Re: [PATCH] KVM: arm64: nvhe: Fix build failure with gcc

[Vincent Donnefort <vdonnefort@google.com>]

On Tue, Jun 10, 2025 at 04:31:39PM +0100, Marc Zyngier wrote:
> On Tue, 10 Jun 2025 16:11:32 +0100,
> "Aneesh Kumar K.V (Arm)" <aneesh.kumar@kernel.org> wrote:
> > 
> > Address a build failure encountered with aarch64-linux-gnu-gcc version
> > 13.3.0 (Ubuntu 13.3.0-6ubuntu2~24.04)
> > 
> > /usr/bin/aarch64-linux-gnu-ld: arch/arm64/kvm/hyp/nvhe/kvm_nvhe.o: in function `__clock_mult_uint128':
> > /linux/work/arch/arm64/kvm/hyp/nvhe/clock.c:27:(.hyp.text+0x120d8): undefined reference to `__kvm_nvhe___lshrti3'
> > /linux/work/arch/arm64/kvm/hyp/nvhe/clock.c:27:(.hyp.text+0x120d8): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `__kvm_nvhe___lshrti3'
> 
> $ ls -l arch/arm64/kvm/hyp/nvhe/clock.c
> ls: cannot access 'arch/arm64/kvm/hyp/nvhe/clock.c': No such file or directory

Hum, this file is for the pKVM tracing support and is not upstream yet:

https://lore.kernel.org/all/20250516134031.661124-18-vdonnefort@google.com/

> 
> > 
> > Similar to commit 9bfe7553fadb ("arm64: Implement __lshrti3 library function"),
> > this change use the added helper.
> > 
> > Cc: Marc Zyngier <maz@kernel.org>
> > Cc: Oliver Upton <oliver.upton@linux.dev>
> > Cc: Joey Gouly <joey.gouly@arm.com>
> > Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
> > Cc: Zenghui Yu <yuzenghui@huawei.com>
> > Cc: Catalin Marinas <catalin.marinas@arm.com>
> > Cc: Will Deacon <will@kernel.org>
> > 
> > Suggested-by: Mark Rutland <mark.rutland@arm.com>
> > Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
> 
> What was recently introduced that triggers this? I'd like to
> understand what mandates it, and avoid it of at all possible.
> 
> 	M.
> 
> -- 
> Jazz isn't dead. It just smells funny.
>