github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-12 16:18:45 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

KVM: arm64: Read PMUVer as unsigned

Browse Source 
ID_AA64DFR0_EL1.PMUVer is an unsigned field, so this skips
initialization of host_data_ptr(nr_event_counters) for PMUv3 for Armv8.8
onwards as they appear as negative values.

Fix it by reading it as unsigned. Now ID_AA64DFR0_EL1_PMUVer_IMP_DEF
needs to be special cased, so use pmuv3_implemented() which already does
it.

Fixes: 2417218f2f ("KVM: arm64: Get rid of __kvm_get_mdcr_el2() and related warts")
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Colton Lewis <coltonlewis@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
James Clark 2026-03-05 16:28:17 +00:00 committed by Will Deacon
parent 1f318b96cc
commit 2e30447b23
1 changed files with 4 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
arch/arm64/kvm/debug.c
View File

@ -10,6 +10,7 @@
#include <linux/kvm_host.h>
#include <linux/hw_breakpoint.h>
#include <asm/arm_pmuv3.h>
#include <asm/debug-monitors.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_arm.h>
@ -75,8 +76,10 @@ static void kvm_arm_setup_mdcr_el2(struct kvm_vcpu *vcpu)
void kvm_init_host_debug_data(void)
{
u64 dfr0 = read_sysreg(id_aa64dfr0_el1);
unsigned int pmuver = cpuid_feature_extract_unsigned_field(dfr0,
ID_AA64DFR0_EL1_PMUVer_SHIFT);
if (cpuid_feature_extract_signed_field(dfr0, ID_AA64DFR0_EL1_PMUVer_SHIFT) > 0)
if (pmuv3_implemented(pmuver))
*host_data_ptr(nr_event_counters) = FIELD_GET(ARMV8_PMU_PMCR_N,
read_sysreg(pmcr_el0));