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2023-12-15x86/mce: Add per-bank CMCI storm mitigationTony Luck
This is the core functionality to track CMCI storms at the machine check bank granularity. Subsequent patches will add the vendor specific hooks to supply input to the storm detection and take actions on the start/end of a storm. machine_check_poll() is called both by the CMCI interrupt code, and for periodic polls from a timer. Add a hook in this routine to maintain a bitmap history for each bank showing whether the bank logged an corrected error or not each time it is polled. In normal operation the interval between polls of these banks determines how far to shift the history. The 64 bit width corresponds to about one second. When a storm is observed a CPU vendor specific action is taken to reduce or stop CMCI from the bank that is the source of the storm. The bank is added to the bitmap of banks for this CPU to poll. The polling rate is increased to once per second. During a storm each bit in the history indicates the status of the bank each time it is polled. Thus the history covers just over a minute. Declare a storm for that bank if the number of corrected interrupts seen in that history is above some threshold (defined as 5 in this series, could be tuned later if there is data to suggest a better value). A storm on a bank ends if enough consecutive polls of the bank show no corrected errors (defined as 30, may also change). That calls the CPU vendor specific function to revert to normal operational mode, and changes the polling rate back to the default. [ bp: Massage. ] Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231115195450.12963-3-tony.luck@intel.com
2023-12-15x86/mce: Remove old CMCI storm mitigation codeTony Luck
When a "storm" of corrected machine check interrupts (CMCI) is detected this code mitigates by disabling CMCI interrupt signalling from all of the banks owned by the CPU that saw the storm. There are problems with this approach: 1) It is very coarse grained. In all likelihood only one of the banks was generating the interrupts, but CMCI is disabled for all. This means Linux may delay seeing and processing errors logged from other banks. 2) Although CMCI stands for Corrected Machine Check Interrupt, it is also used to signal when an uncorrected error is logged. This is a problem because these errors should be handled in a timely manner. Delete all this code in preparation for a finer grained solution. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com> Tested-by: Yazen Ghannam <yazen.ghannam@amd.com> Link: https://lore.kernel.org/r/20231115195450.12963-2-tony.luck@intel.com
2023-12-13x86/sev: Do the C-bit verification only on the BSPBorislav Petkov (AMD)
There's no need to do it on every AP. The C-bit value read on the BSP and also verified there, is used everywhere from now on. No functional changes - just a bit faster booting APs. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20231130132601.10317-1-bp@alien8.de
2023-12-13x86/head_64: Use TESTB instead of TESTL in secondary_startup_64_no_verify()Uros Bizjak
There is no need to use TESTL when checking the least-significant bit with a TEST instruction. Use TESTB, which is three bytes shorter: f6 05 00 00 00 00 01 testb $0x1,0x0(%rip) vs: f7 05 00 00 00 00 01 testl $0x1,0x0(%rip) 00 00 00 for the same effect. No functional changes intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231109201032.4439-1-ubizjak@gmail.com
2023-12-12x86/mce: Differentiate real hardware #MCs from TDX erratum onesKai Huang
The first few generations of TDX hardware have an erratum. Triggering it in Linux requires some kind of kernel bug involving relatively exotic memory writes to TDX private memory and will manifest via spurious-looking machine checks when reading the affected memory. Make an effort to detect these TDX-induced machine checks and spit out a new blurb to dmesg so folks do not think their hardware is failing. == Background == Virtually all kernel memory accesses operations happen in full cachelines. In practice, writing a "byte" of memory usually reads a 64 byte cacheline of memory, modifies it, then writes the whole line back. Those operations do not trigger this problem. This problem is triggered by "partial" writes where a write transaction of less than cacheline lands at the memory controller. The CPU does these via non-temporal write instructions (like MOVNTI), or through UC/WC memory mappings. The issue can also be triggered away from the CPU by devices doing partial writes via DMA. == Problem == A partial write to a TDX private memory cacheline will silently "poison" the line. Subsequent reads will consume the poison and generate a machine check. According to the TDX hardware spec, neither of these things should have happened. To add insult to injury, the Linux machine code will present these as a literal "Hardware error" when they were, in fact, a software-triggered issue. == Solution == In the end, this issue is hard to trigger. Rather than do something rash (and incomplete) like unmap TDX private memory from the direct map, improve the machine check handler. Currently, the #MC handler doesn't distinguish whether the memory is TDX private memory or not but just dump, for instance, below message: [...] mce: [Hardware Error]: CPU 147: Machine Check Exception: f Bank 1: bd80000000100134 [...] mce: [Hardware Error]: RIP 10:<ffffffffadb69870> {__tlb_remove_page_size+0x10/0xa0} ... [...] mce: [Hardware Error]: Run the above through 'mcelog --ascii' [...] mce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel [...] Kernel panic - not syncing: Fatal local machine check Which says "Hardware Error" and "Data load in unrecoverable area of kernel". Ideally, it's better for the log to say "software bug around TDX private memory" instead of "Hardware Error". But in reality the real hardware memory error can happen, and sadly such software-triggered #MC cannot be distinguished from the real hardware error. Also, the error message is used by userspace tool 'mcelog' to parse, so changing the output may break userspace. So keep the "Hardware Error". The "Data load in unrecoverable area of kernel" is also helpful, so keep it too. Instead of modifying above error log, improve the error log by printing additional TDX related message to make the log like: ... [...] mce: [Hardware Error]: Machine check: Data load in unrecoverable area of kernel [...] mce: [Hardware Error]: Machine Check: TDX private memory error. Possible kernel bug. Adding this additional message requires determination of whether the memory page is TDX private memory. There is no existing infrastructure to do that. Add an interface to query the TDX module to fill this gap. == Impact == This issue requires some kind of kernel bug to trigger. TDX private memory should never be mapped UC/WC. A partial write originating from these mappings would require *two* bugs, first mapping the wrong page, then writing the wrong memory. It would also be detectable using traditional memory corruption techniques like DEBUG_PAGEALLOC. MOVNTI (and friends) could cause this issue with something like a simple buffer overrun or use-after-free on the direct map. It should also be detectable with normal debug techniques. The one place where this might get nasty would be if the CPU read data then wrote back the same data. That would trigger this problem but would not, for instance, set off mechanisms like slab redzoning because it doesn't actually corrupt data. With an IOMMU at least, the DMA exposure is similar to the UC/WC issue. TDX private memory would first need to be incorrectly mapped into the I/O space and then a later DMA to that mapping would actually cause the poisoning event. [ dhansen: changelog tweaks ] Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Yuan Yao <yuan.yao@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/all/20231208170740.53979-18-dave.hansen%40intel.com
2023-12-12x86/CPU/AMD: Add X86_FEATURE_ZEN1Borislav Petkov (AMD)
Add a synthetic feature flag specifically for first generation Zen machines. There's need to have a generic flag for all Zen generations so make X86_FEATURE_ZEN be that flag. Fixes: 30fa92832f40 ("x86/CPU/AMD: Add ZenX generations flags") Suggested-by: Brian Gerst <brgerst@gmail.com> Suggested-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/dc3835e3-0731-4230-bbb9-336bbe3d042b@amd.com
2023-12-12iommu: Add mm_get_enqcmd_pasid() helper functionTina Zhang
mm_get_enqcmd_pasid() should be used by architecture code and closely related to learn the PASID value that the x86 ENQCMD operation should use for the mm. For the moment SMMUv3 uses this without any connection to ENQCMD, it will be cleaned up similar to how the prior patch made VT-d use the PASID argument of set_dev_pasid(). The motivation is to replace mm->pasid with an iommu private data structure that is introduced in a later patch. Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Tina Zhang <tina.zhang@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20231027000525.1278806-4-tina.zhang@intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-12-12iommu: Change kconfig around IOMMU_SVAJason Gunthorpe
Linus suggested that the kconfig here is confusing: https://lore.kernel.org/all/CAHk-=wgUiAtiszwseM1p2fCJ+sC4XWQ+YN4TanFhUgvUqjr9Xw@mail.gmail.com/ Let's break it into three kconfigs controlling distinct things: - CONFIG_IOMMU_MM_DATA controls if the mm_struct has the additional fields for the IOMMU. Currently only PASID, but later patches store a struct iommu_mm_data * - CONFIG_ARCH_HAS_CPU_PASID controls if the arch needs the scheduling bit for keeping track of the ENQCMD instruction. x86 will select this if IOMMU_SVA is enabled - IOMMU_SVA controls if the IOMMU core compiles in the SVA support code for iommu driver use and the IOMMU exported API This way ARM will not enable CONFIG_ARCH_HAS_CPU_PASID Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20231027000525.1278806-2-tina.zhang@intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-12-10x86/paravirt: Remove no longer needed paravirt patching codeJuergen Gross
Now that paravirt is using the alternatives patching infrastructure, remove the paravirt patching code. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20231210062138.2417-6-jgross@suse.com
2023-12-10x86/paravirt: Switch mixed paravirt/alternative calls to alternativesJuergen Gross
Instead of stacking alternative and paravirt patching, use the new ALT_FLAG_CALL flag to switch those mixed calls to pure alternative handling. Eliminate the need to be careful regarding the sequence of alternative and paravirt patching. [ bp: Touch up commit message. ] Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20231210062138.2417-5-jgross@suse.com
2023-12-10x86/alternative: Add indirect call patchingJuergen Gross
In order to prepare replacing of paravirt patching with alternative patching, add the capability to replace an indirect call with a direct one. This is done via a new flag ALT_FLAG_CALL as the target of the CALL instruction needs to be evaluated using the value of the location addressed by the indirect call. For convenience, add a macro for a default CALL instruction. In case it is being used without the new flag being set, it will result in a BUG() when being executed. As in most cases, the feature used will be X86_FEATURE_ALWAYS so add another macro ALT_CALL_ALWAYS usable for the flags parameter of the ALTERNATIVE macros. For a complete replacement, handle the special cases of calling a nop function and an indirect call of NULL the same way as paravirt does. [ bp: Massage commit message, fixup the debug output and clarify flow more. ] Co-developed-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231210062138.2417-4-jgross@suse.com
2023-12-10x86/paravirt: Move some functions and defines to alternative.cJuergen Gross
As a preparation for replacing paravirt patching completely by alternative patching, move some backend functions and #defines to the alternatives code and header. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231129133332.31043-3-jgross@suse.com
2023-12-10Merge tag 'x86_urgent_for_v6.7_rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Add a forgotten CPU vendor check in the AMD microcode post-loading callback so that the callback runs only on AMD - Make sure SEV-ES protocol negotiation happens only once and on the BSP * tag 'x86_urgent_for_v6.7_rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU/AMD: Check vendor in the AMD microcode callback x86/sev: Fix kernel crash due to late update to read-only ghcb_version
2023-12-08x86/virt/tdx: Use all system memory when initializing TDX module as TDX memoryKai Huang
Start to transit out the "multi-steps" to initialize the TDX module. TDX provides increased levels of memory confidentiality and integrity. This requires special hardware support for features like memory encryption and storage of memory integrity checksums. Not all memory satisfies these requirements. As a result, TDX introduced the concept of a "Convertible Memory Region" (CMR). During boot, the firmware builds a list of all of the memory ranges which can provide the TDX security guarantees. The list of these ranges is available to the kernel by querying the TDX module. CMRs tell the kernel which memory is TDX compatible. The kernel needs to build a list of memory regions (out of CMRs) as "TDX-usable" memory and pass them to the TDX module. Once this is done, those "TDX-usable" memory regions are fixed during module's lifetime. To keep things simple, assume that all TDX-protected memory will come from the page allocator. Make sure all pages in the page allocator *are* TDX-usable memory. As TDX-usable memory is a fixed configuration, take a snapshot of the memory configuration from memblocks at the time of module initialization (memblocks are modified on memory hotplug). This snapshot is used to enable TDX support for *this* memory configuration only. Use a memory hotplug notifier to ensure that no other RAM can be added outside of this configuration. This approach requires all memblock memory regions at the time of module initialization to be TDX convertible memory to work, otherwise module initialization will fail in a later SEAMCALL when passing those regions to the module. This approach works when all boot-time "system RAM" is TDX convertible memory and no non-TDX-convertible memory is hot-added to the core-mm before module initialization. For instance, on the first generation of TDX machines, both CXL memory and NVDIMM are not TDX convertible memory. Using kmem driver to hot-add any CXL memory or NVDIMM to the core-mm before module initialization will result in failure to initialize the module. The SEAMCALL error code will be available in the dmesg to help user to understand the failure. Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: https://lore.kernel.org/all/20231208170740.53979-7-dave.hansen%40intel.com
2023-12-08x86/virt/tdx: Detect TDX during kernel bootKai Huang
Intel Trust Domain Extensions (TDX) protects guest VMs from malicious host and certain physical attacks. A CPU-attested software module called 'the TDX module' runs inside a new isolated memory range as a trusted hypervisor to manage and run protected VMs. Pre-TDX Intel hardware has support for a memory encryption architecture called MKTME. The memory encryption hardware underpinning MKTME is also used for Intel TDX. TDX ends up "stealing" some of the physical address space from the MKTME architecture for crypto-protection to VMs. The BIOS is responsible for partitioning the "KeyID" space between legacy MKTME and TDX. The KeyIDs reserved for TDX are called 'TDX private KeyIDs' or 'TDX KeyIDs' for short. During machine boot, TDX microcode verifies that the BIOS programmed TDX private KeyIDs consistently and correctly programmed across all CPU packages. The MSRs are locked in this state after verification. This is why MSR_IA32_MKTME_KEYID_PARTITIONING gets used for TDX enumeration: it indicates not just that the hardware supports TDX, but that all the boot-time security checks passed. The TDX module is expected to be loaded by the BIOS when it enables TDX, but the kernel needs to properly initialize it before it can be used to create and run any TDX guests. The TDX module will be initialized by the KVM subsystem when KVM wants to use TDX. Detect platform TDX support by detecting TDX private KeyIDs. The TDX module itself requires one TDX KeyID as the 'TDX global KeyID' to protect its metadata. Each TDX guest also needs a TDX KeyID for its own protection. Just use the first TDX KeyID as the global KeyID and leave the rest for TDX guests. If no TDX KeyID is left for TDX guests, disable TDX as initializing the TDX module alone is useless. [ dhansen: add X86_FEATURE, replace helper function ] Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Link: https://lore.kernel.org/all/20231208170740.53979-1-dave.hansen%40intel.com
2023-12-07x86/entry: Convert INT 0x80 emulation to IDTENTRYThomas Gleixner
There is no real reason to have a separate ASM entry point implementation for the legacy INT 0x80 syscall emulation on 64-bit. IDTENTRY provides all the functionality needed with the only difference that it does not: - save the syscall number (AX) into pt_regs::orig_ax - set pt_regs::ax to -ENOSYS Both can be done safely in the C code of an IDTENTRY before invoking any of the syscall related functions which depend on this convention. Aside of ASM code reduction this prepares for detecting and handling a local APIC injected vector 0x80. [ kirill.shutemov: More verbose comments ] Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@vger.kernel.org> # v6.0+
2023-12-06x86/topology: convert to use arch_cpu_is_hotpluggable()Russell King (Oracle)
Convert x86 to use the arch_cpu_is_hotpluggable() helper rather than arch_register_cpu(). Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/E1r5R3w-00Cszy-6k@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-06x86/topology: use weak version of arch_unregister_cpu()Russell King (Oracle)
Since the x86 version of arch_unregister_cpu() is the same as the weak version, drop the x86 specific version. Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/E1r5R3r-00Cszs-2R@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-06x86/topology: Switch over to GENERIC_CPU_DEVICESJames Morse
Now that GENERIC_CPU_DEVICES calls arch_register_cpu(), which can be overridden by the arch code, switch over to this to allow common code to choose when the register_cpu() call is made. x86's struct cpus come from struct x86_cpu, which has no other members or users. Remove this and use the version defined by common code. This is an intermediate step to the logic being moved to drivers/acpi, where GENERIC_CPU_DEVICES will do the work when booting with acpi=off. This patch also has the effect of moving the registration of CPUs from subsys to driver core initialisation, prior to any initcalls running. ---- Changes since RFC: * Fixed the second copy of arch_register_cpu() used for non-hotplug Changes since RFC v2: * Remove duplicate of the weak generic arch_register_cpu(), spotted by Jonathan Cameron. Add note about initialisation order change. Changes since RFC v3: * Adapt to removal of EXPORT_SYMBOL()s Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/E1r5R3l-00Cszm-UA@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-06x86/topology: remove arch_*register_cpu() exportsRussell King (Oracle)
arch_register_cpu() and arch_unregister_cpu() are not used by anything that can be a module - they are used by drivers/base/cpu.c and drivers/acpi/acpi_processor.c, neither of which can be a module. Remove the exports. Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/E1r5R2r-00Csyh-7B@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-06x86: intel_epb: Don't rely on link orderJames Morse
intel_epb_init() is called as a subsys_initcall() to register cpuhp callbacks. The callbacks make use of get_cpu_device() which will return NULL unless register_cpu() has been called. register_cpu() is called from topology_init(), which is also a subsys_initcall(). This is fragile. Moving the register_cpu() to a different subsys_initcall() leads to a NULL dereference during boot. Make intel_epb_init() a late_initcall(), user-space can't provide a policy before this point anyway. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk> Acked-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/E1r5R2m-00Csyb-2S@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-03x86/microcode/intel: Set new revision only after a successful updateBorislav Petkov (AMD)
This was meant to be done only when early microcode got updated successfully. Move it into the if-branch. Also, make sure the current revision is read unconditionally and only once. Fixes: 080990aa3344 ("x86/microcode: Rework early revisions reporting") Reported-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Ashok Raj <ashok.raj@intel.com> Link: https://lore.kernel.org/r/ZWjVt5dNRjbcvlzR@a4bf019067fa.jf.intel.com
2023-12-02x86/CPU/AMD: Check vendor in the AMD microcode callbackBorislav Petkov (AMD)
Commit in Fixes added an AMD-specific microcode callback. However, it didn't check the CPU vendor the kernel runs on explicitly. The only reason the Zenbleed check in it didn't run on other x86 vendors hardware was pure coincidental luck: if (!cpu_has_amd_erratum(c, amd_zenbleed)) return; gives true on other vendors because they don't have those families and models. However, with the removal of the cpu_has_amd_erratum() in 05f5f73936fa ("x86/CPU/AMD: Drop now unused CPU erratum checking function") that coincidental condition is gone, leading to the zenbleed check getting executed on other vendors too. Add the explicit vendor check for the whole callback as it should've been done in the first place. Fixes: 522b1d69219d ("x86/cpu/amd: Add a Zenbleed fix") Cc: <stable@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231201184226.16749-1-bp@alien8.de
2023-12-01x86/pci: Use PCI_HEADER_TYPE_* instead of literalsIlpo Järvinen
Replace 0x7f and 0x80 literals with PCI_HEADER_TYPE_* defines. Link: https://lore.kernel.org/r/20231124090919.23687-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-12-01x86/microcode/intel: Remove redundant microcode late updated messageAshok Raj
After successful update, the late loading routine prints an update summary similar to: microcode: load: updated on 128 primary CPUs with 128 siblings microcode: revision: 0x21000170 -> 0x21000190 Remove the redundant message in the Intel side of the driver. [ bp: Massage commit message. ] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/ZWjYhedNfhAUmt0k@a4bf019067fa.jf.intel.com
2023-11-30x86/sev: Fix kernel crash due to late update to read-only ghcb_versionAshwin Dayanand Kamat
A write-access violation page fault kernel crash was observed while running cpuhotplug LTP testcases on SEV-ES enabled systems. The crash was observed during hotplug, after the CPU was offlined and the process was migrated to different CPU. setup_ghcb() is called again which tries to update ghcb_version in sev_es_negotiate_protocol(). Ideally this is a read_only variable which is initialised during booting. Trying to write it results in a pagefault: BUG: unable to handle page fault for address: ffffffffba556e70 #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation [ ...] Call Trace: <TASK> ? __die_body.cold+0x1a/0x1f ? __die+0x2a/0x35 ? page_fault_oops+0x10c/0x270 ? setup_ghcb+0x71/0x100 ? __x86_return_thunk+0x5/0x6 ? search_exception_tables+0x60/0x70 ? __x86_return_thunk+0x5/0x6 ? fixup_exception+0x27/0x320 ? kernelmode_fixup_or_oops+0xa2/0x120 ? __bad_area_nosemaphore+0x16a/0x1b0 ? kernel_exc_vmm_communication+0x60/0xb0 ? bad_area_nosemaphore+0x16/0x20 ? do_kern_addr_fault+0x7a/0x90 ? exc_page_fault+0xbd/0x160 ? asm_exc_page_fault+0x27/0x30 ? setup_ghcb+0x71/0x100 ? setup_ghcb+0xe/0x100 cpu_init_exception_handling+0x1b9/0x1f0 The fix is to call sev_es_negotiate_protocol() only in the BSP boot phase, and it only needs to be done once in any case. [ mingo: Refined the changelog. ] Fixes: 95d33bfaa3e1 ("x86/sev: Register GHCB memory when SEV-SNP is active") Suggested-by: Tom Lendacky <thomas.lendacky@amd.com> Co-developed-by: Bo Gan <bo.gan@broadcom.com> Signed-off-by: Bo Gan <bo.gan@broadcom.com> Signed-off-by: Ashwin Dayanand Kamat <ashwin.kamat@broadcom.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/1701254429-18250-1-git-send-email-kashwindayan@vmware.com
2023-11-29x86/CPU/AMD: Drop now unused CPU erratum checking functionBorislav Petkov (AMD)
Bye bye. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-14-bp@alien8.de
2023-11-29x86/CPU/AMD: Get rid of amd_erratum_1485[]Borislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-13-bp@alien8.de
2023-11-29x86/CPU/AMD: Get rid of amd_erratum_400[]Borislav Petkov (AMD)
Setting X86_BUG_AMD_E400 in init_amd() is early enough. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-12-bp@alien8.de
2023-11-29x86/CPU/AMD: Get rid of amd_erratum_383[]Borislav Petkov (AMD)
Set it in init_amd_gh() unconditionally as that is the F10h init function. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-11-bp@alien8.de
2023-11-29x86/CPU/AMD: Get rid of amd_erratum_1054[]Borislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-10-bp@alien8.de
2023-11-29x86/CPU/AMD: Move the DIV0 bug detection to the Zen1 init functionBorislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-9-bp@alien8.de
2023-11-29x86/CPU/AMD: Move Zenbleed check to the Zen2 init functionBorislav Petkov (AMD)
Prefix it properly so that it is clear which generation it is dealing with. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: http://lore.kernel.org/r/20231120104152.13740-8-bp@alien8.de
2023-11-29x86/CPU/AMD: Rename init_amd_zn() to init_amd_zen_common()Borislav Petkov (AMD)
Call it from all Zen init functions. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-7-bp@alien8.de
2023-11-29x86/CPU/AMD: Call the spectral chicken in the Zen2 init functionBorislav Petkov (AMD)
No functional change. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-6-bp@alien8.de
2023-11-29x86/CPU/AMD: Move erratum 1076 fix into the Zen1 init functionBorislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-5-bp@alien8.de
2023-11-29x86/CPU/AMD: Move the Zen3 BTC_NO detection to the Zen3 init functionBorislav Petkov (AMD)
No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-4-bp@alien8.de
2023-11-29x86/CPU/AMD: Carve out the erratum 1386 fixBorislav Petkov (AMD)
Call it on the affected CPU generations. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: http://lore.kernel.org/r/20231120104152.13740-3-bp@alien8.de
2023-11-29x86/CPU/AMD: Add ZenX generations flagsBorislav Petkov (AMD)
Add X86_FEATURE flags for each Zen generation. They should be used from now on instead of checking f/m/s. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/r/20231120104152.13740-2-bp@alien8.de
2023-11-28x86/MCE/AMD: Add new MA_LLC, USR_DP, and USR_CP bank typesMuralidhara M K
Add HWID and McaType values for new SMCA bank types. Signed-off-by: Muralidhara M K <muralidhara.mk@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231102114225.2006878-3-muralimk@amd.com
2023-11-27x86/mce/amd, EDAC/mce_amd: Move long names to decoder moduleYazen Ghannam
The long names of the SMCA banks are only used by the MCE decoder module. Move them out of the arch code and into the decoder module. [ bp: Name the long names array "smca_long_names", drop local ptr in decode_smca_error(), constify arrays. ] Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231118193248.1296798-5-yazen.ghannam@amd.com
2023-11-26Merge tag 'x86-urgent-2023-11-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode fixes from Ingo Molnar: "Fix/enhance x86 microcode version reporting: fix the bootup log spam, and remove the driver version announcement to avoid version confusion when distros backport fixes" * tag 'x86-urgent-2023-11-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Rework early revisions reporting x86/microcode: Remove the driver announcement and version
2023-11-24x86/cpu/intel_epb: Don't rely on link orderJames Morse
intel_epb_init() is called as a subsys_initcall() to register cpuhp callbacks. The callbacks make use of get_cpu_device() which will return NULL unless register_cpu() has been called. register_cpu() is called from topology_init(), which is also a subsys_initcall(). This is fragile. Moving the register_cpu() to a different subsys_initcall() leads to a NULL dereference during boot. Make intel_epb_init() a late_initcall(), user-space can't provide a policy before this point anyway. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Gavin Shan <gshan@redhat.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-11-23arch: include linux/cpu.h for trap_init() prototypeArnd Bergmann
some architectures run into a -Wmissing-prototypes warning for trap_init() arch/microblaze/kernel/traps.c:21:6: warning: no previous prototype for 'trap_init' [-Wmissing-prototypes] Include the right header to avoid this consistently, removing the extra declarations on m68k and x86 that were added as local workarounds already. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-11-23x86/ioapic: Remove unfinished sentence from commentAdrian Huang
[ mingo: Refine changelog. ] Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org
2023-11-22x86/mce/inject: Clear test status valueYazen Ghannam
AMD systems generally allow MCA "simulation" where MCA registers can be written with valid data and the full MCA handling flow can be tested by software. However, the platform on Scalable MCA systems, can prevent software from writing data to the MCA registers. There is no architectural way to determine this configuration. Therefore, the MCE injection module will check for this behavior by writing and reading back a test status value. This is done during module init, and the check can run on any CPU with any valid MCA bank. If MCA_STATUS writes are ignored by the platform, then there are no side effects on the hardware state. If the writes are not ignored, then the test status value will remain in the hardware MCA_STATUS register. It is likely that the value will not be overwritten by hardware or software, since the tested CPU and bank are arbitrary. Therefore, the user may see a spurious, synthetic MCA error reported whenever MCA is polled for this CPU. Clear the test value immediately after writing it. It is very unlikely that a valid MCA error is logged by hardware during the test. Errors that cause an #MC won't be affected. Fixes: 891e465a1bd8 ("x86/mce: Check whether writes to MCA_STATUS are getting ignored") Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20231118193248.1296798-2-yazen.ghannam@amd.com
2023-11-22Merge tag 'hyperv-fixes-signed-20231121' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv fixes from Wei Liu: - One fix for the KVP daemon (Ani Sinha) - Fix for the detection of E820_TYPE_PRAM in a Gen2 VM (Saurabh Sengar) - Micro-optimization for hv_nmi_unknown() (Uros Bizjak) * tag 'hyperv-fixes-signed-20231121' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: x86/hyperv: Use atomic_try_cmpxchg() to micro-optimize hv_nmi_unknown() x86/hyperv: Fix the detection of E820_TYPE_PRAM in a Gen2 VM hv/hv_kvp_daemon: Some small fixes for handling NM keyfiles
2023-11-22x86/hyperv: Use atomic_try_cmpxchg() to micro-optimize hv_nmi_unknown()Uros Bizjak
Use atomic_try_cmpxchg() instead of atomic_cmpxchg(*ptr, old, new) == old in hv_nmi_unknown(). On x86 the CMPXCHG instruction returns success in the ZF flag, so this change saves a compare after CMPXCHG. The generated asm code improves from: 3e: 65 8b 15 00 00 00 00 mov %gs:0x0(%rip),%edx 45: b8 ff ff ff ff mov $0xffffffff,%eax 4a: f0 0f b1 15 00 00 00 lock cmpxchg %edx,0x0(%rip) 51: 00 52: 83 f8 ff cmp $0xffffffff,%eax 55: 0f 95 c0 setne %al to: 3e: 65 8b 15 00 00 00 00 mov %gs:0x0(%rip),%edx 45: b8 ff ff ff ff mov $0xffffffff,%eax 4a: f0 0f b1 15 00 00 00 lock cmpxchg %edx,0x0(%rip) 51: 00 52: 0f 95 c0 setne %al No functional change intended. Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Wei Liu <wei.liu@kernel.org> Cc: Dexuan Cui <decui@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Link: https://lore.kernel.org/r/20231114170038.381634-1-ubizjak@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20231114170038.381634-1-ubizjak@gmail.com>
2023-11-21x86/apic: Drop apic::delivery_modeAndrew Cooper
This field is set to APIC_DELIVERY_MODE_FIXED in all cases, and is read exactly once. Fold the constant in uv_program_mmr() and drop the field. Searching for the origin of the stale HyperV comment reveals commit a31e58e129f7 ("x86/apic: Switch all APICs to Fixed delivery mode") which notes: As a consequence of this change, the apic::irq_delivery_mode field is now pointless, but this needs to be cleaned up in a separate patch. 6 years is long enough for this technical debt to have survived. [ bp: Fold in https://lore.kernel.org/r/20231121123034.1442059-1-andrew.cooper3@citrix.com ] Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Steve Wahl <steve.wahl@hpe.com> Link: https://lore.kernel.org/r/20231102-x86-apic-v1-1-bf049a2a0ed6@citrix.com
2023-11-21x86/microcode: Rework early revisions reportingBorislav Petkov (AMD)
The AMD side of the loader issues the microcode revision for each logical thread on the system, which can become really noisy on huge machines. And doing that doesn't make a whole lot of sense - the microcode revision is already in /proc/cpuinfo. So in case one is interested in the theoretical support of mixed silicon steppings on AMD, one can check there. What is also missing on the AMD side - something which people have requested before - is showing the microcode revision the CPU had *before* the early update. So abstract that up in the main code and have the BSP on each vendor provide those revision numbers. Then, dump them only once on driver init. On Intel, do not dump the patch date - it is not needed. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/CAHk-=wg=%2B8rceshMkB4VnKxmRccVLtBLPBawnewZuuqyx5U=3A@mail.gmail.com