BMC/Intel-BMC/linux.git/arch/x86/kernel/apic, branch dev-4.3

x86/irq: Probe for PIC presence before allocating descs for legacy IRQs

2015-12-09T19:34:18+00:00

commit 8c058b0b9c34d8c8d7912880956543769323e2d8 upstream. Commit d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") brought a regression for Hyper-V Gen2 instances. These instances don't have i8259 legacy PIC but they use legacy IRQs for serial port, rtc, and acpi. With this commit included we end up with these IRQs not initialized. Earlier, there was a special workaround for legacy IRQs in mp_map_pin_to_irq() doing mp_irqdomain_map() without looking at nr_legacy_irqs() and now we fail in __irq_domain_alloc_irqs() when irq_domain_alloc_descs() returns -EEXIST. The essence of the issue seems to be that early_irq_init() calls arch_probe_nr_irqs() to figure out the number of legacy IRQs before we probe for i8259 and gets 16. Later when init_8259A() is called we switch to NULL legacy PIC and nr_legacy_irqs() starts to return 0 but we already have 16 descs allocated. Solve the issue by separating i8259 probe from init and calling it in arch_probe_nr_irqs() before we actually use nr_legacy_irqs() information. Fixes: d32932d02e18 ("x86/irq: Convert IOAPIC to use hierarchical irqdomain interfaces") Signed-off-by: Vitaly Kuznetsov Cc: Jiang Liu Cc: K. Y. Srinivasan Link: http://lkml.kernel.org/r/1446543614-3621-1-git-send-email-vkuznets@redhat.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

x86/ioapic: Prevent NULL pointer dereference in setup_ioapic_dest()

2015-10-27T00:18:34+00:00

Commit 4857c91f0d19 changed the way how irq affinity is setup in setup_ioapic_dest() from using the core helper function to unconditionally calling the irq_set_affinity() callback of the underlying irq chip. That results in a NULL pointer dereference for the rare case where the underlying irq chip is lapic_chip which has no irq_set_affinity() callback. lapic_chip is occasionally used for the timer interrupt (irq 0). The fix is simple: Check the availability of the callback instead of calling it unconditionally. Fixes: 4857c91f0d19 "x86/ioapic: Force affinity setting in setup_ioapic_dest()" Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org

x86/ioapic: Disable interrupts when re-routing legacy IRQs

2015-10-16T14:31:24+00:00

A sporadic hang with consequent crash is observed when booting Hyper-V Gen1 guests: Call Trace: [] ? trace_hardirqs_off+0xd/0x10 [] queue_work_on+0x46/0x90 [] ? add_interrupt_randomness+0x176/0x1d0 ... [] ? _raw_spin_unlock_irqrestore+0x3b/0x60 [] __irq_put_desc_unlock+0x1e/0x40 [] irq_modify_status+0xb5/0xd0 [] mp_register_handler+0x4b/0x70 [] mp_irqdomain_alloc+0x1ea/0x2a0 [] irq_domain_alloc_irqs_recursive+0x40/0xa0 [] __irq_domain_alloc_irqs+0x13c/0x2b0 [] alloc_isa_irq_from_domain.isra.1+0xc0/0xe0 [] mp_map_pin_to_irq+0x165/0x2d0 [] pin_2_irq+0x47/0x80 [] setup_IO_APIC+0xfe/0x802 ... [] ? rest_init+0x140/0x140 The issue is easily reproducible with a simple instrumentation: if mdelay(10) is put between mp_setup_entry() and mp_register_handler() calls in mp_irqdomain_alloc() Hyper-V guest always fails to boot when re-routing IRQ0. The issue seems to be caused by the fact that we don't disable interrupts while doing IOPIC programming for legacy IRQs and IRQ0 actually happens. Protect the setup sequence against concurrent interrupts. [ tglx: Make the protection unconditional and not only for legacy interrupts ] Signed-off-by: Vitaly Kuznetsov Cc: Jiang Liu Cc: Yinghai Lu Cc: K. Y. Srinivasan Link: http://lkml.kernel.org/r/1444930943-19336-1-git-send-email-vkuznets@redhat.com Signed-off-by: Thomas Gleixner

Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-18T15:11:42+00:00

Pull irq updates from Thomas Gleixner: "This is a rather large update post rc1 due to the final steps of cleanups and API changes which had to wait for the preparatory patches to hit your tree. - Regression fixes for ARM GIC irqchips - Regression fixes and lockdep anotations for renesas irq chips - The leftovers of the cleanup and preparatory patches which have been ignored by maintainers - Final conversions of the newly merged users of obsolete APIs - Final removal of obsolete APIs - Final removal of ARM artifacts which had been introduced during the conversion of ARM to the generic interrupt code. - Final split of the irq_data into chip specific and common data to reflect the needs of hierarchical irq domains. - Treewide removal of the first argument of interrupt flow handlers, i.e. the irq number, which is not used by the majority of handlers and simple to retrieve from the other argument the irq descriptor. - A few comment updates and build warning fixes" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) arm64: Remove ununsed set_irq_flags ARM: Remove ununsed set_irq_flags sh: Kill off set_irq_flags usage irqchip: Kill off set_irq_flags usage gpu/drm: Kill off set_irq_flags usage genirq: Remove irq argument from irq flow handlers genirq: Move field 'msi_desc' from irq_data into irq_common_data genirq: Move field 'affinity' from irq_data into irq_common_data genirq: Move field 'handler_data' from irq_data into irq_common_data genirq: Move field 'node' from irq_data into irq_common_data irqchip/gic-v3: Use IRQD_FORWARDED_TO_VCPU flag irqchip/gic: Use IRQD_FORWARDED_TO_VCPU flag genirq: Provide IRQD_FORWARDED_TO_VCPU status flag genirq: Simplify irq_data_to_desc() genirq: Remove __irq_set_handler_locked() pinctrl/pistachio: Use irq_set_handler_locked gpio: vf610: Use irq_set_handler_locked powerpc/mpc8xx: Use irq_set_handler_locked() powerpc/ipic: Use irq_set_handler_locked() powerpc/cpm2: Use irq_set_handler_locked() ...

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-17T18:01:34+00:00

Pull x86 fixes from Ingo Molnar: - misc fixes all around the map - block non-root vm86(old) if mmap_min_addr != 0 - two small debuggability improvements - removal of obsolete paravirt op * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform: Fix Geode LX timekeeping in the generic x86 build x86/apic: Serialize LVTT and TSC_DEADLINE writes x86/ioapic: Force affinity setting in setup_ioapic_dest() x86/paravirt: Remove the unused pv_time_ops::get_tsc_khz method x86/ldt: Fix small LDT allocation for Xen x86/vm86: Fix the misleading CONFIG_VM86 Kconfig help text x86/cpu: Print family/model/stepping in hex x86/vm86: Block non-root vm86(old) if mmap_min_addr != 0 x86/alternatives: Make optimize_nops() interrupt safe and synced x86/mm/srat: Print non-volatile flag in SRAT x86/cpufeatures: Enable cpuid for Intel SHA extensions

genirq: Move field 'affinity' from irq_data into irq_common_data

2015-09-16T13:46:49+00:00

Irq affinity mask is per-irq instead of per irqchip, so move it into struct irq_common_data. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Tony Luck Cc: Bjorn Helgaas Cc: Benjamin Herrenschmidt Cc: Randy Dunlap Cc: Yinghai Lu Cc: Borislav Petkov Cc: Jason Cooper Cc: Kevin Cernekee Cc: Arnd Bergmann Link: http://lkml.kernel.org/r/1433303281-27688-1-git-send-email-jiang.liu@linux.intel.com Signed-off-by: Thomas Gleixner

x86/apic: Serialize LVTT and TSC_DEADLINE writes

2015-09-14T16:29:59+00:00

The APIC LVTT register is MMIO mapped but the TSC_DEADLINE register is an MSR. The write to the TSC_DEADLINE MSR is not serializing, so it's not guaranteed that the write to LVTT has reached the APIC before the TSC_DEADLINE MSR is written. In such a case the write to the MSR is ignored and as a consequence the local timer interrupt never fires. The SDM decribes this issue for xAPIC and x2APIC modes. The serialization methods recommended by the SDM differ. xAPIC: "1. Memory-mapped write to LVT Timer Register, setting bits 18:17 to 10b. 2. WRMSR to the IA32_TSC_DEADLINE MSR a value much larger than current time-stamp counter. 3. If RDMSR of the IA32_TSC_DEADLINE MSR returns zero, go to step 2. 4. WRMSR to the IA32_TSC_DEADLINE MSR the desired deadline." x2APIC: "To allow for efficient access to the APIC registers in x2APIC mode, the serializing semantics of WRMSR are relaxed when writing to the APIC registers. Thus, system software should not use 'WRMSR to APIC registers in x2APIC mode' as a serializing instruction. Read and write accesses to the APIC registers will occur in program order. A WRMSR to an APIC register may complete before all preceding stores are globally visible; software can prevent this by inserting a serializing instruction, an SFENCE, or an MFENCE before the WRMSR." The xAPIC method is to just wait for the memory mapped write to hit the LVTT by checking whether the MSR write has reached the hardware. There is no reason why a proper MFENCE after the memory mapped write would not do the same. Andi Kleen confirmed that MFENCE is sufficient for the xAPIC case as well. Issue MFENCE before writing to the TSC_DEADLINE MSR. This can be done unconditionally as all CPUs which have TSC_DEADLINE also have MFENCE support. [ tglx: Massaged the changelog ] Signed-off-by: Shaohua Li Reviewed-by: Ingo Molnar Cc: Cc: Cc: Cc: Andi Kleen Cc: H. Peter Anvin Cc: stable@vger.kernel.org #v3.7+ Link: http://lkml.kernel.org/r/20150909041352.GA2059853@devbig257.prn2.facebook.com Signed-off-by: Thomas Gleixner

x86/ioapic: Force affinity setting in setup_ioapic_dest()

2015-09-14T16:28:15+00:00

The recent ioapic cleanups changed the affinity setting in setup_ioapic_dest() from a direct write to the hardware to the delayed affinity setup via irq_set_affinity(). That results in a warning from chained_irq_exit(): WARNING: CPU: 0 PID: 5 at kernel/irq/migration.c:32 irq_move_masked_irq [] irq_move_masked_irq+0xb8/0xc0 [] ioapic_ack_level+0x111/0x130 [] intel_gpio_irq_handler+0x148/0x1c0 The reason is that irq_set_affinity() does not write directly to the hardware. It marks the affinity setting as pending and executes it from the next interrupt. The chained handler infrastructure does not take the irq descriptor lock for performance reasons because such a chained interrupt is not visible to any interfaces. So the delayed affinity setting triggers the warning in irq_move_masked_irq(). Restore the old behaviour by calling the set_affinity function of the ioapic chip in setup_ioapic_dest(). This is safe as none of the interrupts can be on the fly at this point. Fixes: aa5cb97f14a2 'x86/irq: Remove x86_io_apic_ops.set_affinity and related interfaces' Reported-and-tested-by: Mika Westerberg Signed-off-by: Thomas Gleixner Cc: Jiang Liu Cc: jarkko.nikula@linux.intel.com

Merge branch 'nmi' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2015-09-08T19:28:10+00:00

Pull NMI backtrace update from Russell King: "These changes convert the x86 NMI handling to be a library implementation which other architectures can make use of. Thomas Gleixner has reviewed and tested these changes, and wishes me to send these rather than taking them through the tip tree. The final patch in the set adds an initial implementation using this infrastructure to ARM, even though it doesn't send the IPI at "NMI" level. Patches are in progress to add the ARM equivalent of NMI, but we still need the IRQ-level fallback for systems where the "NMI" isn't available due to secure firmware denying access to it" * 'nmi' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: ARM: add basic support for on-demand backtrace of other CPUs nmi: x86: convert to generic nmi handler nmi: create generic NMI backtrace implementation

Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-01T22:20:51+00:00

Pull x86 apic updates from Thomas Gleixner: "This udpate contains: - rework the irq vector array to store a pointer to the irq descriptor instead of the irq number to avoid a lookup of the irq descriptor in the irq entry path - lguest interrupt handling cleanups - conversion of the local apic timer to the new clockevent callbacks - preparatory changes for the irq argument removal of interrupt flow handlers" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Do not dereference irq descriptor before checking it tools/lguest: Clean up include dir tools/lguest: Fix redefinition of struct virtio_pci_cfg_cap x86/irq: Store irq descriptor in vector array genirq: Provide irq_desc_has_action x86/irq: Get rid of an indentation level x86/irq: Rename VECTOR_UNDEFINED to VECTOR_UNUSED x86/irq: Replace numeric constant x86/irq: Protect smp_cleanup_move x86/lguest: Do not setup unused irq vectors x86/lguest: Clean up lguest_setup_irq x86/apic: Drop local_irq_save/restore in timer callbacks x86/apic: Migrate apic timer to new set_state interface x86/irq: Use access helper irq_data_get_affinity_mask() x86/irq: Use accessor irq_data_get_irq_handler_data() x86/irq: Use accessor irq_data_get_node()