In order to only keep the highmem devices that actually fit in
the PA range, check their location against the range and update
highest_gpa if they fit. If they don't, mark them them as disabled.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 hw/arm/virt.c | 34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index db4b0636e1..70b4773b3e 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -1711,21 +1711,43 @@ static void virt_set_memmap(VirtMachineState *vms, int pa_bits)
         base = vms->memmap[VIRT_MEM].base + LEGACY_RAMLIMIT_BYTES;
     }
 
+    /* We know for sure that at least the memory fits in the PA space */
+    vms->highest_gpa = memtop - 1;
+
     for (i = VIRT_LOWMEMMAP_LAST; i < ARRAY_SIZE(extended_memmap); i++) {
         hwaddr size = extended_memmap[i].size;
+        bool fits;
 
         base = ROUND_UP(base, size);
         vms->memmap[i].base = base;
         vms->memmap[i].size = size;
+
+        /*
+         * Check each device to see if they fit in the PA space,
+         * moving highest_gpa as we go.
+         *
+         * For each device that doesn't fit, disable it.
+         */
+        fits = (base + size) <= BIT_ULL(pa_bits);
+        if (fits) {
+            vms->highest_gpa = MAX(vms->highest_gpa, base + size - 1);
+        }
+
+        switch (i) {
+        case VIRT_HIGH_GIC_REDIST2:
+            vms->highmem_redists &= fits;
+            break;
+        case VIRT_HIGH_PCIE_ECAM:
+            vms->highmem_ecam &= fits;
+            break;
+        case VIRT_HIGH_PCIE_MMIO:
+            vms->highmem_mmio &= fits;
+            break;
+        }
+
         base += size;
     }
 
-    /*
-     * If base fits within pa_bits, all good. If it doesn't, limit it
-     * to the end of RAM, which is guaranteed to fit within pa_bits.
-     */
-    vms->highest_gpa = (base <= BIT_ULL(pa_bits) ? base : memtop) - 1;
-
     if (device_memory_size > 0) {
         ms->device_memory = g_malloc0(sizeof(*ms->device_memory));
         ms->device_memory->base = device_memory_base;
-- 
2.30.2

Hi Marc,

On 1/7/22 5:33 PM, Marc Zyngier wrote:
> In order to only keep the highmem devices that actually fit in
> the PA range, check their location against the range and update
> highest_gpa if they fit. If they don't, mark them them as disabled.
s/them them/them
>
> Signed-off-by: Marc Zyngier <maz@kernel.org>
> ---
>  hw/arm/virt.c | 34 ++++++++++++++++++++++++++++------
>  1 file changed, 28 insertions(+), 6 deletions(-)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index db4b0636e1..70b4773b3e 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -1711,21 +1711,43 @@ static void virt_set_memmap(VirtMachineState *vms, int pa_bits)
>          base = vms->memmap[VIRT_MEM].base + LEGACY_RAMLIMIT_BYTES;
>      }
>  
> +    /* We know for sure that at least the memory fits in the PA space */
> +    vms->highest_gpa = memtop - 1;
> +
>      for (i = VIRT_LOWMEMMAP_LAST; i < ARRAY_SIZE(extended_memmap); i++) {
>          hwaddr size = extended_memmap[i].size;
> +        bool fits;
>  
>          base = ROUND_UP(base, size);
>          vms->memmap[i].base = base;
>          vms->memmap[i].size = size;
> +
> +        /*
> +         * Check each device to see if they fit in the PA space,
> +         * moving highest_gpa as we go.
> +         *
> +         * For each device that doesn't fit, disable it.
> +         */
> +        fits = (base + size) <= BIT_ULL(pa_bits);
> +        if (fits) {
> +            vms->highest_gpa = MAX(vms->highest_gpa, base + size - 1);
why do you need the MAX()?
> +        }
> +        switch (i) {
> +        case VIRT_HIGH_GIC_REDIST2:
> +            vms->highmem_redists &= fits;
> +            break;
> +        case VIRT_HIGH_PCIE_ECAM:
> +            vms->highmem_ecam &= fits;
> +            break;
> +        case VIRT_HIGH_PCIE_MMIO:
> +            vms->highmem_mmio &= fits;
> +            break;
> +        }
> +
>          base += size;
>      }
>  
> -    /*
> -     * If base fits within pa_bits, all good. If it doesn't, limit it
> -     * to the end of RAM, which is guaranteed to fit within pa_bits.
> -     */
> -    vms->highest_gpa = (base <= BIT_ULL(pa_bits) ? base : memtop) - 1;
> -
>      if (device_memory_size > 0) {
>          ms->device_memory = g_malloc0(sizeof(*ms->device_memory));
>          ms->device_memory->base = device_memory_base;
Eric

On Mon, 10 Jan 2022 17:12:50 +0000,
Eric Auger <eric.auger@redhat.com> wrote:
> 
> Hi Marc,
> 
> On 1/7/22 5:33 PM, Marc Zyngier wrote:
> > In order to only keep the highmem devices that actually fit in
> > the PA range, check their location against the range and update
> > highest_gpa if they fit. If they don't, mark them them as disabled.
> s/them them/them
> >
> > Signed-off-by: Marc Zyngier <maz@kernel.org>
> > ---
> >  hw/arm/virt.c | 34 ++++++++++++++++++++++++++++------
> >  1 file changed, 28 insertions(+), 6 deletions(-)
> >
> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> > index db4b0636e1..70b4773b3e 100644
> > --- a/hw/arm/virt.c
> > +++ b/hw/arm/virt.c
> > @@ -1711,21 +1711,43 @@ static void virt_set_memmap(VirtMachineState *vms, int pa_bits)
> >          base = vms->memmap[VIRT_MEM].base + LEGACY_RAMLIMIT_BYTES;
> >      }
> >  
> > +    /* We know for sure that at least the memory fits in the PA space */
> > +    vms->highest_gpa = memtop - 1;
> > +
> >      for (i = VIRT_LOWMEMMAP_LAST; i < ARRAY_SIZE(extended_memmap); i++) {
> >          hwaddr size = extended_memmap[i].size;
> > +        bool fits;
> >  
> >          base = ROUND_UP(base, size);
> >          vms->memmap[i].base = base;
> >          vms->memmap[i].size = size;
> > +
> > +        /*
> > +         * Check each device to see if they fit in the PA space,
> > +         * moving highest_gpa as we go.
> > +         *
> > +         * For each device that doesn't fit, disable it.
> > +         */
> > +        fits = (base + size) <= BIT_ULL(pa_bits);
> > +        if (fits) {
> > +            vms->highest_gpa = MAX(vms->highest_gpa, base + size - 1);
> why do you need the MAX()?

Well spotted, I don't. Since we build the memmap by moving base
upward, I can directly use 'base + size - 1' as the new highest_gpa
value.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.