22 May, 2020
1 commit
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Commit a926f81d2f6c ("xen/cpuhotplug: Replace cpu_up/down() with
device_online/offline()") replaced cpu_down() with device_offline()
call which requires that the CPU has been registered before. This
registration, however, happens later from topology_init() which
is called as subsys_initcall(). setup_vcpu_hotplug_event(), on the
other hand, is invoked earlier, during arch_initcall().As result, booting a PV(H) guest with vcpus < maxvcpus causes a crash.
Move setup_vcpu_hotplug_event() (and therefore setup_cpu_watcher()) to
late_initcall(). In addition, instead of performing all offlining steps
in setup_cpu_watcher() simply call disable_hotplug_cpu().Fixes: a926f81d2f6c (xen/cpuhotplug: Replace cpu_up/down() with device_online/offline()"
Signed-off-by: Boris Ostrovsky
Link: https://lore.kernel.org/r/1588976923-3667-1-git-send-email-boris.ostrovsky@oracle.com
Reviewed-by: Juergen Gross
Signed-off-by: Boris Ostrovsky
25 Mar, 2020
1 commit
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The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().See commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.This also prepares to make cpu_up/down() a private interface of the cpu
subsystem.Signed-off-by: Qais Yousef
Signed-off-by: Thomas Gleixner
Reviewed-by: Juergen Gross
Link: https://lkml.kernel.org/r/20200323135110.30522-14-qais.yousef@arm.com
09 Mar, 2019
1 commit
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The "cpu" variable comes from the sscanf() so Smatch marks it as
untrusted data. We can't pass a higher value than "nr_cpu_ids" to
cpu_possible() or it results in an out of bounds access.Fixes: d68d82afd4c8 ("xen: implement CPU hotplugging")
Signed-off-by: Dan Carpenter
Reviewed-by: Juergen Gross
Signed-off-by: Juergen Gross
14 Sep, 2018
1 commit
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The command 'xl vcpu-set 0 0', issued in dom0, will crash dom0:
BUG: unable to handle kernel NULL pointer dereference at 00000000000002d8
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 7 PID: 65 Comm: xenwatch Not tainted 4.19.0-rc2-1.ga9462db-default #1 openSUSE Tumbleweed (unreleased)
Hardware name: Intel Corporation S5520UR/S5520UR, BIOS S5500.86B.01.00.0050.050620101605 05/06/2010
RIP: e030:device_offline+0x9/0xb0
Code: 77 24 00 e9 ce fe ff ff 48 8b 13 e9 68 ff ff ff 48 8b 13 e9 29 ff ff ff 48 8b 13 e9 ea fe ff ff 90 66 66 66 66 90 41 54 55 53 87 d8 02 00 00 01 0f 85 88 00 00 00 48 c7 c2 20 09 60 81 31 f6
RSP: e02b:ffffc90040f27e80 EFLAGS: 00010203
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff8801f3800000 RSI: ffffc90040f27e70 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff820e47b3 R09: 0000000000000000
R10: 0000000000007ff0 R11: 0000000000000000 R12: ffffffff822e6d30
R13: dead000000000200 R14: dead000000000100 R15: ffffffff8158b4e0
FS: 00007ffa595158c0(0000) GS:ffff8801f39c0000(0000) knlGS:0000000000000000
CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000002d8 CR3: 00000001d9602000 CR4: 0000000000002660
Call Trace:
handle_vcpu_hotplug_event+0xb5/0xc0
xenwatch_thread+0x80/0x140
? wait_woken+0x80/0x80
kthread+0x112/0x130
? kthread_create_worker_on_cpu+0x40/0x40
ret_from_fork+0x3a/0x50This happens because handle_vcpu_hotplug_event is called twice. In the
first iteration cpu_present is still true, in the second iteration
cpu_present is false which causes get_cpu_device to return NULL.
In case of cpu#0, cpu_online is apparently always true.Fix this crash by checking if the cpu can be hotplugged, which is false
for a cpu that was just removed.Also check if the cpu was actually offlined by device_remove, otherwise
leave the cpu_present state as it is.Rearrange to code to do all work with device_hotplug_lock held.
Signed-off-by: Olaf Hering
Reviewed-by: Juergen Gross
Signed-off-by: Boris Ostrovsky
02 Nov, 2017
1 commit
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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
Reviewed-by: Philippe Ombredanne
Reviewed-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
10 Feb, 2017
1 commit
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Today a Xenstore watch event is delivered via a callback function
declared as:void (*callback)(struct xenbus_watch *,
const char **vec, unsigned int len);As all watch events only ever come with two parameters (path and token)
changing the prototype to:void (*callback)(struct xenbus_watch *,
const char *path, const char *token);is the natural thing to do.
Apply this change and adapt all users.
Cc: konrad.wilk@oracle.com
Cc: roger.pau@citrix.com
Cc: wei.liu2@citrix.com
Cc: paul.durrant@citrix.com
Cc: netdev@vger.kernel.orgSigned-off-by: Juergen Gross
Reviewed-by: Paul Durrant
Reviewed-by: Wei Liu
Reviewed-by: Roger Pau Monné
Reviewed-by: Boris Ostrovsky
Signed-off-by: Boris Ostrovsky
07 Feb, 2017
1 commit
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PVH guests don't (yet) receive ACPI hotplug interrupts and therefore
need to monitor xenstore for CPU hotplug event.Signed-off-by: Boris Ostrovsky
Reviewed-by: Juergen Gross
23 Oct, 2015
2 commits
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When offlining a cpu, instead of cpu_down, call device_offline, which
also takes care of updating the cpu.dev.offline field. This keeps the
sysfs file /sys/devices/system/cpu/cpuN/online, up to date. Also move
the call to disable_hotplug_cpu, because it makes more sense to have it
there.We don't call device_online at cpu-hotplug time, because that would
immediately take the cpu online, while we want to retain the current
behaviour: the user needs to explicitly enable the cpu after it has
been hotplugged.Signed-off-by: Stefano Stabellini
Reviewed-by: Boris Ostrovsky
CC: konrad.wilk@oracle.com
CC: boris.ostrovsky@oracle.com
CC: david.vrabel@citrix.com -
Build cpu_hotplug for ARM and ARM64 guests.
Rename arch_(un)register_cpu to xen_(un)register_cpu and provide an
empty implementation on ARM and ARM64. On x86 just call
arch_(un)register_cpu as we are already doing.Initialize cpu_hotplug on ARM.
Signed-off-by: Stefano Stabellini
Reviewed-by: Julien Grall
Reviewed-by: Boris Ostrovsky
28 Jun, 2013
1 commit
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Convert printks to pr_ (excludes printk(KERN_DEBUG...)
to be more consistent throughout the xen subsystem.Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME
Coalesce formats and add missing word spaces
Add missing newlines
Align arguments and reflow to 80 columns
Remove DRV_NAME from formats as pr_fmt adds the same contentThis does change some of the prefixes of these messages
but it also does make them more consistent.Signed-off-by: Joe Perches
Signed-off-by: Konrad Rzeszutek Wilk
16 Jan, 2013
1 commit
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At the same time reduce the local buffers to 16 bytes each.
Signed-off-by: Jan Beulich
Signed-off-by: Konrad Rzeszutek Wilk
04 Feb, 2012
1 commit
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When the initial domain starts, it prints (depending on the
amount of CPUs) a slew of
XENBUS: Unable to read cpu state
XENBUS: Unable to read cpu state
XENBUS: Unable to read cpu state
XENBUS: Unable to read cpu statewhich provide no useful information - as the error is a valid
issue - but not on the initial domain. The reason is that the
XenStore is not accessible at that time (it is after all the
first guest) so the CPU hotplug watch cannot parse "availability/cpu"
attribute.Signed-off-by: Konrad Rzeszutek Wilk
12 Dec, 2009
1 commit
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* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (109 commits)
PCI: fix coding style issue in pci_save_state()
PCI: add pci_request_acs
PCI: fix BUG_ON triggered by logical PCIe root port removal
PCI: remove ifdefed pci_cleanup_aer_correct_error_status
PCI: unconditionally clear AER uncorr status register during cleanup
x86/PCI: claim SR-IOV BARs in pcibios_allocate_resource
PCI: portdrv: remove redundant definitions
PCI: portdrv: remove unnecessary struct pcie_port_data
PCI: portdrv: minor cleanup for pcie_port_device_register
PCI: portdrv: add missing irq cleanup
PCI: portdrv: enable device before irq initialization
PCI: portdrv: cleanup service irqs initialization
PCI: portdrv: check capabilities first
PCI: portdrv: move PME capability check
PCI: portdrv: remove redundant pcie type calculation
PCI: portdrv: cleanup pcie_device registration
PCI: portdrv: remove redundant pcie_port_device_probe
PCI: Always set prefetchable base/limit upper32 registers
PCI: read-modify-write the pcie device control register when initiating pcie flr
PCI: show dma_mask bits in /sys
...Fixed up conflicts in:
arch/x86/kernel/amd_iommu_init.c
drivers/pci/dmar.c
drivers/pci/hotplug/acpiphp_glue.c
05 Nov, 2009
1 commit
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Move xen_domain and related tests out of asm-x86 to xen/xen.h so they
can be included whenever they are necessary.Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Jesse Barnes
04 Nov, 2009
1 commit
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Signed-off-by: Rusty Russell
Cc: Jeremy Fitzhardinge
LKML-Reference:
Signed-off-by: Ingo Molnar
09 Apr, 2009
1 commit
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If a VM is booted with offline VCPUs then unplug them during boot. Determining
the availability of a VCPU requires access to XenStore which is not available
at the point smp_prepare_cpus() is called, therefore we bring up all VCPUS
initially and unplug the offline ones as soon as XenStore becomes available.Signed-off-by: Ian Campbell
13 Mar, 2009
1 commit
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Impact: cleanup
In particular, *map are deprecated, and you have to use the accessors
as *mask are const.Signed-off-by: Rusty Russell
To: Jeremy Fitzhardinge
23 Oct, 2008
1 commit
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Signed-off-by: Al Viro
Signed-off-by: H. Peter Anvin
05 Sep, 2008
1 commit
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Signed-off-by: Alex Nixon
Signed-off-by: Ingo Molnar
25 Aug, 2008
1 commit
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Note the changes from 2.6.18-xen CPU hotplugging:
A vcpu_down request from the remote admin via Xenbus both hotunplugs the
CPU, and disables it by removing it from the cpu_present map, and removing
its entry in /sys.A vcpu_up request from the remote admin only re-enables the CPU, and does
not immediately bring the CPU up. A udev event is emitted, which can be
caught by the user if he wishes to automatically re-up CPUs when available,
or implement a more complex policy.Signed-off-by: Alex Nixon
Acked-by: Jeremy Fitzhardinge
Signed-off-by: Ingo Molnar