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2023-05-29x86/smp: Initialize cpu_primary_thread_mask lateThomas Gleixner
Marking primary threads in the cpumask during early boot is only correct in certain configurations, but broken e.g. for the legacy hyperthreading detection. This is due to the complete mess in the CPUID evaluation code which initializes smp_num_siblings only half during early init and fixes it up later when identify_boot_cpu() is invoked. So using smp_num_siblings before identify_boot_cpu() leads to incorrect results. Fixing the early CPU init code to provide the proper data is a larger scale surgery as the code has dependencies on data structures which are not initialized during early boot. Move the initialization of cpu_primary_thread_mask wich depends on smp_num_siblings being correct to an early initcall so that it is set up correctly before SMP bringup. Fixes: f54d4434c281 ("x86/apic: Provide cpu_primary_thread mask") Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: https://lore.kernel.org/r/87sfbhlwp9.ffs@tglx
2023-05-15x86/smpboot: Support parallel startup of secondary CPUsDavid Woodhouse
In parallel startup mode the APs are kicked alive by the control CPU quickly after each other and run through the early startup code in parallel. The real-mode startup code is already serialized with a bit-spinlock to protect the real-mode stack. In parallel startup mode the smpboot_control variable obviously cannot contain the Linux CPU number so the APs have to determine their Linux CPU number on their own. This is required to find the CPUs per CPU offset in order to find the idle task stack and other per CPU data. To achieve this, export the cpuid_to_apicid[] array so that each AP can find its own CPU number by searching therein based on its APIC ID. Introduce a flag in the top bits of smpboot_control which indicates that the AP should find its CPU number by reading the APIC ID from the APIC. This is required because CPUID based APIC ID retrieval can only provide the initial APIC ID, which might have been overruled by the firmware. Some AMD APUs come up with APIC ID = initial APIC ID + 0x10, so the APIC ID to CPU number lookup would fail miserably if based on CPUID. Also virtualization can make its own APIC ID assignements. The only requirement is that the APIC IDs are consistent with the APCI/MADT table. For the boot CPU or in case parallel bringup is disabled the control bits are empty and the CPU number is directly available in bit 0-23 of smpboot_control. [ tglx: Initial proof of concept patch with bitlock and APIC ID lookup ] [ dwmw2: Rework and testing, commit message, CPUID 0x1 and CPU0 support ] [ seanc: Fix stray override of initial_gs in common_cpu_up() ] [ Oleksandr Natalenko: reported suspend/resume issue fixed in x86_acpi_suspend_lowlevel ] [ tglx: Make it read the APIC ID from the APIC instead of using CPUID, split the bitlock part out ] Co-developed-by: Thomas Gleixner <tglx@linutronix.de> Co-developed-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205257.411554373@linutronix.de
2023-05-15x86/apic: Save the APIC virtual base addressThomas Gleixner
For parallel CPU brinugp it's required to read the APIC ID in the low level startup code. The virtual APIC base address is a constant because its a fix-mapped address. Exposing that constant which is composed via macros to assembly code is non-trivial due to header inclusion hell. Aside of that it's constant only because of the vsyscall ABI requirement. Once vsyscall is out of the picture the fixmap can be placed at runtime. Avoid header hell, stay flexible and store the address in a variable which can be exposed to the low level startup code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205257.299231005@linutronix.de
2023-05-15x86/apic: Provide cpu_primary_thread maskThomas Gleixner
Make the primary thread tracking CPU mask based in preparation for simpler handling of parallel bootup. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205257.186599880@linutronix.de
2023-04-25Merge tag 'x86-apic-2023-04-24' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Thomas Gleixner: - Fix the incorrect handling of atomic offset updates in reserve_eilvt_offset() The check for the return value of atomic_cmpxchg() is not compared against the old value, it is compared against the new value, which makes it two round on success. Convert it to atomic_try_cmpxchg() which does the right thing. - Handle IO/APIC less systems correctly When IO/APIC is not advertised by ACPI then the computation of the lower bound for dynamically allocated interrupts like MSI goes wrong. This lower bound is used to exclude the IO/APIC legacy GSI space as that must stay reserved for the legacy interrupts. In case that the system, e.g. VM, does not advertise an IO/APIC the lower bound stays at 0. 0 is an invalid interrupt number except for the legacy timer interrupt on x86. The return value is unchecked in the core code, so it ends up to allocate interrupt number 0 which is subsequently considered to be invalid by the caller, e.g. the MSI allocation code. A similar problem was already cured for device tree based systems years ago, but that missed - or did not envision - the zero IO/APIC case. Consolidate the zero check and return the provided "from" argument to the core code call site, which is guaranteed to be greater than 0. - Simplify the X2APIC cluster CPU mask logic for CPU hotplug Per cluster CPU masks are required for X2APIC in cluster mode to determine the correct cluster for a target CPU when calculating the destination for IPIs These masks are established when CPUs are borught up. The first CPU in a cluster must allocate a new cluster CPU mask. As this happens during the early startup of a CPU, where memory allocations cannot be done, the mask has to be allocated by the control CPU. The current implementation allocates a clustermask just in case and if the to be brought up CPU is the first in a cluster the CPU takes over this allocation from a global pointer. This works nicely in the fully serialized CPU bringup scenario which is used today, but would fail completely for parallel bringup of CPUs. The cluster association of a CPU can be computed from the APIC ID which is enumerated by ACPI/MADT. So the cluster CPU masks can be preallocated and associated upfront and the upcoming CPUs just need to set their corresponding bit. Aside of preparing for parallel bringup this is a valuable simplification on its own. - Remove global variables which control the early startup of secondary CPUs on 64-bit The only information which is needed by a starting CPU is the Linux CPU number. The CPU number allows it to retrieve the rest of the required data from already existing per CPU storage. So instead of initial_stack, early_gdt_desciptor and initial_gs provide a new variable smpboot_control which contains the Linux CPU number for now. The starting CPU can retrieve and compute all required information for startup from there. Aside of being a cleanup, this is also preparing for parallel CPU bringup, where starting CPUs will look up their Linux CPU number via the APIC ID, when smpboot_control has the corresponding control bit set. - Make cc_vendor globally accesible Subsequent parallel bringup changes require access to cc_vendor because confidental computing platforms need special treatment in the early startup phase vs. CPUID and APCI ID readouts. The change makes cc_vendor global and provides stub accessors in case that CONFIG_ARCH_HAS_CC_PLATFORM is not set. This was merged from the x86/cc branch in anticipation of further parallel bringup commits which require access to cc_vendor. Due to late discoveries of fundamental issue with those patches these commits never happened. The merge commit is unfortunately in the middle of the APIC commits so unraveling it would have required a rebase or revert. As the parallel bringup seems to be well on its way for 6.5 this would be just pointless churn. As the commit does not contain any functional change it's not a risk to keep it. * tag 'x86-apic-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ioapic: Don't return 0 from arch_dynirq_lower_bound() x86/apic: Fix atomic update of offset in reserve_eilvt_offset() x86/coco: Export cc_vendor x86/smpboot: Reference count on smpboot_setup_warm_reset_vector() x86/smpboot: Remove initial_gs x86/smpboot: Remove early_gdt_descr on 64-bit x86/smpboot: Remove initial_stack on 64-bit x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallel
2023-04-12x86/ioapic: Don't return 0 from arch_dynirq_lower_bound()Saurabh Sengar
arch_dynirq_lower_bound() is invoked by the core interrupt code to retrieve the lowest possible Linux interrupt number for dynamically allocated interrupts like MSI. The x86 implementation uses this to exclude the IO/APIC GSI space. This works correctly as long as there is an IO/APIC registered, but returns 0 if not. This has been observed in VMs where the BIOS does not advertise an IO/APIC. 0 is an invalid interrupt number except for the legacy timer interrupt on x86. The return value is unchecked in the core code, so it ends up to allocate interrupt number 0 which is subsequently considered to be invalid by the caller, e.g. the MSI allocation code. The function has already a check for 0 in the case that an IO/APIC is registered, as ioapic_dynirq_base is 0 in case of device tree setups. Consolidate this and zero check for both ioapic_dynirq_base and gsi_top, which is used in the case that no IO/APIC is registered. Fixes: 3e5bedc2c258 ("x86/apic: Fix arch_dynirq_lower_bound() bug for DT enabled machines") Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/1679988604-20308-1-git-send-email-ssengar@linux.microsoft.com
2023-04-07x86/apic: Fix atomic update of offset in reserve_eilvt_offset()Uros Bizjak
The detection of atomic update failure in reserve_eilvt_offset() is not correct. The value returned by atomic_cmpxchg() should be compared to the old value from the location to be updated. If these two are the same, then atomic update succeeded and "eilvt_offsets[offset]" location is updated to "new" in an atomic way. Otherwise, the atomic update failed and it should be retried with the value from "eilvt_offsets[offset]" - exactly what atomic_try_cmpxchg() does in a correct and more optimal way. Fixes: a68c439b1966c ("apic, x86: Check if EILVT APIC registers are available (AMD only)") Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230227160917.107820-1-ubizjak@gmail.com
2023-03-26x86/ioremap: Add hypervisor callback for private MMIO mapping in coco VMMichael Kelley
Current code always maps MMIO devices as shared (decrypted) in a confidential computing VM. But Hyper-V guest VMs on AMD SEV-SNP with vTOM use a paravisor running in VMPL0 to emulate some devices, such as the IO-APIC and TPM. In such a case, the device must be accessed as private (encrypted) because the paravisor emulates the device at an address below vTOM, where all accesses are encrypted. Add a new hypervisor callback to determine if an MMIO address should be mapped private. The callback allows hypervisor-specific code to handle any quirks, the use of a paravisor, etc. in determining whether a mapping must be private. If the callback is not used by a hypervisor, default to returning "false", which is consistent with normal coco VM behavior. Use this callback as another special case to check for when doing ioremap(). Just checking the starting address is sufficient as an ioremap range must be all private or all shared. Also make the callback in early boot IO-APIC mapping code that uses the fixmap. [ bp: Touchups. ] Signed-off-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/1678329614-3482-2-git-send-email-mikelley@microsoft.com
2023-03-21x86/apic/x2apic: Allow CPU cluster_mask to be populated in parallelDavid Woodhouse
Each of the sibling CPUs in a cluster uses the same clustermask. The first CPU in a cluster will need a new clustermask allocated, while subsequent siblings will use the same clustermask as the first. However, the CPU being brought up cannot yet perform memory allocations at the point that this occurs in init_x2apic_ldr(). So at present, the alloc_clustermask() function allocates a clustermask just in case it's needed, storing it in the global cluster_hotplug_mask. A CPU which is the first sibling of a cluster will "take" it from there and set cluster_hotplug_mask to NULL, in order for alloc_clustermask() to allocate a new one before bringing up the next CPU. To facilitate parallel bringup of CPUs in future, switch to a model where alloc_clustermask() prepopulates the clustermask in the per_cpu data for each present CPU in the cluster in advance. All that the CPU needs to do for itself in init_x2apic_ldr() is set its own bit in that mask. The 'node' and 'clusterid' members of struct cluster_mask are thus redundant, and it can become a simple struct cpumask instead. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Usama Arif <usama.arif@bytedance.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Paul E. McKenney <paulmck@kernel.org> Tested-by: Kim Phillips <kim.phillips@amd.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20230316222109.1940300-2-usama.arif@bytedance.com
2023-02-13x86/ioapic: Use irq_domain_create_hierarchy()Johan Hovold
Use the irq_domain_create_hierarchy() helper to create the hierarchical domain, which both serves as documentation and avoids poking at irqdomain internals. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Hsin-Yi Wang <hsinyi@chromium.org> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230213104302.17307-13-johan+linaro@kernel.org
2022-12-12Merge tag 'x86-apic-2022-12-10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic update from Thomas Gleixner: "A set of changes for the x86 APIC code: - Handle the case where x2APIC is enabled and locked by the BIOS on a kernel with CONFIG_X86_X2APIC=n gracefully. Instead of a panic which does not make it to the graphical console during very early boot, simply disable the local APIC completely and boot with the PIC and very limited functionality, which allows to diagnose the issue - Convert x86 APIC device tree bindings to YAML - Extend x86 APIC device tree bindings to configure interrupt delivery mode and handle this in during init. This allows to boot with device tree on platforms which lack a legacy PIC" * tag 'x86-apic-2022-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/of: Add support for boot time interrupt delivery mode configuration x86/of: Replace printk(KERN_LVL) with pr_lvl() dt-bindings: x86: apic: Introduce new optional bool property for lapic dt-bindings: x86: apic: Convert Intel's APIC bindings to YAML schema x86/of: Remove unused early_init_dt_add_memory_arch() x86/apic: Handle no CONFIG_X86_X2APIC on systems with x2APIC enabled by BIOS
2022-12-05x86/apic/msi: Enable PCI/IMSThomas Gleixner
Enable IMS in the domain init and allocation mapping code, but do not enable it on the vector domain as discussed in various threads on LKML. The interrupt remap domains can expand this setting like they do with PCI multi MSI. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124232327.022658817@linutronix.de
2022-12-05x86/apic/msi: Remove arch_create_remap_msi_irq_domain()Thomas Gleixner
and related code which is not longer required now that the interrupt remap code has been converted to MSI parent domains. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124232326.267353814@linutronix.de
2022-12-05iommu/amd: Switch to MSI base domainsThomas Gleixner
Remove the global PCI/MSI irqdomain implementation and provide the required MSI parent ops so the PCI/MSI code can detect the new parent and setup per device domains. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124232326.209212272@linutronix.de
2022-12-05iommu/vt-d: Switch to MSI parent domainsThomas Gleixner
Remove the global PCI/MSI irqdomain implementation and provide the required MSI parent ops so the PCI/MSI code can detect the new parent and setup per device domains. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124232326.151226317@linutronix.de
2022-12-05x86/apic/vector: Provide MSI parent domainThomas Gleixner
Enable MSI parent domain support in the x86 vector domain and fixup the checks in the iommu implementations to check whether device::msi::domain is the default MSI parent domain. That keeps the existing logic to protect e.g. devices behind VMD working. The interrupt remap PCI/MSI code still works because the underlying vector domain still provides the same functionality. None of the other x86 PCI/MSI, e.g. XEN and HyperV, implementations are affected either. They still work the same way both at the low level and the PCI/MSI implementations they provide. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124232326.034672592@linutronix.de
2022-12-05genirq/msi: Move IRQ_DOMAIN_MSI_NOMASK_QUIRK to MSI flagsThomas Gleixner
It's truly a MSI only flag and for the upcoming per device MSI domains this must be in the MSI flags so it can be set during domain setup without exposing this quirk outside of x86. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124230313.454246167@linutronix.de
2022-12-02x86/apic: Handle no CONFIG_X86_X2APIC on systems with x2APIC enabled by BIOSMateusz Jończyk
A kernel that was compiled without CONFIG_X86_X2APIC was unable to boot on platforms that have x2APIC already enabled in the BIOS before starting the kernel. The kernel was supposed to panic with an approprite error message in validate_x2apic() due to the missing X2APIC support. However, validate_x2apic() was run too late in the boot cycle, and the kernel tried to initialize the APIC nonetheless. This resulted in an earlier panic in setup_local_APIC() because the APIC was not registered. In my experiments, a panic message in setup_local_APIC() was not visible in the graphical console, which resulted in a hang with no indication what has gone wrong. Instead of calling panic(), disable the APIC, which results in a somewhat working system with the PIC only (and no SMP). This way the user is able to diagnose the problem more easily. Disabling X2APIC mode is not an option because it's impossible on systems with locked x2APIC. The proper place to disable the APIC in this case is in check_x2apic(), which is called early from setup_arch(). Doing this in __apic_intr_mode_select() is too late. Make check_x2apic() unconditionally available and remove the empty stub. Reported-by: Paul Menzel <pmenzel@molgen.mpg.de> Reported-by: Robert Elliott (Servers) <elliott@hpe.com> Signed-off-by: Mateusz Jończyk <mat.jonczyk@o2.pl> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/lkml/d573ba1c-0dc4-3016-712a-cc23a8a33d42@molgen.mpg.de Link: https://lore.kernel.org/lkml/20220911084711.13694-3-mat.jonczyk@o2.pl Link: https://lore.kernel.org/all/20221129215008.7247-1-mat.jonczyk@o2.pl
2022-11-17x86/apic: Remove X86_IRQ_ALLOC_CONTIGUOUS_VECTORSThomas Gleixner
Now that the PCI/MSI core code does early checking for multi-MSI support X86_IRQ_ALLOC_CONTIGUOUS_VECTORS is not required anymore. Remove the flag and rely on MSI_FLAG_MULTI_PCI_MSI. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20221111122015.865042356@linutronix.de
2022-08-31x86/apic: Don't disable x2APIC if lockedDaniel Sneddon
The APIC supports two modes, legacy APIC (or xAPIC), and Extended APIC (or x2APIC). X2APIC mode is mostly compatible with legacy APIC, but it disables the memory-mapped APIC interface in favor of one that uses MSRs. The APIC mode is controlled by the EXT bit in the APIC MSR. The MMIO/xAPIC interface has some problems, most notably the APIC LEAK [1]. This bug allows an attacker to use the APIC MMIO interface to extract data from the SGX enclave. Introduce support for a new feature that will allow the BIOS to lock the APIC in x2APIC mode. If the APIC is locked in x2APIC mode and the kernel tries to disable the APIC or revert to legacy APIC mode a GP fault will occur. Introduce support for a new MSR (IA32_XAPIC_DISABLE_STATUS) and handle the new locked mode when the LEGACY_XAPIC_DISABLED bit is set by preventing the kernel from trying to disable the x2APIC. On platforms with the IA32_XAPIC_DISABLE_STATUS MSR, if SGX or TDX are enabled the LEGACY_XAPIC_DISABLED will be set by the BIOS. If legacy APIC is required, then it SGX and TDX need to be disabled in the BIOS. [1]: https://aepicleak.com/aepicleak.pdf Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Link: https://lkml.kernel.org/r/20220816231943.1152579-1-daniel.sneddon@linux.intel.com
2022-08-07Merge tag 'mm-nonmm-stable-2022-08-06-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc updates from Andrew Morton: "Updates to various subsystems which I help look after. lib, ocfs2, fatfs, autofs, squashfs, procfs, etc. A relatively small amount of material this time" * tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits) scripts/gdb: ensure the absolute path is generated on initial source MAINTAINERS: kunit: add David Gow as a maintainer of KUnit mailmap: add linux.dev alias for Brendan Higgins mailmap: update Kirill's email profile: setup_profiling_timer() is moslty not implemented ocfs2: fix a typo in a comment ocfs2: use the bitmap API to simplify code ocfs2: remove some useless functions lib/mpi: fix typo 'the the' in comment proc: add some (hopefully) insightful comments bdi: remove enum wb_congested_state kernel/hung_task: fix address space of proc_dohung_task_timeout_secs lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t() squashfs: support reading fragments in readahead call squashfs: implement readahead squashfs: always build "file direct" version of page actor Revert "squashfs: provide backing_dev_info in order to disable read-ahead" fs/ocfs2: Fix spelling typo in comment ia64: old_rr4 added under CONFIG_HUGETLB_PAGE proc: fix test for "vsyscall=xonly" boot option ...
2022-07-29profile: setup_profiling_timer() is moslty not implementedBen Dooks
The setup_profiling_timer() is mostly un-implemented by many architectures. In many places it isn't guarded by CONFIG_PROFILE which is needed for it to be used. Make it a weak symbol in kernel/profile.c and remove the 'return -EINVAL' implementations from the kenrel. There are a couple of architectures which do return 0 from the setup_profiling_timer() function but they don't seem to do anything else with it. To keep the /proc compatibility for now, leave these for a future update or removal. On ARM, this fixes the following sparse warning: arch/arm/kernel/smp.c:793:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static? Link: https://lkml.kernel.org/r/20220721195509.418205-1-ben-linux@fluff.org Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-24KVM: x86: lapic: Rename [GET/SET]_APIC_DEST_FIELD to [GET/SET]_XAPIC_DEST_FIELDSuravee Suthikulpanit
To signify that the macros only support 8-bit xAPIC destination ID. Suggested-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220519102709.24125-3-suravee.suthikulpanit@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-23Merge tag 'x86_misc_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 updates from Borislav Petkov: "A variety of fixes which don't fit any other tip bucket: - Remove unnecessary function export - Correct asm constraint - Fix __setup handlers retval" * tag 'x86_misc_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Cleanup the control_va_addr_alignment() __setup handler x86: Fix return value of __setup handlers x86/delay: Fix the wrong asm constraint in delay_loop() x86/amd_nb: Unexport amd_cache_northbridges()
2022-05-23Merge tag 'x86_apic_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 APIC updates from Borislav Petkov: - Always do default APIC routing setup so that cpumasks are properly allocated and are present when later accessed ("nosmp" and x2APIC) - Clarify the bit overlap between an old APIC and a modern, integrated one * tag 'x86_apic_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Do apic driver probe for "nosmp" use case x86/apic: Clarify i82489DX bit overlap in APIC_LVT0
2022-05-23Merge tag 'x86_platform_for_v5.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Borislav Petkov: - A couple of changes enabling SGI UV5 support * tag 'x86_platform_for_v5.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform/uv: Log gap hole end size x86/platform/uv: Update TSC sync state for UV5 x86/platform/uv: Update NMI Handler for UV5
2022-05-04x86: Fix return value of __setup handlersRandy Dunlap
__setup() handlers should return 1 to obsolete_checksetup() in init/main.c to indicate that the boot option has been handled. A return of 0 causes the boot option/value to be listed as an Unknown kernel parameter and added to init's (limited) argument (no '=') or environment (with '=') strings. So return 1 from these x86 __setup handlers. Examples: Unknown kernel command line parameters "apicpmtimer BOOT_IMAGE=/boot/bzImage-517rc8 vdso=1 ring3mwait=disable", will be passed to user space. Run /sbin/init as init process with arguments: /sbin/init apicpmtimer with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc8 vdso=1 ring3mwait=disable Fixes: 2aae950b21e4 ("x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu") Fixes: 77b52b4c5c66 ("x86: add "debugpat" boot option") Fixes: e16fd002afe2 ("x86/cpufeature: Enable RING3MWAIT for Knights Landing") Fixes: b8ce33590687 ("x86_64: convert to clock events") Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Link: https://lore.kernel.org/r/20220314012725.26661-1-rdunlap@infradead.org
2022-05-01x86/apic: Do apic driver probe for "nosmp" use caseKuppuswamy Sathyanarayanan
For the "nosmp" use case, the APIC initialization code selects "APIC_SYMMETRIC_IO_NO_ROUTING" as the default interrupt mode and avoids probing APIC drivers. This works well for the default APIC modes, but for the x2APIC case the probe function is required to allocate the cluster_hotplug mask. So in the APIC_SYMMETRIC_IO_NO_ROUTING case when the x2APIC is initialized it dereferences a NULL pointer and the kernel crashes. This was observed on a TDX platform where x2APIC is enabled and "nosmp" command line option is allowed. To fix this issue, probe APIC drivers via default_setup_apic_routing() for the APIC_SYMMETRIC_IO_NO_ROUTING interrupt mode too. Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/r/a64f864e1114bcd63593286aaf61142cfce384ea.1650076869.git.sathyanarayanan.kuppuswamy@intel.com
2022-04-13x86/apic: Clarify i82489DX bit overlap in APIC_LVT0Thomas Gleixner
Daniel stumbled over the bit overlap of the i82498DX external APIC and the TSC deadline timer configuration bit in modern APICs, which is neither documented in the code nor in the current SDM. Maciej provided links to the original i82489DX/486 documentation. See Link. Remove the i82489DX macro maze, use a i82489DX specific define in the apic code and document the overlap in a comment. Reported-by: Daniel Vacek <neelx@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/87ee22f3ci.ffs@tglx
2022-04-07x86/tdx/ioapic: Add shared bit for IOAPIC base addressIsaku Yamahata
The kernel interacts with each bare-metal IOAPIC with a special MMIO page. When running under KVM, the guest's IOAPICs are emulated by KVM. When running as a TDX guest, the guest needs to mark each IOAPIC mapping as "shared" with the host. This ensures that TDX private protections are not applied to the page, which allows the TDX host emulation to work. ioremap()-created mappings such as virtio will be marked as shared by default. However, the IOAPIC code does not use ioremap() and instead uses the fixmap mechanism. Introduce a special fixmap helper just for the IOAPIC code. Ensure that it marks IOAPIC pages as "shared". This replaces set_fixmap_nocache() with __set_fixmap() since __set_fixmap() allows custom 'prot' values. AMD SEV gets IOAPIC pages shared because FIXMAP_PAGE_NOCACHE has _ENC bit clear. TDX has to set bit to share the page with the host. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20220405232939.73860-29-kirill.shutemov@linux.intel.com
2022-04-07x86/acpi/x86/boot: Add multiprocessor wake-up supportKuppuswamy Sathyanarayanan
Secondary CPU startup is currently performed with something called the "INIT/SIPI protocol". This protocol requires assistance from VMMs to boot guests. As should be a familiar story by now, that support can not be provded to TDX guests because TDX VMMs are not trusted by guests. To remedy this situation a new[1] "Multiprocessor Wakeup Structure" has been added to to an existing ACPI table (MADT). This structure provides the physical address of a "mailbox". A write to the mailbox then steers the secondary CPU to the boot code. Add ACPI MADT wake structure parsing support and wake support. Use this support to wake CPUs whenever it is present instead of INIT/SIPI. While this structure can theoretically be used on 32-bit kernels, there are no 32-bit TDX guest kernels. It has not been tested and can not practically *be* tested on 32-bit. Make it 64-bit only. 1. Details about the new structure can be found in ACPI v6.4, in the "Multiprocessor Wakeup Structure" section. Co-developed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lkml.kernel.org/r/20220405232939.73860-22-kirill.shutemov@linux.intel.com
2022-04-07x86/platform/uv: Log gap hole end sizeMike Travis
Show value of gap end in the kernel log which equates to number of physical address bits used by system. Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Steve Wahl <steve.wahl@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20220406195149.228164-4-steve.wahl@hpe.com
2022-04-07x86/platform/uv: Update TSC sync state for UV5Mike Travis
The UV5 platform synchronizes the TSCs among all chassis, and will not proceed to OS boot without achieving synchronization. Previous UV platforms provided a register indicating successful synchronization. This is no longer available on UV5. On this platform TSC_ADJUST should not be reset by the kernel. Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Steve Wahl <steve.wahl@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dimitri Sivanich <dimitri.sivanich@hpe.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20220406195149.228164-3-steve.wahl@hpe.com
2022-01-23Merge tag 'bitmap-5.17-rc1' of git://github.com/norov/linuxLinus Torvalds
Pull bitmap updates from Yury Norov: - introduce for_each_set_bitrange() - use find_first_*_bit() instead of find_next_*_bit() where possible - unify for_each_bit() macros * tag 'bitmap-5.17-rc1' of git://github.com/norov/linux: vsprintf: rework bitmap_list_string lib: bitmap: add performance test for bitmap_print_to_pagebuf bitmap: unify find_bit operations mm/percpu: micro-optimize pcpu_is_populated() Replace for_each_*_bit_from() with for_each_*_bit() where appropriate find: micro-optimize for_each_{set,clear}_bit() include/linux: move for_each_bit() macros from bitops.h to find.h cpumask: replace cpumask_next_* with cpumask_first_* where appropriate tools: sync tools/bitmap with mother linux all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate cpumask: use find_first_and_bit() lib: add find_first_and_bit() arch: remove GENERIC_FIND_FIRST_BIT entirely include: move find.h from asm_generic to linux bitops: move find_bit_*_le functions from le.h to find.h bitops: protect find_first_{,zero}_bit properly
2022-01-15Replace for_each_*_bit_from() with for_each_*_bit() where appropriateYury Norov
A couple of kernel functions call for_each_*_bit_from() with start bit equal to 0. Replace them with for_each_*_bit(). No functional changes, but might improve on readability. Signed-off-by: Yury Norov <yury.norov@gmail.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2021-12-16x86/apic/msi: Use PCI device MSI propertyThomas Gleixner
instead of fiddling with MSI descriptors. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20211210221813.372357371@linutronix.de
2021-12-09PCI/MSI: Make arch_restore_msi_irqs() less horrible.Thomas Gleixner
Make arch_restore_msi_irqs() return a boolean which indicates whether the core code should restore the MSI message or not. Get rid of the indirection in x86. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # PCI Link: https://lore.kernel.org/r/20211206210224.485668098@linutronix.de
2021-12-09genirq/msi, treewide: Use a named struct for PCI/MSI attributesThomas Gleixner
The unnamed struct sucks and is in the way of further cleanups. Stick the PCI related MSI data into a real data structure and cleanup all users. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Kalle Valo <kvalo@codeaurora.org> Link: https://lore.kernel.org/r/20211206210224.374863119@linutronix.de
2021-10-29x86/apic: Reduce cache line misses in __x2apic_send_IPI_mask()Eric Dumazet
Using per-cpu storage for @x86_cpu_to_logical_apicid is not optimal. Broadcast IPI will need at least one cache line per cpu to access this field. __x2apic_send_IPI_mask() is using standard bitmask operators. By converting x86_cpu_to_logical_apicid to an array, we divide by 16x number of needed cache lines, because we find 16 values per cache line. CPU prefetcher can kick nicely. Also move @cluster_masks to READ_MOSTLY section to avoid false sharing. Tested on a dual socket host with 256 cpus, cost for a full broadcast is now 11 usec instead of 33 usec. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20211007143556.574911-1-eric.dumazet@gmail.com
2021-08-30Merge tag 'x86-irq-2021-08-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 PIRQ updates from Thomas Gleixner: "A set of updates to support port 0x22/0x23 based PCI configuration space which can be found on various ALi chipsets and is also available on older Intel systems which expose a PIRQ router. While the Intel support is more or less nostalgia, the ALi chips are still in use on popular embedded boards used for routers" * tag 'x86-irq-2021-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Fix typo s/ECLR/ELCR/ for the PIC register x86: Avoid magic number with ELCR register accesses x86/PCI: Add support for the Intel 82426EX PIRQ router x86/PCI: Add support for the Intel 82374EB/82374SB (ESC) PIRQ router x86/PCI: Add support for the ALi M1487 (IBC) PIRQ router x86: Add support for 0x22/0x23 port I/O configuration space
2021-08-10x86: Avoid magic number with ELCR register accessesMaciej W. Rozycki
Define PIC_ELCR1 and PIC_ELCR2 macros for accesses to the ELCR registers implemented by many chipsets in their embedded 8259A PIC cores, avoiding magic numbers that are difficult to handle, and complementing the macros we already have for registers originally defined with discrete 8259A PIC implementations. No functional change. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2107200237300.9461@angie.orcam.me.uk
2021-08-10x86: Add support for 0x22/0x23 port I/O configuration spaceMaciej W. Rozycki
Define macros and accessors for the configuration space addressed indirectly with an index register and a data register at the port I/O locations of 0x22 and 0x23 respectively. This space is defined by the Intel MultiProcessor Specification for the IMCR register used to switch between the PIC and the APIC mode[1], by Cyrix processors for their configuration[2][3], and also some chipsets. Given the lack of atomicity with the indirect addressing a spinlock is required to protect accesses, although for Cyrix processors it is enough if accesses are executed with interrupts locally disabled, because the registers are local to the accessing CPU, and IMCR is only ever poked at by the BSP and early enough for interrupts not to have been configured yet. Therefore existing code does not have to change or use the new spinlock and neither it does. Put the spinlock in a library file then, so that it does not get pulled unnecessarily for configurations that do not refer it. Convert Cyrix accessors to wrappers so as to retain the brevity and clarity of the `getCx86' and `setCx86' calls. References: [1] "MultiProcessor Specification", Version 1.4, Intel Corporation, Order Number: 242016-006, May 1997, Section 3.6.2.1 "PIC Mode", pp. 3-7, 3-8 [2] "5x86 Microprocessor", Cyrix Corporation, Order Number: 94192-00, July 1995, Section 2.3.2.4 "Configuration Registers", p. 2-23 [3] "6x86 Processor", Cyrix Corporation, Order Number: 94175-01, March 1996, Section 2.4.4 "6x86 Configuration Registers", p. 2-23 Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2107182353140.9461@angie.orcam.me.uk
2021-08-10x86/msi: Force affinity setup before startupThomas Gleixner
The X86 MSI mechanism cannot handle interrupt affinity changes safely after startup other than from an interrupt handler, unless interrupt remapping is enabled. The startup sequence in the generic interrupt code violates that assumption. Mark the irq chips with the new IRQCHIP_AFFINITY_PRE_STARTUP flag so that the default interrupt setting happens before the interrupt is started up for the first time. While the interrupt remapping MSI chip does not require this, there is no point in treating it differently as this might spare an interrupt to a CPU which is not in the default affinity mask. For the non-remapping case go to the direct write path when the interrupt is not yet started similar to the not yet activated case. Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.886722080@linutronix.de
2021-08-10x86/ioapic: Force affinity setup before startupThomas Gleixner
The IO/APIC cannot handle interrupt affinity changes safely after startup other than from an interrupt handler. The startup sequence in the generic interrupt code violates that assumption. Mark the irq chip with the new IRQCHIP_AFFINITY_PRE_STARTUP flag so that the default interrupt setting happens before the interrupt is started up for the first time. Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.832143400@linutronix.de
2021-05-29x86/apic: Mark _all_ legacy interrupts when IO/APIC is missingThomas Gleixner
PIC interrupts do not support affinity setting and they can end up on any online CPU. Therefore, it's required to mark the associated vectors as system-wide reserved. Otherwise, the corresponding irq descriptors are copied to the secondary CPUs but the vectors are not marked as assigned or reserved. This works correctly for the IO/APIC case. When the IO/APIC is disabled via config, kernel command line or lack of enumeration then all legacy interrupts are routed through the PIC, but nothing marks them as system-wide reserved vectors. As a consequence, a subsequent allocation on a secondary CPU can result in allocating one of these vectors, which triggers the BUG() in apic_update_vector() because the interrupt descriptor slot is not empty. Imran tried to work around that by marking those interrupts as allocated when a CPU comes online. But that's wrong in case that the IO/APIC is available and one of the legacy interrupts, e.g. IRQ0, has been switched to PIC mode because then marking them as allocated will fail as they are already marked as system vectors. Stay consistent and update the legacy vectors after attempting IO/APIC initialization and mark them as system vectors in case that no IO/APIC is available. Fixes: 69cde0004a4b ("x86/vector: Use matrix allocator for vector assignment") Reported-by: Imran Khan <imran.f.khan@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20210519233928.2157496-1-imran.f.khan@oracle.com
2021-04-26Merge tag 'x86-apic-2021-04-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic update from Thomas Gleixner: "A single commit to make the vector allocation code more resilent against an accidental allocation attempt for IRQ2" * tag 'x86-apic-2021-04-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vector: Add a sanity check to prevent IRQ2 allocations
2021-04-26Merge tag 'x86_platform_for_v5.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Borislav Petkov: "A bunch of SGI UV improvements, fixes and cleanups" * tag 'x86_platform_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform/uv: Remove dead !CONFIG_KEXEC_CORE code x86/platform/uv: Fix !KEXEC build failure x86/platform/uv: Add more to secondary CPU kdump info x86/platform/uv: Use x2apic enabled bit as set by BIOS to indicate APIC mode x86/platform/uv: Set section block size for hubless architectures x86/platform/uv: Fix indentation warning in Documentation/ABI/testing/sysfs-firmware-sgi_uv
2021-04-16x86/platform/uv: Use x2apic enabled bit as set by BIOS to indicate APIC modeMike Travis
BIOS now sets the x2apic enabled bit (and the ACPI table) for extended APIC modes. Use that bit to indicate if extended mode is set. [ bp: Fixup subject prefix, merge subsequent fix https://lkml.kernel.org/r/20210415220626.223955-1-mike.travis@hpe.com ] Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210408160047.1703-1-mike.travis@hpe.com
2021-03-30x86/vector: Add a sanity check to prevent IRQ2 allocationsThomas Gleixner
To prevent another incidental removal of the IRQ2 ignore logic in the IO/APIC code going unnoticed add a sanity check. Add some commentry at the other place which ignores IRQ2 while at it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210318192819.795280387@linutronix.de
2021-03-21Merge branch 'linus' into x86/cleanups, to resolve conflictIngo Molnar
Conflicts: arch/x86/kernel/kprobes/ftrace.c Signed-off-by: Ingo Molnar <mingo@kernel.org>