| Message ID | 20220107163324.2491209-5-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/arm: Reduced-IPA space and highmem fixes | expand |
Hi Marc, On 1/7/22 5:33 PM, Marc Zyngier wrote: > The highmem attribute is nothing but another way to express the > PA range of a VM. To support HW that has a smaller PA range then > what QEMU assumes, pass this PA range to the virt_set_memmap() > function, allowing it to correctly exclude highmem devices > if they are outside of the PA range. > > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > hw/arm/virt.c | 53 ++++++++++++++++++++++++++++++++++++++++++++------- > 1 file changed, 46 insertions(+), 7 deletions(-) > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > index 57c55e8a37..db4b0636e1 100644 > --- a/hw/arm/virt.c > +++ b/hw/arm/virt.c > @@ -1660,7 +1660,7 @@ static uint64_t virt_cpu_mp_affinity(VirtMachineState *vms, int idx) > return arm_cpu_mp_affinity(idx, clustersz); > } > > -static void virt_set_memmap(VirtMachineState *vms) > +static void virt_set_memmap(VirtMachineState *vms, int pa_bits) > { > MachineState *ms = MACHINE(vms); > hwaddr base, device_memory_base, device_memory_size, memtop; > @@ -1678,6 +1678,13 @@ static void virt_set_memmap(VirtMachineState *vms) > exit(EXIT_FAILURE); > } > > + /* > + * !highmem is exactly the same as limiting the PA space to 32bit, > + * irrespective of the underlying capabilities of the HW. > + */ > + if (!vms->highmem) > + pa_bits = 32; you need {} according to the QEMU coding style. Welcome to a new shiny world :-) > + > /* > * We compute the base of the high IO region depending on the > * amount of initial and device memory. The device memory start/size > @@ -1691,8 +1698,9 @@ static void virt_set_memmap(VirtMachineState *vms) > > /* Base address of the high IO region */ > memtop = base = device_memory_base + ROUND_UP(device_memory_size, GiB); > - if (!vms->highmem && memtop > 4 * GiB) { > - error_report("highmem=off, but memory crosses the 4GiB limit\n"); > + if (memtop > BIT_ULL(pa_bits)) { > + error_report("Addressing limited to %d bits, but memory exceeds it by %llu bytes\n", > + pa_bits, memtop - BIT_ULL(pa_bits)); > exit(EXIT_FAILURE); > } > if (base < device_memory_base) { > @@ -1711,7 +1719,13 @@ static void virt_set_memmap(VirtMachineState *vms) > vms->memmap[i].size = size; > base += size; > } > - vms->highest_gpa = (vms->highmem ? base : memtop) - 1; > + > + /* > + * 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; > @@ -1902,12 +1916,38 @@ static void machvirt_init(MachineState *machine) > unsigned int smp_cpus = machine->smp.cpus; > unsigned int max_cpus = machine->smp.max_cpus; Move the cpu_type check before? if (!cpu_type_valid(machine->cpu_type)) { error_report("mach-virt: CPU type %s not supported", machine->cpu_type); exit(1); } > > + possible_cpus = mc->possible_cpu_arch_ids(machine); > + > /* > * In accelerated mode, the memory map is computed earlier in kvm_type() > * to create a VM with the right number of IPA bits. > */ > if (!vms->memmap) { > - virt_set_memmap(vms); > + Object *cpuobj; > + ARMCPU *armcpu; > + int pa_bits; > + > + /* > + * Instanciate a temporary CPU object to find out about what > + * we are about to deal with. Once this is done, get rid of > + * the object. > + */ > + cpuobj = object_new(possible_cpus->cpus[0].type); > + armcpu = ARM_CPU(cpuobj); > + > + if (object_property_get_bool(cpuobj, "aarch64", NULL)) { > + pa_bits = arm_pamax(armcpu); > + } else if (arm_feature(&armcpu->env, ARM_FEATURE_LPAE)) { > + /* v7 with LPAE */ > + pa_bits = 40; > + } else { > + /* Anything else */ > + pa_bits = 32; > + } > + > + object_unref(cpuobj); > + > + virt_set_memmap(vms, pa_bits); > } > > /* We can probe only here because during property set > @@ -1989,7 +2029,6 @@ static void machvirt_init(MachineState *machine) > > create_fdt(vms); > > - possible_cpus = mc->possible_cpu_arch_ids(machine); > assert(possible_cpus->len == max_cpus); > for (n = 0; n < possible_cpus->len; n++) { > Object *cpuobj; > @@ -2646,7 +2685,7 @@ static int virt_kvm_type(MachineState *ms, const char *type_str) > max_vm_pa_size = kvm_arm_get_max_vm_ipa_size(ms, &fixed_ipa); > > /* we freeze the memory map to compute the highest gpa */ > - virt_set_memmap(vms); > + virt_set_memmap(vms, max_vm_pa_size); > > requested_pa_size = 64 - clz64(vms->highest_gpa); > Thanks Eric
On Mon, 10 Jan 2022 15:38:56 +0000, Eric Auger <eric.auger@redhat.com> wrote: > > Hi Marc, > > On 1/7/22 5:33 PM, Marc Zyngier wrote: > > The highmem attribute is nothing but another way to express the > > PA range of a VM. To support HW that has a smaller PA range then > > what QEMU assumes, pass this PA range to the virt_set_memmap() > > function, allowing it to correctly exclude highmem devices > > if they are outside of the PA range. > > > > Signed-off-by: Marc Zyngier <maz@kernel.org> > > --- > > hw/arm/virt.c | 53 ++++++++++++++++++++++++++++++++++++++++++++------- > > 1 file changed, 46 insertions(+), 7 deletions(-) > > > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > > index 57c55e8a37..db4b0636e1 100644 > > --- a/hw/arm/virt.c > > +++ b/hw/arm/virt.c > > @@ -1660,7 +1660,7 @@ static uint64_t virt_cpu_mp_affinity(VirtMachineState *vms, int idx) > > return arm_cpu_mp_affinity(idx, clustersz); > > } > > > > -static void virt_set_memmap(VirtMachineState *vms) > > +static void virt_set_memmap(VirtMachineState *vms, int pa_bits) > > { > > MachineState *ms = MACHINE(vms); > > hwaddr base, device_memory_base, device_memory_size, memtop; > > @@ -1678,6 +1678,13 @@ static void virt_set_memmap(VirtMachineState *vms) > > exit(EXIT_FAILURE); > > } > > > > + /* > > + * !highmem is exactly the same as limiting the PA space to 32bit, > > + * irrespective of the underlying capabilities of the HW. > > + */ > > + if (!vms->highmem) > > + pa_bits = 32; > you need {} according to the QEMU coding style. Welcome to a new shiny > world :-) Yeah. Between the reduced indentation and the avalanche of braces, my brain fails to pattern-match blocks of code. Amusing how inflexible you become after a couple of decades... > > + > > /* > > * We compute the base of the high IO region depending on the > > * amount of initial and device memory. The device memory start/size > > @@ -1691,8 +1698,9 @@ static void virt_set_memmap(VirtMachineState *vms) > > > > /* Base address of the high IO region */ > > memtop = base = device_memory_base + ROUND_UP(device_memory_size, GiB); > > - if (!vms->highmem && memtop > 4 * GiB) { > > - error_report("highmem=off, but memory crosses the 4GiB limit\n"); > > + if (memtop > BIT_ULL(pa_bits)) { > > + error_report("Addressing limited to %d bits, but memory exceeds it by %llu bytes\n", > > + pa_bits, memtop - BIT_ULL(pa_bits)); > > exit(EXIT_FAILURE); > > } > > if (base < device_memory_base) { > > @@ -1711,7 +1719,13 @@ static void virt_set_memmap(VirtMachineState *vms) > > vms->memmap[i].size = size; > > base += size; > > } > > - vms->highest_gpa = (vms->highmem ? base : memtop) - 1; > > + > > + /* > > + * 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; > > @@ -1902,12 +1916,38 @@ static void machvirt_init(MachineState *machine) > > unsigned int smp_cpus = machine->smp.cpus; > > unsigned int max_cpus = machine->smp.max_cpus; > Move the cpu_type check before? > > if (!cpu_type_valid(machine->cpu_type)) { > error_report("mach-virt: CPU type %s not supported", > machine->cpu_type); > exit(1); > } > > Yes, very good point. I wonder why this was tucked away past computing the memory map and the GIC configuration... Anyway, I'll move it up. Thanks, M.
diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 57c55e8a37..db4b0636e1 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -1660,7 +1660,7 @@ static uint64_t virt_cpu_mp_affinity(VirtMachineState *vms, int idx) return arm_cpu_mp_affinity(idx, clustersz); } -static void virt_set_memmap(VirtMachineState *vms) +static void virt_set_memmap(VirtMachineState *vms, int pa_bits) { MachineState *ms = MACHINE(vms); hwaddr base, device_memory_base, device_memory_size, memtop; @@ -1678,6 +1678,13 @@ static void virt_set_memmap(VirtMachineState *vms) exit(EXIT_FAILURE); } + /* + * !highmem is exactly the same as limiting the PA space to 32bit, + * irrespective of the underlying capabilities of the HW. + */ + if (!vms->highmem) + pa_bits = 32; + /* * We compute the base of the high IO region depending on the * amount of initial and device memory. The device memory start/size @@ -1691,8 +1698,9 @@ static void virt_set_memmap(VirtMachineState *vms) /* Base address of the high IO region */ memtop = base = device_memory_base + ROUND_UP(device_memory_size, GiB); - if (!vms->highmem && memtop > 4 * GiB) { - error_report("highmem=off, but memory crosses the 4GiB limit\n"); + if (memtop > BIT_ULL(pa_bits)) { + error_report("Addressing limited to %d bits, but memory exceeds it by %llu bytes\n", + pa_bits, memtop - BIT_ULL(pa_bits)); exit(EXIT_FAILURE); } if (base < device_memory_base) { @@ -1711,7 +1719,13 @@ static void virt_set_memmap(VirtMachineState *vms) vms->memmap[i].size = size; base += size; } - vms->highest_gpa = (vms->highmem ? base : memtop) - 1; + + /* + * 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; @@ -1902,12 +1916,38 @@ static void machvirt_init(MachineState *machine) unsigned int smp_cpus = machine->smp.cpus; unsigned int max_cpus = machine->smp.max_cpus; + possible_cpus = mc->possible_cpu_arch_ids(machine); + /* * In accelerated mode, the memory map is computed earlier in kvm_type() * to create a VM with the right number of IPA bits. */ if (!vms->memmap) { - virt_set_memmap(vms); + Object *cpuobj; + ARMCPU *armcpu; + int pa_bits; + + /* + * Instanciate a temporary CPU object to find out about what + * we are about to deal with. Once this is done, get rid of + * the object. + */ + cpuobj = object_new(possible_cpus->cpus[0].type); + armcpu = ARM_CPU(cpuobj); + + if (object_property_get_bool(cpuobj, "aarch64", NULL)) { + pa_bits = arm_pamax(armcpu); + } else if (arm_feature(&armcpu->env, ARM_FEATURE_LPAE)) { + /* v7 with LPAE */ + pa_bits = 40; + } else { + /* Anything else */ + pa_bits = 32; + } + + object_unref(cpuobj); + + virt_set_memmap(vms, pa_bits); } /* We can probe only here because during property set @@ -1989,7 +2029,6 @@ static void machvirt_init(MachineState *machine) create_fdt(vms); - possible_cpus = mc->possible_cpu_arch_ids(machine); assert(possible_cpus->len == max_cpus); for (n = 0; n < possible_cpus->len; n++) { Object *cpuobj; @@ -2646,7 +2685,7 @@ static int virt_kvm_type(MachineState *ms, const char *type_str) max_vm_pa_size = kvm_arm_get_max_vm_ipa_size(ms, &fixed_ipa); /* we freeze the memory map to compute the highest gpa */ - virt_set_memmap(vms); + virt_set_memmap(vms, max_vm_pa_size); requested_pa_size = 64 - clz64(vms->highest_gpa);
The highmem attribute is nothing but another way to express the PA range of a VM. To support HW that has a smaller PA range then what QEMU assumes, pass this PA range to the virt_set_memmap() function, allowing it to correctly exclude highmem devices if they are outside of the PA range. Signed-off-by: Marc Zyngier <maz@kernel.org> --- hw/arm/virt.c | 53 ++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 46 insertions(+), 7 deletions(-)