Re: [PATCH] KVM: arm64: Fix hypervisor address symbolization

From: Fuad Tabba
Date: Mon Jul 18 2022 - 05:08:51 EST


Hi Kalesh,

On Sat, Jul 16, 2022 at 12:58 AM Kalesh Singh <kaleshsingh@xxxxxxxxxx> wrote:
>
> With CONFIG_RANDOMIZE_BASE=y vmlinux addresses will resolve correctly
> from kallsyms. Fix this by adding the KASLR offset before printing the
> symbols.
>
> Based on arm64 for-next/stacktrace.
>
> Fixes: 6ccf9cb557bd ("KVM: arm64: Symbolize the nVHE HYP addresses")
> Reported-by: Fuad Tabba <tabba@xxxxxxxxxx>
> Signed-off-by: Kalesh Singh <kaleshsingh@xxxxxxxxxx>
> ---

Even with this patch applied I still don't get symbolization unless I
disable randomization, either by setting CONFIG_RANDOMIZE_BASE=n or
pass nokaslr as a kernel parameter. I tried both and in either case it
works.

Thanks,
/fuad


> arch/arm64/kvm/handle_exit.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
> index f66c0142b335..e43926ef2bc2 100644
> --- a/arch/arm64/kvm/handle_exit.c
> +++ b/arch/arm64/kvm/handle_exit.c
> @@ -347,10 +347,10 @@ void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr,
> kvm_err("nVHE hyp BUG at: %s:%u!\n", file, line);
> else
> kvm_err("nVHE hyp BUG at: [<%016llx>] %pB!\n", panic_addr,
> - (void *)panic_addr);
> + (void *)(panic_addr + kaslr_offset()));
> } else {
> kvm_err("nVHE hyp panic at: [<%016llx>] %pB!\n", panic_addr,
> - (void *)panic_addr);
> + (void *)(panic_addr + kaslr_offset()));
> }
>
> /*
>
> base-commit: 82a592c13b0aeff94d84d54183dae0b26384c95f
> --
> 2.37.0.170.g444d1eabd0-goog
>