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Wed, 14 Oct 2026 20:44:18 +0000 Message-ID: <4bc68d06-a45f-45cc-80a4-f72806d5c976@intel.com> Date: Wed, 14 Oct 2026 13:44:15 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] x86/resctrl: Require force for L3 CAT on early Skylake-X To: Alexander Graf , Tony Luck CC: Dave Martin , James Morse , "Babu Moger" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H . 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Any insight into where the hang occurs? What is state of resctrl fs when kexec runs? Is it mounted (with which options)? Does the boot hang whether resctrl fs is mounted or not? If resctrl is mounted at time of kexec, has it been set up with different groups? Does kexec task run from a particular group? Does it make a difference if resctrl fs is unmounted before kexec? As I understand kexec takes system from resctrl without giving opportunity to reset. There should be no accumulation of state but system may boot up with settings left over from previous run. Unmounting resctrl would give opportunity to reset state so that new kernel can start with clean slate. What does "during secondary socket bringup" mean exactly? For example, is the hang when first CPU of second socket is onlined and found to be hanging in the resctrl online handler? Thank you. Reinette