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2020-10-23xen/events: unmask a fifo event channel only if it was maskedJuergen Gross1-0/+3
Unmasking an event channel with fifo events channels being used can require a hypercall to be made, so try to avoid that by checking whether the event channel was really masked. Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-5-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-23xen/events: only register debug interrupt for 2-level eventsJuergen Gross1-4/+6
xen_debug_interrupt() is specific to 2-level event handling. So don't register it with fifo event handling being active. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-4-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-23xen/events: make struct irq_info private to events_base.cJuergen Gross4-73/+73
The struct irq_info of Xen's event handling is used only for two evtchn_ops functions outside of events_base.c. Those two functions can easily be switched to avoid that usage. This allows to make struct irq_info and its related access functions private to events_base.c. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-3-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-23xen: remove no longer used functionsJuergen Gross1-21/+0
With the switch to the lateeoi model for interdomain event channels some functions are no longer in use. Remove them. Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20201022094907.28560-2-jgross@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2020-10-20xen/events: block rogue events for some timeJuergen Gross2-6/+24
In order to avoid high dom0 load due to rogue guests sending events at high frequency, block those events in case there was no action needed in dom0 to handle the events. This is done by adding a per-event counter, which set to zero in case an EOI without the XEN_EOI_FLAG_SPURIOUS is received from a backend driver, and incremented when this flag has been set. In case the counter is 2 or higher delay the EOI by 1 << (cnt - 2) jiffies, but not more than 1 second. In order not to waste memory shorten the per-event refcnt to two bytes (it should normally never exceed a value of 2). Add an overflow check to evtchn_get() to make sure the 2 bytes really won't overflow. This is part of XSA-332. Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20xen/events: defer eoi in case of excessive number of eventsJuergen Gross4-32/+208
In case rogue guests are sending events at high frequency it might happen that xen_evtchn_do_upcall() won't stop processing events in dom0. As this is done in irq handling a crash might be the result. In order to avoid that, delay further inter-domain events after some time in xen_evtchn_do_upcall() by forcing eoi processing into a worker on the same cpu, thus inhibiting new events coming in. The time after which eoi processing is to be delayed is configurable via a new module parameter "event_loop_timeout" which specifies the maximum event loop time in jiffies (default: 2, the value was chosen after some tests showing that a value of 2 was the lowest with an only slight drop of dom0 network throughput while multiple guests performed an event storm). How long eoi processing will be delayed can be specified via another parameter "event_eoi_delay" (again in jiffies, default 10, again the value was chosen after testing with different delay values). This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20xen/events: use a common cpu hotplug hook for event channelsJuergen Gross3-21/+47
Today only fifo event channels have a cpu hotplug callback. In order to prepare for more percpu (de)init work move that callback into events_base.c and add percpu_init() and percpu_deinit() hooks to struct evtchn_ops. This is part of XSA-332. Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20xen/events: add a new "late EOI" evtchn frameworkJuergen Gross1-17/+134
In order to avoid tight event channel related IRQ loops add a new framework of "late EOI" handling: the IRQ the event channel is bound to will be masked until the event has been handled and the related driver is capable to handle another event. The driver is responsible for unmasking the event channel via the new function xen_irq_lateeoi(). This is similar to binding an event channel to a threaded IRQ, but without having to structure the driver accordingly. In order to support a future special handling in case a rogue guest is sending lots of unsolicited events, add a flag to xen_irq_lateeoi() which can be set by the caller to indicate the event was a spurious one. This is part of XSA-332. Cc: stable@vger.kernel.org Reported-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20xen/events: fix race in evtchn_fifo_unmask()Juergen Gross1-4/+9
Unmasking a fifo event channel can result in unmasking it twice, once directly in the kernel and once via a hypercall in case the event was pending. Fix that by doing the local unmask only if the event is not pending. This is part of XSA-332. Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>
2020-10-20xen/events: add a proper barrier to 2-level uevent unmaskingJuergen Gross1-0/+2
A follow-up patch will require certain write to happen before an event channel is unmasked. While the memory barrier is not strictly necessary for all the callers, the main one will need it. In order to avoid an extra memory barrier when using fifo event channels, mandate evtchn_unmask() to provide write ordering. The 2-level event handling unmask operation is missing an appropriate barrier, so add it. Fifo event channels are fine in this regard due to using sync_cmpxchg(). This is part of XSA-332. Cc: stable@vger.kernel.org Suggested-by: Julien Grall <julien@xen.org> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Julien Grall <jgrall@amazon.com> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-20xen/events: avoid removing an event channel while handling itJuergen Gross1-5/+36
Today it can happen that an event channel is being removed from the system while the event handling loop is active. This can lead to a race resulting in crashes or WARN() splats when trying to access the irq_info structure related to the event channel. Fix this problem by using a rwlock taken as reader in the event handling loop and as writer when deallocating the irq_info structure. As the observed problem was a NULL dereference in evtchn_from_irq() make this function more robust against races by testing the irq_info pointer to be not NULL before dereferencing it. And finally make all accesses to evtchn_to_irq[row][col] atomic ones in order to avoid seeing partial updates of an array element in irq handling. Note that irq handling can be entered only for event channels which have been valid before, so any not populated row isn't a problem in this regard, as rows are only ever added and never removed. This is XSA-331. Cc: stable@vger.kernel.org Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Reported-by: Jinoh Kang <luke1337@theori.io> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Wei Liu <wl@xen.org>
2020-10-01xen/events: don't use chip_data for legacy IRQsJuergen Gross1-8/+21
Since commit c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.") Xen is using the chip_data pointer for storing IRQ specific data. When running as a HVM domain this can result in problems for legacy IRQs, as those might use chip_data for their own purposes. Use a local array for this purpose in case of legacy IRQs, avoiding the double use. Cc: stable@vger.kernel.org Fixes: c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.") Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Stefan Bader <stefan.bader@canonical.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20200930091614.13660-1-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2020-08-27XEN uses irqdesc::irq_data_common::handler_data to store a per interruptThomas Gleixner1-8/+8
XEN data pointer which contains XEN specific information. handler data is meant for interrupt handlers and not for storing irq chip specific information as some devices require handler data to store internal per interrupt information, e.g. pinctrl/GPIO chained interrupt handlers. This obviously creates a conflict of interests and crashes the machine because the XEN pointer is overwritten by the driver pointer. As the XEN data is not handler specific it should be stored in irqdesc::irq_data::chip_data instead. A simple sed s/irq_[sg]et_handler_data/irq_[sg]et_chip_data/ cures that. Cc: stable@vger.kernel.org Reported-by: Roman Shaposhnik <roman@zededa.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Roman Shaposhnik <roman@zededa.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/87lfi2yckt.fsf@nanos.tec.linutronix.de Signed-off-by: Juergen Gross <jgross@suse.com>
2020-06-11x86/entry: Convert XEN hypercall vector to IDTENTRY_SYSVECThomas Gleixner1-4/+2
Convert the last oldstyle defined vector to IDTENTRY_SYSVEC: - Implement the C entry point with DEFINE_IDTENTRY_SYSVEC - Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC - Remove the ASM idtentries in 64-bit - Remove the BUILD_INTERRUPT entries in 32-bit - Remove the old prototypes Fixup the related XEN code by providing the primary C entry point in x86 to avoid cluttering the generic code with X86'isms. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202119.741950104@linutronix.de
2020-06-11x86/xen: Split HVM vector callback setup and interrupt gate allocationVitaly Kuznetsov1-11/+17
As a preparatory change for making alloc_intr_gate() __init split xen_callback_vector() into callback vector setup via hypercall (xen_setup_callback_vector()) and interrupt gate allocation (xen_alloc_callback_vector()). xen_setup_callback_vector() is being called twice: on init and upon system resume from xen_hvm_post_suspend(). alloc_intr_gate() only needs to be called once. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200428093824.1451532-2-vkuznets@redhat.com
2020-04-07xen: Use evtchn_type_t as a type for event channelsYan Yankovskyi4-79/+82
Make event channel functions pass event channel port using evtchn_port_t type. It eliminates signed <-> unsigned conversion. Signed-off-by: Yan Yankovskyi <yyankovskyi@gmail.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20200323152343.GA28422@kbp1-lhp-F74019 Signed-off-by: Juergen Gross <jgross@suse.com>
2019-12-02xen/events: remove event handling recursion detectionJuergen Gross1-13/+3
__xen_evtchn_do_upcall() contains guards against being called recursively. This mechanism was introduced in the early pvops times (kernel 2.6.26) when there were all the Xen backend drivers missing from the upstream kernel, and some of those out-of-tree drivers were enabling interrupts in their event handlers (which was explicitly allowed in the initial XenoLinux). Nowadays we don't need to support those old drivers any more and the capability to allow recursive calls of __xen_evtchn_do_upcall() can be removed. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-09-26xen/events: remove unlikely() from WARN() conditionDenis Efremov1-1/+1
"unlikely(WARN(x))" is excessive. WARN() already uses unlikely() internally. Link: http://lkml.kernel.org/r/20190829165025.15750-4-efremov@linux.com Signed-off-by: Denis Efremov <efremov@linux.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Joe Perches <joe@perches.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-17xen/events: fix binding user event channels to cpusJuergen Gross1-2/+10
When binding an interdomain event channel to a vcpu via IOCTL_EVTCHN_BIND_INTERDOMAIN not only the event channel needs to be bound, but the affinity of the associated IRQi must be changed, too. Otherwise the IRQ and the event channel won't be moved to another vcpu in case the original vcpu they were bound to is going offline. Cc: <stable@vger.kernel.org> # 4.13 Fixes: c48f64ab472389df ("xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPU") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 81Thomas Gleixner1-3/+1
Based on 1 normalized pattern(s): this source code is licensed under the gnu general public license version 2 or later see the file copying for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520075211.129205147@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier for missed filesThomas Gleixner1-0/+1
Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-17x86/irq/32: Invoke irq_ctx_init() from init_IRQ()Thomas Gleixner1-1/+0
irq_ctx_init() is invoked from native_init_IRQ() or from xen_init_IRQ() code. There is no reason to have this split. The interrupt stacks must be allocated no matter what. Invoke it from init_IRQ() before invoking the native or XEN init implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Josh Abraham <j.abraham1776@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20190414160146.001162606@linutronix.de
2019-01-16xen: Fix x86 sched_clock() interface for xenJuergen Gross1-1/+1
Commit f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface") broke Xen guest time handling across migration: [ 187.249951] Freezing user space processes ... (elapsed 0.001 seconds) done. [ 187.251137] OOM killer disabled. [ 187.251137] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. [ 187.252299] suspending xenstore... [ 187.266987] xen:grant_table: Grant tables using version 1 layout [18446743811.706476] OOM killer enabled. [18446743811.706478] Restarting tasks ... done. [18446743811.720505] Setting capacity to 16777216 Fix that by setting xen_sched_clock_offset at resume time to ensure a monotonic clock value. [boris: replaced pr_info() with pr_info_once() in xen_callback_vector() to avoid printing with incorrect timestamp during resume (as we haven't re-adjusted the clock yet)] Fixes: f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' sched_clock() interface") Cc: <stable@vger.kernel.org> # 4.11 Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-10-31mm: remove include/linux/bootmem.hMike Rapoport1-1/+1
Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-09-14xen: fix GCC warning and remove duplicate EVTCHN_ROW/EVTCHN_COL usageJosh Abraham1-1/+1
This patch removes duplicate macro useage in events_base.c. It also fixes gcc warning: variable ‘col’ set but not used [-Wunused-but-set-variable] Signed-off-by: Joshua Abraham <j.abraham1776@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2018-06-22xen: Remove unnecessary BUG_ON from __unbind_from_irq()Boris Ostrovsky1-2/+0
Commit 910f8befdf5b ("xen/pirq: fix error path cleanup when binding MSIs") fixed a couple of errors in error cleanup path of xen_bind_pirq_msi_to_irq(). This cleanup allowed a call to __unbind_from_irq() with an unbound irq, which would result in triggering the BUG_ON there. Since there is really no reason for the BUG_ON (xen_free_irq() can operate on unbound irqs) we can remove it. Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: stable@vger.kernel.org Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2018-02-28xen/pirq: fix error path cleanup when binding MSIsRoger Pau Monne1-2/+2
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 <mirhadih@amazon.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Amit Shah <aams@amazon.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-07Merge tag 'for-linus-4.14b-rc1-tag' of ↵Linus Torvalds1-4/+3
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip 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 ...
2017-08-31xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init()Julien Grall1-4/+3
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] [<ffff00000808a5c0>] dump_backtrace+0x0/0x270 [ 0.020222] [<ffff00000808a95c>] show_stack+0x24/0x30 [ 0.020244] [<ffff000008c1ef20>] dump_stack+0xb8/0xf0 [ 0.020267] [<ffff0000081128c0>] ___might_sleep+0x1c8/0x1f8 [ 0.020291] [<ffff000008112948>] __might_sleep+0x58/0x90 [ 0.020313] [<ffff0000082171b8>] __alloc_pages_nodemask+0x1c0/0x12e8 [ 0.020338] [<ffff00000827a110>] alloc_page_interleave+0x38/0x88 [ 0.020363] [<ffff00000827a904>] alloc_pages_current+0xdc/0xf0 [ 0.020387] [<ffff000008211f38>] __get_free_pages+0x28/0x50 [ 0.020411] [<ffff0000086566a4>] evtchn_fifo_alloc_control_block+0x2c/0xa0 [ 0.020437] [<ffff0000091747b0>] xen_evtchn_fifo_init+0x38/0xb4 [ 0.020461] [<ffff0000091746c0>] xen_init_IRQ+0x44/0xc8 [ 0.020484] [<ffff000009128adc>] xen_guest_init+0x250/0x300 [ 0.020507] [<ffff000008083974>] do_one_initcall+0x44/0x130 [ 0.020531] [<ffff000009120df8>] kernel_init_freeable+0x120/0x288 [ 0.020556] [<ffff000008c31ca8>] kernel_init+0x18/0x110 [ 0.020578] [<ffff000008083710>] 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 <julien.grall@arm.com> Reported-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Fixes: 1fe565517b57 ("xen/events: use the FIFO-based ABI if available") Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-08-29x86/idt: Simplify alloc_intr_gate()Thomas Gleixner1-4/+2
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 <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170828064959.580830286@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-11xen/events: Fix interrupt lost during irq_disable and irq_enableLiu Shuo1-1/+1
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 <shuo.a.liu@intel.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-07-27xen: dont fiddle with event channel masking in suspend/resumeJuergen Gross1-10/+3
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 <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-07-06Merge tag 'for-linus-4.13-rc1-tag' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip 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()
2017-06-22xen/events: Add support for effective affinity maskThomas Gleixner1-1/+5
Update the effective affinity mask when an interrupt was successfully targeted to a CPU. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Keith Busch <keith.busch@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170619235446.799944725@linutronix.de
2017-06-13xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPUAnoob Soman1-3/+3
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 <anoob.soman@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-05-02xen: Revert commits da72ff5bfcb0 and 72a9b186292dBoris Ostrovsky1-8/+17
Recent discussion (http://marc.info/?l=xen-devel&m=149192184523741) established that commit 72a9b186292d ("xen: Remove event channel notification through Xen PCI platform device") (and thus commit da72ff5bfcb0 ("partially revert "xen: Remove event channel notification through Xen PCI platform device"")) are unnecessary and, in fact, prevent HVM guests from booting on Xen releases prior to 4.0 Therefore we revert both of those commits. The summary of that discussion is below: Here is the brief summary of the current situation: Before the offending commit (72a9b186292): 1) INTx does not work because of the reset_watches path. 2) The reset_watches path is only taken if you have Xen > 4.0 3) The Linux Kernel by default will use vector inject if the hypervisor support. So even INTx does not work no body running the kernel with Xen > 4.0 would notice. Unless he explicitly disabled this feature either in the kernel or in Xen (and this can only be disabled by modifying the code, not user-supported way to do it). After the offending commit (+ partial revert): 1) INTx is no longer support for HVM (only for PV guests). 2) Any HVM guest The kernel will not boot on Xen < 4.0 which does not have vector injection support. Since the only other mode supported is INTx which. So based on this summary, I think before commit (72a9b186292) we were in much better position from a user point of view. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-02-07xen/x86: Remove PVH supportBoris Ostrovsky1-1/+0
We are replacing existing PVH guests with new implementation. We are keeping xen_pvh_domain() macro (for now set to zero) because when we introduce new PVH implementation later in this series we will reuse current PVH-specific code (xen_pvh_gnttab_setup()), and that code is conditioned by 'if (xen_pvh_domain())'. (We will also need a noop xen_pvh_domain() for !CONFIG_XEN_PVH). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2017-01-05Merge tag 'for-linus-4.10-rc2-tag' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes and cleanups from Juergen Gross: - small fixes for xenbus driver - one fix for xen dom0 boot on huge system - small cleanups * tag 'for-linus-4.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: Xen: ARM: Zero reserved fields of xatp before making hypervisor call xen: events: Replace BUG() with BUG_ON() xen: remove stale xs_input_avail() from header xen: return xenstore command failures via response instead of rc xen: xenbus driver must not accept invalid transaction ids xen/evtchn: use rb_entry() xen/setup: Don't relocate p2m over existing one
2017-01-03xen: events: Replace BUG() with BUG_ON()Shyam Saini1-2/+1
Replace BUG() with BUG_ON() using coccinelle Signed-off-by: Shyam Saini <mayhs11saini@gmail.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-12-25cpu/hotplug: Cleanup state namesThomas Gleixner1-1/+1
When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-13Merge tag 'for-linus-4.10-rc0-tag' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: "Xen features and fixes for 4.10 These are some fixes, a move of some arm related headers to share them between arm and arm64 and a series introducing a helper to make code more readable. The most notable change is David stepping down as maintainer of the Xen hypervisor interface. This results in me sending you the pull requests for Xen related code from now on" * tag 'for-linus-4.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits) xen/balloon: Only mark a page as managed when it is released xenbus: fix deadlock on writes to /proc/xen/xenbus xen/scsifront: don't request a slot on the ring until request is ready xen/x86: Increase xen_e820_map to E820_X_MAX possible entries x86: Make E820_X_MAX unconditionally larger than E820MAX xen/pci: Bubble up error and fix description. xen: xenbus: set error code on failure xen: set error code on failures arm/xen: Use alloc_percpu rather than __alloc_percpu arm/arm64: xen: Move shared architecture headers to include/xen/arm xen/events: use xen_vcpu_id mapping for EVTCHNOP_status xen/gntdev: Use VM_MIXEDMAP instead of VM_IO to avoid NUMA balancing xen-scsifront: Add a missing call to kfree MAINTAINERS: update XEN HYPERVISOR INTERFACE xenfs: Use proc_create_mount_point() to create /proc/xen xen-platform: use builtin_pci_driver xen-netback: fix error handling output xen: make use of xenbus_read_unsigned() in xenbus xen: make use of xenbus_read_unsigned() in xen-pciback xen: make use of xenbus_read_unsigned() in xen-fbfront ...
2016-12-09x86: Remove empty idle.h headerThomas Gleixner1-1/+0
One include less is always a good thing(tm). Good riddance. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/20161209182912.2726-6-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-30xen/events: use xen_vcpu_id mapping for EVTCHNOP_statusVitaly Kuznetsov1-1/+1
EVTCHNOP_status hypercall returns Xen's idea of vcpu id so we need to compare it against xen_vcpu_id mapping, not the Linux cpu id. Suggested-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-18x86/idle: Remove enter_idle(), exit_idle()Len Brown1-1/+0
Upon removal of the is_idle flag, these routines became NOPs. Signed-off-by: Len Brown <len.brown@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/822f2c22cc5890f7b8ea0eeec60277eb44505b4e.1479449716.git.len.brown@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-30xen: Remove event channel notification through Xen PCI platform deviceKarimAllah Ahmed1-17/+9
Ever since commit 254d1a3f02eb ("xen/pv-on-hvm kexec: shutdown watches from old kernel") using the INTx interrupt from Xen PCI platform device for event channel notification would just lockup the guest during bootup. postcore_initcall now calls xs_reset_watches which will eventually try to read a value from XenStore and will get stuck on read_reply at XenBus forever since the platform driver is not probed yet and its INTx interrupt handler is not registered yet. That means that the guest can not be notified at this moment of any pending event channels and none of the per-event handlers will ever be invoked (including the XenStore one) and the reply will never be picked up by the kernel. The exact stack where things get stuck during xenbus_init: -xenbus_init -xs_init -xs_reset_watches -xenbus_scanf -xenbus_read -xs_single -xs_single -xs_talkv Vector callbacks have always been the favourite event notification mechanism since their introduction in commit 38e20b07efd5 ("x86/xen: event channels delivery on HVM.") and the vector callback feature has always been advertised for quite some time by Xen that's why INTx was broken for several years now without impacting anyone. Luckily this also means that event channel notification through INTx is basically dead-code which can be safely removed without impacting anybody since it has been effectively disabled for more than 4 years with nobody complaining about it (at least as far as I'm aware of). This commit removes event channel notification through Xen PCI platform device. Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Juergen Gross <jgross@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Julien Grall <julien.grall@citrix.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Ross Lagerwall <ross.lagerwall@citrix.com> Cc: xen-devel@lists.xenproject.org Cc: linux-kernel@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: Anthony Liguori <aliguori@amazon.com> Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30xen/events: Convert to hotplug state machineSebastian Andrzej Siewior1-22/+12
Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25xen/events: fifo: use xen_vcpu_id mappingVitaly Kuznetsov1-1/+1
EVTCHNOP_init_control has vCPU id as a parameter and Xen's idea of vCPU id should be used. Use the newly introduced xen_vcpu_id mapping to convert it from Linux's id. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25xen/events: use xen_vcpu_id mapping in events_baseVitaly Kuznetsov1-5/+5
EVTCHNOP_bind_ipi and EVTCHNOP_bind_virq pass vCPU id as a parameter and Xen's idea of vCPU id should be used. Use the newly introduced xen_vcpu_id mapping to convert it from Linux's id. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>