diff options
| author | Gautam Menghani <gautam@linux.ibm.com> | 2024-11-08 15:18:37 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2024-11-10 22:33:52 +1100 |
| commit | 44e5d21e6d3fd2a1fed7f0327cf72e99397e2eaf (patch) | |
| tree | 2b2b0d374b22c52c6c97b783c06cab7973d47269 /arch/powerpc | |
| parent | fb90dca828b6070709093934c6dec56489a2d91d (diff) | |
powerpc/pseries: Fix KVM guest detection for disabling hardlockup detector
As per the kernel documentation[1], hardlockup detector should
be disabled in KVM guests as it may give false positives. On
PPC, hardlockup detector is enabled inside KVM guests because
disable_hardlockup_detector() is marked as early_initcall and it
relies on kvm_guest static key (is_kvm_guest()) which is initialized
later during boot by check_kvm_guest(), which is a core_initcall.
check_kvm_guest() is also called in pSeries_smp_probe(), which is called
before initcalls, but it is skipped if KVM guest does not have doorbell
support or if the guest is launched with SMT=1.
Call check_kvm_guest() in disable_hardlockup_detector() so that
is_kvm_guest() check goes through fine and hardlockup detector can be
disabled inside the KVM guest.
[1]: Documentation/admin-guide/sysctl/kernel.rst
Fixes: 633c8e9800f3 ("powerpc/pseries: Enable hardlockup watchdog for PowerVM partitions")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241108094839.33084-1-gautam@linux.ibm.com
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/setup_64.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 22f83fbbc762..1edc7cd68c10 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -920,6 +920,7 @@ static int __init disable_hardlockup_detector(void) hardlockup_detector_disable(); #else if (firmware_has_feature(FW_FEATURE_LPAR)) { + check_kvm_guest(); if (is_kvm_guest()) hardlockup_detector_disable(); } |