From: Wudi Wang <[email protected]>
The version of GIC used by KVM is provided by gic_v3_kvm_info.
The KVM that supports GICv4 or GICv4.1 only checks GIC
version. Actually, the GIC and ITS need to work together.
So we add the checking of ITS version for KVM: If and only if
both GIC & ITS support GICv4, gic_kvm_info.has_v4 is true.
If and only if both GIC & ITS support GICv4.1,
gic_kvm_info.has_v4_1 is true.
Cc: Thomas Gleixner <[email protected]>
Cc: Marc Zyngier <[email protected]>
Signed-off-by: Wudi Wang <[email protected]>
Signed-off-by: Shaokun Zhang <[email protected]>
---
drivers/irqchip/irq-gic-common.h | 2 ++
drivers/irqchip/irq-gic-v3-its.c | 3 +++
drivers/irqchip/irq-gic-v3.c | 10 +++++-----
3 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
index ccba8b0fe0f5..e5d44998445a 100644
--- a/drivers/irqchip/irq-gic-common.h
+++ b/drivers/irqchip/irq-gic-common.h
@@ -10,6 +10,8 @@
#include <linux/irqdomain.h>
#include <linux/irqchip/arm-gic-common.h>
+extern struct gic_kvm_info gic_v3_kvm_info;
+
struct gic_quirk {
const char *desc;
const char *compatible;
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 2e6923c2c8a8..45d6163c14d5 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -5419,6 +5419,9 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
has_v4_1 |= is_v4_1(its);
}
+ gic_v3_kvm_info.has_v4 = has_v4;
+ gic_v3_kvm_info.has_v4_1 = has_v4_1;
+
/* Don't bother with inconsistent systems */
if (WARN_ON(!has_v4_1 && rdists->has_rvpeid))
rdists->has_rvpeid = false;
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 37a23aa6de37..7454f99bf580 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -103,7 +103,7 @@ EXPORT_SYMBOL(gic_nonsecure_priorities);
/* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */
static refcount_t *ppi_nmi_refs;
-static struct gic_kvm_info gic_v3_kvm_info;
+struct gic_kvm_info gic_v3_kvm_info;
static DEFINE_PER_CPU(bool, has_rss);
#define MPIDR_RS(mpidr) (((mpidr) & 0xF0UL) >> 4)
@@ -1850,8 +1850,8 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
if (!ret)
gic_v3_kvm_info.vcpu = r;
- gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
- gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
+ gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
+ gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
gic_set_kvm_info(&gic_v3_kvm_info);
}
@@ -2166,8 +2166,8 @@ static void __init gic_acpi_setup_kvm_info(void)
vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
}
- gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
- gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
+ gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
+ gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
gic_set_kvm_info(&gic_v3_kvm_info);
}
--
2.7.4
On Fri, 11 Jun 2021 06:52:26 +0100,
Shaokun Zhang <[email protected]> wrote:
>
> From: Wudi Wang <[email protected]>
>
> The version of GIC used by KVM is provided by gic_v3_kvm_info.
> The KVM that supports GICv4 or GICv4.1 only checks GIC
> version. Actually, the GIC and ITS need to work together.
> So we add the checking of ITS version for KVM: If and only if
> both GIC & ITS support GICv4, gic_kvm_info.has_v4 is true.
> If and only if both GIC & ITS support GICv4.1,
> gic_kvm_info.has_v4_1 is true.
>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Marc Zyngier <[email protected]>
> Signed-off-by: Wudi Wang <[email protected]>
> Signed-off-by: Shaokun Zhang <[email protected]>
> ---
> drivers/irqchip/irq-gic-common.h | 2 ++
> drivers/irqchip/irq-gic-v3-its.c | 3 +++
> drivers/irqchip/irq-gic-v3.c | 10 +++++-----
> 3 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
> index ccba8b0fe0f5..e5d44998445a 100644
> --- a/drivers/irqchip/irq-gic-common.h
> +++ b/drivers/irqchip/irq-gic-common.h
> @@ -10,6 +10,8 @@
> #include <linux/irqdomain.h>
> #include <linux/irqchip/arm-gic-common.h>
>
> +extern struct gic_kvm_info gic_v3_kvm_info;
> +
> struct gic_quirk {
> const char *desc;
> const char *compatible;
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 2e6923c2c8a8..45d6163c14d5 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -5419,6 +5419,9 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
> has_v4_1 |= is_v4_1(its);
> }
>
> + gic_v3_kvm_info.has_v4 = has_v4;
> + gic_v3_kvm_info.has_v4_1 = has_v4_1;
If you are going down that road: what if you have multiple ITSs,
implementing a variety of v3, v4, v4.1? We currently support this to
some extent, but this is breaking it.
What case are you exactly trying to fix?
> +
> /* Don't bother with inconsistent systems */
> if (WARN_ON(!has_v4_1 && rdists->has_rvpeid))
> rdists->has_rvpeid = false;
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index 37a23aa6de37..7454f99bf580 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -103,7 +103,7 @@ EXPORT_SYMBOL(gic_nonsecure_priorities);
> /* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */
> static refcount_t *ppi_nmi_refs;
>
> -static struct gic_kvm_info gic_v3_kvm_info;
> +struct gic_kvm_info gic_v3_kvm_info;
This will conflict with the rework that is in -next, and maybe cause
some lifetime issue (see how the structure is now tagged __initdata).
> static DEFINE_PER_CPU(bool, has_rss);
>
> #define MPIDR_RS(mpidr) (((mpidr) & 0xF0UL) >> 4)
> @@ -1850,8 +1850,8 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
> if (!ret)
> gic_v3_kvm_info.vcpu = r;
>
> - gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
> - gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
> + gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
> + gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
> gic_set_kvm_info(&gic_v3_kvm_info);
> }
>
> @@ -2166,8 +2166,8 @@ static void __init gic_acpi_setup_kvm_info(void)
> vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
> }
>
> - gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
> - gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
> + gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
> + gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
> gic_set_kvm_info(&gic_v3_kvm_info);
> }
Thanks,
M.
--
Without deviation from the norm, progress is not possible.
Hi Marc,
Apologies for reply so slow because of a short holiday in China.
On 2021/6/11 16:01, Marc Zyngier wrote:
> On Fri, 11 Jun 2021 06:52:26 +0100,
> Shaokun Zhang <[email protected]> wrote:
>>
>> From: Wudi Wang <[email protected]>
>>
>> The version of GIC used by KVM is provided by gic_v3_kvm_info.
>> The KVM that supports GICv4 or GICv4.1 only checks GIC
>> version. Actually, the GIC and ITS need to work together.
>> So we add the checking of ITS version for KVM: If and only if
>> both GIC & ITS support GICv4, gic_kvm_info.has_v4 is true.
>> If and only if both GIC & ITS support GICv4.1,
>> gic_kvm_info.has_v4_1 is true.
>>
>> Cc: Thomas Gleixner <[email protected]>
>> Cc: Marc Zyngier <[email protected]>
>> Signed-off-by: Wudi Wang <[email protected]>
>> Signed-off-by: Shaokun Zhang <[email protected]>
>> ---
>> drivers/irqchip/irq-gic-common.h | 2 ++
>> drivers/irqchip/irq-gic-v3-its.c | 3 +++
>> drivers/irqchip/irq-gic-v3.c | 10 +++++-----
>> 3 files changed, 10 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
>> index ccba8b0fe0f5..e5d44998445a 100644
>> --- a/drivers/irqchip/irq-gic-common.h
>> +++ b/drivers/irqchip/irq-gic-common.h
>> @@ -10,6 +10,8 @@
>> #include <linux/irqdomain.h>
>> #include <linux/irqchip/arm-gic-common.h>
>>
>> +extern struct gic_kvm_info gic_v3_kvm_info;
>> +
>> struct gic_quirk {
>> const char *desc;
>> const char *compatible;
>> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
>> index 2e6923c2c8a8..45d6163c14d5 100644
>> --- a/drivers/irqchip/irq-gic-v3-its.c
>> +++ b/drivers/irqchip/irq-gic-v3-its.c
>> @@ -5419,6 +5419,9 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
>> has_v4_1 |= is_v4_1(its);
>> }
>>
>> + gic_v3_kvm_info.has_v4 = has_v4;
>> + gic_v3_kvm_info.has_v4_1 = has_v4_1;
>
> If you are going down that road: what if you have multiple ITSs,
> implementing a variety of v3, v4, v4.1? We currently support this to
> some extent, but this is breaking it.
If we have multiple ITSs and GIC supports v4, there are two cases:
1. None of the ITS supports GICv4(GICv4.1), gic_v3_kvm_info.has_v4(has_v4_1) is false,
so the KVM will use GICv3;
2. At least one ITS supports GICv4(GICv4.1), gic_v3_kvm_info.has_v4(has_v4_1) is true,
so the KVM will use GICv4(GICv4.1);
Variable has_v4(has_v4_1) can do this.
>
> What case are you exactly trying to fix?
>
The first case that the KVM can use GICv4, it seem non-sensible. If we do check the
ITS version, it will give correct version for KVM.
>> +
>> /* Don't bother with inconsistent systems */
>> if (WARN_ON(!has_v4_1 && rdists->has_rvpeid))
>> rdists->has_rvpeid = false;
>> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
>> index 37a23aa6de37..7454f99bf580 100644
>> --- a/drivers/irqchip/irq-gic-v3.c
>> +++ b/drivers/irqchip/irq-gic-v3.c
>> @@ -103,7 +103,7 @@ EXPORT_SYMBOL(gic_nonsecure_priorities);
>> /* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */
>> static refcount_t *ppi_nmi_refs;
>>
>> -static struct gic_kvm_info gic_v3_kvm_info;
>> +struct gic_kvm_info gic_v3_kvm_info;
>
> This will conflict with the rework that is in -next, and maybe cause
> some lifetime issue (see how the structure is now tagged __initdata).
>
OOPS, I didn't check the -next branch, if you are happy about this patch and
I will rebase the newest -next and repost.
Thanks,
Shaokun
>> static DEFINE_PER_CPU(bool, has_rss);
>>
>> #define MPIDR_RS(mpidr) (((mpidr) & 0xF0UL) >> 4)
>> @@ -1850,8 +1850,8 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
>> if (!ret)
>> gic_v3_kvm_info.vcpu = r;
>>
>> - gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
>> - gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
>> + gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
>> + gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
>> gic_set_kvm_info(&gic_v3_kvm_info);
>> }
>>
>> @@ -2166,8 +2166,8 @@ static void __init gic_acpi_setup_kvm_info(void)
>> vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
>> }
>>
>> - gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
>> - gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
>> + gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
>> + gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
>> gic_set_kvm_info(&gic_v3_kvm_info);
>> }
>
> Thanks,
>
> M.
>