Re: [PATCH v7 09/11] KVM: arm64: guest debug, HW assisted debug support

From: Will Deacon
Date: Fri Jul 03 2015 - 05:23:57 EST


Hi Alex,

On Thu, Jul 02, 2015 at 02:50:33PM +0100, Alex Bennée wrote:
> Are you happy with this?:

[...]

> +/**
> + * kvm_arch_dev_ioctl_check_extension
> + *
> + * We currently assume that the number of HW registers is uniform
> + * across all CPUs (see cpuinfo_sanity_check).
> + */
> int kvm_arch_dev_ioctl_check_extension(long ext)
> {
> int r;
> @@ -64,6 +71,12 @@ int kvm_arch_dev_ioctl_check_extension(long ext)
> case KVM_CAP_ARM_EL1_32BIT:
> r = cpu_has_32bit_el1();
> break;
> + case KVM_CAP_GUEST_DEBUG_HW_BPS:
> + r = hw_breakpoint_slots(TYPE_INST);
> + break;
> + case KVM_CAP_GUEST_DEBUG_HW_WPS:
> + r = hw_breakpoint_slots(TYPE_DATA);
> + break;

Whilst I much prefer this code, it actually adds an unwanted dependency
on PERF_EVENTS that I didn't think about to start with. Sorry to keep
messing you about -- I guess your original patch is the best thing after
all.

Will
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/