blaster4385/linux-IllusionX/arch/x86/kernel/cpu/mtrr, branch v6.13

x86/cpu: KVM: Add common defines for architectural memory types (PAT, MTRRs, etc.)

2024-08-22T18:25:46Z

Add defines for the architectural memory types that can be shoved into various MSRs and registers, e.g. MTRRs, PAT, VMX capabilities MSRs, EPTPs, etc. While most MSRs/registers support only a subset of all memory types, the values themselves are architectural and identical across all users. Leave the goofy MTRR_TYPE_* definitions as-is since they are in a uapi header, but add compile-time assertions to connect the dots (and sanity check that the msr-index.h values didn't get fat-fingered). Keep the VMX_EPTP_MT_* defines so that it's slightly more obvious that the EPTP holds a single memory type in 3 of its 64 bits; those bits just happen to be 2:0, i.e. don't need to be shifted. Opportunistically use X86_MEMTYPE_WB instead of an open coded '6' in setup_vmcs_config(). No functional change intended. Reviewed-by: Thomas Gleixner Acked-by: Kai Huang Reviewed-by: Xiaoyao Li Reviewed-by: Kai Huang Link: https://lore.kernel.org/r/20240605231918.2915961-2-seanjc@google.com Signed-off-by: Sean Christopherson

x86/mtrr: Check if fixed MTRRs exist before saving them

2024-08-08T15:03:12Z

MTRRs have an obsolete fixed variant for fine grained caching control of the 640K-1MB region that uses separate MSRs. This fixed variant has a separate capability bit in the MTRR capability MSR. So far all x86 CPUs which support MTRR have this separate bit set, so it went unnoticed that mtrr_save_state() does not check the capability bit before accessing the fixed MTRR MSRs. Though on a CPU that does not support the fixed MTRR capability this results in a #GP. The #GP itself is harmless because the RDMSR fault is handled gracefully, but results in a WARN_ON(). Add the missing capability check to prevent this. Fixes: 2b1f6278d77c ("[PATCH] x86: Save the MTRRs of the BSP before booting an AP") Signed-off-by: Andi Kleen Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240808000244.946864-1-ak@linux.intel.com

x86/CPU/AMD: Track SNP host status with cc_platform_*()

2024-04-04T08:40:30Z

The host SNP worthiness can determined later, after alternatives have been patched, in snp_rmptable_init() depending on cmdline options like iommu=pt which is incompatible with SNP, for example. Which means that one cannot use X86_FEATURE_SEV_SNP and will need to have a special flag for that control. Use that newly added CC_ATTR_HOST_SEV_SNP in the appropriate places. Move kdump_sev_callback() to its rightful place, while at it. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Tom Lendacky Tested-by: Srikanth Aithal Link: https://lore.kernel.org/r/20240327154317.29909-6-bp@alien8.de

x86/mtrr: Don't print errors if MtrrFixDramModEn is set when SNP enabled

2024-01-29T16:24:27Z

SNP enabled platforms require the MtrrFixDramModeEn bit to be set across all CPUs when SNP is enabled. Therefore, don't print error messages when MtrrFixDramModeEn is set when bringing CPUs online. Closes: https://lore.kernel.org/kvm/68b2d6bf-bce7-47f9-bebb-2652cc923ff9@linux.microsoft.com/ Reported-by: Jeremi Piotrowski Signed-off-by: Ashish Kalra Signed-off-by: Michael Roth Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/20240126041126.1927228-6-michael.roth@amd.com

x86/mtrr: Document missing function parameters in kernel-doc

2023-11-20T09:19:27Z

Add text explaining what they do. No functional changes. Closes: https://lore.kernel.org/oe-kbuild-all/202311130104.9xKAKzke-lkp@intel.com/ Reported-by: kernel test robot Signed-off-by: Borislav Petkov (AMD) Link: https://lore.kernel.org/r/202311130104.9xKAKzke-lkp@intel.com

x86/mtrr: Unify debugging printing

2023-06-01T13:04:33Z

Put all the debugging output behind "mtrr=debug" and get rid of "mtrr_cleanup_debug" which wasn't even documented anywhere. No functional changes. Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/20230531174857.GDZHeIib57h5lT5Vh1@fat_crate.local

x86/mtrr: Remove unused code

2023-06-01T13:04:33Z

mtrr_centaur_report_mcr() isn't used by anyone, so it can be removed. Signed-off-by: Juergen Gross Signed-off-by: Borislav Petkov (AMD) Tested-by: Michael Kelley Link: https://lore.kernel.org/r/20230502120931.20719-17-jgross@suse.com Signed-off-by: Borislav Petkov (AMD)

x86/mtrr: Don't let mtrr_type_lookup() return MTRR_TYPE_INVALID

2023-06-01T13:04:33Z

mtrr_type_lookup() should always return a valid memory type. In case there is no information available, it should return the default UC. This will remove the last case where mtrr_type_lookup() can return MTRR_TYPE_INVALID, so adjust the comment in include/uapi/asm/mtrr.h. Note that removing the MTRR_TYPE_INVALID #define from that header could break user code, so it has to stay. At the same time the mtrr_type_lookup() stub for the !CONFIG_MTRR case should set uniform to 1, as if the memory range would be covered by no MTRR at all. Suggested-by: Linus Torvalds Signed-off-by: Juergen Gross Signed-off-by: Borislav Petkov (AMD) Tested-by: Michael Kelley Link: https://lore.kernel.org/r/20230502120931.20719-15-jgross@suse.com Signed-off-by: Borislav Petkov (AMD)

x86/mtrr: Use new cache_map in mtrr_type_lookup()

2023-06-01T13:04:33Z

Instead of crawling through the MTRR register state, use the new cache_map for looking up the cache type(s) of a memory region. This allows now to set the uniform parameter according to the uniformity of the cache mode of the region, instead of setting it only if the complete region is mapped by a single MTRR. This now includes even the region covered by the fixed MTRR registers. Make sure uniform is always set. [ bp: Massage. ] [ jgross: Explain mtrr_type_lookup() logic. ] Signed-off-by: Juergen Gross Signed-off-by: Borislav Petkov (AMD) Tested-by: Michael Kelley Link: https://lore.kernel.org/r/20230502120931.20719-14-jgross@suse.com Signed-off-by: Borislav Petkov (AMD)

x86/mtrr: Add mtrr=debug command line option

2023-06-01T13:04:33Z

Add a new command line option "mtrr=debug" for getting debug output after building the new cache mode map. The output will include MTRR register values and the resulting map. Signed-off-by: Juergen Gross Signed-off-by: Borislav Petkov (AMD) Tested-by: Michael Kelley Link: https://lore.kernel.org/r/20230502120931.20719-13-jgross@suse.com Signed-off-by: Borislav Petkov (AMD)