user/sven/linux.git/kernel/irq, branch v6.1.97

genirq/cpuhotplug, x86/vector: Prevent vector leak during CPU offline

2024-06-12T09:03:01Z

commit a6c11c0a5235fb144a65e0cb2ffd360ddc1f6c32 upstream. The absence of IRQD_MOVE_PCNTXT prevents immediate effectiveness of interrupt affinity reconfiguration via procfs. Instead, the change is deferred until the next instance of the interrupt being triggered on the original CPU. When the interrupt next triggers on the original CPU, the new affinity is enforced within __irq_move_irq(). A vector is allocated from the new CPU, but the old vector on the original CPU remains and is not immediately reclaimed. Instead, apicd->move_in_progress is flagged, and the reclaiming process is delayed until the next trigger of the interrupt on the new CPU. Upon the subsequent triggering of the interrupt on the new CPU, irq_complete_move() adds a task to the old CPU's vector_cleanup list if it remains online. Subsequently, the timer on the old CPU iterates over its vector_cleanup list, reclaiming old vectors. However, a rare scenario arises if the old CPU is outgoing before the interrupt triggers again on the new CPU. In that case irq_force_complete_move() is not invoked on the outgoing CPU to reclaim the old apicd->prev_vector because the interrupt isn't currently affine to the outgoing CPU, and irq_needs_fixup() returns false. Even though __vector_schedule_cleanup() is later called on the new CPU, it doesn't reclaim apicd->prev_vector; instead, it simply resets both apicd->move_in_progress and apicd->prev_vector to 0. As a result, the vector remains unreclaimed in vector_matrix, leading to a CPU vector leak. To address this issue, move the invocation of irq_force_complete_move() before the irq_needs_fixup() call to reclaim apicd->prev_vector, if the interrupt is currently or used to be affine to the outgoing CPU. Additionally, reclaim the vector in __vector_schedule_cleanup() as well, following a warning message, although theoretically it should never see apicd->move_in_progress with apicd->prev_cpu pointing to an offline CPU. Fixes: f0383c24b485 ("genirq/cpuhotplug: Add support for cleaning up move in progress") Signed-off-by: Dongli Zhang Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20240522220218.162423-1-dongli.zhang@oracle.com Signed-off-by: Greg Kroah-Hartman

genirq/affinity: Move group_cpus_evenly() into lib/

2024-01-10T16:10:33Z

[ Upstream commit f7b3ea8cf72f3d6060fe08e461805181e7450a13 ] group_cpus_evenly() has become a generic function which can be used for other subsystems than the interrupt subsystem, so move it into lib/. Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Reviewed-by: Christoph Hellwig Reviewed-by: Jens Axboe Link: https://lore.kernel.org/r/20221227022905.352674-6-ming.lei@redhat.com Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly") Signed-off-by: Sasha Levin

genirq/affinity: Rename irq_build_affinity_masks as group_cpus_evenly

2024-01-10T16:10:33Z

[ Upstream commit 523f1ea76aad9025f9bd5258d77f4406fa9dbe5d ] Map irq vector into group, which allows to abstract the algorithm for a generic use case outside of the interrupt core. Rename irq_build_affinity_masks as group_cpus_evenly, so the API can be reused for blk-mq to make default queue mapping even though irq vectors aren't involved. No functional change, just rename vector as group. Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Reviewed-by: Christoph Hellwig Reviewed-by: Jens Axboe Link: https://lore.kernel.org/r/20221227022905.352674-5-ming.lei@redhat.com Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly") Signed-off-by: Sasha Levin

genirq/affinity: Don't pass irq_affinity_desc array to irq_build_affinity_masks

2024-01-10T16:10:33Z

[ Upstream commit e7bdd7f0cbd1c001bb9b4d3313edc5ee094bc3f8 ] Prepare for abstracting irq_build_affinity_masks() into a public function for assigning all CPUs evenly into several groups. Don't pass irq_affinity_desc array to irq_build_affinity_masks, instead return a cpumask array by storing each assigned group into one element of the array. This allows to provide a generic interface for grouping all CPUs evenly from a NUMA and CPU locality viewpoint, and the cost is one extra allocation in irq_build_affinity_masks(), which should be fine since it is done via GFP_KERNEL and irq_build_affinity_masks() is a slow path anyway. Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Reviewed-by: Christoph Hellwig Reviewed-by: John Garry Reviewed-by: Jens Axboe Link: https://lore.kernel.org/r/20221227022905.352674-4-ming.lei@redhat.com Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly") Signed-off-by: Sasha Levin

genirq/affinity: Pass affinity managed mask array to irq_build_affinity_masks

2024-01-10T16:10:33Z

[ Upstream commit 1f962d91a15af54301c63febb8ac2ba07aa3654f ] Pass affinity managed mask array to irq_build_affinity_masks() so that the index of the first affinity managed vector is always zero. This allows to simplify the implementation a bit. Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Reviewed-by: Christoph Hellwig Reviewed-by: John Garry Reviewed-by: Jens Axboe Link: https://lore.kernel.org/r/20221227022905.352674-3-ming.lei@redhat.com Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly") Signed-off-by: Sasha Levin

genirq/affinity: Remove the 'firstvec' parameter from irq_build_affinity_masks

2024-01-10T16:10:33Z

[ Upstream commit cdf07f0ea48a3b52f924714d477366ac510ee870 ] The 'firstvec' parameter is always same with the parameter of 'startvec', so use 'startvec' directly inside irq_build_affinity_masks(). Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Reviewed-by: Christoph Hellwig Reviewed-by: John Garry Reviewed-by: Jens Axboe Link: https://lore.kernel.org/r/20221227022905.352674-2-ming.lei@redhat.com Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly") Signed-off-by: Sasha Levin

x86/apic/msi: Fix misconfigured non-maskable MSI quirk

2023-12-08T07:51:20Z

commit b56ebe7c896dc78b5865ec2c4b1dae3c93537517 upstream. commit ef8dd01538ea ("genirq/msi: Make interrupt allocation less convoluted"), reworked the code so that the x86 specific quirk for affinity setting of non-maskable PCI/MSI interrupts is not longer activated if necessary. This could be solved by restoring the original logic in the core MSI code, but after a deeper analysis it turned out that the quirk flag is not required at all. The quirk is only required when the PCI/MSI device cannot mask the MSI interrupts, which in turn also prevents reservation mode from being enabled for the affected interrupt. This allows ot remove the NOMASK quirk bit completely as msi_set_affinity() can instead check whether reservation mode is enabled for the interrupt, which gives exactly the same answer. Even in the momentary non-existing case that the reservation mode would be not set for a maskable MSI interrupt this would not cause any harm as it just would cause msi_set_affinity() to go needlessly through the functionaly equivalent slow path, which works perfectly fine with maskable interrupts as well. Rework msi_set_affinity() to query the reservation mode and remove all NOMASK quirk logic from the core code. [ tglx: Massaged changelog ] Fixes: ef8dd01538ea ("genirq/msi: Make interrupt allocation less convoluted") Suggested-by: Thomas Gleixner Signed-off-by: Koichiro Den Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20231026032036.2462428-1-den@valinux.co.jp Signed-off-by: Greg Kroah-Hartman

genirq/generic_chip: Make irq_remove_generic_chip() irqdomain aware

2023-11-28T17:07:10Z

commit 5e7afb2eb7b2a7c81e9f608cbdf74a07606fd1b5 upstream. irq_remove_generic_chip() calculates the Linux interrupt number for removing the handler and interrupt chip based on gc::irq_base as a linear function of the bit positions of set bits in the @msk argument. When the generic chip is present in an irq domain, i.e. created with a call to irq_alloc_domain_generic_chips(), gc::irq_base contains not the base Linux interrupt number. It contains the base hardware interrupt for this chip. It is set to 0 for the first chip in the domain, 0 + N for the next chip, where $N is the number of hardware interrupts per chip. That means the Linux interrupt number cannot be calculated based on gc::irq_base for irqdomain based chips without a domain map lookup, which is currently missing. Rework the code to take the irqdomain case into account and calculate the Linux interrupt number by a irqdomain lookup of the domain specific hardware interrupt number. [ tglx: Massage changelog. Reshuffle the logic and add a proper comment. ] Fixes: cfefd21e693d ("genirq: Add chip suspend and resume callbacks") Signed-off-by: Herve Codina Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20231024150335.322282-1-herve.codina@bootlin.com Signed-off-by: Greg Kroah-Hartman

genirq/matrix: Exclude managed interrupts in irq_matrix_allocated()

2023-11-20T10:51:51Z

[ Upstream commit a0b0bad10587ae2948a7c36ca4ffc206007fbcf3 ] When a CPU is about to be offlined, x86 validates that all active interrupts which are targeted to this CPU can be migrated to the remaining online CPUs. If not, the offline operation is aborted. The validation uses irq_matrix_allocated() to retrieve the number of vectors which are allocated on the outgoing CPU. The returned number of allocated vectors includes also vectors which are associated to managed interrupts. That's overaccounting because managed interrupts are: - not migrated when the affinity mask of the interrupt targets only the outgoing CPU - migrated to another CPU, but in that case the vector is already pre-allocated on the potential target CPUs and must not be taken into account. As a consequence the check whether the remaining online CPUs have enough capacity for migrating the allocated vectors from the outgoing CPU might fail incorrectly. Let irq_matrix_allocated() return only the number of allocated non-managed interrupts to make this validation check correct. [ tglx: Amend changelog and fixup kernel-doc comment ] Fixes: 2f75d9e1c905 ("genirq: Implement bitmap matrix allocator") Reported-by: Wendy Wang Signed-off-by: Chen Yu Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20231020072522.557846-1-yu.c.chen@intel.com Signed-off-by: Sasha Levin

x86/pci/xen: populate MSI sysfs entries

2023-05-30T13:03:22Z

commit 335b4223466dd75f9f3ea4918187afbadd22e5c8 upstream. Commit bf5e758f02fc ("genirq/msi: Simplify sysfs handling") reworked the creation of sysfs entries for MSI IRQs. The creation used to be in msi_domain_alloc_irqs_descs_locked after calling ops->domain_alloc_irqs. Then it moved into __msi_domain_alloc_irqs which is an implementation of domain_alloc_irqs. However, Xen comes with the only other implementation of domain_alloc_irqs and hence doesn't run the sysfs population code anymore. Commit 6c796996ee70 ("x86/pci/xen: Fixup fallout from the PCI/MSI overhaul") set the flag MSI_FLAG_DEV_SYSFS for the xen msi_domain_info but that doesn't actually have an effect because Xen uses it's own domain_alloc_irqs implementation. Fix this by making use of the fallback functions for sysfs population. Fixes: bf5e758f02fc ("genirq/msi: Simplify sysfs handling") Signed-off-by: Maximilian Heyne Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/20230503131656.15928-1-mheyne@amazon.de Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman