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However, MCE support being unavailable does > not necessarily indicate an initialization failure. > > For example, a TDX guest with TD_CTLS.REDUCE_VE set and > FEATURE_PARAVIRT_CTLS.MCA clear does not enumerate the MCE and MCA > CPUID capabilities. This is an expected configuration, but it causes > the kernel to print: > > mce: Unable to init MCE device (rc: -5) > > MCE can also be unavailable because it was explicitly disabled with > mce=off or nomce. When it was disabled due to an earlier initialization > problem, the relevant path already reports the reason. > > Report MCE unavailability at informational level and return -ENODEV > directly instead of routing it through the common error path. > > Signed-off-by: Dexuan Cui > --- > arch/x86/kernel/cpu/mce/core.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c > index f3a793e3a6c8..24ac10075263 100644 > --- a/arch/x86/kernel/cpu/mce/core.c > +++ b/arch/x86/kernel/cpu/mce/core.c > @@ -2825,8 +2825,8 @@ static __init int mcheck_init_device(void) > MAYBE_BUILD_BUG_ON(__VIRTUAL_MASK_SHIFT >= 63); > > if (!mce_available(&boot_cpu_data)) { > - err = -EIO; > - goto err_out; > + pr_info("MCE is unavailable\n"); > + return -ENODEV; > } > > if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) { > -- I like this idea. I've seen cases where 'mce=off' is used for test cases. It'd be nice to have an explicit message like this to distinguish from true init failures. Reviewed-by: Yazen Ghannam Thanks, Yazen