From: Marc Zyngier Date: Mon, 28 Aug 2023 14:46:49 +0000 (+0100) Subject: KVM: arm64: Properly return allocated EL2 VA from hyp_alloc_private_va_range() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=3579dc742f76207a4854a87a8e3ce44434d7e308;p=linux.git KVM: arm64: Properly return allocated EL2 VA from hyp_alloc_private_va_range() Marek reports that his RPi4 spits out a warning at boot time, right at the point where the GICv2 virtual CPU interface gets mapped. Upon investigation, it seems that we never return the allocated VA and use whatever was on the stack at this point. Yes, this is good stuff, and Marek was pretty lucky that he ended-up with a VA that intersected with something that was already mapped. On my setup, this random value is plausible enough for the mapping to take place. Who knows what happens... Fixes: f156a7d13fc3 ("KVM: arm64: Remove size-order align in the nVHE hyp private VA range") Reported-by: Marek Szyprowski Tested-by: Marek Szyprowski Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Vincent Donnefort Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/79b0ad6e-0c2a-f777-d504-e40e8123d81d@samsung.com Link: https://lore.kernel.org/r/20230828153121.4179627-1-maz@kernel.org --- diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 587a104f66c37..482280fe22d7c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -652,6 +652,9 @@ int hyp_alloc_private_va_range(size_t size, unsigned long *haddr) mutex_unlock(&kvm_hyp_pgd_mutex); + if (!ret) + *haddr = base; + return ret; }