1)
 1:
 	/*
 	 * We need to save these SPRs after the treclaim so that the software
@@ -146,12 +179,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
 	 */
 	mfspr	r7, SPRN_TEXASR
 	std	r7, VCPU_TEXASR(r9)
-11:
 	mfspr	r5, SPRN_TFHAR
 	mfspr	r6, SPRN_TFIAR
 	std	r5, VCPU_TFHAR(r9)
 	std	r6, VCPU_TFIAR(r9)
 
+	/* Restore MSR state if requested */
+	beq	cr7, 2f
+	mtmsrd	r10, 0
+2:
+	addi	r1, r1, SWITCH_FRAME_SIZE
 	ld	r0, PPC_LR_STKOFF(r1)
 	mtlr	r0
 	blr
@@ -161,49 +198,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
  * be invoked from C function by PR KVM only.
  */
 _GLOBAL(_kvmppc_save_tm_pr)
-	mflr	r5
-	std	r5, PPC_LR_STKOFF(r1)
-	stdu    r1, -SWITCH_FRAME_SIZE(r1)
-	SAVE_NVGPRS(r1)
-
-	/* save MSR since TM/math bits might be impacted
-	 * by __kvmppc_save_tm().
-	 */
-	mfmsr	r5
-	SAVE_GPR(5, r1)
-
-	/* also save DSCR/CR/TAR so that it can be recovered later */
-	mfspr   r6, SPRN_DSCR
-	SAVE_GPR(6, r1)
-
-	mfcr    r7
-	stw     r7, _CCR(r1)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+	stdu    r1, -PPC_MIN_STKFRM(r1)
 
 	mfspr   r8, SPRN_TAR
-	SAVE_GPR(8, r1)
+	std	r8, PPC_MIN_STKFRM-8(r1)
 
+	li	r5, 1		/* preserve non-volatile registers */
 	bl	__kvmppc_save_tm
 
-	REST_GPR(8, r1)
+	ld	r8, PPC_MIN_STKFRM-8(r1)
 	mtspr   SPRN_TAR, r8
 
-	ld      r7, _CCR(r1)
-	mtcr	r7
-
-	REST_GPR(6, r1)
-	mtspr   SPRN_DSCR, r6
-
-	/* need preserve current MSR's MSR_TS bits */
-	REST_GPR(5, r1)
-	mfmsr   r6
-	rldicl  r6, r6, 64 - MSR_TS_S_LG, 62
-	rldimi  r5, r6, MSR_TS_S_LG, 63 - MSR_TS_T_LG
-	mtmsrd  r5
-
-	REST_NVGPRS(r1)
-	addi    r1, r1, SWITCH_FRAME_SIZE
-	ld	r5, PPC_LR_STKOFF(r1)
-	mtlr	r5
+	addi    r1, r1, PPC_MIN_STKFRM
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
 	blr
 
 EXPORT_SYMBOL_GPL(_kvmppc_save_tm_pr);
@@ -215,15 +225,21 @@ EXPORT_SYMBOL_GPL(_kvmppc_save_tm_pr);
  *  - r4 is the guest MSR with desired TS bits:
  * 	For HV KVM, it is VCPU_MSR
  * 	For PR KVM, it is provided by caller
- * This potentially modifies all checkpointed registers.
- * It restores r1, r2 from the PACA.
+ * - r5 containing a flag indicating that non-volatile registers
+ *	must be preserved.
+ * If r5 == 0, this potentially modifies all checkpointed registers, but
+ * restores r1, r2 from the PACA before exit.
+ * If r5 != 0, this restores the MSR TM/FP/VEC/VSX bits to their state on entry.
  */
 _GLOBAL(__kvmppc_restore_tm)
 	mflr	r0
 	std	r0, PPC_LR_STKOFF(r1)
 
+	cmpdi	cr7, r5, 0
+
 	/* Turn on TM/FP/VSX/VMX so we can restore them. */
 	mfmsr	r5
+	mr	r10, r5
 	li	r6, MSR_TM >> 32
 	sldi	r6, r6, 32
 	or	r5, r5, r6
@@ -244,8 +260,7 @@ _GLOBAL(__kvmppc_restore_tm)
 
 	mr	r5, r4
 	rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
-	beqlr		/* TM not active in guest */
-	std	r1, HSTATE_SCRATCH2(r13)
+	beq	9f		/* TM not active in guest */
 
 	/* Make sure the failure summary is set, otherwise we'll program check
 	 * when we trechkpt.  It's possible that this might have been not set
@@ -256,6 +271,26 @@ _GLOBAL(__kvmppc_restore_tm)
 	mtspr	SPRN_TEXASR, r7
 
 	/*
+	 * Make a stack frame and save non-volatile registers if requested.
+	 */
+	stdu	r1, -SWITCH_FRAME_SIZE(r1)
+	std	r1, HSTATE_SCRATCH2(r13)
+
+	mfcr	r6
+	mfspr	r7, SPRN_DSCR
+	SAVE_GPR(2, r1)
+	SAVE_GPR(6, r1)
+	SAVE_GPR(7, r1)
+
+	beq	cr7, 4f
+	SAVE_NVGPRS(r1)
+
+	/* MSR[TS] will be 1 (suspended) once we do trechkpt */
+	li	r0, 1
+	rldimi	r10, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+	SAVE_GPR(10, r1)	/* final MSR value */
+4:
+	/*
 	 * We need to load up the checkpointed state for the guest.
 	 * We need to do this early as it will blow away any GPRs, VSRs and
 	 * some SPRs.
@@ -291,8 +326,6 @@ _GLOBAL(__kvmppc_restore_tm)
 	ld	r29, VCPU_DSCR_TM(r3)
 	ld	r30, VCPU_PPR_TM(r3)
 
-	std	r2, PACATMSCRATCH(r13) /* Save TOC */
-
 	/* Clear the MSR RI since r1, r13 are all going to be foobar. */
 	li	r5, 0
 	mtmsrd	r5, 1
@@ -318,18 +351,31 @@ _GLOBAL(__kvmppc_restore_tm)
 	/* Now let's get back the state we need. */
 	HMT_MEDIUM
 	GET_PACA(r13)
-#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-	ld	r29, HSTATE_DSCR(r13)
-	mtspr	SPRN_DSCR, r29
-#endif
 	ld	r1, HSTATE_SCRATCH2(r13)
-	ld	r2, PACATMSCRATCH(r13)
+	REST_GPR(7, r1)
+	mtspr	SPRN_DSCR, r7
 
 	/* Set the MSR RI since we have our registers back. */
 	li	r5, MSR_RI
 	mtmsrd	r5, 1
+
+	/* Restore TOC pointer and CR */
+	REST_GPR(2, r1)
+	REST_GPR(6, r1)
+	mtcr	r6
+
+	/* Restore non-volatile registers if requested to. */
+	beq	cr7, 5f
+	REST_GPR(10, r1)
+	REST_NVGPRS(r1)
+
+5:	addi	r1, r1, SWITCH_FRAME_SIZE
 	ld	r0, PPC_LR_STKOFF(r1)
 	mtlr	r0
+
+9:	/* Restore MSR bits if requested */
+	beqlr	cr7
+	mtmsrd	r10, 0
 	blr
 
 /*
@@ -337,47 +383,23 @@ _GLOBAL(__kvmppc_restore_tm)
  * can be invoked from C function by PR KVM only.
  */
 _GLOBAL(_kvmppc_restore_tm_pr)
-	mflr	r5
-	std	r5, PPC_LR_STKOFF(r1)
-	stdu    r1, -SWITCH_FRAME_SIZE(r1)
-	SAVE_NVGPRS(r1)
-
-	/* save MSR to avoid TM/math bits change */
-	mfmsr	r5
-	SAVE_GPR(5, r1)
-
-	/* also save DSCR/CR/TAR so that it can be recovered later */
-	mfspr   r6, SPRN_DSCR
-	SAVE_GPR(6, r1)
-
-	mfcr    r7
-	stw     r7, _CCR(r1)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+	stdu    r1, -PPC_MIN_STKFRM(r1)
 
+	/* save TAR so that it can be recovered later */
 	mfspr   r8, SPRN_TAR
-	SAVE_GPR(8, r1)
+	std	r8, PPC_MIN_STKFRM-8(r1)
 
+	li	r5, 1
 	bl	__kvmppc_restore_tm
 
-	REST_GPR(8, r1)
+	ld	r8, PPC_MIN_STKFRM-8(r1)
 	mtspr   SPRN_TAR, r8
 
-	ld      r7, _CCR(r1)
-	mtcr	r7
-
-	REST_GPR(6, r1)
-	mtspr   SPRN_DSCR, r6
-
-	/* need preserve current MSR's MSR_TS bits */
-	REST_GPR(5, r1)
-	mfmsr   r6
-	rldicl  r6, r6, 64 - MSR_TS_S_LG, 62
-	rldimi  r5, r6, MSR_TS_S_LG, 63 - MSR_TS_T_LG
-	mtmsrd  r5
-
-	REST_NVGPRS(r1)
-	addi    r1, r1, SWITCH_FRAME_SIZE
-	ld	r5, PPC_LR_STKOFF(r1)
-	mtlr	r5
+	addi    r1, r1, PPC_MIN_STKFRM
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
 	blr
 
 EXPORT_SYMBOL_GPL(_kvmppc_restore_tm_pr);
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 08/32] KVM: PPC: Book3S HV: Call kvmppc_handle_exit_hv() with vcore unlocked
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

Currently kvmppc_handle_exit_hv() is called with the vcore lock held
because it is called within a for_each_runnable_thread loop.
However, we already unlock the vcore within kvmppc_handle_exit_hv()
under certain circumstances, and this is safe because (a) any vcpus
that become runnable and are added to the runnable set by
kvmppc_run_vcpu() have their vcpu->arch.trap == 0 and can't actually
run in the guest (because the vcore state is VCORE_EXITING), and
(b) for_each_runnable_thread is safe against addition or removal
of vcpus from the runnable set.

Therefore, in order to simplify things for following patches, let's
drop the vcore lock in the for_each_runnable_thread loop, so
kvmppc_handle_exit_hv() gets called without the vcore lock held.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kvm/book3s_hv.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 49a686c..0e17593 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1084,7 +1084,6 @@ static int kvmppc_emulate_doorbell_instr(struct kvm_vcpu *vcpu)
 	return RESUME_GUEST;
 }
 
-/* Called with vcpu->arch.vcore->lock held */
 static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu,
 				 struct task_struct *tsk)
 {
@@ -1205,10 +1204,7 @@ static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu,
 				swab32(vcpu->arch.emul_inst) :
 				vcpu->arch.emul_inst;
 		if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP) {
-			/* Need vcore unlocked to call kvmppc_get_last_inst */
-			spin_unlock(&vcpu->arch.vcore->lock);
 			r = kvmppc_emulate_debug_inst(run, vcpu);
-			spin_lock(&vcpu->arch.vcore->lock);
 		} else {
 			kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
 			r = RESUME_GUEST;
@@ -1224,12 +1220,8 @@ static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	case BOOK3S_INTERRUPT_H_FAC_UNAVAIL:
 		r = EMULATE_FAIL;
 		if (((vcpu->arch.hfscr >> 56) == FSCR_MSGP_LG) &&
-		    cpu_has_feature(CPU_FTR_ARCH_300)) {
-			/* Need vcore unlocked to call kvmppc_get_last_inst */
-			spin_unlock(&vcpu->arch.vcore->lock);
+		    cpu_has_feature(CPU_FTR_ARCH_300))
 			r = kvmppc_emulate_doorbell_instr(vcpu);
-			spin_lock(&vcpu->arch.vcore->lock);
-		}
 		if (r == EMULATE_FAIL) {
 			kvmppc_core_queue_program(vcpu, SRR1_PROGILL);
 			r = RESUME_GUEST;
@@ -2599,6 +2591,14 @@ static void post_guest_process(struct kvmppc_vcore *vc, bool is_master)
 	spin_lock(&vc->lock);
 	now = get_tb();
 	for_each_runnable_thread(i, vcpu, vc) {
+		/*
+		 * It's safe to unlock the vcore in the loop here, because
+		 * for_each_runnable_thread() is safe against removal of
+		 * the vcpu, and the vcore state is VCORE_EXITING here,
+		 * so any vcpus becoming runnable will have their arch.trap
+		 * set to zero and can't actually run in the guest.
+		 */
+		spin_unlock(&vc->lock);
 		/* cancel pending dec exception if dec is positive */
 		if (now < vcpu->arch.dec_expires &&
 		    kvmppc_core_pending_dec(vcpu))
@@ -2614,6 +2614,7 @@ static void post_guest_process(struct kvmppc_vcore *vc, bool is_master)
 		vcpu->arch.ret = ret;
 		vcpu->arch.trap = 0;
 
+		spin_lock(&vc->lock);
 		if (is_kvmppc_resume_guest(vcpu->arch.ret)) {
 			if (vcpu->arch.pending_exceptions)
 				kvmppc_core_prepare_to_enter(vcpu);
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 10/32] KVM: PPC: Book3S HV: Handle hypervisor instruction faults better
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

Currently the code for handling hypervisor instruction page faults
passes 0 for the flags indicating the type of fault, which is OK in
the usual case that the page is not mapped in the partition-scoped
page tables.  However, there are other causes for hypervisor
instruction page faults, such as not being to update a reference
(R) or change (C) bit.  The cause is indicated in bits in HSRR1,
including a bit which indicates that the fault is due to not being
able to write to a page (for example to update an R or C bit).
Not handling these other kinds of faults correctly can lead to a
loop of continual faults without forward progress in the guest.

In order to handle these faults better, this patch constructs a
"DSISR-like" value from the bits which DSISR and SRR1 (for a HISI)
have in common, and passes it to kvmppc_book3s_hv_page_fault() so
that it knows what caused the fault.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/reg.h | 1 +
 arch/powerpc/kvm/book3s_hv.c   | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index e5b314e..6fda746 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -766,6 +766,7 @@
 #define SPRN_HSRR0	0x13A	/* Save/Restore Register 0 */
 #define SPRN_HSRR1	0x13B	/* Save/Restore Register 1 */
 #define   HSRR1_DENORM		0x00100000 /* Denorm exception */
+#define   HSRR1_HISI_WRITE	0x00010000 /* HISI bcs couldn't update mem */
 
 #define SPRN_TBCTL	0x35f	/* PA6T Timebase control register */
 #define   TBCTL_FREEZE		0x0000000000000000ull /* Freeze all tbs */
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 0dda782..3aabbb2 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1188,7 +1188,10 @@ static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		break;
 	case BOOK3S_INTERRUPT_H_INST_STORAGE:
 		vcpu->arch.fault_dar = kvmppc_get_pc(vcpu);
-		vcpu->arch.fault_dsisr = 0;
+		vcpu->arch.fault_dsisr = vcpu->arch.shregs.msr &
+			DSISR_SRR1_MATCH_64S;
+		if (vcpu->arch.shregs.msr & HSRR1_HISI_WRITE)
+			vcpu->arch.fault_dsisr |= DSISR_ISSTORE;
 		r = RESUME_PAGE_FAULT;
 		break;
 	/*
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 09/32] KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guests
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This creates an alternative guest entry/exit path which is used for
radix guests on POWER9 systems when we have indep_threads_mode=Y.  In
these circumstances there is exactly one vcpu per vcore and there is
no coordination required between vcpus or vcores; the vcpu can enter
the guest without needing to synchronize with anything else.

The new fast path is implemented almost entirely in C in book3s_hv.c
and runs with the MMU on until the guest is entered.  On guest exit
we use the existing path until the point where we are committed to
exiting the guest (as distinct from handling an interrupt in the
low-level code and returning to the guest) and we have pulled the
guest context from the XIVE.  At that point we check a flag in the
stack frame to see whether we came in via the old path and the new
path; if we came in via the new path then we go back to C code to do
the rest of the process of saving the guest context and restoring the
host context.

The C code is split into separate functions for handling the
OS-accessible state and the hypervisor state, with the idea that the
latter can be replaced by a hypercall when we implement nested
virtualization.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/asm-prototypes.h |   2 +
 arch/powerpc/include/asm/kvm_ppc.h        |   2 +
 arch/powerpc/kvm/book3s_hv.c              | 425 +++++++++++++++++++++++++++++-
 arch/powerpc/kvm/book3s_hv_ras.c          |   2 +
 arch/powerpc/kvm/book3s_hv_rmhandlers.S   |  95 ++++++-
 arch/powerpc/kvm/book3s_xive.c            |  63 +++++
 6 files changed, 585 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index 0c1a2b0..5c9b00c 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -165,4 +165,6 @@ void kvmhv_load_host_pmu(void);
 void kvmhv_save_guest_pmu(struct kvm_vcpu *vcpu, bool pmu_in_use);
 void kvmhv_load_guest_pmu(struct kvm_vcpu *vcpu);
 
+int __kvmhv_vcpu_entry_p9(struct kvm_vcpu *vcpu);
+
 #endif /* _ASM_POWERPC_ASM_PROTOTYPES_H */
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 83d61b8..245e564 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -585,6 +585,7 @@ extern int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval);
 
 extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq,
 			       int level, bool line_status);
+extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu);
 #else
 static inline int kvmppc_xive_set_xive(struct kvm *kvm, u32 irq, u32 server,
 				       u32 priority) { return -1; }
@@ -607,6 +608,7 @@ static inline int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval) { retur
 
 static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq,
 				      int level, bool line_status) { return -ENODEV; }
+static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { }
 #endif /* CONFIG_KVM_XIVE */
 
 /*
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 0e17593..0dda782 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3080,6 +3080,269 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
 }
 
 /*
+ * Load up hypervisor-mode registers on P9.
+ */
+static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit)
+{
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	s64 hdec;
+	u64 tb, purr, spurr;
+	int trap;
+	unsigned long host_hfscr = mfspr(SPRN_HFSCR);
+	unsigned long host_ciabr = mfspr(SPRN_CIABR);
+	unsigned long host_dawr = mfspr(SPRN_DAWR);
+	unsigned long host_dawrx = mfspr(SPRN_DAWRX);
+	unsigned long host_psscr = mfspr(SPRN_PSSCR);
+	unsigned long host_pidr = mfspr(SPRN_PID);
+
+	hdec = time_limit - mftb();
+	if (hdec < 0)
+		return BOOK3S_INTERRUPT_HV_DECREMENTER;
+	mtspr(SPRN_HDEC, hdec);
+
+	if (vc->tb_offset) {
+		u64 new_tb = mftb() + vc->tb_offset;
+		mtspr(SPRN_TBU40, new_tb);
+		tb = mftb();
+		if ((tb & 0xffffff) < (new_tb & 0xffffff))
+			mtspr(SPRN_TBU40, new_tb + 0x1000000);
+		vc->tb_offset_applied = vc->tb_offset;
+	}
+
+	if (vc->pcr)
+		mtspr(SPRN_PCR, vc->pcr);
+	mtspr(SPRN_DPDES, vc->dpdes);
+	mtspr(SPRN_VTB, vc->vtb);
+
+	local_paca->kvm_hstate.host_purr = mfspr(SPRN_PURR);
+	local_paca->kvm_hstate.host_spurr = mfspr(SPRN_SPURR);
+	mtspr(SPRN_PURR, vcpu->arch.purr);
+	mtspr(SPRN_SPURR, vcpu->arch.spurr);
+
+	if (cpu_has_feature(CPU_FTR_DAWR)) {
+		mtspr(SPRN_DAWR, vcpu->arch.dawr);
+		mtspr(SPRN_DAWRX, vcpu->arch.dawrx);
+	}
+	mtspr(SPRN_CIABR, vcpu->arch.ciabr);
+	mtspr(SPRN_IC, vcpu->arch.ic);
+	mtspr(SPRN_PID, vcpu->arch.pid);
+
+	mtspr(SPRN_PSSCR, vcpu->arch.psscr | PSSCR_EC |
+	      (local_paca->kvm_hstate.fake_suspend << PSSCR_FAKE_SUSPEND_LG));
+
+	mtspr(SPRN_HFSCR, vcpu->arch.hfscr);
+
+	mtspr(SPRN_SPRG0, vcpu->arch.shregs.sprg0);
+	mtspr(SPRN_SPRG1, vcpu->arch.shregs.sprg1);
+	mtspr(SPRN_SPRG2, vcpu->arch.shregs.sprg2);
+	mtspr(SPRN_SPRG3, vcpu->arch.shregs.sprg3);
+
+	mtspr(SPRN_AMOR, ~0UL);
+
+	mtspr(SPRN_LPCR, vc->lpcr);
+	isync();
+
+	kvmppc_xive_push_vcpu(vcpu);
+
+	mtspr(SPRN_SRR0, vcpu->arch.shregs.srr0);
+	mtspr(SPRN_SRR1, vcpu->arch.shregs.srr1);
+
+	trap = __kvmhv_vcpu_entry_p9(vcpu);
+
+	/* Advance host PURR/SPURR by the amount used by guest */
+	purr = mfspr(SPRN_PURR);
+	spurr = mfspr(SPRN_SPURR);
+	mtspr(SPRN_PURR, local_paca->kvm_hstate.host_purr +
+	      purr - vcpu->arch.purr);
+	mtspr(SPRN_SPURR, local_paca->kvm_hstate.host_spurr +
+	      spurr - vcpu->arch.spurr);
+	vcpu->arch.purr = purr;
+	vcpu->arch.spurr = spurr;
+
+	vcpu->arch.ic = mfspr(SPRN_IC);
+	vcpu->arch.pid = mfspr(SPRN_PID);
+	vcpu->arch.psscr = mfspr(SPRN_PSSCR) & PSSCR_GUEST_VIS;
+
+	vcpu->arch.shregs.sprg0 = mfspr(SPRN_SPRG0);
+	vcpu->arch.shregs.sprg1 = mfspr(SPRN_SPRG1);
+	vcpu->arch.shregs.sprg2 = mfspr(SPRN_SPRG2);
+	vcpu->arch.shregs.sprg3 = mfspr(SPRN_SPRG3);
+
+	mtspr(SPRN_PSSCR, host_psscr);
+	mtspr(SPRN_HFSCR, host_hfscr);
+	mtspr(SPRN_CIABR, host_ciabr);
+	mtspr(SPRN_DAWR, host_dawr);
+	mtspr(SPRN_DAWRX, host_dawrx);
+	mtspr(SPRN_PID, host_pidr);
+
+	/*
+	 * Since this is radix, do a eieio; tlbsync; ptesync sequence in
+	 * case we interrupted the guest between a tlbie and a ptesync.
+	 */
+	asm volatile("eieio; tlbsync; ptesync");
+
+	mtspr(SPRN_LPID, vcpu->kvm->arch.host_lpid);	/* restore host LPID */
+	isync();
+
+	vc->dpdes = mfspr(SPRN_DPDES);
+	vc->vtb = mfspr(SPRN_VTB);
+	mtspr(SPRN_DPDES, 0);
+	if (vc->pcr)
+		mtspr(SPRN_PCR, 0);
+
+	if (vc->tb_offset_applied) {
+		u64 new_tb = mftb() - vc->tb_offset_applied;
+		mtspr(SPRN_TBU40, new_tb);
+		tb = mftb();
+		if ((tb & 0xffffff) < (new_tb & 0xffffff))
+			mtspr(SPRN_TBU40, new_tb + 0x1000000);
+		vc->tb_offset_applied = 0;
+	}
+
+	mtspr(SPRN_HDEC, 0x7fffffff);
+	mtspr(SPRN_LPCR, vcpu->kvm->arch.host_lpcr);
+
+	return trap;
+}
+
+/*
+ * Virtual-mode guest entry for POWER9 and later when the host and
+ * guest are both using the radix MMU.  The LPIDR has already been set.
+ */
+int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit)
+{
+	struct kvmppc_vcore *vc = vcpu->arch.vcore;
+	unsigned long host_dscr = mfspr(SPRN_DSCR);
+	unsigned long host_tidr = mfspr(SPRN_TIDR);
+	unsigned long host_iamr = mfspr(SPRN_IAMR);
+	s64 dec;
+	u64 tb;
+	int trap, save_pmu;
+
+	dec = mfspr(SPRN_DEC);
+	tb = mftb();
+	if (dec < 512)
+		return BOOK3S_INTERRUPT_HV_DECREMENTER;
+	local_paca->kvm_hstate.dec_expires = dec + tb;
+	if (local_paca->kvm_hstate.dec_expires < time_limit)
+		time_limit = local_paca->kvm_hstate.dec_expires;
+
+	vcpu->arch.ceded = 0;
+
+	kvmhv_save_host_pmu();		/* saves it to PACA kvm_hstate */
+
+	kvmppc_subcore_enter_guest();
+
+	vc->entry_exit_map = 1;
+	vc->in_guest = 1;
+
+	if (vcpu->arch.vpa.pinned_addr) {
+		struct lppaca *lp = vcpu->arch.vpa.pinned_addr;
+		u32 yield_count = be32_to_cpu(lp->yield_count) + 1;
+		lp->yield_count = cpu_to_be32(yield_count);
+		vcpu->arch.vpa.dirty = 1;
+	}
+
+	if (cpu_has_feature(CPU_FTR_TM) ||
+	    cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST))
+		kvmppc_restore_tm_hv(vcpu, vcpu->arch.shregs.msr, true);
+
+	kvmhv_load_guest_pmu(vcpu);
+
+	msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX);
+	load_fp_state(&vcpu->arch.fp);
+	load_vr_state(&vcpu->arch.vr);
+
+	mtspr(SPRN_DSCR, vcpu->arch.dscr);
+	mtspr(SPRN_IAMR, vcpu->arch.iamr);
+	mtspr(SPRN_PSPB, vcpu->arch.pspb);
+	mtspr(SPRN_FSCR, vcpu->arch.fscr);
+	mtspr(SPRN_TAR, vcpu->arch.tar);
+	mtspr(SPRN_EBBHR, vcpu->arch.ebbhr);
+	mtspr(SPRN_EBBRR, vcpu->arch.ebbrr);
+	mtspr(SPRN_BESCR, vcpu->arch.bescr);
+	mtspr(SPRN_WORT, vcpu->arch.wort);
+	mtspr(SPRN_TIDR, vcpu->arch.tid);
+	mtspr(SPRN_DAR, vcpu->arch.shregs.dar);
+	mtspr(SPRN_DSISR, vcpu->arch.shregs.dsisr);
+	mtspr(SPRN_AMR, vcpu->arch.amr);
+	mtspr(SPRN_UAMOR, vcpu->arch.uamor);
+
+	if (!(vcpu->arch.ctrl & 1))
+		mtspr(SPRN_CTRLT, mfspr(SPRN_CTRLF) & ~1);
+
+	mtspr(SPRN_DEC, vcpu->arch.dec_expires - mftb());
+
+	if (vcpu->arch.doorbell_request) {
+		vc->dpdes = 1;
+		smp_wmb();
+		vcpu->arch.doorbell_request = 0;
+	}
+
+	trap = kvmhv_load_hv_regs_and_go(vcpu, time_limit);
+
+	vcpu->arch.slb_max = 0;
+	dec = mfspr(SPRN_DEC);
+	tb = mftb();
+	vcpu->arch.dec_expires = dec + tb;
+	vcpu->cpu = -1;
+	vcpu->arch.thread_cpu = -1;
+	vcpu->arch.ctrl = mfspr(SPRN_CTRLF);
+
+	vcpu->arch.iamr = mfspr(SPRN_IAMR);
+	vcpu->arch.pspb = mfspr(SPRN_PSPB);
+	vcpu->arch.fscr = mfspr(SPRN_FSCR);
+	vcpu->arch.tar = mfspr(SPRN_TAR);
+	vcpu->arch.ebbhr = mfspr(SPRN_EBBHR);
+	vcpu->arch.ebbrr = mfspr(SPRN_EBBRR);
+	vcpu->arch.bescr = mfspr(SPRN_BESCR);
+	vcpu->arch.wort = mfspr(SPRN_WORT);
+	vcpu->arch.tid = mfspr(SPRN_TIDR);
+	vcpu->arch.amr = mfspr(SPRN_AMR);
+	vcpu->arch.uamor = mfspr(SPRN_UAMOR);
+	vcpu->arch.dscr = mfspr(SPRN_DSCR);
+
+	mtspr(SPRN_PSPB, 0);
+	mtspr(SPRN_WORT, 0);
+	mtspr(SPRN_AMR, 0);
+	mtspr(SPRN_UAMOR, 0);
+	mtspr(SPRN_DSCR, host_dscr);
+	mtspr(SPRN_TIDR, host_tidr);
+	mtspr(SPRN_IAMR, host_iamr);
+	mtspr(SPRN_PSPB, 0);
+
+	msr_check_and_set(MSR_FP | MSR_VEC | MSR_VSX);
+	store_fp_state(&vcpu->arch.fp);
+	store_vr_state(&vcpu->arch.vr);
+
+	if (cpu_has_feature(CPU_FTR_TM) ||
+	    cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST))
+		kvmppc_save_tm_hv(vcpu, vcpu->arch.shregs.msr, true);
+
+	save_pmu = 1;
+	if (vcpu->arch.vpa.pinned_addr) {
+		struct lppaca *lp = vcpu->arch.vpa.pinned_addr;
+		u32 yield_count = be32_to_cpu(lp->yield_count) + 1;
+		lp->yield_count = cpu_to_be32(yield_count);
+		vcpu->arch.vpa.dirty = 1;
+		save_pmu = lp->pmcregs_in_use;
+	}
+
+	kvmhv_save_guest_pmu(vcpu, save_pmu);
+
+	vc->entry_exit_map = 0x101;
+	vc->in_guest = 0;
+
+	mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - mftb());
+
+	kvmhv_load_host_pmu();
+
+	kvmppc_subcore_exit_guest();
+
+	return trap;
+}
+
+/*
  * Wait for some other vcpu thread to execute us, and
  * wake us up when we need to handle something in the host.
  */
@@ -3405,6 +3668,163 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
 	return vcpu->arch.ret;
 }
 
+static int kvmhv_run_single_vcpu(struct kvm_run *kvm_run,
+				 struct kvm_vcpu *vcpu, u64 time_limit)
+{
+	int trap, r, pcpu, pcpu0;
+	int srcu_idx;
+	struct kvmppc_vcore *vc;
+
+	trace_kvmppc_run_vcpu_enter(vcpu);
+
+	kvm_run->exit_reason = 0;
+	vcpu->arch.ret = RESUME_GUEST;
+	vcpu->arch.trap = 0;
+
+	vc = vcpu->arch.vcore;
+	vcpu->arch.ceded = 0;
+	vcpu->arch.run_task = current;
+	vcpu->arch.kvm_run = kvm_run;
+	vcpu->arch.stolen_logged = vcore_stolen_time(vc, mftb());
+	vcpu->arch.state = KVMPPC_VCPU_RUNNABLE;
+	vcpu->arch.busy_preempt = TB_NIL;
+	vcpu->arch.last_inst = KVM_INST_FETCH_FAILED;
+	vc->runnable_threads[0] = vcpu;
+	vc->n_runnable = 1;
+	vc->runner = vcpu;
+
+	/* See if the MMU is ready to go */
+	if (!vcpu->kvm->arch.mmu_ready) {
+		r = kvmhv_setup_mmu(vcpu);
+		if (r) {
+			kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+			kvm_run->fail_entry.
+				hardware_entry_failure_reason = 0;
+			vcpu->arch.ret = r;
+			goto out;
+		}
+	}
+
+	if (need_resched())
+		cond_resched();
+
+	kvmppc_update_vpas(vcpu);
+
+	init_vcore_to_run(vc);
+	vc->preempt_tb = TB_NIL;
+
+	preempt_disable();
+	pcpu = smp_processor_id();
+	vc->pcpu = pcpu;
+	kvmppc_prepare_radix_vcpu(vcpu, pcpu);
+
+	local_irq_disable();
+	hard_irq_disable();
+	if (signal_pending(current))
+		goto sigpend;
+	if (lazy_irq_pending() || need_resched() || !vcpu->kvm->arch.mmu_ready)
+		goto out;
+
+	kvmppc_core_prepare_to_enter(vcpu);
+
+	kvmppc_clear_host_core(pcpu);
+
+	local_paca->kvm_hstate.tid = 0;
+	local_paca->kvm_hstate.napping = 0;
+	local_paca->kvm_hstate.kvm_split_mode = NULL;
+	kvmppc_start_thread(vcpu, vc);
+	kvmppc_create_dtl_entry(vcpu, vc);
+	trace_kvm_guest_enter(vcpu);
+
+	vc->vcore_state = VCORE_RUNNING;
+	trace_kvmppc_run_core(vc, 0);
+
+	mtspr(SPRN_LPID, vc->kvm->arch.lpid);
+	isync();
+
+	/* See comment above in kvmppc_run_core() about this */
+	pcpu0 = pcpu;
+	if (cpu_has_feature(CPU_FTR_ARCH_300))
+		pcpu0 &= ~0x3UL;
+
+	if (cpumask_test_cpu(pcpu0, &vc->kvm->arch.need_tlb_flush)) {
+		radix__local_flush_tlb_lpid_guest(vc->kvm->arch.lpid);
+		/* Clear the bit after the TLB flush */
+		cpumask_clear_cpu(pcpu0, &vc->kvm->arch.need_tlb_flush);
+	}
+
+	trace_hardirqs_on();
+	guest_enter_irqoff();
+
+	srcu_idx = srcu_read_lock(&vc->kvm->srcu);
+
+	this_cpu_disable_ftrace();
+
+	trap = kvmhv_p9_guest_entry(vcpu, time_limit);
+	vcpu->arch.trap = trap;
+
+	this_cpu_enable_ftrace();
+
+	srcu_read_unlock(&vc->kvm->srcu, srcu_idx);
+
+	mtspr(SPRN_LPID, vc->kvm->arch.host_lpid);
+	isync();
+
+	trace_hardirqs_off();
+	set_irq_happened(trap);
+
+	kvmppc_set_host_core(pcpu);
+
+	local_irq_enable();
+	guest_exit();
+	preempt_enable();
+
+	/* cancel pending decrementer exception if DEC is now positive */
+	if (get_tb() < vcpu->arch.dec_expires && kvmppc_core_pending_dec(vcpu))
+		kvmppc_core_dequeue_dec(vcpu);
+
+	trace_kvm_guest_exit(vcpu);
+	r = RESUME_GUEST;
+	if (trap)
+		r = kvmppc_handle_exit_hv(kvm_run, vcpu, current);
+	vcpu->arch.ret = r;
+
+	if (is_kvmppc_resume_guest(r) && vcpu->arch.ceded &&
+	    !kvmppc_vcpu_woken(vcpu)) {
+		kvmppc_set_timer(vcpu);
+		while (vcpu->arch.ceded && !kvmppc_vcpu_woken(vcpu)) {
+			if (signal_pending(current)) {
+				vcpu->stat.signal_exits++;
+				kvm_run->exit_reason = KVM_EXIT_INTR;
+				vcpu->arch.ret = -EINTR;
+				break;
+			}
+			spin_lock(&vc->lock);
+			kvmppc_vcore_blocked(vc);
+			spin_unlock(&vc->lock);
+		}
+	}
+	vcpu->arch.ceded = 0;
+
+	vc->vcore_state = VCORE_INACTIVE;
+	trace_kvmppc_run_core(vc, 1);
+
+ done:
+	kvmppc_remove_runnable(vc, vcpu);
+	trace_kvmppc_run_vcpu_exit(vcpu, kvm_run);
+
+	return vcpu->arch.ret;
+
+ sigpend:
+	vcpu->stat.signal_exits++;
+	kvm_run->exit_reason = KVM_EXIT_INTR;
+	vcpu->arch.ret = -EINTR;
+ out:
+	local_irq_enable();
+	preempt_enable();
+	goto done;
+}
+
 static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
 {
 	int r;
@@ -3480,7 +3900,10 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
 	vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
 
 	do {
-		r = kvmppc_run_vcpu(run, vcpu);
+		if (kvm->arch.threads_indep && kvm_is_radix(kvm))
+			r = kvmhv_run_single_vcpu(run, vcpu, ~(u64)0);
+		else
+			r = kvmppc_run_vcpu(run, vcpu);
 
 		if (run->exit_reason == KVM_EXIT_PAPR_HCALL &&
 		    !(vcpu->arch.shregs.msr & MSR_PR)) {
diff --git a/arch/powerpc/kvm/book3s_hv_ras.c b/arch/powerpc/kvm/book3s_hv_ras.c
index ee564b6..0787f12 100644
--- a/arch/powerpc/kvm/book3s_hv_ras.c
+++ b/arch/powerpc/kvm/book3s_hv_ras.c
@@ -177,6 +177,7 @@ void kvmppc_subcore_enter_guest(void)
 
 	local_paca->sibling_subcore_state->in_guest[subcore_id] = 1;
 }
+EXPORT_SYMBOL_GPL(kvmppc_subcore_enter_guest);
 
 void kvmppc_subcore_exit_guest(void)
 {
@@ -187,6 +188,7 @@ void kvmppc_subcore_exit_guest(void)
 
 	local_paca->sibling_subcore_state->in_guest[subcore_id] = 0;
 }
+EXPORT_SYMBOL_GPL(kvmppc_subcore_exit_guest);
 
 static bool kvmppc_tb_resync_required(void)
 {
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 67a847f..2abc336 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -47,8 +47,9 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 #define NAPPING_NOVCPU	2
 
 /* Stack frame offsets for kvmppc_hv_entry */
-#define SFS			160
+#define SFS			208
 #define STACK_SLOT_TRAP		(SFS-4)
+#define STACK_SLOT_SHORT_PATH	(SFS-8)
 #define STACK_SLOT_TID		(SFS-16)
 #define STACK_SLOT_PSSCR	(SFS-24)
 #define STACK_SLOT_PID		(SFS-32)
@@ -57,6 +58,8 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
 #define STACK_SLOT_DAWR		(SFS-56)
 #define STACK_SLOT_DAWRX	(SFS-64)
 #define STACK_SLOT_HFSCR	(SFS-72)
+/* the following is used by the P9 short path */
+#define STACK_SLOT_NVGPRS	(SFS-152)	/* 18 gprs */
 
 /*
  * Call kvmppc_hv_entry in real mode.
@@ -1020,6 +1023,9 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
 no_xive:
 #endif /* CONFIG_KVM_XICS */
 
+	li	r0, 0
+	stw	r0, STACK_SLOT_SHORT_PATH(r1)
+
 deliver_guest_interrupt:	/* r4 = vcpu, r13 = paca */
 	/* Check if we can deliver an external or decrementer interrupt now */
 	ld	r0, VCPU_PENDING_EXC(r4)
@@ -1034,13 +1040,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	bl	kvmppc_guest_entry_inject_int
 	ld	r4, HSTATE_KVM_VCPU(r13)
 71:
-	ld	r10, VCPU_PC(r4)
-	ld	r11, VCPU_MSR(r4)
 	ld	r6, VCPU_SRR0(r4)
 	ld	r7, VCPU_SRR1(r4)
 	mtspr	SPRN_SRR0, r6
 	mtspr	SPRN_SRR1, r7
 
+fast_guest_entry_c:
+	ld	r10, VCPU_PC(r4)
+	ld	r11, VCPU_MSR(r4)
 	/* r11 = vcpu->arch.msr & ~MSR_HV */
 	rldicl	r11, r11, 63 - MSR_HV_LG, 1
 	rotldi	r11, r11, 1 + MSR_HV_LG
@@ -1117,6 +1124,83 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
 	HRFI_TO_GUEST
 	b	.
 
+/*
+ * Enter the guest on a P9 or later system where we have exactly
+ * one vcpu per vcore and we don't need to go to real mode
+ * (which implies that host and guest are both using radix MMU mode).
+ * r3 = vcpu pointer
+ * Most SPRs and all the VSRs have been loaded already.
+ */
+_GLOBAL(__kvmhv_vcpu_entry_p9)
+EXPORT_SYMBOL_GPL(__kvmhv_vcpu_entry_p9)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+	stdu	r1, -SFS(r1)
+
+	li	r0, 1
+	stw	r0, STACK_SLOT_SHORT_PATH(r1)
+
+	std	r3, HSTATE_KVM_VCPU(r13)
+	mfcr	r4
+	stw	r4, SFS+8(r1)
+
+	std	r1, HSTATE_HOST_R1(r13)
+
+	reg = 14
+	.rept	18
+	std	reg, STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1)
+	reg = reg + 1
+	.endr
+
+	reg = 14
+	.rept	18
+	ld	reg, __VCPU_GPR(reg)(r3)
+	reg = reg + 1
+	.endr
+
+	mfmsr	r10
+	std	r10, HSTATE_HOST_MSR(r13)
+
+	mr	r4, r3
+	b	fast_guest_entry_c
+guest_exit_short_path:
+
+	li	r0, KVM_GUEST_MODE_NONE
+	stb	r0, HSTATE_IN_GUEST(r13)
+
+	reg = 14
+	.rept	18
+	std	reg, __VCPU_GPR(reg)(r9)
+	reg = reg + 1
+	.endr
+
+	reg = 14
+	.rept	18
+	ld	reg, STACK_SLOT_NVGPRS + ((reg - 14) * 8)(r1)
+	reg = reg + 1
+	.endr
+
+	lwz	r4, SFS+8(r1)
+	mtcr	r4
+
+	mr	r3, r12		/* trap number */
+
+	addi	r1, r1, SFS
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
+
+	/* If we are in real mode, do a rfid to get back to the caller */
+	mfmsr	r4
+	andi.	r5, r4, MSR_IR
+	bnelr
+	rldicl	r5, r4, 64 - MSR_TS_S_LG, 62	/* extract TS field */
+	mtspr	SPRN_SRR0, r0
+	ld	r10, HSTATE_HOST_MSR(r13)
+	rldimi	r10, r5, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+	mtspr	SPRN_SRR1, r10
+	RFI_TO_KERNEL
+	b	.
+
 secondary_too_late:
 	li	r12, 0
 	stw	r12, STACK_SLOT_TRAP(r1)
@@ -1377,6 +1461,11 @@ guest_exit_cont:		/* r9 = vcpu, r12 = trap, r13 = paca */
 1:
 #endif /* CONFIG_KVM_XICS */
 
+	/* If we came in through the P9 short path, go back out to C now */
+	lwz	r0, STACK_SLOT_SHORT_PATH(r1)
+	cmpwi	r0, 0
+	bne	guest_exit_short_path
+
 	/* For hash guest, read the guest SLB and save it away */
 	ld	r5, VCPU_KVM(r9)
 	lbz	r0, KVM_RADIX(r5)
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
index 30c2eb7..ad4a370 100644
--- a/arch/powerpc/kvm/book3s_xive.c
+++ b/arch/powerpc/kvm/book3s_xive.c
@@ -62,6 +62,69 @@
 #define XIVE_Q_GAP	2
 
 /*
+ * Push a vcpu's context to the XIVE on guest entry.
+ * This assumes we are in virtual mode (MMU on)
+ */
+void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu)
+{
+	void __iomem *tima = local_paca->kvm_hstate.xive_tima_virt;
+	u64 pq;
+
+	if (!tima)
+		return;
+	eieio();
+	__raw_writeq(vcpu->arch.xive_saved_state.w01, tima + TM_QW1_OS);
+	__raw_writel(vcpu->arch.xive_cam_word, tima + TM_QW1_OS + TM_WORD2);
+	vcpu->arch.xive_pushed = 1;
+	eieio();
+
+	/*
+	 * We clear the irq_pending flag. There is a small chance of a
+	 * race vs. the escalation interrupt happening on another
+	 * processor setting it again, but the only consequence is to
+	 * cause a spurious wakeup on the next H_CEDE, which is not an
+	 * issue.
+	 */
+	vcpu->arch.irq_pending = 0;
+
+	/*
+	 * In single escalation mode, if the escalation interrupt is
+	 * on, we mask it.
+	 */
+	if (vcpu->arch.xive_esc_on) {
+		pq = __raw_readq((void __iomem *)(vcpu->arch.xive_esc_vaddr +
+						  XIVE_ESB_SET_PQ_01));
+		mb();
+
+		/*
+		 * We have a possible subtle race here: The escalation
+		 * interrupt might have fired and be on its way to the
+		 * host queue while we mask it, and if we unmask it
+		 * early enough (re-cede right away), there is a
+		 * theorical possibility that it fires again, thus
+		 * landing in the target queue more than once which is
+		 * a big no-no.
+		 *
+		 * Fortunately, solving this is rather easy. If the
+		 * above load setting PQ to 01 returns a previous
+		 * value where P is set, then we know the escalation
+		 * interrupt is somewhere on its way to the host. In
+		 * that case we simply don't clear the xive_esc_on
+		 * flag below. It will be eventually cleared by the
+		 * handler for the escalation interrupt.
+		 *
+		 * Then, when doing a cede, we check that flag again
+		 * before re-enabling the escalation interrupt, and if
+		 * set, we abort the cede.
+		 */
+		if (!(pq & XIVE_ESB_VAL_P))
+			/* Now P is 0, we can clear the flag */
+			vcpu->arch.xive_esc_on = 0;
+	}
+}
+EXPORT_SYMBOL_GPL(kvmppc_xive_push_vcpu);
+
+/*
  * This is a simple trigger for a generic XIVE IRQ. This must
  * only be called for interrupts that support a trigger page
  */
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 11/32] KVM: PPC: Book3S HV: Add a debugfs file to dump radix mappings
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

This adds a file called 'radix' in the debugfs directory for the
guest, which when read gives all of the valid leaf PTEs in the
partition-scoped radix tree for a radix guest, in human-readable
format.  It is analogous to the existing 'htab' file which dumps
the HPT entries for a HPT guest.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/kvm_book3s_64.h |   1 +
 arch/powerpc/include/asm/kvm_host.h      |   1 +
 arch/powerpc/kvm/book3s_64_mmu_radix.c   | 179 +++++++++++++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv.c             |   2 +
 4 files changed, 183 insertions(+)

diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index dc435a5..af25aaa 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -435,6 +435,7 @@ static inline struct kvm_memslots *kvm_memslots_raw(struct kvm *kvm)
 }
 
 extern void kvmppc_mmu_debugfs_init(struct kvm *kvm);
+extern void kvmhv_radix_debugfs_init(struct kvm *kvm);
 
 extern void kvmhv_rm_send_ipi(int cpu);
 
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 3cd0b9f..a3d4f61 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -291,6 +291,7 @@ struct kvm_arch {
 	u64 process_table;
 	struct dentry *debugfs_dir;
 	struct dentry *htab_dentry;
+	struct dentry *radix_dentry;
 	struct kvm_resize_hpt *resize_hpt; /* protected by kvm->lock */
 #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index 933c574..71951b5 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -10,6 +10,9 @@
 #include <linux/string.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/debugfs.h>
 
 #include <asm/kvm_ppc.h>
 #include <asm/kvm_book3s.h>
@@ -853,6 +856,182 @@ static void pmd_ctor(void *addr)
 	memset(addr, 0, RADIX_PMD_TABLE_SIZE);
 }
 
+struct debugfs_radix_state {
+	struct kvm	*kvm;
+	struct mutex	mutex;
+	unsigned long	gpa;
+	int		chars_left;
+	int		buf_index;
+	char		buf[128];
+	u8		hdr;
+};
+
+static int debugfs_radix_open(struct inode *inode, struct file *file)
+{
+	struct kvm *kvm = inode->i_private;
+	struct debugfs_radix_state *p;
+
+	p = kzalloc(sizeof(*p), GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+
+	kvm_get_kvm(kvm);
+	p->kvm = kvm;
+	mutex_init(&p->mutex);
+	file->private_data = p;
+
+	return nonseekable_open(inode, file);
+}
+
+static int debugfs_radix_release(struct inode *inode, struct file *file)
+{
+	struct debugfs_radix_state *p = file->private_data;
+
+	kvm_put_kvm(p->kvm);
+	kfree(p);
+	return 0;
+}
+
+static ssize_t debugfs_radix_read(struct file *file, char __user *buf,
+				 size_t len, loff_t *ppos)
+{
+	struct debugfs_radix_state *p = file->private_data;
+	ssize_t ret, r;
+	unsigned long n;
+	struct kvm *kvm;
+	unsigned long gpa;
+	pgd_t *pgt;
+	pgd_t pgd, *pgdp;
+	pud_t pud, *pudp;
+	pmd_t pmd, *pmdp;
+	pte_t *ptep;
+	int shift;
+	unsigned long pte;
+
+	kvm = p->kvm;
+	if (!kvm_is_radix(kvm))
+		return 0;
+
+	ret = mutex_lock_interruptible(&p->mutex);
+	if (ret)
+		return ret;
+
+	if (p->chars_left) {
+		n = p->chars_left;
+		if (n > len)
+			n = len;
+		r = copy_to_user(buf, p->buf + p->buf_index, n);
+		n -= r;
+		p->chars_left -= n;
+		p->buf_index += n;
+		buf += n;
+		len -= n;
+		ret = n;
+		if (r) {
+			if (!n)
+				ret = -EFAULT;
+			goto out;
+		}
+	}
+
+	gpa = p->gpa;
+	pgt = kvm->arch.pgtable;
+	while (len != 0 && gpa < RADIX_PGTABLE_RANGE) {
+		if (!p->hdr) {
+			n = scnprintf(p->buf, sizeof(p->buf),
+				      "pgdir: %lx\n", (unsigned long)pgt);
+			p->hdr = 1;
+			goto copy;
+		}
+
+		pgdp = pgt + pgd_index(gpa);
+		pgd = READ_ONCE(*pgdp);
+		if (!(pgd_val(pgd) & _PAGE_PRESENT)) {
+			gpa = (gpa & PGDIR_MASK) + PGDIR_SIZE;
+			continue;
+		}
+
+		pudp = pud_offset(&pgd, gpa);
+		pud = READ_ONCE(*pudp);
+		if (!(pud_val(pud) & _PAGE_PRESENT)) {
+			gpa = (gpa & PUD_MASK) + PUD_SIZE;
+			continue;
+		}
+		if (pud_val(pud) & _PAGE_PTE) {
+			pte = pud_val(pud);
+			shift = PUD_SHIFT;
+			goto leaf;
+		}
+
+		pmdp = pmd_offset(&pud, gpa);
+		pmd = READ_ONCE(*pmdp);
+		if (!(pmd_val(pmd) & _PAGE_PRESENT)) {
+			gpa = (gpa & PMD_MASK) + PMD_SIZE;
+			continue;
+		}
+		if (pmd_val(pmd) & _PAGE_PTE) {
+			pte = pmd_val(pmd);
+			shift = PMD_SHIFT;
+			goto leaf;
+		}
+
+		ptep = pte_offset_kernel(&pmd, gpa);
+		pte = pte_val(READ_ONCE(*ptep));
+		if (!(pte & _PAGE_PRESENT)) {
+			gpa += PAGE_SIZE;
+			continue;
+		}
+		shift = PAGE_SHIFT;
+	leaf:
+		n = scnprintf(p->buf, sizeof(p->buf),
+			      " %lx: %lx %d\n", gpa, pte, shift);
+		gpa += 1ul << shift;
+	copy:
+		p->chars_left = n;
+		if (n > len)
+			n = len;
+		r = copy_to_user(buf, p->buf, n);
+		n -= r;
+		p->chars_left -= n;
+		p->buf_index = n;
+		buf += n;
+		len -= n;
+		ret += n;
+		if (r) {
+			if (!ret)
+				ret = -EFAULT;
+			break;
+		}
+	}
+	p->gpa = gpa;
+
+ out:
+	mutex_unlock(&p->mutex);
+	return ret;
+}
+
+static ssize_t debugfs_radix_write(struct file *file, const char __user *buf,
+			   size_t len, loff_t *ppos)
+{
+	return -EACCES;
+}
+
+static const struct file_operations debugfs_radix_fops = {
+	.owner	 = THIS_MODULE,
+	.open	 = debugfs_radix_open,
+	.release = debugfs_radix_release,
+	.read	 = debugfs_radix_read,
+	.write	 = debugfs_radix_write,
+	.llseek	 = generic_file_llseek,
+};
+
+void kvmhv_radix_debugfs_init(struct kvm *kvm)
+{
+	kvm->arch.radix_dentry = debugfs_create_file("radix", 0400,
+						     kvm->arch.debugfs_dir, kvm,
+						     &debugfs_radix_fops);
+}
+
 int kvmppc_radix_init(void)
 {
 	unsigned long size = sizeof(void *) << RADIX_PTE_INDEX_SIZE;
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 3aabbb2..aa13728 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4477,6 +4477,8 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm)
 	snprintf(buf, sizeof(buf), "vm%d", current->pid);
 	kvm->arch.debugfs_dir = debugfs_create_dir(buf, kvm_debugfs_dir);
 	kvmppc_mmu_debugfs_init(kvm);
+	if (radix_enabled())
+		kvmhv_radix_debugfs_init(kvm);
 
 	return 0;
 }
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 12/32] KVM: PPC: Use ccr field in pt_regs struct embedded in vcpu struct
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

When the 'regs' field was added to struct kvm_vcpu_arch, the code
was changed to use several of the fields inside regs (e.g., gpr, lr,
etc.) but not the ccr field, because the ccr field in struct pt_regs
is 64 bits on 64-bit platforms, but the cr field in kvm_vcpu_arch is
only 32 bits.  This changes the code to use the regs.ccr field
instead of cr, and changes the assembly code on 64-bit platforms to
use 64-bit loads and stores instead of 32-bit ones.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/kvm_book3s.h    |  4 ++--
 arch/powerpc/include/asm/kvm_book3s_64.h |  4 ++--
 arch/powerpc/include/asm/kvm_booke.h     |  4 ++--
 arch/powerpc/include/asm/kvm_host.h      |  2 --
 arch/powerpc/kernel/asm-offsets.c        |  4 ++--
 arch/powerpc/kvm/book3s_emulate.c        | 12 ++++++------
 arch/powerpc/kvm/book3s_hv.c             |  4 ++--
 arch/powerpc/kvm/book3s_hv_rmhandlers.S  |  4 ++--
 arch/powerpc/kvm/book3s_hv_tm.c          |  6 +++---
 arch/powerpc/kvm/book3s_hv_tm_builtin.c  |  5 +++--
 arch/powerpc/kvm/book3s_pr.c             |  4 ++--
 arch/powerpc/kvm/bookehv_interrupts.S    |  8 ++++----
 arch/powerpc/kvm/emulate_loadstore.c     |  1 -
 13 files changed, 30 insertions(+), 32 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 83a9aa3..dd18d81 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -301,12 +301,12 @@ static inline ulong kvmppc_get_gpr(struct kvm_vcpu *vcpu, int num)
 
 static inline void kvmppc_set_cr(struct kvm_vcpu *vcpu, u32 val)
 {
-	vcpu->arch.cr = val;
+	vcpu->arch.regs.ccr = val;
 }
 
 static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu)
 {
-	return vcpu->arch.cr;
+	return vcpu->arch.regs.ccr;
 }
 
 static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, ulong val)
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index af25aaa..5c0e2d9 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -483,7 +483,7 @@ static inline u64 sanitize_msr(u64 msr)
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 static inline void copy_from_checkpoint(struct kvm_vcpu *vcpu)
 {
-	vcpu->arch.cr  = vcpu->arch.cr_tm;
+	vcpu->arch.regs.ccr  = vcpu->arch.cr_tm;
 	vcpu->arch.regs.xer = vcpu->arch.xer_tm;
 	vcpu->arch.regs.link  = vcpu->arch.lr_tm;
 	vcpu->arch.regs.ctr = vcpu->arch.ctr_tm;
@@ -500,7 +500,7 @@ static inline void copy_from_checkpoint(struct kvm_vcpu *vcpu)
 
 static inline void copy_to_checkpoint(struct kvm_vcpu *vcpu)
 {
-	vcpu->arch.cr_tm  = vcpu->arch.cr;
+	vcpu->arch.cr_tm  = vcpu->arch.regs.ccr;
 	vcpu->arch.xer_tm = vcpu->arch.regs.xer;
 	vcpu->arch.lr_tm  = vcpu->arch.regs.link;
 	vcpu->arch.ctr_tm = vcpu->arch.regs.ctr;
diff --git a/arch/powerpc/include/asm/kvm_booke.h b/arch/powerpc/include/asm/kvm_booke.h
index d513e3e..f0cef62 100644
--- a/arch/powerpc/include/asm/kvm_booke.h
+++ b/arch/powerpc/include/asm/kvm_booke.h
@@ -46,12 +46,12 @@ static inline ulong kvmppc_get_gpr(struct kvm_vcpu *vcpu, int num)
 
 static inline void kvmppc_set_cr(struct kvm_vcpu *vcpu, u32 val)
 {
-	vcpu->arch.cr = val;
+	vcpu->arch.regs.ccr = val;
 }
 
 static inline u32 kvmppc_get_cr(struct kvm_vcpu *vcpu)
 {
-	return vcpu->arch.cr;
+	return vcpu->arch.regs.ccr;
 }
 
 static inline void kvmppc_set_xer(struct kvm_vcpu *vcpu, ulong val)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index a3d4f61..c9cc42f 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -538,8 +538,6 @@ struct kvm_vcpu_arch {
 	ulong tar;
 #endif
 
-	u32 cr;
-
 #ifdef CONFIG_PPC_BOOK3S
 	ulong hflags;
 	ulong guest_owned_ext;
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 89cf155..7c3738d 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -438,7 +438,7 @@ int main(void)
 #ifdef CONFIG_PPC_BOOK3S
 	OFFSET(VCPU_TAR, kvm_vcpu, arch.tar);
 #endif
-	OFFSET(VCPU_CR, kvm_vcpu, arch.cr);
+	OFFSET(VCPU_CR, kvm_vcpu, arch.regs.ccr);
 	OFFSET(VCPU_PC, kvm_vcpu, arch.regs.nip);
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	OFFSET(VCPU_MSR, kvm_vcpu, arch.shregs.msr);
@@ -695,7 +695,7 @@ int main(void)
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
 #else /* CONFIG_PPC_BOOK3S */
-	OFFSET(VCPU_CR, kvm_vcpu, arch.cr);
+	OFFSET(VCPU_CR, kvm_vcpu, arch.regs.ccr);
 	OFFSET(VCPU_XER, kvm_vcpu, arch.regs.xer);
 	OFFSET(VCPU_LR, kvm_vcpu, arch.regs.link);
 	OFFSET(VCPU_CTR, kvm_vcpu, arch.regs.ctr);
diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c
index 36b11c5..2654df2 100644
--- a/arch/powerpc/kvm/book3s_emulate.c
+++ b/arch/powerpc/kvm/book3s_emulate.c
@@ -110,7 +110,7 @@ static inline void kvmppc_copyto_vcpu_tm(struct kvm_vcpu *vcpu)
 	vcpu->arch.ctr_tm = vcpu->arch.regs.ctr;
 	vcpu->arch.tar_tm = vcpu->arch.tar;
 	vcpu->arch.lr_tm = vcpu->arch.regs.link;
-	vcpu->arch.cr_tm = vcpu->arch.cr;
+	vcpu->arch.cr_tm = vcpu->arch.regs.ccr;
 	vcpu->arch.xer_tm = vcpu->arch.regs.xer;
 	vcpu->arch.vrsave_tm = vcpu->arch.vrsave;
 }
@@ -129,7 +129,7 @@ static inline void kvmppc_copyfrom_vcpu_tm(struct kvm_vcpu *vcpu)
 	vcpu->arch.regs.ctr = vcpu->arch.ctr_tm;
 	vcpu->arch.tar = vcpu->arch.tar_tm;
 	vcpu->arch.regs.link = vcpu->arch.lr_tm;
-	vcpu->arch.cr = vcpu->arch.cr_tm;
+	vcpu->arch.regs.ccr = vcpu->arch.cr_tm;
 	vcpu->arch.regs.xer = vcpu->arch.xer_tm;
 	vcpu->arch.vrsave = vcpu->arch.vrsave_tm;
 }
@@ -141,7 +141,7 @@ static void kvmppc_emulate_treclaim(struct kvm_vcpu *vcpu, int ra_val)
 	uint64_t texasr;
 
 	/* CR0 = 0 | MSR[TS] | 0 */
-	vcpu->arch.cr = (vcpu->arch.cr & ~(CR0_MASK << CR0_SHIFT)) |
+	vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & ~(CR0_MASK << CR0_SHIFT)) |
 		(((guest_msr & MSR_TS_MASK) >> (MSR_TS_S_LG - 1))
 		 << CR0_SHIFT);
 
@@ -220,7 +220,7 @@ void kvmppc_emulate_tabort(struct kvm_vcpu *vcpu, int ra_val)
 	tm_abort(ra_val);
 
 	/* CR0 = 0 | MSR[TS] | 0 */
-	vcpu->arch.cr = (vcpu->arch.cr & ~(CR0_MASK << CR0_SHIFT)) |
+	vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & ~(CR0_MASK << CR0_SHIFT)) |
 		(((guest_msr & MSR_TS_MASK) >> (MSR_TS_S_LG - 1))
 		 << CR0_SHIFT);
 
@@ -494,8 +494,8 @@ int kvmppc_core_emulate_op_pr(struct kvm_run *run, struct kvm_vcpu *vcpu,
 
 			if (!(kvmppc_get_msr(vcpu) & MSR_PR)) {
 				preempt_disable();
-				vcpu->arch.cr = (CR0_TBEGIN_FAILURE |
-				  (vcpu->arch.cr & ~(CR0_MASK << CR0_SHIFT)));
+				vcpu->arch.regs.ccr = (CR0_TBEGIN_FAILURE |
+				  (vcpu->arch.regs.ccr & ~(CR0_MASK << CR0_SHIFT)));
 
 				vcpu->arch.texasr = (TEXASR_FS | TEXASR_EXACT |
 					(((u64)(TM_CAUSE_EMULATE | TM_CAUSE_PERSISTENT))
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index aa13728..01a0532 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -410,8 +410,8 @@ static void kvmppc_dump_regs(struct kvm_vcpu *vcpu)
 	       vcpu->arch.shregs.sprg0, vcpu->arch.shregs.sprg1);
 	pr_err("sprg2 = %.16llx sprg3 = %.16llx\n",
 	       vcpu->arch.shregs.sprg2, vcpu->arch.shregs.sprg3);
-	pr_err("cr = %.8x  xer = %.16lx  dsisr = %.8x\n",
-	       vcpu->arch.cr, vcpu->arch.regs.xer, vcpu->arch.shregs.dsisr);
+	pr_err("cr = %.8lx  xer = %.16lx  dsisr = %.8x\n",
+	       vcpu->arch.regs.ccr, vcpu->arch.regs.xer, vcpu->arch.shregs.dsisr);
 	pr_err("dar = %.16llx\n", vcpu->arch.shregs.dar);
 	pr_err("fault dar = %.16lx dsisr = %.8x\n",
 	       vcpu->arch.fault_dar, vcpu->arch.fault_dsisr);
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 2abc336..83efc13 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -1092,7 +1092,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 
 	ld	r5, VCPU_LR(r4)
-	lwz	r6, VCPU_CR(r4)
+	ld	r6, VCPU_CR(r4)
 	mtlr	r5
 	mtcr	r6
 
@@ -1280,7 +1280,7 @@ kvmppc_interrupt_hv:
 	std	r3, VCPU_GPR(R12)(r9)
 	/* CR is in the high half of r12 */
 	srdi	r4, r12, 32
-	stw	r4, VCPU_CR(r9)
+	std	r4, VCPU_CR(r9)
 BEGIN_FTR_SECTION
 	ld	r3, HSTATE_CFAR(r13)
 	std	r3, VCPU_CFAR(r9)
diff --git a/arch/powerpc/kvm/book3s_hv_tm.c b/arch/powerpc/kvm/book3s_hv_tm.c
index 0082850..888e260 100644
--- a/arch/powerpc/kvm/book3s_hv_tm.c
+++ b/arch/powerpc/kvm/book3s_hv_tm.c
@@ -130,7 +130,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu)
 			return RESUME_GUEST;
 		}
 		/* Set CR0 to indicate previous transactional state */
-		vcpu->arch.cr = (vcpu->arch.cr & 0x0fffffff) |
+		vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
 			(((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 28);
 		/* L=1 => tresume, L=0 => tsuspend */
 		if (instr & (1 << 21)) {
@@ -174,7 +174,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu)
 		copy_from_checkpoint(vcpu);
 
 		/* Set CR0 to indicate previous transactional state */
-		vcpu->arch.cr = (vcpu->arch.cr & 0x0fffffff) |
+		vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
 			(((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 28);
 		vcpu->arch.shregs.msr &= ~MSR_TS_MASK;
 		return RESUME_GUEST;
@@ -204,7 +204,7 @@ int kvmhv_p9_tm_emulation(struct kvm_vcpu *vcpu)
 		copy_to_checkpoint(vcpu);
 
 		/* Set CR0 to indicate previous transactional state */
-		vcpu->arch.cr = (vcpu->arch.cr & 0x0fffffff) |
+		vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
 			(((msr & MSR_TS_MASK) >> MSR_TS_S_LG) << 28);
 		vcpu->arch.shregs.msr = msr | MSR_TS_S;
 		return RESUME_GUEST;
diff --git a/arch/powerpc/kvm/book3s_hv_tm_builtin.c b/arch/powerpc/kvm/book3s_hv_tm_builtin.c
index b2c7c6f..3cf5863 100644
--- a/arch/powerpc/kvm/book3s_hv_tm_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_tm_builtin.c
@@ -89,7 +89,8 @@ int kvmhv_p9_tm_emulation_early(struct kvm_vcpu *vcpu)
 		if (instr & (1 << 21))
 			vcpu->arch.shregs.msr = (msr & ~MSR_TS_MASK) | MSR_TS_T;
 		/* Set CR0 to 0b0010 */
-		vcpu->arch.cr = (vcpu->arch.cr & 0x0fffffff) | 0x20000000;
+		vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) |
+			0x20000000;
 		return 1;
 	}
 
@@ -105,5 +106,5 @@ void kvmhv_emulate_tm_rollback(struct kvm_vcpu *vcpu)
 	vcpu->arch.shregs.msr &= ~MSR_TS_MASK;	/* go to N state */
 	vcpu->arch.regs.nip = vcpu->arch.tfhar;
 	copy_from_checkpoint(vcpu);
-	vcpu->arch.cr = (vcpu->arch.cr & 0x0fffffff) | 0xa0000000;
+	vcpu->arch.regs.ccr = (vcpu->arch.regs.ccr & 0x0fffffff) | 0xa0000000;
 }
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index 059683e4..4efd65d 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -167,7 +167,7 @@ void kvmppc_copy_to_svcpu(struct kvm_vcpu *vcpu)
 	svcpu->gpr[11] = vcpu->arch.regs.gpr[11];
 	svcpu->gpr[12] = vcpu->arch.regs.gpr[12];
 	svcpu->gpr[13] = vcpu->arch.regs.gpr[13];
-	svcpu->cr  = vcpu->arch.cr;
+	svcpu->cr  = vcpu->arch.regs.ccr;
 	svcpu->xer = vcpu->arch.regs.xer;
 	svcpu->ctr = vcpu->arch.regs.ctr;
 	svcpu->lr  = vcpu->arch.regs.link;
@@ -249,7 +249,7 @@ void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu)
 	vcpu->arch.regs.gpr[11] = svcpu->gpr[11];
 	vcpu->arch.regs.gpr[12] = svcpu->gpr[12];
 	vcpu->arch.regs.gpr[13] = svcpu->gpr[13];
-	vcpu->arch.cr  = svcpu->cr;
+	vcpu->arch.regs.ccr  = svcpu->cr;
 	vcpu->arch.regs.xer = svcpu->xer;
 	vcpu->arch.regs.ctr = svcpu->ctr;
 	vcpu->arch.regs.link  = svcpu->lr;
diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S
index 81bd8a07..051af7d 100644
--- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -182,7 +182,7 @@
 	 */
 	PPC_LL	r4, PACACURRENT(r13)
 	PPC_LL	r4, (THREAD + THREAD_KVM_VCPU)(r4)
-	stw	r10, VCPU_CR(r4)
+	PPC_STL	r10, VCPU_CR(r4)
 	PPC_STL r11, VCPU_GPR(R4)(r4)
 	PPC_STL	r5, VCPU_GPR(R5)(r4)
 	PPC_STL	r6, VCPU_GPR(R6)(r4)
@@ -292,7 +292,7 @@ _GLOBAL(kvmppc_handler_\intno\()_\srr1)
 	PPC_STL	r4, VCPU_GPR(R4)(r11)
 	PPC_LL	r4, THREAD_NORMSAVE(0)(r10)
 	PPC_STL	r5, VCPU_GPR(R5)(r11)
-	stw	r13, VCPU_CR(r11)
+	PPC_STL	r13, VCPU_CR(r11)
 	mfspr	r5, \srr0
 	PPC_STL	r3, VCPU_GPR(R10)(r11)
 	PPC_LL	r3, THREAD_NORMSAVE(2)(r10)
@@ -319,7 +319,7 @@ _GLOBAL(kvmppc_handler_\intno\()_\srr1)
 	PPC_STL	r4, VCPU_GPR(R4)(r11)
 	PPC_LL	r4, GPR9(r8)
 	PPC_STL	r5, VCPU_GPR(R5)(r11)
-	stw	r9, VCPU_CR(r11)
+	PPC_STL	r9, VCPU_CR(r11)
 	mfspr	r5, \srr0
 	PPC_STL	r3, VCPU_GPR(R8)(r11)
 	PPC_LL	r3, GPR10(r8)
@@ -643,7 +643,7 @@ lightweight_exit:
 	PPC_LL	r3, VCPU_LR(r4)
 	PPC_LL	r5, VCPU_XER(r4)
 	PPC_LL	r6, VCPU_CTR(r4)
-	lwz	r7, VCPU_CR(r4)
+	PPC_LL	r7, VCPU_CR(r4)
 	PPC_LL	r8, VCPU_PC(r4)
 	PPC_LD(r9, VCPU_SHARED_MSR, r11)
 	PPC_LL	r0, VCPU_GPR(R0)(r4)
diff --git a/arch/powerpc/kvm/emulate_loadstore.c b/arch/powerpc/kvm/emulate_loadstore.c
index 75dce1e..f91b130 100644
--- a/arch/powerpc/kvm/emulate_loadstore.c
+++ b/arch/powerpc/kvm/emulate_loadstore.c
@@ -117,7 +117,6 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 
 	emulated = EMULATE_FAIL;
 	vcpu->arch.regs.msr = vcpu->arch.shared->msr;
-	vcpu->arch.regs.ccr = vcpu->arch.cr;
 	if (analyse_instr(&op, &vcpu->arch.regs, inst) == 0) {
 		int type = op.type & INSTR_TYPE_MASK;
 		int size = GETSIZE(op.type);
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 13/32] KVM: PPC: Book3S HV: Clear partition table entry on vm teardown
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

When destroying a VM we return the LPID to the pool, however we never
zero the partition table entry. This is instead done when we reallocate
the LPID.

Zero the partition table entry on VM teardown before returning the LPID
to the pool. This means if we were running as a nested hypervisor the
real hypervisor could use this to determine when it can free resources.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kvm/book3s_hv.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 01a0532..ca0e4f4 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4501,13 +4501,19 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
 
 	kvmppc_free_vcores(kvm);
 
-	kvmppc_free_lpid(kvm->arch.lpid);
 
 	if (kvm_is_radix(kvm))
 		kvmppc_free_radix(kvm);
 	else
 		kvmppc_free_hpt(&kvm->arch.hpt);
 
+	/* Perform global invalidation and return lpid to the pool */
+	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+		kvm->arch.process_table = 0;
+		kvmppc_setup_partition_table(kvm);
+	}
+	kvmppc_free_lpid(kvm->arch.lpid);
+
 	kvmppc_free_pimap(kvm);
 }
 
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 14/32] KVM: PPC: Book3S HV: Make kvmppc_mmu_radix_xlate process/partition table agnostic
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

kvmppc_mmu_radix_xlate() is used to translate an effective address
through the process tables. The process table and partition tables have
identical layout. Exploit this fact to make the kvmppc_mmu_radix_xlate()
function able to translate either an effective address through the
process tables or a guest real address through the partition tables.

[paulus@ozlabs.org - reduced diffs from previous code]

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/include/asm/kvm_book3s.h  |   3 +
 arch/powerpc/kvm/book3s_64_mmu_radix.c | 109 +++++++++++++++++++++++----------
 2 files changed, 78 insertions(+), 34 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index dd18d81..91c9779 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -188,6 +188,9 @@ extern int kvmppc_book3s_hcall_implemented(struct kvm *kvm, unsigned long hc);
 extern int kvmppc_book3s_radix_page_fault(struct kvm_run *run,
 			struct kvm_vcpu *vcpu,
 			unsigned long ea, unsigned long dsisr);
+extern int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
+			struct kvmppc_pte *gpte, u64 table,
+			int table_index, u64 *pte_ret_p);
 extern int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 			struct kvmppc_pte *gpte, bool data, bool iswrite);
 extern int kvmppc_init_vm_radix(struct kvm *kvm);
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index 71951b5..f2976f4 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -29,83 +29,92 @@
  */
 static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 };
 
-int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
-			   struct kvmppc_pte *gpte, bool data, bool iswrite)
+/*
+ * Used to walk a partition or process table radix tree in guest memory
+ * Note: We exploit the fact that a partition table and a process
+ * table have the same layout, a partition-scoped page table and a
+ * process-scoped page table have the same layout, and the 2nd
+ * doubleword of a partition table entry has the same layout as
+ * the PTCR register.
+ */
+int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr,
+				     struct kvmppc_pte *gpte, u64 table,
+				     int table_index, u64 *pte_ret_p)
 {
 	struct kvm *kvm = vcpu->kvm;
-	u32 pid;
 	int ret, level, ps;
-	__be64 prte, rpte;
-	unsigned long ptbl;
-	unsigned long root, pte, index;
+	unsigned long ptbl, root;
 	unsigned long rts, bits, offset;
-	unsigned long gpa;
-	unsigned long proc_tbl_size;
+	unsigned long size, index;
+	struct prtb_entry entry;
+	u64 pte, base, gpa;
+	__be64 rpte;
 
-	/* Work out effective PID */
-	switch (eaddr >> 62) {
-	case 0:
-		pid = vcpu->arch.pid;
-		break;
-	case 3:
-		pid = 0;
-		break;
-	default:
+	if ((table & PRTS_MASK) > 24)
 		return -EINVAL;
-	}
-	proc_tbl_size = 1 << ((kvm->arch.process_table & PRTS_MASK) + 12);
-	if (pid * 16 >= proc_tbl_size)
+	size = 1ul << ((table & PRTS_MASK) + 12);
+
+	/* Is the table big enough to contain this entry? */
+	if ((table_index * sizeof(entry)) >= size)
 		return -EINVAL;
 
-	/* Read partition table to find root of tree for effective PID */
-	ptbl = (kvm->arch.process_table & PRTB_MASK) + (pid * 16);
-	ret = kvm_read_guest(kvm, ptbl, &prte, sizeof(prte));
+	/* Read the table to find the root of the radix tree */
+	ptbl = (table & PRTB_MASK) + (table_index * sizeof(entry));
+	ret = kvm_read_guest(kvm, ptbl, &entry, sizeof(entry));
 	if (ret)
 		return ret;
 
-	root = be64_to_cpu(prte);
+	/* Root is stored in the first double word */
+	root = be64_to_cpu(entry.prtb0);
 	rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) |
 		((root & RTS2_MASK) >> RTS2_SHIFT);
 	bits = root & RPDS_MASK;
-	root = root & RPDB_MASK;
+	base = root & RPDB_MASK;
 
 	offset = rts + 31;
 
-	/* current implementations only support 52-bit space */
+	/* Current implementations only support 52-bit space */
 	if (offset != 52)
 		return -EINVAL;
 
+	/* Walk each level of the radix tree */
 	for (level = 3; level >= 0; --level) {
+		/* Check a valid size */
 		if (level && bits != p9_supported_radix_bits[level])
 			return -EINVAL;
 		if (level == 0 && !(bits == 5 || bits == 9))
 			return -EINVAL;
 		offset -= bits;
 		index = (eaddr >> offset) & ((1UL << bits) - 1);
-		/* check that low bits of page table base are zero */
-		if (root & ((1UL << (bits + 3)) - 1))
+		/* Check that low bits of page table base are zero */
+		if (base & ((1UL << (bits + 3)) - 1))
 			return -EINVAL;
-		ret = kvm_read_guest(kvm, root + index * 8,
+		/* Read the entry from guest memory */
+		ret = kvm_read_guest(kvm, base + (index * sizeof(rpte)),
 				     &rpte, sizeof(rpte));
 		if (ret)
 			return ret;
 		pte = __be64_to_cpu(rpte);
 		if (!(pte & _PAGE_PRESENT))
 			return -ENOENT;
+		/* Check if a leaf entry */
 		if (pte & _PAGE_PTE)
 			break;
-		bits = pte & 0x1f;
-		root = pte & 0x0fffffffffffff00ul;
+		/* Get ready to walk the next level */
+		base = pte & RPDB_MASK;
+		bits = pte & RPDS_MASK;
 	}
-	/* need a leaf at lowest level; 512GB pages not supported */
+
+	/* Need a leaf at lowest level; 512GB pages not supported */
 	if (level < 0 || level == 3)
 		return -EINVAL;
 
-	/* offset is now log base 2 of the page size */
+	/* We found a valid leaf PTE */
+	/* Offset is now log base 2 of the page size */
 	gpa = pte & 0x01fffffffffff000ul;
 	if (gpa & ((1ul << offset) - 1))
 		return -EINVAL;
-	gpa += eaddr & ((1ul << offset) - 1);
+	gpa |= eaddr & ((1ul << offset) - 1);
 	for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps)
 		if (offset == mmu_psize_defs[ps].shift)
 			break;
@@ -118,6 +127,38 @@ int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 	gpte->may_read = !!(pte & _PAGE_READ);
 	gpte->may_write = !!(pte & _PAGE_WRITE);
 	gpte->may_execute = !!(pte & _PAGE_EXEC);
+
+	if (pte_ret_p)
+		*pte_ret_p = pte;
+
+	return 0;
+}
+
+int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
+			   struct kvmppc_pte *gpte, bool data, bool iswrite)
+{
+	u32 pid;
+	u64 pte;
+	int ret;
+
+	/* Work out effective PID */
+	switch (eaddr >> 62) {
+	case 0:
+		pid = vcpu->arch.pid;
+		break;
+	case 3:
+		pid = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = kvmppc_mmu_radix_translate_table(vcpu, eaddr, gpte,
+				vcpu->kvm->arch.process_table, pid, &pte);
+	if (ret)
+		return ret;
+
+	/* Check privilege (applies only to process scoped translations) */
 	if (kvmppc_get_msr(vcpu) & MSR_PR) {
 		if (pte & _PAGE_PRIVILEGED) {
 			gpte->may_read = 0;
-- 
2.7.4


^ permalink raw reply related

* [PATCH v4 15/32] KVM: PPC: Book3S HV: Refactor radix page fault handler
From: Paul Mackerras @ 2018-10-04 11:55 UTC (permalink / raw)
  To: kvm, kvm-ppc; +Cc: linuxppc-dev, David Gibson
In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org>

From: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

The radix page fault handler accounts for all cases, including just
needing to insert a pte.  This breaks it up into separate functions for
the two main cases; setting rc and inserting a pte.

This allows us to make the setting of rc and inserting of a pte
generic for any pgtable, not specific to the one for this guest.

[paulus@ozlabs.org - reduced diffs from previous code]

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
 arch/powerpc/kvm/book3s_64_mmu_radix.c | 210 +++++++++++++++++++--------------
 1 file changed, 123 insertions(+), 87 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index f2976f4..47f2b18 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -400,8 +400,9 @@ static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud,
  */
 #define PTE_BITS_MUST_MATCH (~(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED))
 
-static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
-			     unsigned int level, unsigned long mmu_seq)
+static int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte,
+			     unsigned long gpa, unsigned int level,
+			     unsigned long mmu_seq)
 {
 	pgd_t *pgd;
 	pud_t *pud, *new_pud = NULL;
@@ -410,7 +411,7 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
 	int ret;
 
 	/* Traverse the guest's 2nd-level tree, allocate new levels needed */
-	pgd = kvm->arch.pgtable + pgd_index(gpa);
+	pgd = pgtable + pgd_index(gpa);
 	pud = NULL;
 	if (pgd_present(*pgd))
 		pud = pud_offset(pgd, gpa);
@@ -565,95 +566,49 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
 	return ret;
 }
 
-int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
-				   unsigned long ea, unsigned long dsisr)
+static bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable,
+				    bool writing, unsigned long gpa)
+{
+	unsigned long pgflags;
+	unsigned int shift;
+	pte_t *ptep;
+
+	/*
+	 * Need to set an R or C bit in the 2nd-level tables;
+	 * since we are just helping out the hardware here,
+	 * it is sufficient to do what the hardware does.
+	 */
+	pgflags = _PAGE_ACCESSED;
+	if (writing)
+		pgflags |= _PAGE_DIRTY;
+	/*
+	 * We are walking the secondary (partition-scoped) page table here.
+	 * We can do this without disabling irq because the Linux MM
+	 * subsystem doesn't do THP splits and collapses on this tree.
+	 */
+	ptep = __find_linux_pte(pgtable, gpa, NULL, &shift);
+	if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) {
+		kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift);
+		return true;
+	}
+	return false;
+}
+
+static int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu,
+				unsigned long gpa,
+				struct kvm_memory_slot *memslot,
+				bool writing, bool kvm_ro,
+				pte_t *inserted_pte, unsigned int *levelp)
 {
 	struct kvm *kvm = vcpu->kvm;
-	unsigned long mmu_seq;
-	unsigned long gpa, gfn, hva;
-	struct kvm_memory_slot *memslot;
 	struct page *page = NULL;
-	long ret;
-	bool writing;
+	unsigned long mmu_seq;
+	unsigned long hva, gfn = gpa >> PAGE_SHIFT;
 	bool upgrade_write = false;
 	bool *upgrade_p = &upgrade_write;
 	pte_t pte, *ptep;
-	unsigned long pgflags;
 	unsigned int shift, level;
-
-	/* Check for unusual errors */
-	if (dsisr & DSISR_UNSUPP_MMU) {
-		pr_err("KVM: Got unsupported MMU fault\n");
-		return -EFAULT;
-	}
-	if (dsisr & DSISR_BADACCESS) {
-		/* Reflect to the guest as DSI */
-		pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr);
-		kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
-		return RESUME_GUEST;
-	}
-
-	/* Translate the logical address and get the page */
-	gpa = vcpu->arch.fault_gpa & ~0xfffUL;
-	gpa &= ~0xF000000000000000ul;
-	gfn = gpa >> PAGE_SHIFT;
-	if (!(dsisr & DSISR_PRTABLE_FAULT))
-		gpa |= ea & 0xfff;
-	memslot = gfn_to_memslot(kvm, gfn);
-
-	/* No memslot means it's an emulated MMIO region */
-	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
-		if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS |
-			     DSISR_SET_RC)) {
-			/*
-			 * Bad address in guest page table tree, or other
-			 * unusual error - reflect it to the guest as DSI.
-			 */
-			kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
-			return RESUME_GUEST;
-		}
-		return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
-					      dsisr & DSISR_ISSTORE);
-	}
-
-	writing = (dsisr & DSISR_ISSTORE) != 0;
-	if (memslot->flags & KVM_MEM_READONLY) {
-		if (writing) {
-			/* give the guest a DSI */
-			dsisr = DSISR_ISSTORE | DSISR_PROTFAULT;
-			kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
-			return RESUME_GUEST;
-		}
-		upgrade_p = NULL;
-	}
-
-	if (dsisr & DSISR_SET_RC) {
-		/*
-		 * Need to set an R or C bit in the 2nd-level tables;
-		 * since we are just helping out the hardware here,
-		 * it is sufficient to do what the hardware does.
-		 */
-		pgflags = _PAGE_ACCESSED;
-		if (writing)
-			pgflags |= _PAGE_DIRTY;
-		/*
-		 * We are walking the secondary page table here. We can do this
-		 * without disabling irq.
-		 */
-		spin_lock(&kvm->mmu_lock);
-		ptep = __find_linux_pte(kvm->arch.pgtable,
-					gpa, NULL, &shift);
-		if (ptep && pte_present(*ptep) &&
-		    (!writing || pte_write(*ptep))) {
-			kvmppc_radix_update_pte(kvm, ptep, 0, pgflags,
-						gpa, shift);
-			dsisr &= ~DSISR_SET_RC;
-		}
-		spin_unlock(&kvm->mmu_lock);
-		if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
-			       DSISR_PROTFAULT | DSISR_SET_RC)))
-			return RESUME_GUEST;
-	}
+	int ret;
 
 	/* used to check for invalidations in progress */
 	mmu_seq = kvm->mmu_notifier_seq;
@@ -666,7 +621,7 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	 * is that the page is writable.
 	 */
 	hva = gfn_to_hva_memslot(memslot, gfn);
-	if (upgrade_p && __get_user_pages_fast(hva, 1, 1, &page) == 1) {
+	if (!kvm_ro && __get_user_pages_fast(hva, 1, 1, &page) == 1) {
 		upgrade_write = true;
 	} else {
 		unsigned long pfn;
@@ -724,7 +679,12 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	}
 
 	/* Allocate space in the tree and write the PTE */
-	ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq);
+	ret = kvmppc_create_pte(kvm, kvm->arch.pgtable, pte, gpa, level,
+				mmu_seq);
+	if (inserted_pte)
+		*inserted_pte = pte;
+	if (levelp)
+		*levelp = level;
 
 	if (page) {
 		if (!ret && (pte_val(pte) & _PAGE_WRITE))
@@ -732,6 +692,82 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		put_page(page);
 	}
 
+	return ret;
+}
+
+int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
+				   unsigned long ea, unsigned long dsisr)
+{
+	struct kvm *kvm = vcpu->kvm;
+	unsigned long gpa, gfn;
+	struct kvm_memory_slot *memslot;
+	long ret;
+	bool writing = !!(dsisr & DSISR_ISSTORE);
+	bool kvm_ro = false;
+
+	/* Check for unusual errors */
+	if (dsisr & DSISR_UNSUPP_MMU) {
+		pr_err("KVM: Got unsupported MMU fault\n");
+		return -EFAULT;
+	}
+	if (dsisr & DSISR_BADACCESS) {
+		/* Reflect to the guest as DSI */
+		pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr);
+		kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
+		return RESUME_GUEST;
+	}
+
+	/* Translate the logical address */
+	gpa = vcpu->arch.fault_gpa & ~0xfffUL;
+	gpa &= ~0xF000000000000000ul;
+	gfn = gpa >> PAGE_SHIFT;
+	if (!(dsisr & DSISR_PRTABLE_FAULT))
+		gpa |= ea & 0xfff;
+
+	/* Get the corresponding memslot */
+	memslot = gfn_to_memslot(kvm, gfn);
+
+	/* No memslot means it's an emulated MMIO region */
+	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
+		if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS |
+			     DSISR_SET_RC)) {
+			/*
+			 * Bad address in guest page table tree, or other
+			 * unusual error - reflect it to the guest as DSI.
+			 */
+			kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
+			return RESUME_GUEST;
+		}
+		return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, writing);
+	}
+
+	if (memslot->flags & KVM_MEM_READONLY) {
+		if (writing) {
+			/* give the guest a DSI */
+			kvmppc_core_queue_data_storage(vcpu, ea, DSISR_ISSTORE |
+						       DSISR_PROTFAULT);
+			return RESUME_GUEST;
+		}
+		kvm_ro = true;
+	}
+
+	/* Failed to set the reference/change bits */
+	if (dsisr & DSISR_SET_RC) {
+		spin_lock(&kvm->mmu_lock);
+		if (kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable,
+					    writing, gpa))
+			dsisr &= ~DSISR_SET_RC;
+		spin_unlock(&kvm->mmu_lock);
+
+		if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE |
+			       DSISR_PROTFAULT | DSISR_SET_RC)))
+			return RESUME_GUEST;
+	}
+
+	/* Try to insert a pte */
+	ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, writing,
+					     kvm_ro, NULL, NULL);
+
 	if (ret == 0 || ret == -EAGAIN)
 		ret = RESUME_GUEST;
 	return ret;
-- 
2.7.4


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