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List is: > cmt, mbmtotal, mbmlocal, l3cat, l3cdp, l2cat, l2cdp, > - mba, smba, bmec, abmc, sdciae, energy[:guid], > + mba, smba, bmec, abmc, sdciae, plza, energy[:guid], > perf[:guid]. > E.g. to turn on cmt and turn off mba use: > rdt=cmt,!mba > diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesystems/resctrl.rst > index e4b66af55ffb..f3e941404967 100644 > --- a/Documentation/filesystems/resctrl.rst > +++ b/Documentation/filesystems/resctrl.rst > @@ -28,6 +28,7 @@ SMBA (Slow Memory Bandwidth Allocation) "" > BMEC (Bandwidth Monitoring Event Configuration) "" > ABMC (Assignable Bandwidth Monitoring Counters) "" > SDCIAE (Smart Data Cache Injection Allocation Enforcement) "" > +PLZA (Privilege Level Zero Association) "" > =============================================================== ================================ > > Historically, new features were made visible by default in /proc/cpuinfo. This > diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c > index f452e8ce4cef..27e09cded829 100644 > --- a/arch/x86/kernel/cpu/resctrl/core.c > +++ b/arch/x86/kernel/cpu/resctrl/core.c > @@ -803,6 +803,7 @@ enum { > RDT_FLAG_BMEC, > RDT_FLAG_ABMC, > RDT_FLAG_SDCIAE, > + RDT_FLAG_PLZA, > }; > > #define RDT_OPT(idx, n, f) \ > @@ -830,6 +831,7 @@ static struct rdt_options rdt_options[] __ro_after_init = { > RDT_OPT(RDT_FLAG_BMEC, "bmec", X86_FEATURE_BMEC), > RDT_OPT(RDT_FLAG_ABMC, "abmc", X86_FEATURE_ABMC), > RDT_OPT(RDT_FLAG_SDCIAE, "sdciae", X86_FEATURE_SDCIAE), > + RDT_OPT(RDT_FLAG_PLZA, "plza", X86_FEATURE_PLZA), > }; > #define NUM_RDT_OPTIONS ARRAY_SIZE(rdt_options) > Sashiko reported: https://sashiko.dev/#/patchset/cover.1783461016.git.babu.moger%40amd.com?part=2 =================================================================== Is X86_FEATURE_PLZA actually evaluated anywhere in the resctrl subsystem? The commit message indicates this allows administrators to control PLZA visibility, but it appears there are no checks for this flag (e.g., using rdt_cpu_has(X86_FEATURE_PLZA)) in this patch or within the subsystem initialization logic to act on the administrator's input. Does this implementation actually configure the hardware and expose the feature, or is there a missing patch in this series that evaluates this flag? ====================================================================== This flag is passed to rdt_set_options and can be enabled or disabled using the rdt= boot parameter. This comment can be ignored. Thanks Babu