user/sven/linux.git/kernel/irq, branch v4.14.259

genirq: Disable interrupts for force threaded handlers

2021-03-24T10:05:06Z

commit 81e2073c175b887398e5bca6c004efa89983f58d upstream. With interrupt force threading all device interrupt handlers are invoked from kernel threads. Contrary to hard interrupt context the invocation only disables bottom halfs, but not interrupts. This was an oversight back then because any code like this will have an issue: thread(irq_A) irq_handler(A) spin_lock(&foo->lock); interrupt(irq_B) irq_handler(B) spin_lock(&foo->lock); This has been triggered with networking (NAPI vs. hrtimers) and console drivers where printk() happens from an interrupt which interrupted the force threaded handler. Now people noticed and started to change the spin_lock() in the handler to spin_lock_irqsave() which affects performance or add IRQF_NOTHREAD to the interrupt request which in turn breaks RT. Fix the root cause and not the symptom and disable interrupts before invoking the force threaded handler which preserves the regular semantics and the usefulness of the interrupt force threading as a general debugging tool. For not RT this is not changing much, except that during the execution of the threaded handler interrupts are delayed until the handler returns. Vs. scheduling and softirq processing there is no difference. For RT kernels there is no issue. Fixes: 8d32a307e4fa ("genirq: Provide forced interrupt threading") Reported-by: Johan Hovold Signed-off-by: Thomas Gleixner Reviewed-by: Johan Hovold Acked-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20210317143859.513307808@linutronix.de Signed-off-by: Greg Kroah-Hartman

genirq/irqdomain: Don't try to free an interrupt that has no mapping

2020-12-29T12:46:56Z

[ Upstream commit 4615fbc3788ddc8e7c6d697714ad35a53729aa2c ] When an interrupt allocation fails for N interrupts, it is pretty common for the error handling code to free the same number of interrupts, no matter how many interrupts have actually been allocated. This may result in the domain freeing code to be unexpectedly called for interrupts that have no mapping in that domain. Things end pretty badly. Instead, add some checks to irq_domain_free_irqs_hierarchy() to make sure that thiss does not follow the hierarchy if no mapping exists for a given interrupt. Fixes: 6a6544e520abe ("genirq/irqdomain: Remove auto-recursive hierarchy support") Signed-off-by: Marc Zyngier Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20201129135551.396777-1-maz@kernel.org Signed-off-by: Sasha Levin

genirq: Let GENERIC_IRQ_IPI select IRQ_DOMAIN_HIERARCHY

2020-11-18T17:27:53Z

[ Upstream commit 151a535171be6ff824a0a3875553ea38570f4c05 ] kernel/irq/ipi.c otherwise fails to compile if nothing else selects it. Fixes: 379b656446a3 ("genirq: Add GENERIC_IRQ_IPI Kconfig symbol") Reported-by: Pavel Machek Tested-by: Pavel Machek Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20201015101222.GA32747@amd Signed-off-by: Sasha Levin

genirq/affinity: Make affinity setting if activated opt-in

2020-08-21T07:48:23Z

commit f0c7baca180046824e07fc5f1326e83a8fd150c7 upstream. 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 Signed-off-by: Thomas Gleixner Tested-by: Marc Zyngier Acked-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/87blk4tzgm.fsf@nanos.tec.linutronix.de [fllinden@amazon.com - backported to 4.14] Signed-off-by: Frank van der Linden Signed-off-by: Greg Kroah-Hartman

genirq/affinity: Handle affinity setting on inactive interrupts correctly

2020-08-21T07:48:23Z

commit baedb87d1b53532f81b4bd0387f83b05d4f7eb9a upstream. 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 Signed-off-by: Thomas Gleixner Tested-by: Ali Saidi Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200529015501.15771-1-alisaidi@amazon.com Link: https://lkml.kernel.org/r/877dv2rv25.fsf@nanos.tec.linutronix.de [fllinden@amazon.com - 4.14 never had the x86 workaround, so skip x86 changes] Signed-off-by: Frank van der Linden Signed-off-by: Greg Kroah-Hartman

genirq/generic_pending: Do not lose pending affinity update

2020-06-03T06:18:12Z

[ Upstream commit a33a5d2d16cb84bea8d5f5510f3a41aa48b5c467 ] The generic pending interrupt mechanism moves interrupts from the interrupt handler on the original target CPU to the new destination CPU. This is required for x86 and ia64 due to the way the interrupt delivery and acknowledge works if the interrupts are not remapped. However that update can fail for various reasons. Some of them are valid reasons to discard the pending update, but the case, when the previous move has not been fully cleaned up is not a legit reason to fail. Check the return value of irq_do_set_affinity() for -EBUSY, which indicates a pending cleanup, and rearm the pending move in the irq dexcriptor so it's tried again when the next interrupt arrives. Fixes: 996c591227d9 ("x86/irq: Plug vector cleanup race") Signed-off-by: Thomas Gleixner Tested-by: Song Liu Cc: Joerg Roedel Cc: Peter Zijlstra Cc: Song Liu Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: stable@vger.kernel.org Cc: Mike Travis Cc: Borislav Petkov Cc: Tariq Toukan Link: https://lkml.kernel.org/r/20180604162224.386544292@linutronix.de Signed-off-by: Sasha Levin

genirq/irqdomain: Check pointer in irq_domain_alloc_irqs_hierarchy()

2020-04-24T06:00:28Z

[ Upstream commit 87f2d1c662fa1761359fdf558246f97e484d177a ] irq_domain_alloc_irqs_hierarchy() has 3 call sites in the compilation unit but only one of them checks for the pointer which is being dereferenced inside the called function. Move the check into the function. This allows for catching the error instead of the following crash: Unable to handle kernel NULL pointer dereference at virtual address 00000000 PC is at 0x0 LR is at gpiochip_hierarchy_irq_domain_alloc+0x11f/0x140 ... [] (gpiochip_hierarchy_irq_domain_alloc) [] (__irq_domain_alloc_irqs) [] (irq_create_fwspec_mapping) [] (gpiochip_to_irq) [] (gpiod_to_irq) [] (gpio_irqs_init [gpio_irqs]) [] (gpio_irqs_exit+0xecc/0xe84 [gpio_irqs]) Code: bad PC value Signed-off-by: Alexander Sverdlin Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20200306174720.82604-1-alexander.sverdlin@nokia.com Signed-off-by: Sasha Levin

genirq: Fix reference leaks on irq affinity notifiers

2020-04-02T14:34:31Z

commit df81dfcfd6991d547653d46c051bac195cd182c1 upstream. The handling of notify->work did not properly maintain notify->kref in two cases: 1) where the work was already scheduled, another irq_set_affinity_locked() would get the ref and (no-op-ly) schedule the work. Thus when irq_affinity_notify() ran, it would drop the original ref but not the additional one. 2) when cancelling the (old) work in irq_set_affinity_notifier(), if there was outstanding work a ref had been got for it but was never put. Fix both by checking the return values of the work handling functions (schedule_work() for (1) and cancel_work_sync() for (2)) and put the extra ref if the return value indicates preexisting work. Fixes: cd7eab44e994 ("genirq: Add IRQ affinity notifiers") Fixes: 59c39840f5ab ("genirq: Prevent use-after-free and work list corruption") Signed-off-by: Edward Cree Signed-off-by: Thomas Gleixner Acked-by: Ben Hutchings Link: https://lkml.kernel.org/r/24f5983f-2ab5-e83a-44ee-a45b5f9300f5@solarflare.com Signed-off-by: Greg Kroah-Hartman

genirq/proc: Reject invalid affinity masks (again)

2020-02-28T15:36:15Z

commit cba6437a1854fde5934098ec3bd0ee83af3129f5 upstream. Qian Cai reported that the WARN_ON() in the x86/msi affinity setting code, which catches cases where the affinity setting is not done on the CPU which is the current target of the interrupt, triggers during CPU hotplug stress testing. It turns out that the warning which was added with the commit addressing the MSI affinity race unearthed yet another long standing bug. If user space writes a bogus affinity mask, i.e. it contains no online CPUs, then it calls irq_select_affinity_usr(). This was introduced for ALPHA in eee45269b0f5 ("[PATCH] Alpha: convert to generic irq framework (generic part)") and subsequently made available for all architectures in 18404756765c ("genirq: Expose default irq affinity mask (take 3)") which introduced the circumvention of the affinity setting restrictions for interrupt which cannot be moved in process context. The whole exercise is bogus in various aspects: 1) If the interrupt is already started up then there is absolutely no point to honour a bogus interrupt affinity setting from user space. The interrupt is already assigned to an online CPU and it does not make any sense to reassign it to some other randomly chosen online CPU. 2) If the interupt is not yet started up then there is no point either. A subsequent startup of the interrupt will invoke irq_setup_affinity() anyway which will chose a valid target CPU. So the only correct solution is to just return -EINVAL in case user space wrote an affinity mask which does not contain any online CPUs, except for ALPHA which has it's own magic sauce for this. Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)") Reported-by: Qian Cai Signed-off-by: Thomas Gleixner Tested-by: Qian Cai Link: https://lkml.kernel.org/r/878sl8xdbm.fsf@nanos.tec.linutronix.de Signed-off-by: Greg Kroah-Hartman

irqdomain: Fix a memory leak in irq_domain_push_irq()

2020-02-14T21:32:08Z

commit 0f394daef89b38d58c91118a2b08b8a1b316703b upstream. Fix a memory leak reported by kmemleak: unreferenced object 0xffff000bc6f50e80 (size 128): comm "kworker/23:2", pid 201, jiffies 4294894947 (age 942.132s) hex dump (first 32 bytes): 00 00 00 00 41 00 00 00 86 c0 03 00 00 00 00 00 ....A........... 00 a0 b2 c6 0b 00 ff ff 40 51 fd 10 00 80 ff ff ........@Q...... backtrace: [<00000000e62d2240>] kmem_cache_alloc_trace+0x1a4/0x320 [<00000000279143c9>] irq_domain_push_irq+0x7c/0x188 [<00000000d9f4c154>] thunderx_gpio_probe+0x3ac/0x438 [<00000000fd09ec22>] pci_device_probe+0xe4/0x198 [<00000000d43eca75>] really_probe+0xdc/0x320 [<00000000d3ebab09>] driver_probe_device+0x5c/0xf0 [<000000005b3ecaa0>] __device_attach_driver+0x88/0xc0 [<000000004e5915f5>] bus_for_each_drv+0x7c/0xc8 [<0000000079d4db41>] __device_attach+0xe4/0x140 [<00000000883bbda9>] device_initial_probe+0x18/0x20 [<000000003be59ef6>] bus_probe_device+0x98/0xa0 [<0000000039b03d3f>] deferred_probe_work_func+0x74/0xa8 [<00000000870934ce>] process_one_work+0x1c8/0x470 [<00000000e3cce570>] worker_thread+0x1f8/0x428 [<000000005d64975e>] kthread+0xfc/0x128 [<00000000f0eaa764>] ret_from_fork+0x10/0x18 Fixes: 495c38d3001f ("irqdomain: Add irq_domain_{push,pop}_irq() functions") Signed-off-by: Kevin Hao Signed-off-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200120043547.22271-1-haokexin@gmail.com Signed-off-by: Greg Kroah-Hartman