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2020-11-13x86/platform/uv: Fix copied UV5 output archtypeMike Travis1-3/+3
A test shows that the output contains a space: # cat /proc/sgi_uv/archtype NSGI4 U/UVX Remove that embedded space by copying the "trimmed" buffer instead of the untrimmed input character list. Use sizeof to remove size dependency on copy out length. Increase output buffer size by one character just in case BIOS sends an 8 character string for archtype. Fixes: 1e61f5a95f19 ("Add and decode Arch Type in UVsystab") Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-11-07x86/platform/uv: Recognize UV5 hubless system identifierMike Travis1-3/+10
Testing shows a problem in that UV5 hubless systems were not being recognized. Add them to the list of OEM IDs checked. Fixes: 6c7794423a998 ("Add UV5 direct references") Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-11-07x86/platform/uv: Remove spaces from OEM IDsMike Travis1-0/+3
Testing shows that trailing spaces caused problems with the OEM_ID and the OEM_TABLE_ID. One being that the OEM_ID would not string compare correctly. Another the OEM_ID and OEM_TABLE_ID would be concatenated in the printout. Remove any trailing spaces. Fixes: 1e61f5a95f191 ("Add and decode Arch Type in UVsystab") Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-11-07x86/platform/uv: Fix missing OEM_TABLE_IDMike Travis1-2/+5
Testing shows a problem in that the OEM_TABLE_ID was missing for hubless systems. This is used to determine the APIC type (legacy or extended). Add the OEM_TABLE_ID to the early hubless processing. Fixes: 1e61f5a95f191 ("Add and decode Arch Type in UVsystab") Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-10-12Merge tag 'x86-irq-2020-10-12' of ↵Linus Torvalds6-127/+77
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 irq updates from Thomas Gleixner: "Surgery of the MSI interrupt handling to prepare the support of upcoming devices which require non-PCI based MSI handling: - Cleanup historical leftovers all over the place - Rework the code to utilize more core functionality - Wrap XEN PCI/MSI interrupts into an irqdomain to make irqdomain assignment to PCI devices possible. - Assign irqdomains to PCI devices at initialization time which allows to utilize the full functionality of hierarchical irqdomains. - Remove arch_.*_msi_irq() functions from X86 and utilize the irqdomain which is assigned to the device for interrupt management. - Make the arch_.*_msi_irq() support conditional on a config switch and let the last few users select it" * tag 'x86-irq-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) PCI: MSI: Fix Kconfig dependencies for PCI_MSI_ARCH_FALLBACKS x86/apic/msi: Unbreak DMAR and HPET MSI iommu/amd: Remove domain search for PCI/MSI iommu/vt-d: Remove domain search for PCI/MSI[X] x86/irq: Make most MSI ops XEN private x86/irq: Cleanup the arch_*_msi_irqs() leftovers PCI/MSI: Make arch_.*_msi_irq[s] fallbacks selectable x86/pci: Set default irq domain in pcibios_add_device() iommm/amd: Store irq domain in struct device iommm/vt-d: Store irq domain in struct device x86/xen: Wrap XEN MSI management into irqdomain irqdomain/msi: Allow to override msi_domain_alloc/free_irqs() x86/xen: Consolidate XEN-MSI init x86/xen: Rework MSI teardown x86/xen: Make xen_msi_init() static and rename it to xen_hvm_msi_init() PCI/MSI: Provide pci_dev_has_special_msi_domain() helper PCI_vmd_Mark_VMD_irqdomain_with_DOMAIN_BUS_VMD_MSI irqdomain/msi: Provide DOMAIN_BUS_VMD_MSI x86/irq: Initialize PCI/MSI domain at PCI init time x86/pci: Reducde #ifdeffery in PCI init code ...
2020-10-07x86/platform/uv: Update Copyrights to conform to HPE standardsMike Travis1-0/+1
Add Copyrights to those files that have been updated for UV5 changes. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Update UV5 TSC checkingMike Travis1-14/+10
Update check of BIOS TSC sync status to include both possible "invalid" states provided by newer UV5 BIOS. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Update node present countingMike Travis1-7/+19
The changes in the UV5 arch shrunk the NODE PRESENT table to just 2x64 entries (128 total) so are in to 64 bit MMRs instead of a depth of 64 bits in an array. Adjust references when counting up the nodes present. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Update UV5 MMR references in UV GRUMike Travis1-6/+24
Make modifications to the GRU mappings to accommodate changes for UV5. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Adjust GAM MMR references affected by UV5 updatesMike Travis1-5/+25
Make modifications to the GAM MMR mappings to accommodate changes for UV5. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Update MMIOH references based on new UV5 MMRsMike Travis1-68/+144
Make modifications to the MMIOH mappings to accommodate changes for UV5. [ Fix W=1 build warnings. ] Reported-by: kernel test robot <[email protected]> Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Add and decode Arch Type in UVsystabMike Travis1-19/+116
When the UV BIOS starts the kernel it passes the UVsystab info struct to the kernel which contains information elements more specific than ACPI, and generally pertinent only to the MMRs. These are read only fields so information is passed one way only. A new field starting with UV5 is the UV architecture type so the ACPI OEM_ID field can be used for other purposes going forward. The UV Arch Type selects the entirety of the MMRs available, with their addresses and fields defined in uv_mmrs.h. Reported-by: kernel test robot <[email protected]> Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Add UV5 direct referencesMike Travis1-27/+70
Add new references to UV5 (and UVY class) system MMR addresses and fields primarily caused by the expansion from 46 to 52 bits of physical memory address. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Update UV MMRs for UV5Mike Travis1-112/+155
Update UV MMRs in uv_mmrs.h for UV5 based on Verilog output from the UV Hub hardware design files. This is the next UV architecture with a new class (UVY) being defined for 52 bit physical address masks. Uses a bitmask for UV arch identification so a single test can cover multiple versions. Includes other adjustments to match the uv_mmrs.h file to keep from encountering compile errors. New UV5 functionality is added in the patches that follow. [ Fix W=1 build warnings. ] Reported-by: kernel test robot <[email protected]> Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Steve Wahl <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-10-07x86/platform/uv: Remove SCIR MMR references for UV systemsMike Travis1-82/+0
UV class systems no longer use System Controller for monitoring of CPU activity provided by this driver. Other methods have been developed for BIOS and the management controller (BMC). Remove that supporting code. Signed-off-by: Mike Travis <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Dimitri Sivanich <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-09-27x86/apic/msi: Unbreak DMAR and HPET MSIThomas Gleixner1-0/+2
Switching the DMAR and HPET MSI code to use the generic MSI domain ops missed to add the flag which tells the core code to update the domain operations with the defaults. As a consequence the core code crashes when an interrupt in one of those domains is allocated. Add the missing flags. Fixes: 9006c133a422 ("x86/msi: Use generic MSI domain ops") Reported-by: Qian Cai <[email protected]> Reported-by: Peter Zijlstra <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-23x86/ioapic: Unbreak check_timer()Thomas Gleixner1-0/+1
Several people reported in the kernel bugzilla that between v4.12 and v4.13 the magic which works around broken hardware and BIOSes to find the proper timer interrupt delivery mode stopped working for some older affected platforms which need to fall back to ExtINT delivery mode. The reason is that the core code changed to keep track of the masked and disabled state of an interrupt line more accurately to avoid the expensive hardware operations. That broke an assumption in i8259_make_irq() which invokes disable_irq_nosync(); irq_set_chip_and_handler(); enable_irq(); Up to v4.12 this worked because enable_irq() unconditionally unmasked the interrupt line, but after the state tracking improvements this is not longer the case because the IO/APIC uses lazy disabling. So the line state is unmasked which means that enable_irq() does not call into the new irq chip to unmask it. In principle this is a shortcoming of the core code, but it's more than unclear whether the core code should try to reset state. At least this cannot be done unconditionally as that would break other existing use cases where the chip type is changed, e.g. when changing the trigger type, but the callers expect the state to be preserved. As the way how check_timer() is switching the delivery modes is truly unique, the obvious fix is to simply unmask the i8259 manually after changing the mode to ExtINT delivery and switching the irq chip to the legacy PIC. Note, that the fixes tag is not really precise, but identifies the commit which broke the assumptions in the IO/APIC and i8259 code and that's the kernel version to which this needs to be backported. Fixes: bf22ff45bed6 ("genirq: Avoid unnecessary low level irq function calls") Reported-by: [email protected] Reported-by: [email protected] Reported-by: [email protected] Reported-by: [email protected] Reported-by: [email protected] Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: [email protected] Tested-by: [email protected] Cc: [email protected] Link: https://bugzilla.kernel.org/show_bug.cgi?id=197769
2020-09-16x86/irq: Cleanup the arch_*_msi_irqs() leftoversThomas Gleixner1-22/+0
Get rid of all the gunk and remove the 'select PCI_MSI_ARCH_FALLBACK' from the x86 Kconfig so the weak functions in the PCI core are replaced by stubs which emit a warning, which ensures that any fail to set the irq domain pointer results in a warning when the device is used. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/pci: Set default irq domain in pcibios_add_device()Thomas Gleixner1-1/+1
Now that interrupt remapping sets the irqdomain pointer when a PCI device is added it's possible to store the default irq domain in the device struct in pcibios_add_device(). If the bus to which a device is connected has an irq domain associated then this domain is used otherwise the default domain (PCI/MSI native or XEN PCI/MSI) is used. Using the bus domain ensures that special MSI bus domains like VMD work. This makes XEN and the non-remapped native case work solely based on the irq domain pointer in struct device for PCI/MSI and allows to remove the arch fallback and make most of the x86_msi ops private to XEN in the next steps. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/irq: Initialize PCI/MSI domain at PCI init timeThomas Gleixner2-14/+19
No point in initializing the default PCI/MSI interrupt domain early and no point to create it when XEN PV/HVM/DOM0 are active. Move the initialization to pci_arch_init() and convert it to init ops so that XEN can override it as XEN has it's own PCI/MSI management. The XEN override comes in a later step. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/irq: Move apic_post_init() invocation to one placeThomas Gleixner3-6/+3
No point to call it from both 32bit and 64bit implementations of default_setup_apic_routing(). Move it to the caller. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/msi: Use generic MSI domain opsThomas Gleixner1-29/+1
pci_msi_get_hwirq() and pci_msi_set_desc are not longer special. Enable the generic MSI domain ops in the core and PCI MSI code unconditionally and get rid of the x86 specific implementations in the X86 MSI code and in the hyperv PCI driver. Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Marc Zyngier <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/msi: Consolidate MSI allocationThomas Gleixner1-4/+3
Convert the interrupt remap drivers to retrieve the pci device from the msi descriptor and use info::hwirq. This is the first step to prepare x86 for using the generic MSI domain ops. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Wei Liu <[email protected]> Acked-by: Joerg Roedel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16PCI/MSI: Rework pci_msi_domain_calc_hwirq()Thomas Gleixner1-1/+1
Retrieve the PCI device from the msi descriptor instead of doing so at the call sites. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Bjorn Helgaas <[email protected]> Acked-by: Marc Zyngier <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/irq: Consolidate DMAR irq allocationThomas Gleixner1-5/+5
None of the DMAR specific fields are required. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86_ioapic_Consolidate_IOAPIC_allocationThomas Gleixner1-35/+35
Move the IOAPIC specific fields into their own struct and reuse the common devid. Get rid of the #ifdeffery as it does not matter at all whether the alloc info is a couple of bytes longer or not. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Wei Liu <[email protected]> Acked-by: Joerg Roedel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/msi: Consolidate HPET allocationThomas Gleixner1-7/+7
None of the magic HPET fields are required in any way. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Joerg Roedel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16iommu/irq_remapping: Consolidate irq domain lookupThomas Gleixner2-2/+2
Now that the iommu implementations handle the X86_*_GET_PARENT_DOMAIN types, consolidate the two getter functions. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Joerg Roedel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/irq: Add allocation type for parent domain retrievalThomas Gleixner2-2/+2
irq_remapping_ir_irq_domain() is used to retrieve the remapping parent domain for an allocation type. irq_remapping_irq_domain() is for retrieving the actual device domain for allocating interrupts for a device. The two functions are similar and can be unified by using explicit modes for parent irq domain retrieval. Add X86_IRQ_ALLOC_TYPE_IOAPIC/HPET_GET_PARENT and use it in the iommu implementations. Drop the parent domain retrieval for PCI_MSI/X as that is unused. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Joerg Roedel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86_irq_Rename_X86_IRQ_ALLOC_TYPE_MSI_to_reflect_PCI_dependencyThomas Gleixner1-3/+3
No functional change. Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Joerg Roedel <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/msi: Remove pointless vcpu_affinity callbackThomas Gleixner1-1/+0
Setting the irq_set_vcpu_affinity() callback to irq_chip_set_vcpu_affinity_parent() is a pointless exercise because the function which utilizes it searchs the domain hierarchy to find a parent domain which has such a callback. Remove the useless indirection. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16x86/msi: Move compose message callback where it belongsThomas Gleixner2-9/+4
Composing the MSI message at the MSI chip level is wrong because the underlying parent domain is the one which knows how the message should be composed for the direct vector delivery or the interrupt remapping table entry. The interrupt remapping aware PCI/MSI chip does that already. Make the direct delivery chip do the same and move the composition of the direct delivery MSI message to the vector domain irq chip. This prepares for the upcoming device MSI support to avoid having architecture specific knowledge in the device MSI domain irq chips. Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-09-16genirq/chip: Use the first chip in irq_chip_compose_msi_msg()Thomas Gleixner1-2/+5
The documentation of irq_chip_compose_msi_msg() claims that with hierarchical irq domains the first chip in the hierarchy which has an irq_compose_msi_msg() callback is chosen. But the code just keeps iterating after it finds a chip with a compose callback. The x86 HPET MSI implementation relies on that behaviour, but that does not make it more correct. The message should always be composed at the domain which manages the underlying resource (e.g. APIC or remap table) because that domain knows about the required layout of the message. On X86 the following hierarchies exist: 1) vector -------- PCI/MSI 2) vector -- IR -- PCI/MSI The vector domain has a different message format than the IR (remapping) domain. So obviously the PCI/MSI domain can't compose the message without having knowledge about the parent domain, which is exactly the opposite of what hierarchical domains want to achieve. X86 actually has two different PCI/MSI chips where #1 has a compose callback and #2 does not. #2 delegates the composition to the remap domain where it belongs, but #1 does it at the PCI/MSI level. For the upcoming device MSI support it's necessary to change this and just let the first domain which can compose the message take care of it. That way the top level chip does not have to worry about it and the device MSI code does not need special knowledge about topologies. It just sets the compose callback to NULL and lets the hierarchy pick the first chip which has one. Due to that the attempt to move the compose callback from the direct delivery PCI/MSI domain to the vector domain made the system fail to boot with interrupt remapping enabled because in the remapping case irq_chip_compose_msi_msg() keeps iterating and choses the compose callback of the vector domain which obviously creates the wrong format for the remap table. Break out of the loop when the first irq chip with a compose callback is found and fixup the HPET code temporarily. That workaround will be removed once the direct delivery compose callback is moved to the place where it belongs in the vector domain. Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Marc Zyngier <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-08-30Merge tag 'x86-urgent-2020-08-30' of ↵Linus Torvalds1-7/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "Three interrupt related fixes for X86: - Move disabling of the local APIC after invoking fixup_irqs() to ensure that interrupts which are incoming are noted in the IRR and not ignored. - Unbreak affinity setting. The rework of the entry code reused the regular exception entry code for device interrupts. The vector number is pushed into the errorcode slot on the stack which is then lifted into an argument and set to -1 because that's regs->orig_ax which is used in quite some places to check whether the entry came from a syscall. But it was overlooked that orig_ax is used in the affinity cleanup code to validate whether the interrupt has arrived on the new target. It turned out that this vector check is pointless because interrupts are never moved from one vector to another on the same CPU. That check is a historical leftover from the time where x86 supported multi-CPU affinities, but not longer needed with the now strict single CPU affinity. Famous last words ... - Add a missing check for an empty cpumask into the matrix allocator. The affinity change added a warning to catch the case where an interrupt is moved on the same CPU to a different vector. This triggers because a condition with an empty cpumask returns an assignment from the allocator as the allocator uses for_each_cpu() without checking the cpumask for being empty. The historical inconsistent for_each_cpu() behaviour of ignoring the cpumask and unconditionally claiming that CPU0 is in the mask struck again. Sigh. plus a new entry into the MAINTAINER file for the HPE/UV platform" * tag 'x86-urgent-2020-08-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/matrix: Deal with the sillyness of for_each_cpu() on UP x86/irq: Unbreak interrupt affinity setting x86/hotplug: Silence APIC only after all interrupts are migrated MAINTAINERS: Add entry for HPE Superdome Flex (UV) maintainers
2020-08-27x86/irq: Unbreak interrupt affinity settingThomas Gleixner1-7/+9
Several people reported that 5.8 broke the interrupt affinity setting mechanism. The consolidation of the entry code reused the regular exception entry code for device interrupts and changed the way how the vector number is conveyed from ptregs->orig_ax to a function argument. The low level entry uses the hardware error code slot to push the vector number onto the stack which is retrieved from there into a function argument and the slot on stack is set to -1. The reason for setting it to -1 is that the error code slot is at the position where pt_regs::orig_ax is. A positive value in pt_regs::orig_ax indicates that the entry came via a syscall. If it's not set to a negative value then a signal delivery on return to userspace would try to restart a syscall. But there are other places which rely on pt_regs::orig_ax being a valid indicator for syscall entry. But setting pt_regs::orig_ax to -1 has a nasty side effect vs. the interrupt affinity setting mechanism, which was overlooked when this change was made. Moving interrupts on x86 happens in several steps. A new vector on a different CPU is allocated and the relevant interrupt source is reprogrammed to that. But that's racy and there might be an interrupt already in flight to the old vector. So the old vector is preserved until the first interrupt arrives on the new vector and the new target CPU. Once that happens the old vector is cleaned up, but this cleanup still depends on the vector number being stored in pt_regs::orig_ax, which is now -1. That -1 makes the check for cleanup: pt_regs::orig_ax == new_vector always false. As a consequence the interrupt is moved once, but then it cannot be moved anymore because the cleanup of the old vector never happens. There would be several ways to convey the vector information to that place in the guts of the interrupt handling, but on deeper inspection it turned out that this check is pointless and a leftover from the old affinity model of X86 which supported multi-CPU affinities. Under this model it was possible that an interrupt had an old and a new vector on the same CPU, so the vector match was required. Under the new model the effective affinity of an interrupt is always a single CPU from the requested affinity mask. If the affinity mask changes then either the interrupt stays on the CPU and on the same vector when that CPU is still in the new affinity mask or it is moved to a different CPU, but it is never moved to a different vector on the same CPU. Ergo the cleanup check for the matching vector number is not required and can be removed which makes the dependency on pt_regs:orig_ax go away. The remaining check for new_cpu == smp_processsor_id() is completely sufficient. If it matches then the interrupt was successfully migrated and the cleanup can proceed. For paranoia sake add a warning into the vector assignment code to validate that the assumption of never moving to a different vector on the same CPU holds. Fixes: 633260fa143 ("x86/irq: Convey vector as argument and not in ptregs") Reported-by: Alex bykov <[email protected]> Reported-by: Avi Kivity <[email protected]> Reported-by: Alexander Graf <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Alexander Graf <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected]
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2-3/+3
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <[email protected]>
2020-08-10Merge tag 'locking-urgent-2020-08-10' of ↵Linus Torvalds8-0/+8
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Thomas Gleixner: "A set of locking fixes and updates: - Untangle the header spaghetti which causes build failures in various situations caused by the lockdep additions to seqcount to validate that the write side critical sections are non-preemptible. - The seqcount associated lock debug addons which were blocked by the above fallout. seqcount writers contrary to seqlock writers must be externally serialized, which usually happens via locking - except for strict per CPU seqcounts. As the lock is not part of the seqcount, lockdep cannot validate that the lock is held. This new debug mechanism adds the concept of associated locks. sequence count has now lock type variants and corresponding initializers which take a pointer to the associated lock used for writer serialization. If lockdep is enabled the pointer is stored and write_seqcount_begin() has a lockdep assertion to validate that the lock is held. Aside of the type and the initializer no other code changes are required at the seqcount usage sites. The rest of the seqcount API is unchanged and determines the type at compile time with the help of _Generic which is possible now that the minimal GCC version has been moved up. Adding this lockdep coverage unearthed a handful of seqcount bugs which have been addressed already independent of this. While generally useful this comes with a Trojan Horse twist: On RT kernels the write side critical section can become preemtible if the writers are serialized by an associated lock, which leads to the well known reader preempts writer livelock. RT prevents this by storing the associated lock pointer independent of lockdep in the seqcount and changing the reader side to block on the lock when a reader detects that a writer is in the write side critical section. - Conversion of seqcount usage sites to associated types and initializers" * tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits) locking/seqlock, headers: Untangle the spaghetti monster locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header x86/headers: Remove APIC headers from <asm/smp.h> seqcount: More consistent seqprop names seqcount: Compress SEQCNT_LOCKNAME_ZERO() seqlock: Fold seqcount_LOCKNAME_init() definition seqlock: Fold seqcount_LOCKNAME_t definition seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g hrtimer: Use sequence counter with associated raw spinlock kvm/eventfd: Use sequence counter with associated spinlock userfaultfd: Use sequence counter with associated spinlock NFSv4: Use sequence counter with associated spinlock iocost: Use sequence counter with associated spinlock raid5: Use sequence counter with associated spinlock vfs: Use sequence counter with associated spinlock timekeeping: Use sequence counter with associated raw spinlock xfrm: policy: Use sequence counters with associated lock netfilter: nft_set_rbtree: Use sequence counter with associated rwlock netfilter: conntrack: Use sequence counter with associated spinlock sched: tasks: Use sequence counter with associated spinlock ...
2020-08-07mm: remove unneeded includes of <asm/pgalloc.h>Mike Rapoport1-1/+0
Patch series "mm: cleanup usage of <asm/pgalloc.h>" Most architectures have very similar versions of pXd_alloc_one() and pXd_free_one() for intermediate levels of page table. These patches add generic versions of these functions in <asm-generic/pgalloc.h> and enable use of the generic functions where appropriate. In addition, functions declared and defined in <asm/pgalloc.h> headers are used mostly by core mm and early mm initialization in arch and there is no actual reason to have the <asm/pgalloc.h> included all over the place. The first patch in this series removes unneeded includes of <asm/pgalloc.h> In the end it didn't work out as neatly as I hoped and moving pXd_alloc_track() definitions to <asm-generic/pgalloc.h> would require unnecessary changes to arches that have custom page table allocations, so I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local to mm/. This patch (of 8): In most cases <asm/pgalloc.h> header is required only for allocations of page table memory. Most of the .c files that include that header do not use symbols declared in <asm/pgalloc.h> and do not require that header. As for the other header files that used to include <asm/pgalloc.h>, it is possible to move that include into the .c file that actually uses symbols from <asm/pgalloc.h> and drop the include from the header file. The process was somewhat automated using sed -i -E '/[<"]asm\/pgalloc\.h/d' \ $(grep -L -w -f /tmp/xx \ $(git grep -E -l '[<"]asm/pgalloc\.h')) where /tmp/xx contains all the symbols defined in arch/*/include/asm/pgalloc.h. [[email protected]: fix powerpc warning] Signed-off-by: Mike Rapoport <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Pekka Enberg <[email protected]> Acked-by: Geert Uytterhoeven <[email protected]> [m68k] Cc: Abdul Haleem <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Christophe Leroy <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Max Filippov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Satheesh Rajendran <[email protected]> Cc: Stafford Horne <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Matthew Wilcox <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-08-06locking/seqlock, headers: Untangle the spaghetti monsterPeter Zijlstra3-0/+3
By using lockdep_assert_*() from seqlock.h, the spaghetti monster attacked. Attack back by reducing seqlock.h dependencies from two key high level headers: - <linux/seqlock.h>: -Remove <linux/ww_mutex.h> - <linux/time.h>: -Remove <linux/seqlock.h> - <linux/sched.h>: +Add <linux/seqlock.h> The price was to add it to sched.h ... Core header fallout, we add direct header dependencies instead of gaining them parasitically from higher level headers: - <linux/dynamic_queue_limits.h>: +Add <asm/bug.h> - <linux/hrtimer.h>: +Add <linux/seqlock.h> - <linux/ktime.h>: +Add <asm/bug.h> - <linux/lockdep.h>: +Add <linux/smp.h> - <linux/sched.h>: +Add <linux/seqlock.h> - <linux/videodev2.h>: +Add <linux/kernel.h> Arch headers fallout: - PARISC: <asm/timex.h>: +Add <asm/special_insns.h> - SH: <asm/io.h>: +Add <asm/page.h> - SPARC: <asm/timer_64.h>: +Add <uapi/asm/asi.h> - SPARC: <asm/vvar.h>: +Add <asm/processor.h>, <asm/barrier.h> -Remove <linux/seqlock.h> - X86: <asm/fixmap.h>: +Add <asm/pgtable_types.h> -Remove <asm/acpi.h> There's also a bunch of parasitic header dependency fallout in .c files, not listed separately. [ mingo: Extended the changelog, split up & fixed the original patch. ] Co-developed-by: Ingo Molnar <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-08-06x86/headers: Remove APIC headers from <asm/smp.h>Ingo Molnar5-0/+5
The APIC headers are relatively complex and bring in additional header dependencies - while smp.h is a relatively simple header included from high level headers. Remove the dependency and add in the missing #include's in .c files where they gained it indirectly before. Signed-off-by: Ingo Molnar <[email protected]>
2020-08-03Merge tag 'x86-platform-2020-08-03' of ↵Linus Torvalds1-96/+26
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Ingo Molnar: "The biggest change is the removal of SGI UV1 support, which allowed the removal of the legacy EFI old_mmap code as well. This removes quite a bunch of old code & quirks" * tag 'x86-platform-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/efi: Remove unused EFI_UV1_MEMMAP code x86/platform/uv: Remove uv bios and efi code related to EFI_UV1_MEMMAP x86/efi: Remove references to no-longer-used efi_have_uv1_memmap() x86/efi: Delete SGI UV1 detection. x86/platform/uv: Remove efi=old_map command line option x86/platform/uv: Remove vestigial mention of UV1 platform from bios header x86/platform/uv: Remove support for UV1 platform from uv x86/platform/uv: Remove support for uv1 platform from uv_hub x86/platform/uv: Remove support for UV1 platform from uv_bau x86/platform/uv: Remove support for UV1 platform from uv_mmrs x86/platform/uv: Remove support for UV1 platform from x2apic_uv_x x86/platform/uv: Remove support for UV1 platform from uv_tlb x86/platform/uv: Remove support for UV1 platform from uv_time
2020-07-27genirq/affinity: Make affinity setting if activated opt-inThomas Gleixner1-0/+4
John reported that on a RK3288 system the perf per CPU interrupts are all affine to CPU0 and provided the analysis: "It looks like what happens is that because the interrupts are not per-CPU in the hardware, armpmu_request_irq() calls irq_force_affinity() while the interrupt is deactivated and then request_irq() with IRQF_PERCPU | IRQF_NOBALANCING. Now when irq_startup() runs with IRQ_STARTUP_NORMAL, it calls irq_setup_affinity() which returns early because IRQF_PERCPU and IRQF_NOBALANCING are set, leaving the interrupt on its original CPU." This was broken by the recent commit which blocked interrupt affinity setting in hardware before activation of the interrupt. While this works in general, it does not work for this particular case. As contrary to the initial analysis not all interrupt chip drivers implement an activate callback, the safe cure is to make the deferred interrupt affinity setting at activation time opt-in. Implement the necessary core logic and make the two irqchip implementations for which this is required opt-in. In hindsight this would have been the right thing to do, but ... Fixes: baedb87d1b53 ("genirq/affinity: Handle affinity setting on inactive interrupts correctly") Reported-by: John Keeping <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Marc Zyngier <[email protected]> Acked-by: Marc Zyngier <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-07-23irqdomain/treewide: Free firmware node after domain removalJon Derrick1-0/+5
Commit 711419e504eb ("irqdomain: Add the missing assignment of domain->fwnode for named fwnode") unintentionally caused a dangling pointer page fault issue on firmware nodes that were freed after IRQ domain allocation. Commit e3beca48a45b fixed that dangling pointer issue by only freeing the firmware node after an IRQ domain allocation failure. That fix no longer frees the firmware node immediately, but leaves the firmware node allocated after the domain is removed. The firmware node must be kept around through irq_domain_remove, but should be freed it afterwards. Add the missing free operations after domain removal where where appropriate. Fixes: e3beca48a45b ("irqdomain/treewide: Keep firmware node unconditionally allocated") Signed-off-by: Jon Derrick <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Andy Shevchenko <[email protected]> Acked-by: Bjorn Helgaas <[email protected]> # drivers/pci Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-07-17genirq/affinity: Handle affinity setting on inactive interrupts correctlyThomas Gleixner1-17/+5
Setting interrupt affinity on inactive interrupts is inconsistent when hierarchical irq domains are enabled. The core code should just store the affinity and not call into the irq chip driver for inactive interrupts because the chip drivers may not be in a state to handle such requests. X86 has a hacky workaround for that but all other irq chips have not which causes problems e.g. on GIC V3 ITS. Instead of adding more ugly hacks all over the place, solve the problem in the core code. If the affinity is set on an inactive interrupt then: - Store it in the irq descriptors affinity mask - Update the effective affinity to reflect that so user space has a consistent view - Don't call into the irq chip driver This is the core equivalent of the X86 workaround and works correctly because the affinity setting is established in the irq chip when the interrupt is activated later on. Note, that this is only effective when hierarchical irq domains are enabled by the architecture. Doing it unconditionally would break legacy irq chip implementations. For hierarchial irq domains this works correctly as none of the drivers can have a dependency on affinity setting in inactive state by design. Remove the X86 workaround as it is not longer required. Fixes: 02edee152d6e ("x86/apic/vector: Ignore set_affinity call for inactive interrupts") Reported-by: Ali Saidi <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Ali Saidi <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-07-17x86/platform/uv: Remove support for UV1 platform from x2apic_uv_x[email protected]1-96/+26
UV1 is not longer supported. Signed-off-by: Steve Wahl <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
2020-07-14irqdomain/treewide: Keep firmware node unconditionally allocatedThomas Gleixner3-12/+17
Quite some non OF/ACPI users of irqdomains allocate firmware nodes of type IRQCHIP_FWNODE_NAMED or IRQCHIP_FWNODE_NAMED_ID and free them right after creating the irqdomain. The only purpose of these FW nodes is to convey name information. When this was introduced the core code did not store the pointer to the node in the irqdomain. A recent change stored the firmware node pointer in irqdomain for other reasons and missed to notice that the usage sites which do the alloc_fwnode/create_domain/free_fwnode sequence are broken by this. Storing a dangling pointer is dangerous itself, but in case that the domain is destroyed later on this leads to a double free. Remove the freeing of the firmware node after creating the irqdomain from all affected call sites to cure this. Fixes: 711419e504eb ("irqdomain: Add the missing assignment of domain->fwnode for named fwnode") Reported-by: Andy Shevchenko <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Bjorn Helgaas <[email protected]> Acked-by: Marc Zyngier <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
2020-06-13Merge tag 'x86-entry-2020-06-12' of ↵Linus Torvalds3-24/+23
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 entry updates from Thomas Gleixner: "The x86 entry, exception and interrupt code rework This all started about 6 month ago with the attempt to move the Posix CPU timer heavy lifting out of the timer interrupt code and just have lockless quick checks in that code path. Trivial 5 patches. This unearthed an inconsistency in the KVM handling of task work and the review requested to move all of this into generic code so other architectures can share. Valid request and solved with another 25 patches but those unearthed inconsistencies vs. RCU and instrumentation. Digging into this made it obvious that there are quite some inconsistencies vs. instrumentation in general. The int3 text poke handling in particular was completely unprotected and with the batched update of trace events even more likely to expose to endless int3 recursion. In parallel the RCU implications of instrumenting fragile entry code came up in several discussions. The conclusion of the x86 maintainer team was to go all the way and make the protection against any form of instrumentation of fragile and dangerous code pathes enforcable and verifiable by tooling. A first batch of preparatory work hit mainline with commit d5f744f9a2ac ("Pull x86 entry code updates from Thomas Gleixner") That (almost) full solution introduced a new code section '.noinstr.text' into which all code which needs to be protected from instrumentation of all sorts goes into. Any call into instrumentable code out of this section has to be annotated. objtool has support to validate this. Kprobes now excludes this section fully which also prevents BPF from fiddling with it and all 'noinstr' annotated functions also keep ftrace off. The section, kprobes and objtool changes are already merged. The major changes coming with this are: - Preparatory cleanups - Annotating of relevant functions to move them into the noinstr.text section or enforcing inlining by marking them __always_inline so the compiler cannot misplace or instrument them. - Splitting and simplifying the idtentry macro maze so that it is now clearly separated into simple exception entries and the more interesting ones which use interrupt stacks and have the paranoid handling vs. CR3 and GS. - Move quite some of the low level ASM functionality into C code: - enter_from and exit to user space handling. The ASM code now calls into C after doing the really necessary ASM handling and the return path goes back out without bells and whistels in ASM. - exception entry/exit got the equivivalent treatment - move all IRQ tracepoints from ASM to C so they can be placed as appropriate which is especially important for the int3 recursion issue. - Consolidate the declaration and definition of entry points between 32 and 64 bit. They share a common header and macros now. - Remove the extra device interrupt entry maze and just use the regular exception entry code. - All ASM entry points except NMI are now generated from the shared header file and the corresponding macros in the 32 and 64 bit entry ASM. - The C code entry points are consolidated as well with the help of DEFINE_IDTENTRY*() macros. This allows to ensure at one central point that all corresponding entry points share the same semantics. The actual function body for most entry points is in an instrumentable and sane state. There are special macros for the more sensitive entry points, e.g. INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF. They allow to put the whole entry instrumentation and RCU handling into safe places instead of the previous pray that it is correct approach. - The INT3 text poke handling is now completely isolated and the recursion issue banned. Aside of the entry rework this required other isolation work, e.g. the ability to force inline bsearch. - Prevent #DB on fragile entry code, entry relevant memory and disable it on NMI, #MC entry, which allowed to get rid of the nested #DB IST stack shifting hackery. - A few other cleanups and enhancements which have been made possible through this and already merged changes, e.g. consolidating and further restricting the IDT code so the IDT table becomes RO after init which removes yet another popular attack vector - About 680 lines of ASM maze are gone. There are a few open issues: - An escape out of the noinstr section in the MCE handler which needs some more thought but under the aspect that MCE is a complete trainwreck by design and the propability to survive it is low, this was not high on the priority list. - Paravirtualization When PV is enabled then objtool complains about a bunch of indirect calls out of the noinstr section. There are a few straight forward ways to fix this, but the other issues vs. general correctness were more pressing than parawitz. - KVM KVM is inconsistent as well. Patches have been posted, but they have not yet been commented on or picked up by the KVM folks. - IDLE Pretty much the same problems can be found in the low level idle code especially the parts where RCU stopped watching. This was beyond the scope of the more obvious and exposable problems and is on the todo list. The lesson learned from this brain melting exercise to morph the evolved code base into something which can be validated and understood is that once again the violation of the most important engineering principle "correctness first" has caused quite a few people to spend valuable time on problems which could have been avoided in the first place. The "features first" tinkering mindset really has to stop. With that I want to say thanks to everyone involved in contributing to this effort. Special thanks go to the following people (alphabetical order): Alexandre Chartre, Andy Lutomirski, Borislav Petkov, Brian Gerst, Frederic Weisbecker, Josh Poimboeuf, Juergen Gross, Lai Jiangshan, Macro Elver, Paolo Bonzin,i Paul McKenney, Peter Zijlstra, Vitaly Kuznetsov, and Will Deacon" * tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (142 commits) x86/entry: Force rcu_irq_enter() when in idle task x86/entry: Make NMI use IDTENTRY_RAW x86/entry: Treat BUG/WARN as NMI-like entries x86/entry: Unbreak __irqentry_text_start/end magic x86/entry: __always_inline CR2 for noinstr lockdep: __always_inline more for noinstr x86/entry: Re-order #DB handler to avoid *SAN instrumentation x86/entry: __always_inline arch_atomic_* for noinstr x86/entry: __always_inline irqflags for noinstr x86/entry: __always_inline debugreg for noinstr x86/idt: Consolidate idt functionality x86/idt: Cleanup trap_init() x86/idt: Use proper constants for table size x86/idt: Add comments about early #PF handling x86/idt: Mark init only functions __init x86/entry: Rename trace_hardirqs_off_prepare() x86/entry: Clarify irq_{enter,exit}_rcu() x86/entry: Remove DBn stacks x86/entry: Remove debug IDT frobbing x86/entry: Optimize local_db_save() for virt ...
2020-06-11Merge tag 'x86-urgent-2020-06-11' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more x86 updates from Thomas Gleixner: "A set of fixes and updates for x86: - Unbreak paravirt VDSO clocks. While the VDSO code was moved into lib for sharing a subtle check for the validity of paravirt clocks got replaced. While the replacement works perfectly fine for bare metal as the update of the VDSO clock mode is synchronous, it fails for paravirt clocks because the hypervisor can invalidate them asynchronously. Bring it back as an optional function so it does not inflict this on architectures which are free of PV damage. - Fix the jiffies to jiffies64 mapping on 64bit so it does not trigger an ODR violation on newer compilers - Three fixes for the SSBD and *IB* speculation mitigation maze to ensure consistency, not disabling of some *IB* variants wrongly and to prevent a rogue cross process shutdown of SSBD. All marked for stable. - Add yet more CPU models to the splitlock detection capable list !@#%$! - Bring the pr_info() back which tells that TSC deadline timer is enabled. - Reboot quirk for MacBook6,1" * tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Unbreak paravirt VDSO clocks lib/vdso: Provide sanity check for cycles (again) clocksource: Remove obsolete ifdef x86_64: Fix jiffies ODR violation x86/speculation: PR_SPEC_FORCE_DISABLE enforcement for indirect branches. x86/speculation: Prevent rogue cross-process SSBD shutdown x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS. x86/cpu: Add Sapphire Rapids CPU model number x86/split_lock: Add Icelake microserver and Tigerlake CPU models x86/apic: Make TSC deadline timer detection message visible x86/reboot/quirks: Add MacBook6,1 reboot quirk
2020-06-11x86/entry: Convert SMP system vectors to IDTENTRY_SYSVECThomas Gleixner1-3/+2
Convert SMP system vectors to IDTENTRY_SYSVEC: - Implement the C entry point with DEFINE_IDTENTRY_SYSVEC - Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC - Remove the ASM idtentries in 64-bit - Remove the BUILD_INTERRUPT entries in 32-bit - Remove the old prototypes No functional change. Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Acked-by: Andy Lutomirski <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2020-06-11x86/entry: Convert APIC interrupts to IDTENTRY_SYSVECThomas Gleixner1-18/+5
Convert APIC interrupts to IDTENTRY_SYSVEC: - Implement the C entry point with DEFINE_IDTENTRY_SYSVEC - Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC - Remove the ASM idtentries in 64-bit - Remove the BUILD_INTERRUPT entries in 32-bit - Remove the old prototypes No functional change. Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Acked-by: Andy Lutomirski <[email protected]> Link: https://lore.kernel.org/r/[email protected]