On 2024-02-19 14:46, Zenghui Yu wrote:
On 2024/2/19 19:32, Marc Zyngier wrote:
For what it is worth, I've just tested both defconfig and my own configuration with both 4k (kvmtool, QEMU+KVM and on SynQuacer) and 16k (kvmtool), without any obvious problem.
I had a quick test on top of next-20240219 with defconfig. I can reproduce it with QEMU parameter '-cpu max -accel tcg', but things are fine with '-cpu max,lpa2=off -accel tcg'.
Bisection shows that the problem happens when we start putting the latest arm64 and kvmarm changes together. The following hack fixes the problem for me (but I **only** write it for kernel built with defconfig with ARM64_4K_PAGES=y atm).
I can investigate it further tomorrow (as it's too late now ;-) ). Or maybe Marc or Catalin can help fix it with a proper approach.
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 4f7662008ede..babdc3f4721b 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -2798,6 +2798,7 @@ static const struct arm64_cpu_capabilities arm64_features[] = { | .sign = FTR_SIGNED, | .field_pos = ID_AA64MMFR0_EL1_TGRAN4_SHIFT, | .min_field_value = ID_AA64MMFR0_EL1_TGRAN4_52_BIT, |+ .max_field_value = BIT(ID_AA64MMFR0_EL1_TGRAN4_WIDTH - 1) - 1, | #else | .sign = FTR_UNSIGNED, | .field_pos = ID_AA64MMFR0_EL1_TGRAN16_SHIFT,
Yup, got to that point too.
Working on a slightly more elaborate fix.
Thanks,
M.