kernel/linux.git/drivers/xen/events, branch linux-4.16.y

xen/pirq: fix error path cleanup when binding MSIs

2018-02-28T19:20:01+00:00

Current cleanup in the error path of xen_bind_pirq_msi_to_irq is wrong. First of all there's an off-by-one in the cleanup loop, which can lead to unbinding wrong IRQs. Secondly IRQs not bound won't be freed, thus leaking IRQ numbers. Note that there's no need to differentiate between bound and unbound IRQs when freeing them, __unbind_from_irq will deal with both of them correctly. Fixes: 4892c9b4ada9f9 ("xen: add support for MSI message groups") Reported-by: Hooman Mirhadi Signed-off-by: Roger Pau Monné Reviewed-by: Amit Shah Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

Merge tag 'for-linus-4.14b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2017-09-07T17:24:21+00:00

Pull xen updates from Juergen Gross: - the new pvcalls backend for routing socket calls from a guest to dom0 - some cleanups of Xen code - a fix for wrong usage of {get,put}_cpu() * tag 'for-linus-4.14b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (27 commits) xen/mmu: set MMU_NORMAL_PT_UPDATE in remap_area_mfn_pte_fn xen: Don't try to call xen_alloc_p2m_entry() on autotranslating guests xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init() xen/pvcalls: use WARN_ON(1) instead of __WARN() xen: remove not used trace functions xen: remove unused function xen_set_domain_pte() xen: remove tests for pvh mode in pure pv paths xen-platform: constify pci_device_id. xen: cleanup xen.h xen: introduce a Kconfig option to enable the pvcalls backend xen/pvcalls: implement write xen/pvcalls: implement read xen/pvcalls: implement the ioworker functions xen/pvcalls: disconnect and module_exit xen/pvcalls: implement release command xen/pvcalls: implement poll command xen/pvcalls: implement accept command xen/pvcalls: implement listen command xen/pvcalls: implement bind command xen/pvcalls: implement connect command ...

xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init()

2017-08-31T13:45:55+00:00

When booting Linux as Xen guest with CONFIG_DEBUG_ATOMIC, the following splat appears: [ 0.002323] Mountpoint-cache hash table entries: 1024 (order: 1, 8192 bytes) [ 0.019717] ASID allocator initialised with 65536 entries [ 0.020019] xen:grant_table: Grant tables using version 1 layout [ 0.020051] Grant table initialized [ 0.020069] BUG: sleeping function called from invalid context at /data/src/linux/mm/page_alloc.c:4046 [ 0.020100] in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0 [ 0.020123] no locks held by swapper/0/1. [ 0.020143] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc5 #598 [ 0.020166] Hardware name: FVP Base (DT) [ 0.020182] Call trace: [ 0.020199] [] dump_backtrace+0x0/0x270 [ 0.020222] [] show_stack+0x24/0x30 [ 0.020244] [] dump_stack+0xb8/0xf0 [ 0.020267] [] ___might_sleep+0x1c8/0x1f8 [ 0.020291] [] __might_sleep+0x58/0x90 [ 0.020313] [] __alloc_pages_nodemask+0x1c0/0x12e8 [ 0.020338] [] alloc_page_interleave+0x38/0x88 [ 0.020363] [] alloc_pages_current+0xdc/0xf0 [ 0.020387] [] __get_free_pages+0x28/0x50 [ 0.020411] [] evtchn_fifo_alloc_control_block+0x2c/0xa0 [ 0.020437] [] xen_evtchn_fifo_init+0x38/0xb4 [ 0.020461] [] xen_init_IRQ+0x44/0xc8 [ 0.020484] [] xen_guest_init+0x250/0x300 [ 0.020507] [] do_one_initcall+0x44/0x130 [ 0.020531] [] kernel_init_freeable+0x120/0x288 [ 0.020556] [] kernel_init+0x18/0x110 [ 0.020578] [] ret_from_fork+0x10/0x40 [ 0.020606] xen:events: Using FIFO-based ABI [ 0.020658] Xen: initializing cpu0 [ 0.027727] Hierarchical SRCU implementation. [ 0.036235] EFI services will not be available. [ 0.043810] smp: Bringing up secondary CPUs ... This is because get_cpu() in xen_evtchn_fifo_init() will disable preemption, but __get_free_page() might sleep (GFP_ATOMIC is not set). xen_evtchn_fifo_init() will always be called before SMP is initialized, so {get,put}_cpu() could be replaced by a simple smp_processor_id(). This also avoid to modify evtchn_fifo_alloc_control_block that will be called in other context. Signed-off-by: Julien Grall Reported-by: Andre Przywara Reviewed-by: Boris Ostrovsky Fixes: 1fe565517b57 ("xen/events: use the FIFO-based ABI if available") Signed-off-by: Boris Ostrovsky

x86/idt: Simplify alloc_intr_gate()

2017-08-29T10:07:28+00:00

The only users of alloc_intr_gate() are hypervisors, which both check the used_vectors bitmap whether they have allocated the gate already. Move that check into alloc_intr_gate() and simplify the users. Signed-off-by: Thomas Gleixner Reviewed-by: Juergen Gross Reviewed-by: K. Y. Srinivasan Cc: Andy Lutomirski Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephen Hemminger Cc: Steven Rostedt Link: http://lkml.kernel.org/r/20170828064959.580830286@linutronix.de Signed-off-by: Ingo Molnar

xen/events: Fix interrupt lost during irq_disable and irq_enable

2017-08-11T14:46:01+00:00

Here is a device has xen-pirq-MSI interrupt. Dom0 might lost interrupt during driver irq_disable/irq_enable. Here is the scenario, 1. irq_disable -> disable_dynirq -> mask_evtchn(irq channel) 2. dev interrupt raised by HW and Xen mark its evtchn as pending 3. irq_enable -> startup_pirq -> eoi_pirq -> clear_evtchn(channel of irq) -> clear pending status 4. consume_one_event process the irq event without pending bit assert which result in interrupt lost once 5. No HW interrupt raising anymore. Now use enable_dynirq for enable_pirq of xen_pirq_chip to remove eoi_pirq when irq_enable. Signed-off-by: Liu Shuo Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross

xen: dont fiddle with event channel masking in suspend/resume

2017-07-27T17:55:46+00:00

Instead of fiddling with masking the event channels during suspend and resume handling let do the irq subsystem do its job. It will do the mask and unmask operations as needed. Signed-off-by: Juergen Gross Acked-by: Thomas Gleixner Reviewed-by: Boris Ostrovsky Tested-by: Boris Ostrovsky Signed-off-by: Juergen Gross

Merge tag 'for-linus-4.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2017-07-07T02:11:24+00:00

Pull xen updates from Juergen Gross: "Other than fixes and cleanups it contains: - support > 32 VCPUs at domain restore - support for new sysfs nodes related to Xen - some performance tuning for Linux running as Xen guest" * tag 'for-linus-4.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: x86/xen: allow userspace access during hypercalls x86: xen: remove unnecessary variable in xen_foreach_remap_area() xen: allocate page for shared info page from low memory xen: avoid deadlock in xenbus driver xen: add sysfs node for hypervisor build id xen: sync include/xen/interface/version.h xen: add sysfs node for guest type doc,xen: document hypervisor sysfs nodes for xen xen/vcpu: Handle xen_vcpu_setup() failure at boot xen/vcpu: Handle xen_vcpu_setup() failure in hotplug xen/pv: Fix OOPS on restore for a PV, !SMP domain xen/pvh*: Support > 32 VCPUs at domain restore xen/vcpu: Simplify xen_vcpu related code xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPU xen: avoid type warning in xchg_xen_ulong xen: fix HYPERVISOR_dm_op() prototype xen: don't print error message in case of missing Xenstore entry arm/xen: Adjust one function call together with a variable assignment arm/xen: Delete an error message for a failed memory allocation in __set_phys_to_machine_multi() arm/xen: Improve a size determination in __set_phys_to_machine_multi()

xen/events: Add support for effective affinity mask

2017-06-22T16:21:23+00:00

Update the effective affinity mask when an interrupt was successfully targeted to a CPU. Signed-off-by: Thomas Gleixner Cc: Jens Axboe Cc: Marc Zyngier Cc: Michael Ellerman Cc: Keith Busch Cc: Peter Zijlstra Cc: Christoph Hellwig Link: http://lkml.kernel.org/r/20170619235446.799944725@linutronix.de

xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPU

2017-06-13T13:30:27+00:00

A HVM domian booting generates around 200K (evtchn:qemu-dm xen-dyn) interrupts,in a short period of time. All these evtchn:qemu-dm are bound to VCPU 0, until irqbalance sees these IRQ and moves it to a different VCPU. In one configuration, irqbalance runs every 10 seconds, which means irqbalance doesn't get to see these burst of interrupts and doesn't re-balance interrupts most of the time, making all evtchn:qemu-dm to be processed by VCPU0. This cause VCPU0 to spend most of time processing hardirq and very little time on softirq. Moreover, if dom0 kernel PREEMPTION is disabled, VCPU0 never runs watchdog (process context), triggering a softlockup detection code to panic. Binding evtchn:qemu-dm to next online VCPU, will spread hardirq processing evenly across different CPU. Later, irqbalance will try to balance evtchn:qemu-dm, if required. Signed-off-by: Anoob Soman Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross