kernel.git/arch/x86/kernel/idt.c, branch linux-4.20.y

x86: Don't include linux/irq.h from asm/hardirq.h

2018-08-05T07:53:13Z

The next patch in this series will have to make the definition of irq_cpustat_t available to entering_irq(). Inclusion of asm/hardirq.h into asm/apic.h would cause circular header dependencies like asm/smp.h asm/apic.h asm/hardirq.h linux/irq.h linux/topology.h linux/smp.h asm/smp.h or linux/gfp.h linux/mmzone.h asm/mmzone.h asm/mmzone_64.h asm/smp.h asm/apic.h asm/hardirq.h linux/irq.h linux/irqdesc.h linux/kobject.h linux/sysfs.h linux/kernfs.h linux/idr.h linux/gfp.h and others. This causes compilation errors because of the header guards becoming effective in the second inclusion: symbols/macros that had been defined before wouldn't be available to intermediate headers in the #include chain anymore. A possible workaround would be to move the definition of irq_cpustat_t into its own header and include that from both, asm/hardirq.h and asm/apic.h. However, this wouldn't solve the real problem, namely asm/harirq.h unnecessarily pulling in all the linux/irq.h cruft: nothing in asm/hardirq.h itself requires it. Also, note that there are some other archs, like e.g. arm64, which don't have that #include in their asm/hardirq.h. Remove the linux/irq.h #include from x86' asm/hardirq.h. Fix resulting compilation errors by adding appropriate #includes to *.c files as needed. Note that some of these *.c files could be cleaned up a bit wrt. to their set of #includes, but that should better be done from separate patches, if at all. Signed-off-by: Nicolai Stange Signed-off-by: Thomas Gleixner

x86/idt: Simplify the idt_setup_apic_and_irq_gates()

2018-06-06T11:38:01Z

The idt_setup_apic_and_irq_gates() sets the gates from FIRST_EXTERNAL_VECTOR up to FIRST_SYSTEM_VECTOR first. then secondly, from FIRST_SYSTEM_VECTOR to NR_VECTORS, it takes both APIC=y and APIC=n into account. But for APIC=n, the FIRST_SYSTEM_VECTOR is equal to NR_VECTORS, all vectors has been set at the first step. Simplify the second step, make it just work for APIC=y. Signed-off-by: Dou Liyang Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20180523023555.2933-1-douly.fnst@cn.fujitsu.com

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

2018-03-31T17:50:30Z

Pull x86 fixes from Ingo Molnar: "Two UV platform fixes, and a kbuild fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/platform/UV: Fix critical UV MMR address error x86/platform/uv/BAU: Add APIC idt entry x86/purgatory: Avoid creating stray ..d files, remove -MD from KBUILD_CFLAGS

x86/platform/uv/BAU: Add APIC idt entry

2018-03-28T08:40:55Z

BAU uses the old alloc_initr_gate90 method to setup its interrupt. This fails silently as the BAU vector is in the range of APIC vectors that are registered to the spurious interrupt handler. As a consequence BAU broadcasts are not handled, and the broadcast source CPU hangs. Update BAU to use new idt structure. Fixes: dc20b2d52653 ("x86/idt: Move interrupt gate initialization to IDT code") Signed-off-by: Andrew Banman Signed-off-by: Thomas Gleixner Acked-by: Mike Travis Cc: Dimitri Sivanich Cc: Russ Anderson Cc: stable@vger.kernel.org Cc: "H. Peter Anvin" Link: https://lkml.kernel.org/r/1522188546-196177-1-git-send-email-abanman@hpe.com

x86/entry/64: Don't use IST entry for #BP stack

2018-03-23T20:10:36Z

There's nothing IST-worthy about #BP/int3. We don't allow kprobes in the small handful of places in the kernel that run at CPL0 with an invalid stack, and 32-bit kernels have used normal interrupt gates for #BP forever. Furthermore, we don't allow kprobes in places that have usergs while in kernel mode, so "paranoid" is also unnecessary. Signed-off-by: Andy Lutomirski Signed-off-by: Linus Torvalds Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org

x86/idt: Mark IDT tables __initconst

2018-01-14T19:09:45Z

const variables must use __initconst, not __initdata. Fix this up for the IDT tables, which got it consistently wrong. Fixes: 16bc18d895ce ("x86/idt: Move 32-bit idt_descr to C code") Signed-off-by: Andi Kleen Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20171222001821.2157-7-andi@firstfloor.org

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

2017-11-14T02:29:23Z

Pull x86 APIC updates from Thomas Gleixner: "This update provides a major overhaul of the APIC initialization and vector allocation code: - Unification of the APIC and interrupt mode setup which was scattered all over the place and was hard to follow. This also distangles the timer setup from the APIC initialization which brings a clear separation of functionality. Great detective work from Dou Lyiang! - Refactoring of the x86 vector allocation mechanism. The existing code was based on nested loops and rather convoluted APIC callbacks which had a horrible worst case behaviour and tried to serve all different use cases in one go. This led to quite odd hacks when supporting the new managed interupt facility for multiqueue devices and made it more or less impossible to deal with the vector space exhaustion which was a major roadblock for server hibernation. Aside of that the code dealing with cpu hotplug and the system vectors was disconnected from the actual vector management and allocation code, which made it hard to follow and maintain. Utilizing the new bitmap matrix allocator core mechanism, the new allocator and management code consolidates the handling of system vectors, legacy vectors, cpu hotplug mechanisms and the actual allocation which needs to be aware of system and legacy vectors and hotplug constraints into a single consistent entity. This has one visible change: The support for multi CPU targets of interrupts, which is only available on a certain subset of CPUs/APIC variants has been removed in favour of single interrupt targets. A proper analysis of the multi CPU target feature revealed that there is no real advantage as the vast majority of interrupts end up on the CPU with the lowest APIC id in the set of target CPUs anyway. That change was agreed on by the relevant folks and allowed to simplify the implementation significantly and to replace rather fragile constructs like the vector cleanup IPI with straight forward and solid code. Furthermore this allowed to cleanly separate the allocation details for legacy, normal and managed interrupts: * Legacy interrupts are not longer wasting 16 vectors unconditionally * Managed interrupts have now a guaranteed vector reservation, but the actual vector assignment happens when the interrupt is requested. It's guaranteed not to fail. * Normal interrupts no longer allocate vectors unconditionally when the interrupt is set up (IO/APIC init or MSI(X) enable). The mechanism has been switched to a best effort reservation mode. The actual allocation happens when the interrupt is requested. Contrary to managed interrupts the request can fail due to vector space exhaustion, but drivers must handle a fail of request_irq() anyway. When the interrupt is freed, the vector is handed back as well. This solves a long standing problem with large unconditional vector allocations for a certain class of enterprise devices which prevented server hibernation due to vector space exhaustion when the unused allocated vectors had to be migrated to CPU0 while unplugging all non boot CPUs. The code has been equipped with trace points and detailed debugfs information to aid analysis of the vector space" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits) x86/vector/msi: Select CONFIG_GENERIC_IRQ_RESERVATION_MODE PCI/MSI: Set MSI_FLAG_MUST_REACTIVATE in core code genirq: Add config option for reservation mode x86/vector: Use correct per cpu variable in free_moved_vector() x86/apic/vector: Ignore set_affinity call for inactive interrupts x86/apic: Fix spelling mistake: "symmectic" -> "symmetric" x86/apic: Use dead_cpu instead of current CPU when cleaning up ACPI/init: Invoke early ACPI initialization earlier x86/vector: Respect affinity mask in irq descriptor x86/irq: Simplify hotplug vector accounting x86/vector: Switch IOAPIC to global reservation mode x86/vector/msi: Switch to global reservation mode x86/vector: Handle managed interrupts proper x86/io_apic: Reevaluate vector configuration on activate() iommu/amd: Reevaluate vector configuration on activate() iommu/vt-d: Reevaluate vector configuration on activate() x86/apic/msi: Force reactivation of interrupts at startup time x86/vector: Untangle internal state from irq_cfg x86/vector: Compile SMP only code conditionally x86/apic: Remove unused callbacks ...

x86/idt: Remove X86_TRAP_BP initialization in idt_setup_traps()

2017-11-08T20:05:23Z

Commit b70543a0b2b6("x86/idt: Move regular trap init to tables") moves regular trap init for each trap vector into a table based initialization. It introduced the initialization for vector X86_TRAP_BP which was not in the code which it replaced. This breaks uprobe functionality for x86_32; the probed program segfaults instead of handling the probe proper. The reason for this is that TRAP_BP is set up as system interrupt gate (DPL3) in the early IDT and then replaced by a regular interrupt gate (DPL0) in idt_setup_traps(). The DPL0 restriction causes the int3 trap to fail with a #GP resulting in a SIGSEGV of the probed program. On 64bit this does not cause a problem because the IDT entry is replaced with a system interrupt gate (DPL3) with interrupt stack afterwards. Remove X86_TRAP_BP from the def_idts table which is used in idt_setup_traps(). Remove a redundant entry for X86_TRAP_NMI in def_idts while at it. Tested on both x86_64 and x86_32. [ tglx: Amended changelog with a description of the root cause ] Fixes: b70543a0b2b6("x86/idt: Move regular trap init to tables") Reported-and-tested-by: Yonghong Song Signed-off-by: Yonghong Song Signed-off-by: Thomas Gleixner Cc: a.p.zijlstra@chello.nl Cc: ast@fb.com Cc: oleg@redhat.com Cc: luto@kernel.org Cc: kernel-team@fb.com Link: https://lkml.kernel.org/r/20171108192845.552709-1-yhs@fb.com

x86/vector: Rename used_vectors to system_vectors

2017-09-25T18:51:52Z

used_vectors is a nisnomer as it only has the system vectors which are excluded from the regular vector allocation marked. It's not what the name suggests storage for the actually used vectors. Signed-off-by: Thomas Gleixner Tested-by: Juergen Gross Tested-by: Yu Chen Acked-by: Juergen Gross Cc: Boris Ostrovsky Cc: Tony Luck Cc: Marc Zyngier Cc: Alok Kataria Cc: Joerg Roedel Cc: "Rafael J. Wysocki" Cc: Steven Rostedt Cc: Christoph Hellwig Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Paolo Bonzini Cc: Rui Zhang Cc: "K. Y. Srinivasan" Cc: Arjan van de Ven Cc: Dan Williams Cc: Len Brown Link: https://lkml.kernel.org/r/20170913213154.150209009@linutronix.de

x86/idt: Fix the X86_TRAP_BP gate

2017-09-01T09:04:56Z

Andrei Vagin reported a CRIU regression and bisected it back to: 90f6225fba0c ("x86/idt: Move IST stack based traps to table init") This table init conversion loses the system-gate property of X86_TRAP_BP and erroneously moves it from DPL3 to DPL0. Fix it. Reported-by: Andrei Vagin Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Cc: dvlasenk@redhat.com Cc: linux-tip-commits@vger.kernel.org Cc: peterz@infradead.org Cc: brgerst@gmail.com Cc: rostedt@goodmis.org Cc: bp@alien8.de Cc: luto@kernel.org Cc: jpoimboe@redhat.com Cc: Cyrill Gorcunov Cc: torvalds@linux-foundation.org Cc: tip-bot for Jacob Shin Link: http://lkml.kernel.org/r/20170901082630.xvyi5bwk6etmppqc@gmail.com