[PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[Vaibhav Jain]

On nestedv2 the L1 converts a pending doorbell into guest DPDES state at
the top of kvmhv_vcpu_entry_nestedv2() and immediately forgets about it:

	if (vcpu->arch.doorbell_request) {
		vcpu->arch.doorbell_request = 0;
		kvmppc_set_dpdes(vcpu, 1);
	}

Clearing 'doorbell_request' at this point assumes that handing DPDES to the
L0 is equivalent to the L2 having taken the doorbell. That is not true, and
the doorbell can be lost in two ways:

  - The block runs before the lazy_irq_pending() check, so the doorbell is
    consumed even on the path that returns 0 without ever calling
    H_GUEST_RUN_VCPU.

  - DPDES stays pending in the L2 until it is actually delivered. The L2
    may exit for an unrelated reason (hcall, page fault, HDEC) with the
    doorbell still set, typically because it was running with MSR[EE]=0.
    Nothing reloads DPDES afterwards, so the L1 never learns this.

Once 'doorbell_request' has been cleared, the L1 has no record of the
pending doorbell. kvmppc_doorbell_pending() returns false, so
kvmppc_read_dpdes() reports the target thread as idle when a sibling vCPU
emulates 'mfspr DPDES', and the vCPU can be treated as having no work
pending and blocked. From the L2's point of view the doorbell is silently
lost, which shows up as an SMT guest hanging on a doorbell-based IPI.

Fix this by making 'doorbell_request' track the L2's DPDES rather than
being consumed by entry:

  - inject DPDES after the early-return paths and before
    kvmhv_nestedv2_flush_vcpu() serializes it into the vcpu run input
    buffer, and no longer clear 'doorbell_request' there,

  - after H_GUEST_RUN_VCPU, reload DPDES from the L0. The run output only
    carries the state the L0 chose to return and the 'valids' bitmap is
    zeroed on exit, so an explicit kvmhv_nestedv2_cached_reload() is
    needed to see the L2's current value,

  - if DPDES is still set the doorbell was not delivered, so keep
    'doorbell_request' pending so that it is re-injected on the next
    entry; otherwise clear it.

This keeps a pending doorbell visible to the L1 for as long as the L2 has
not consumed it, so vCPU wakeup and DPDES emulation on sibling vCPUs stay
consistent with the L2's actual state.

Fixes: 54ec2bd9e017 ("KVM: PPC: Book3S HV nestedv2: Fix doorbell emulation")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Assisted-by: Claude:Opus-5
---
 arch/powerpc/kvm/book3s_hv.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 61dbeea317f3..40f8717b8a7d 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -15,6 +15,7 @@
  * by Alexander Graf <agraf@suse.de>.
  */
 
+#include "asm/guest-state-buffer.h"
 #include <linux/kvm_host.h>
 #include <linux/kernel.h>
 #include <linux/err.h>
@@ -4253,11 +4254,6 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
 	int trap;
 	long rc;
 
-	if (vcpu->arch.doorbell_request) {
-		vcpu->arch.doorbell_request = 0;
-		kvmppc_set_dpdes(vcpu, 1);
-	}
-
 	io = &vcpu->arch.nestedv2_io;
 
 	msr = mfmsr();
@@ -4265,6 +4261,9 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
 	if (lazy_irq_pending())
 		return 0;
 
+	if (vcpu->arch.doorbell_request)
+		kvmppc_set_dpdes(vcpu, 1);
+
 	rc = kvmhv_nestedv2_flush_vcpu(vcpu, time_limit);
 	if (rc < 0)
 		return -EINVAL;
@@ -4296,6 +4295,17 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
 	if (rc < 0)
 		return -EINVAL;
 
+	/* Check if privileged door bell was requested and handled */
+	if (vcpu->arch.vcore->dpdes) {
+		kvmhv_nestedv2_cached_reload(vcpu, KVMPPC_GSID_DPDES);
+		if (vcpu->arch.vcore->dpdes)
+			vcpu->arch.doorbell_request |= vcpu->arch.vcore->dpdes;
+		else
+			cpu->arch.doorbell_request = 0;
+	} else {
+		vcpu->arch.doorbell_request = 0;
+	}
+
 	timer_rearm_host_dec(*tb);
 
 	/* Record context switch and guest_run_time data */
-- 
2.55.0

Re: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [High] Concurrent doorbell requests from sibling vCPUs are silently lost due to unconditional clearing of `doorbell_request` on exit.
- [Low] Typo in variable name `cpu` instead of `vcpu` leads to an undeclared identifier and build failure.
--

--- Patch [1]: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry ---
commit efc59a0f35293530907029b05624f01523b4f3ea
Author: Vaibhav Jain <vaibhav@linux.ibm.com>

KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

This patch changes how pending doorbells are tracked during nestedv2 entry.
Instead of unconditionally consuming the doorbell on entry, it tracks the
L2's DPDES state and only clears the request if it was actually handled by
the L2.

Fixes: 54ec2bd9e017 ("KVM: PPC: Book3S HV nestedv2: Fix doorbell emulation")

> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c

[ ... ]

> @@ -4296,6 +4295,17 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
>  	if (rc < 0)
>  		return -EINVAL;
>  
> +	/* Check if privileged door bell was requested and handled */
> +	if (vcpu->arch.vcore->dpdes) {
> +		kvmhv_nestedv2_cached_reload(vcpu, KVMPPC_GSID_DPDES);
> +		if (vcpu->arch.vcore->dpdes)
> +			vcpu->arch.doorbell_request |= vcpu->arch.vcore->dpdes;
> +		else
> +			cpu->arch.doorbell_request = 0;

[Severity: Low]
Is there a typo in this assignment?

Using cpu instead of vcpu here appears to cause a build failure due to an
undeclared identifier.

> +	} else {
> +		vcpu->arch.doorbell_request = 0;

[Severity: High]
Could this unconditional clear overwrite concurrent doorbell requests from
sibling vCPUs?

If a sibling vCPU executes msgsndp and sets doorbell_request to 1 while the
target vCPU is executing the L2 guest, that update might be lost.

When the target vCPU exits with vcpu->arch.vcore->dpdes == 0, this path
would wipe out any concurrent doorbell_request set by the sibling during the
guest's execution or exit process. Would this cause guest SMT threads to
miss IPIs and hang?

> +	}
> +
>  	timer_rearm_host_dec(*tb);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260803034426.44249-1-vaibhav@linux.ibm.com?part=1

Re: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[Gautam Menghani]

On Mon, Aug 03, 2026 at 09:14:25AM +0530, Vaibhav Jain wrote:
> On nestedv2 the L1 converts a pending doorbell into guest DPDES state at
> the top of kvmhv_vcpu_entry_nestedv2() and immediately forgets about it:
> 
> 	if (vcpu->arch.doorbell_request) {
> 		vcpu->arch.doorbell_request = 0;
> 		kvmppc_set_dpdes(vcpu, 1);
> 	}
> 
> Clearing 'doorbell_request' at this point assumes that handing DPDES to the
> L0 is equivalent to the L2 having taken the doorbell. That is not true, and
> the doorbell can be lost in two ways:
> 
>   - The block runs before the lazy_irq_pending() check, so the doorbell is
>     consumed even on the path that returns 0 without ever calling
>     H_GUEST_RUN_VCPU.
> 
>   - DPDES stays pending in the L2 until it is actually delivered. The L2
>     may exit for an unrelated reason (hcall, page fault, HDEC) with the
>     doorbell still set, typically because it was running with MSR[EE]=0.
>     Nothing reloads DPDES afterwards, so the L1 never learns this.
> 
> Once 'doorbell_request' has been cleared, the L1 has no record of the
> pending doorbell. kvmppc_doorbell_pending() returns false, so
> kvmppc_read_dpdes() reports the target thread as idle when a sibling vCPU
> emulates 'mfspr DPDES', and the vCPU can be treated as having no work
> pending and blocked. From the L2's point of view the doorbell is silently
> lost, which shows up as an SMT guest hanging on a doorbell-based IPI.
> 
> Fix this by making 'doorbell_request' track the L2's DPDES rather than
> being consumed by entry:
> 
>   - inject DPDES after the early-return paths and before
>     kvmhv_nestedv2_flush_vcpu() serializes it into the vcpu run input
>     buffer, and no longer clear 'doorbell_request' there,
> 
>   - after H_GUEST_RUN_VCPU, reload DPDES from the L0. The run output only
>     carries the state the L0 chose to return and the 'valids' bitmap is
>     zeroed on exit, so an explicit kvmhv_nestedv2_cached_reload() is
>     needed to see the L2's current value,
> 
>   - if DPDES is still set the doorbell was not delivered, so keep
>     'doorbell_request' pending so that it is re-injected on the next
>     entry; otherwise clear it.
> 
> This keeps a pending doorbell visible to the L1 for as long as the L2 has
> not consumed it, so vCPU wakeup and DPDES emulation on sibling vCPUs stay
> consistent with the L2's actual state.
> 
> Fixes: 54ec2bd9e017 ("KVM: PPC: Book3S HV nestedv2: Fix doorbell emulation")
> Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
> Assisted-by: Claude:Opus-5
> ---
>  arch/powerpc/kvm/book3s_hv.c | 20 +++++++++++++++-----
>  1 file changed, 15 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 61dbeea317f3..40f8717b8a7d 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -15,6 +15,7 @@
>   * by Alexander Graf <agraf@suse.de>.
>   */
>  
> +#include "asm/guest-state-buffer.h"
>  #include <linux/kvm_host.h>
>  #include <linux/kernel.h>
>  #include <linux/err.h>
> @@ -4253,11 +4254,6 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
>  	int trap;
>  	long rc;
>  
> -	if (vcpu->arch.doorbell_request) {
> -		vcpu->arch.doorbell_request = 0;
> -		kvmppc_set_dpdes(vcpu, 1);
> -	}
> -
>  	io = &vcpu->arch.nestedv2_io;
>  
>  	msr = mfmsr();
> @@ -4265,6 +4261,9 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
>  	if (lazy_irq_pending())
>  		return 0;
>  
> +	if (vcpu->arch.doorbell_request)
> +		kvmppc_set_dpdes(vcpu, 1);
> +
>  	rc = kvmhv_nestedv2_flush_vcpu(vcpu, time_limit);
>  	if (rc < 0)
>  		return -EINVAL;
> @@ -4296,6 +4295,17 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
>  	if (rc < 0)
>  		return -EINVAL;
>  
> +	/* Check if privileged door bell was requested and handled */
> +	if (vcpu->arch.vcore->dpdes) {
> +		kvmhv_nestedv2_cached_reload(vcpu, KVMPPC_GSID_DPDES);
> +		if (vcpu->arch.vcore->dpdes)
> +			vcpu->arch.doorbell_request |= vcpu->arch.vcore->dpdes;
> +		else
> +			cpu->arch.doorbell_request = 0;

This is a compile error, should be "vcpu->"


> +	} else {
> +		vcpu->arch.doorbell_request = 0;
> +	}
> +

I think this entire block after vcpu exit can be reduced to just

    if (vcpu->arch.doorbell_request)
        vcpu->arch.doorbell_request = kvmppc_get_dpdes(vcpu);


- Gautam

Re: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[Gautam Menghani]

On Mon, Aug 10, 2026 at 04:54:18PM +0530, Gautam Menghani wrote:
> On Mon, Aug 03, 2026 at 09:14:25AM +0530, Vaibhav Jain wrote:
> > On nestedv2 the L1 converts a pending doorbell into guest DPDES state at
> > the top of kvmhv_vcpu_entry_nestedv2() and immediately forgets about it:
> > 
> > 	if (vcpu->arch.doorbell_request) {
> > 		vcpu->arch.doorbell_request = 0;
> > 		kvmppc_set_dpdes(vcpu, 1);
> > 	}
> > 
> > Clearing 'doorbell_request' at this point assumes that handing DPDES to the
> > L0 is equivalent to the L2 having taken the doorbell. That is not true, and
> > the doorbell can be lost in two ways:
> > 
> >   - The block runs before the lazy_irq_pending() check, so the doorbell is
> >     consumed even on the path that returns 0 without ever calling
> >     H_GUEST_RUN_VCPU.
> > 
> >   - DPDES stays pending in the L2 until it is actually delivered. The L2
> >     may exit for an unrelated reason (hcall, page fault, HDEC) with the
> >     doorbell still set, typically because it was running with MSR[EE]=0.
> >     Nothing reloads DPDES afterwards, so the L1 never learns this.
> > 
> > Once 'doorbell_request' has been cleared, the L1 has no record of the
> > pending doorbell. kvmppc_doorbell_pending() returns false, so
> > kvmppc_read_dpdes() reports the target thread as idle when a sibling vCPU
> > emulates 'mfspr DPDES', and the vCPU can be treated as having no work
> > pending and blocked. From the L2's point of view the doorbell is silently
> > lost, which shows up as an SMT guest hanging on a doorbell-based IPI.
> > 
> > Fix this by making 'doorbell_request' track the L2's DPDES rather than
> > being consumed by entry:
> > 
> >   - inject DPDES after the early-return paths and before
> >     kvmhv_nestedv2_flush_vcpu() serializes it into the vcpu run input
> >     buffer, and no longer clear 'doorbell_request' there,
> > 
> >   - after H_GUEST_RUN_VCPU, reload DPDES from the L0. The run output only
> >     carries the state the L0 chose to return and the 'valids' bitmap is
> >     zeroed on exit, so an explicit kvmhv_nestedv2_cached_reload() is
> >     needed to see the L2's current value,
> > 
> >   - if DPDES is still set the doorbell was not delivered, so keep
> >     'doorbell_request' pending so that it is re-injected on the next
> >     entry; otherwise clear it.
> > 
> > This keeps a pending doorbell visible to the L1 for as long as the L2 has
> > not consumed it, so vCPU wakeup and DPDES emulation on sibling vCPUs stay
> > consistent with the L2's actual state.
> > 
> > Fixes: 54ec2bd9e017 ("KVM: PPC: Book3S HV nestedv2: Fix doorbell emulation")
> > Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
> > Assisted-by: Claude:Opus-5
> > ---
> >  arch/powerpc/kvm/book3s_hv.c | 20 +++++++++++++++-----
> >  1 file changed, 15 insertions(+), 5 deletions(-)
> > 
> > diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> > index 61dbeea317f3..40f8717b8a7d 100644
> > --- a/arch/powerpc/kvm/book3s_hv.c
> > +++ b/arch/powerpc/kvm/book3s_hv.c
> > @@ -15,6 +15,7 @@
> >   * by Alexander Graf <agraf@suse.de>.
> >   */
> >  
> > +#include "asm/guest-state-buffer.h"
> >  #include <linux/kvm_host.h>
> >  #include <linux/kernel.h>
> >  #include <linux/err.h>
> > @@ -4253,11 +4254,6 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
> >  	int trap;
> >  	long rc;
> >  
> > -	if (vcpu->arch.doorbell_request) {
> > -		vcpu->arch.doorbell_request = 0;
> > -		kvmppc_set_dpdes(vcpu, 1);
> > -	}
> > -
> >  	io = &vcpu->arch.nestedv2_io;
> >  
> >  	msr = mfmsr();
> > @@ -4265,6 +4261,9 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
> >  	if (lazy_irq_pending())
> >  		return 0;
> >  
> > +	if (vcpu->arch.doorbell_request)
> > +		kvmppc_set_dpdes(vcpu, 1);
> > +
> >  	rc = kvmhv_nestedv2_flush_vcpu(vcpu, time_limit);
> >  	if (rc < 0)
> >  		return -EINVAL;
> > @@ -4296,6 +4295,17 @@ static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
> >  	if (rc < 0)
> >  		return -EINVAL;
> >  
> > +	/* Check if privileged door bell was requested and handled */
> > +	if (vcpu->arch.vcore->dpdes) {
> > +		kvmhv_nestedv2_cached_reload(vcpu, KVMPPC_GSID_DPDES);
> > +		if (vcpu->arch.vcore->dpdes)
> > +			vcpu->arch.doorbell_request |= vcpu->arch.vcore->dpdes;
> > +		else
> > +			cpu->arch.doorbell_request = 0;
> 
> This is a compile error, should be "vcpu->"
> 
> 
> > +	} else {
> > +		vcpu->arch.doorbell_request = 0;
> > +	}
> > +
> 
> I think this entire block after vcpu exit can be reduced to just
> 
>     if (vcpu->arch.doorbell_request)
>         vcpu->arch.doorbell_request = kvmppc_get_dpdes(vcpu);
> 

Gave this a bit more thought - this can miss the doorbell that was sent
to this vcpu while the vcpu was running. I think the below code should
work fine:

     if (vcpu->arch.doorbell_request) {
             vcpu->arch.doorbell_request = 0;
             kvmppc_set_dpdes(vcpu, 1);
     }

     rc = plpar_guest_run_vcpu(...);

    /* Restore the doorbell status and also account for the doorbell
     * received when this vcpu was running */
     if (vcpu->arch.vcore->dpdes)
        vcpu->arch.doorbell_request |= kvmppc_get_dpdes(vcpu);


- Gautam

Re: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry

[kernel test robot]

Hi Vaibhav,

kernel test robot noticed the following build errors:

[auto build test ERROR on powerpc/topic/ppc-kvm]
[also build test ERROR on kvm/queue kvm/next mst-vhost/linux-next linus/master v7.2-rc7 next-20260813]
[cannot apply to kvm/linux-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Vaibhav-Jain/KVM-PPC-Book3S-HV-nestedv2-Don-t-drop-pending-doorbell-across-L2-entry/20260815-070415
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git topic/ppc-kvm
patch link:    https://lore.kernel.org/r/20260803034426.44249-1-vaibhav%40linux.ibm.com
patch subject: [PATCH] KVM: PPC: Book3S HV nestedv2: Don't drop pending doorbell across L2 entry
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20260815/202608150815.zhSReMmH-lkp@intel.com/config)
compiler: powerpc64-linux-gcc (GCC) 16.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260815/202608150815.zhSReMmH-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608150815.zhSReMmH-lkp@intel.com/

All errors (new ones prefixed by >>):

   arch/powerpc/kvm/book3s_hv.c: In function 'kvmhv_vcpu_entry_nestedv2':
>> arch/powerpc/kvm/book3s_hv.c:4304:25: error: 'cpu' undeclared (first use in this function)
    4304 |                         cpu->arch.doorbell_request = 0;
         |                         ^~~
   arch/powerpc/kvm/book3s_hv.c:4304:25: note: each undeclared identifier is reported only once for each function it appears in


vim +/cpu +4304 arch/powerpc/kvm/book3s_hv.c

  4248	
  4249	static int kvmhv_vcpu_entry_nestedv2(struct kvm_vcpu *vcpu, u64 time_limit,
  4250					     unsigned long lpcr, u64 *tb)
  4251	{
  4252		struct kvmhv_nestedv2_io *io;
  4253		unsigned long msr, i;
  4254		int trap;
  4255		long rc;
  4256	
  4257		io = &vcpu->arch.nestedv2_io;
  4258	
  4259		msr = mfmsr();
  4260		kvmppc_msr_hard_disable_set_facilities(vcpu, msr);
  4261		if (lazy_irq_pending())
  4262			return 0;
  4263	
  4264		if (vcpu->arch.doorbell_request)
  4265			kvmppc_set_dpdes(vcpu, 1);
  4266	
  4267		rc = kvmhv_nestedv2_flush_vcpu(vcpu, time_limit);
  4268		if (rc < 0)
  4269			return -EINVAL;
  4270	
  4271		kvmppc_gse_put_u64(io->vcpu_run_input, KVMPPC_GSID_LPCR, lpcr);
  4272	
  4273		accumulate_time(vcpu, &vcpu->arch.in_guest);
  4274		rc = plpar_guest_run_vcpu(0, vcpu->kvm->arch.lpid, vcpu->vcpu_id,
  4275					  &trap, &i);
  4276	
  4277		if (rc != H_SUCCESS) {
  4278			pr_err("KVM Guest Run VCPU hcall failed\n");
  4279			if (rc == H_INVALID_ELEMENT_ID)
  4280				pr_err("KVM: Guest Run VCPU invalid element id at %ld\n", i);
  4281			else if (rc == H_INVALID_ELEMENT_SIZE)
  4282				pr_err("KVM: Guest Run VCPU invalid element size at %ld\n", i);
  4283			else if (rc == H_INVALID_ELEMENT_VALUE)
  4284				pr_err("KVM: Guest Run VCPU invalid element value at %ld\n", i);
  4285			return -EINVAL;
  4286		}
  4287		accumulate_time(vcpu, &vcpu->arch.guest_exit);
  4288	
  4289		*tb = mftb();
  4290		kvmppc_gsm_reset(io->vcpu_message);
  4291		kvmppc_gsm_reset(io->vcore_message);
  4292		kvmppc_gsbm_zero(&io->valids);
  4293	
  4294		rc = kvmhv_nestedv2_parse_output(vcpu);
  4295		if (rc < 0)
  4296			return -EINVAL;
  4297	
  4298		/* Check if privileged door bell was requested and handled */
  4299		if (vcpu->arch.vcore->dpdes) {
  4300			kvmhv_nestedv2_cached_reload(vcpu, KVMPPC_GSID_DPDES);
  4301			if (vcpu->arch.vcore->dpdes)
  4302				vcpu->arch.doorbell_request |= vcpu->arch.vcore->dpdes;
  4303			else
> 4304				cpu->arch.doorbell_request = 0;
  4305		} else {
  4306			vcpu->arch.doorbell_request = 0;
  4307		}
  4308	
  4309		timer_rearm_host_dec(*tb);
  4310	
  4311		/* Record context switch and guest_run_time data */
  4312		if (kvmhv_get_l2_counters_status())
  4313			do_trace_nested_cs_time(vcpu);
  4314	
  4315		return trap;
  4316	}
  4317	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki